The Late Cretaceous and Tertiary Rocks of New Zealand.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 60, 1930, Page 271

The Late Cretaceous and Tertiary Rocks of New Zealand. By J. Henderson. [Presidential address to Geological Section, Fourth Science Congress of New Zealand Institute, read January 25th, 1929; received by Editor, 13th April, 1929; issued separately, 15th August, 1929.] Contents. Introduction. Western and Central Nelson. Criteria of Correlation. Marlborough and North Canterbury. Taranaki and South-west Auckland. South Canterbury and East Otago. North Auckland. Southland and West Otago. East Cape—Hawke Bay District. Otago Central. Hawke Bay—Palliser Bay District. Conclusion. Tertiary Igneous Rocks of the North Island. List of Literature. Introduction. All New Zealand geologists have noted the great difference in the degree of consolidation and amount of deformation of the rocks of Tertiary and late Cretaceous age as compared with those of the more ancient terrains on which they rest. Some of the early observers supposed that the strongly folded rocks of the middle Mesozoic belonged to a great anticlinorium of which the present axial chain of New Zealand is the eastern half that still remains undenuded; along its base and on the eroded and submerged flanks, sediments of late Cretaceous and Tertiary age accumulated. Hutton, who gave its final form to this explanation of the essential unity of the late Cretaceous and Tertiary sequence, also insisted that several unconformities occurred, including one between the Cretaceous and Tertiary. Hector, on the other hand, contended that the Cretaceous and Tertiary were completely accordant, though he admitted erosion intervals during the Tertiary. Marshall goes still further and denies that any important stratigraphic break occurs in the succession from the late Cretaceous to the Pliocene. McKay showed that the ideas of the tectonics of New Zealand held by Hochstetter, Haast, and Hutton were incorrect, and most geologists now accept some development of McKay's views on the structure of New Zealand and some modification of Hutton's on the stratigraphy. Thomson has proposed several stage names which have been generally accepted, and, in order to emphasize the close relation of the late Cretaceous and Tertiary beds, suggested that all should be included in the “Notocene,” a term which, though convenient, has unfortunate implications. Though New Zealand is a small country and the strata here to be discussed were laid down between two major diastrophic movements there is, nevertheless, great divergence of opinion concerning the correlation of the beds outcropping in different areas. In part this is due to the conditions of deposition of the strata themselves and in part to the separation of areas occupied by them, a separation

largely brought about by the last great orogenic revolution and the erosion that followed. The development of McKay's explanation of the structure of New Zealand has removed one of the chief causes that led Hutton and other early geologists astray when they were considering the relations of the late Cretaceous and Tertiary beds both to the older folded rocks and to each other. Cotton and others, following McKay, have pointed out how vast had been the erosion of the older rocks before the younger were deposited, and Marshall has shown what a source of confusion the extensive overlap following the slow submergence of the peneplaned surface has proved. To the writer the conditions existing at the time of deposition of the strata do not seem to have been adequately considered. It is usual to assume that greensands and limestones are deposits characteristically formed in relatively deep water; but in so many places in New Zealand are greensands found as basal beds that where encountered other evidence of shallow water and of an erosion interval large or small is to be expected. In many parts basal limestones occur, and in some localities these contain pebbles of the underlying rocks and also limestone, probably intraformational. In the Te Kuiti district thick Tertiary limestone, in many places of high grade, is separated from the Mesozoics over many square miles, only by thin layers of shale, sandstone, or conglomerate. Vaughan* T. Wayland Vaughan, “Oceanography in its Relations to other Earth Sciences.” Jour. Wash. Acad. Sc., vol. 14, p. 328 (1924). emphasizes “the fact “that limestone of a high degree of purity, that is from 95 to over “99 per cent. CaCO3, is usually either a very shallow water or only “a moderately deep-water deposit. The purest limestone is a very “shallow water deposit. It is time that the erroneous statements in “text-books that pure limestones are deep-water deposits should be “erased. Whether a shoal-water deposit is pure limestone or not is “determined not by depth of water but by outwash from the land. “Where there is no outwash of siliceous, aluminous, and ferruginous “material, beach deposits may contain more than 95 per cent. of “CaCO3, and the shallow water Key West and Bahamian oolites are “over 99 per cent. CaCO3. None of the deep-sea deposits nearly “approach these deposits in purity.” Even the Amuri limestone, the greater part of which consists of exceedingly fine-grained calcareous mud, may well be a shoal-water deposit similar to the shallow-water calcareous muds of the Key region of Florida,† Ibid, pp. 315–27. the Bahamas,‡ R. M. Field, “The Great Bahama Bank. Studies in Marine Carbonate Sediments,” Amer. Jour. Sc., vol. 16, pp. 239–46 (1928). and other parts of the tropics and sub-tropics. In New Zealand the other marine sediments of Tertiary and late Cretaceous age are chiefly calcareous sandstones, argillaceous sandstones, and mudstones, in many places interbedded. Conglomerates, quartz grits, and carbonaceous shales also occur. All these deposits, if not characteristic of shallow water, are at least known to be laid down in it at times. Again, at many points the mudstones are interbedded with conglomerates and at others the limestones are current-bedded. The whole succession is thought to have been laid down in the shallow, or at most moderately deep, water of an epicontinental shelf.

Criteria OF Correlation. The most satisfactory method of correlating is by actually tracing a geological formation from one area to another, and this can be done more or less effectively in each of the several regions in which the younger rocks of New Zealand occur. The lithological peculiarities of any member of a series and the peculiarities of the succession of the several members have wider application. This method of correlation, which is now being developed in great elaboration in Great Britain and is being used by the staff of the Taranki Oilfields, has some obvious limitations. Palaeontological comparisons provide evidence for correlations over still wider areas, but in this method the effects of differences in climate and station and of the conditions of preservation of the remains require most careful consideration. So little is known of the climates of the past and of the effects of climate on many marine organisms that climatic history as yet provides but a precarious basis for comparison. Physiographic history is used in correlating land surfaces and in the special case of base-levelling, particularly where complemented by transgressive deposits on a base-level, provides criteria of the highest value. It must be pointed out, however, that different parts of the same unconformity may be considerably different in age. All the above methods of correlation have their use, and if one can be made to reinforce and supplement another the likelihood of the correlation increases. The shorter the distance separating the rocks compared the better, for all distant correlations involve some measure of inexactness. As Chamberlin* T. C. Chamberlin. “Diastrophism as the Ultimate Basis of Correlation,” Jour. Geol., vol. 17, pp. 685–93 (1909). cogently argues, earth-movements are the ultimate bases of all geological correlations. It may be granted that before and after each great orogenic movement local adjustments occur in the crust that have perhaps no counterpart in neighbouring areas, but that such local adjustments could long continue independently is most unlikely. Thomson (5) has sought to show that New Zealand, during the relatively stable period the deposits of which are here discussed, consisted of a number of areas or “provinces” that had different dynamic histories. He based this hypothesis on rather slender evidence which seems to be capable of other interpretation, and his conclusions are not generally accepted. In the table on p. 285, New Zealand is divided into a number of areas. This subdivision, though in part based on geological considerations, is chiefly geographical and for convenience of description. It will be noted that the Ngaparan and Waiarekan stages are omitted. In the typical locality for the Ngaparan (Oamaru) no marine fossils occur in the Ngapara beds, which cannot therefore be directly correlated with marine beds of the same age that probably occur elsewhere in New Zealand. The Bortonian has been separated from the Waiarekan, since Thomson proposed that stage, and the fauna of the remaining higher part of Waiareka beds in the Oamaru district does not differ essentially from that of the overlying Ototara beds with which the Waiareka beds are here tentatively merged.

Taranaki And South-West Auckland. Perhaps the most complete succession of upper and middle Tertiary strata to be found in New Zealand is that of the area extending north from Wanganui through Taranaki to Te Kuiti. A large part of this area has been geologically examined in detail, the structure is relatively simple, and there is not the slightest doubt of the order of succession of the beds. Fossils, especially in the upper part of the sequence, occur at many horizons, and the type localities for the stages of the Pliocene and upper Miocene are in this region. Since the strata have a general dip toward the south, older beds are successively exposed from south to north. The following sets are recognised: Castlecliff, Nukumaru, Waitotara, Urenui, Tongaporutu, Mohakatino, Mokau, Mahoenui, and Te Kuiti. Marshall and Murdoch (11) have demonstrated palaeontologically that at least three stages are represented in the 3450 ft. of strata exposed along the coast between Wanganui and Waipipi beach. Park (29) had already divided these groups, of which his newer and older Pliocene probably roughly correspond respectively to the Castlecliff and Nukumaru beds, and part of his upper Miocene to the Waitotara beds. Park's newer Pliocene, the Castlecliff beds, contains the thick Kai Iwi blue clay which grades upward into clays and sands and downward into thin-bedded clays and sands and fine pumice gravels. A bed of lignite near their base indicates terrestrial conditions. The Nukumaru beds consist of pebbly shell rock, coarse micaceous current-bedded sands, and loose sandy shell beds. They are several hundred feet thick. The Waitotara beds (21, 43, 45) cover most of the south-eastern third of Taranaki. They consist chiefly of sandstones, argillaceous sandstones and mudstones containing thin irregular bands of shell limestone and pebble beds, deposited at times when the water was shallower than usual. At one or more horizons the sandstones are tufaceous and contain numerous broken crystals of feldspar and hornblende. The beds, which have a general but very gentle southward dip have been estimated to be 3,250 ft. thick. At one point they rest disconformably on an eroded surface of the underlying Urenui beds. The Kaawa beds (42) covering a small area south of Port Waikato are referred to this series on palaeontological grounds. The Urenui beds (45) occupy much of the basins of the Urenui and Waitara whence they extend east into the Whangamomona valley. The strata, which laterally vary a good deal, closely resemble those of the Waitotara series and were almost certainly deposited under similar shallow-water conditions. The conglomeratic and shelly beds are perhaps thicker, more extensive, and more numerous. In places they contain rolled concretions. The tufaceous andesitic material occurs at many horizons. Near the coast the beds are over 2000 ft. thick, but near Whangamomona are less than 1000 ft. This may be due to erosion before the deposition of the Waitotara beds or to overlap eastward on the pre-Urenuian land. At one point the Urenui beds rest with small angular unconformity on the underlying Tongaporutu beds. In several other localities shelly and pebbly conglomerates with a matrix containing tuff or current-bedded sandstones mark the base of the series.

The underlying Tongaporutu beds (39, 45) extend south-east in a broad belt through the basins of the Tongaporutu, Waitara, and Tangarakau rivers. They are lithologically similar to the Urenui and Waitotara beds and, like them, vary considerably laterally. They contain also tufaceous material and inconstant layers of pebbly shell rock. Along the coast 1370 ft. of strata are exposed. Here also there is clear evidence that the underlying Mohakatino beds were uplifted and eroded before the Tongaporutu beds were laid down; south-eastward many contacts were examined and all showed that deposition was uninterrupted. The rocks of the Mohakatino series (39, 45) extend as a continuous belt south-east and south through the Mohakatino, Tongaporutu, and Tangarakau basins. They cover considerable but irregularly distributed areas in the Ohura and Ongarue valleys and outcrop over a relatively narrow coastal strip between the Mokau and Ngukuhakari. They consist chiefly of argillaceous sandstone and mudstone which everywhere contain nests and streaks of andesitic tuff. Along the coast the andesitic material is abundant and beds of breccia occur in places. There are also lenses of fomaniniferal limestone, all more or less tufaceous, at several horizons. The series has a maximum thickness of 600 ft. In the coastal region one angular unconformable and several irregular disconformable contacts with the underlying Mokau beds occur. In the Ongarue and Ohura valleys basal conglomerates containing pebbles of mudstone, and sandstone and rolled concretions rest on an eroded surface of Mokau rocks. But in the southern part of their exposure Mohakatino rocks grade downward without break. North of the Mokau, they overlap the underlying Tertiary strata and rest on Mesozoic rocks. The Mokau beds (39, 45) occupy a large area in the basins of the Mokau and several branches of the Wanganui. In the Mokau valley, where the sequence is best shown, 400 ft. of slightly argillaceous sandstone in massive layers is overlain by 200 ft. of sandstones and shales containing coal-seams; on them rest well-bedded argillaceous sandstones 1000 ft. or more thick. In the Ohura and Tangarakau valleys the coal-measures contain thick and extensive layers of conglomerate and there are pebble bands in the upper sandstones exposed along the Tangarakau gorge. In several localities the lower Mokau sandstones are interbedded with and grade downward into the underlying Mahoenui beds. In the Awakino valley a thin coal-seam at the base of the series shows that terrestrial conditions prevailed during part of lower Mokau time. Over a considerable area in the Ohura and Ongarue basins the lower Mokau sandstones and the coal-measures are absent and the upper sandstones overlap on to an irregular surface of Mahoenui mudstone. Near Te Kuiti also the coal-measures are absent; no contact between the Mahoenui and Mokau was observed, but the upper Mokau sandstones overlap on to the Te Kuiti beds and Mesozoic rocks. At several points at the southern end of the Herangi Range also they rest directly on the older mass. South of Port Waikato there is a small isolated area of sandstone called the Waikawau series (42) that almost certainly corresponds with the upper part of the Mokau beds. It rests with evident discon-formity on Mahoenui claystones.

Strata referred to the Mahoenui series (39, 42, 45) cover considerable areas in the Awakino, Mokau, and Ohura valleys and extend north to Waitomo. They consist chiefly of mudstone and argillaceous sandstone, though extensive bands of limestone are known, at the top of the series in one locality and at the bottom in two. In the upper Ohura valley the series is at least 1400 ft. thick, but westward in the Awakino though not reduced by erosion it contains but 600 ft. of strata. In this locality the Mahoenui beds rest with angular unconformity on the Te Kuiti rocks and also overlap on to the Mesozoics. Near Waitomo there is good evidence of disconformity but elsewhere in the Te Kuiti-Awakino district no evidence of erosional break has been observed. North of Raglan Harbour, where a considerable area of Mahoenui beds occur, the contact with the Te Kuiti beds is in places disconformable. The Te Kuiti beds (39, 42) cover large areas in the upper basins of the Awakino and Mokau whence they extend north along the coastal uplands to Port Waikato. The beds are chiefly limestones and calcareous sandstones and claystones and are up to 500 ft. thick. Wherever older Tertiary rocks are present the Te Kuiti beds follow with complete accordance. But overlap is extensive and over many square miles the limestones rest on the gently undulating surface of truncated Mesozoics with the intervention of a few feet of littoral beds, conglomerate, grit, glauconitic sandstone, carbonaceous shale, or coaly material. In many places only the upper members of the Te Kuiti series are present. The Whaingaroa beds (42) below the Te Kuiti limestone extend from Raglan north to Mercer. They consist chiefly of greensands and calcareous sandstones and claystones. They are 500 ft. or more thick in places but owing to overlap their range in thickness is considerable. Where they do not rest directly on the basal rocks of the district they grade downward with complete accordance into coal-measures. The coal-measures (39, 42) are of two types and were formed under conditions predominantly, either estuarine and fresh-water, or littoral and salt-water. The first type occurs in the neighbourhood of Huntly and consists of grey and yellow semi-refractory clays up to 300 ft. thick which grade upward into, and are interbedded with, the blue clays of the Whaingaroa series. Near the base there are one or more thick seams of coal containing a very small amount of sulphur. The littoral coal-measures are found from Whatawhata to the upper Awakino. They are usually less than 50 ft. thick and consist chiefly of conglomerates, grits, sandstones, and shales, and contain lenticular coal-seams. Shell beds occur rarely and the coal contains several per cent. of sulphur. The coal-measures lie conformably below any member of the Whaingaroa and Te Kuiti beds and range in age from the beginning of Whaingaroa time to the end of Te Kuiti. On the other hand, the fresh-water coals are pre-Whaingaroa in age. On palaeontological evidence the Mokau beds are correlated with the Awamoa beds of the Oamaru district and the Te Kuiti limestone with the Ototara limestone. Fossils are scarce in the Mahoenui beds but from their relation to the Mokau and Te Kuiti beds they are thought to correspond to the Hutchinson Quarry beds of the Oamaru district.

North Auckland. The Batley (19) and Onerahi (41) rocks of North Auckland are older than any of the Tertiary beds of South-west Auckland. The former are chiefly claystones more or less silicified and containing fossils that fix their age as high in the Cretaceous. The overlying Onerahi beds are claystones, argillaceous limestones, greensands, and conglomerates; the most characteristic rock being the argillaceous limestone usually known as the “hydraulic limestone.” There is no doubt as to the position of these rocks in the sequence but their age is not agreed upon. Unconformably overlying the Onerahi series are accordant sets of beds consisting in upward sequence of (a) quartz grits, conglomerates, and shales with coal-seams, the whole from 30 to 100 ft. thick; (b) argillaceous and glauconitic sandstones from 300 to 500 ft. thick; and (c) limestone and calcareous sandstone up to 300 ft. thick. The limestone is usually known as the Whangarei limestone. Though this group of beds is separated from any outcrop of the Te Kuiti limestone and the strata accordantly underlying by many miles of country where no outcrops of these formations occur, there is not the slightest doubt that they are the same. The sequence of lithologically similar strata correspond, and both sets rest on gently undulating surfaces of older rocks. The Whangarei coal-measures are analogous to the marine facies of the Te Kuiti coal-measures. The palacontological data lend decided support. A widespread series of feldspathic sandstones up to 1200 ft. thick and known as the Waitemata beds (14) overlies the Whangarei limestone. These sandstones are interbedded with bands of mudstone and lenses of conglomerate and in their upper part contain much fine andesitic material, in places grading into breccia. The whole series is evidently of shallow-water deposition. Some observers consider that there is a disconformity between the higher tuff-containing beds, which are known as the Parnell grits, and the main mass of the sandstone, and others that the tuffs are equivalent to the well-known Waitakerei breccias. The Waitemata beds are unconformable to the rocks on which they were deposited and rest in turn on the Whangarei, Cretaceous, and pre-Cretaceous formations. They are correlated without much doubt with the Mokau beds, which also belong to a predominantly sandstone, shoal-water series. The Parnell grits have their counterpart in the tufaceous Mohakatino beds. The thick series of conglomerates, sandstones, mudstones, and tufaceous andesitic material of the North Cape district, known as the Coal Point beds (25), are probably of Waitematan age. Richly fossiliferous tufaceous sandstones outcrop over a small area near Pakaurangi Point (6), Kaipara Inlet. They lie unconformably on Cretaceous strata but their relation to the Whangarei and Waitemata beds has not been observed. They are, however, undoubtedly closely connected with the latter which they underlie, whether conformably or not is uncertain. The contained molluscs indicate an age between the Ototaran and Awamoan, but since the typical Hutch-insonian fossils are mainly brachiopods they are not comparable with those of Pakaurangi Point. These beds, however, are tentatively placed in the Hutchinsonian. The basal Waitemata beds of Waiheke Island also contain Hutchinsonian fossils (A. W. B. Powell).

East Cape — Hawke Bay District. Cretaceous and Tertiary rocks form most of the broad strip of undulating, hilly, and moderately elevated country lying between the east coast and the axial range of the North Island and extending from East Cape to Hawke Bay. Now that most of this area has been geologically examined in detail it is possible to attempt the correlation of the rocks with those in other parts of New Zealand. There are two main groups of strata separated by an unconformity marking long continued erosion (52). The first group consists essentially of Cretaceous and possibly early Tertiary rocks; the second of those of Miocene and Pliocene age. The Cretaceous sequence seems to be more complete here than elsewhere in New Zealand. Not only do the beds of the wide-spread Senonian transgression outcrop, but somewhat older sediments also occur, deposited before this transgression during the period while most of the area now occupied by New Zealand was land uplifted by the Hokanui orogenic movements. Explorations have not yet extended west far enough definitely to prove that the lowest of the Cretaceous rocks are of pre-Hokanui age. The Cretaceous strata are divided into the Mangatu, Taitai, Tapu-waeroa, and Raukumara series. The Mangatu beds (44) contain sandstones, shales and mudstones of several colours, greensands, and thick conglomerates; but the most conspicuous member is the argillaceous limestone at the top of the series. The beds have a maximum thickness of 4000 ft. or more, and will probably be subdivided on further work. Fossils are rare, but are sufficient to show that the lower beds are of Senonian age. The argillaceous limestone is correlated on lithology with the hydraulic limestone of the Onerahi series and the underlying members roughly correspond to the Batley beds. The Taitai rocks (44), which are indurated conglomerates and sandstones, in places separate the Mangatu and Tapuwaeroa series. But the original position of the beds is in doubt and some geologists believe them to be rocks of pre-Raukumara age thrust into their present position by great earth-movements. They contain no determinable fossils. The Tapuwaeroa rocks (44) consist chiefly of black carbonaceous shales interbedded with thin bands of sandstone, of light coloured shales, and of conglomerates, the whole being about 3000 ft. thick. Where the Taitai sheet is not present the separation of the Tapu-waeros from the overlying Mangatu beds is difficult. Fossils are scarce and the age of the beds cannot be precisely fixed. The basal beds contain a few fossils which are perhaps of Turonian age. Unconformably below the Tapuwaeroa beds are alternating sandstones and mudstones much jointed and so indurated as to approach greywackes and argillites. These, the Raukumara beds (44), are over 5000 ft. thick. In their upper part is a massive blue mudstone, known as the Mangaotane mudstone and up to 1500 ft. thick. Different sections show different thicknesses of this mudstone and in places it is absent, presumably eroded before the beds above it were deposited. The few fossils present indicate that the upper part of the series is of Albian age and correlative with the Clarence beds of Marlborough.

In the future the Raukumara beds will probably be divided into several series. The Tertiary rocks exposed between East Cape and Hawke Bay consist chiefly of mudstones and argillaceous sandstones, though limestones, conglomerates, and layers of tuff are also present. The rocks evidently accumulated rapidly under relatively uniform conditions and are so thick (33,000 ft.) as to suggest deposition in a geosynclinal trough that sank as the neighbouring land, supplying the sediments, rose. Several intervals of erosion have been recognised; most of them are represented by disconformities, though angular discordance is shown in some sections. South from the latitude of Gisborne the strata have a small regional dip toward Hawke Bay so that younger beds tend to outcrop in that direction. The sequence in descending order is as follows: Series. Age. Petane beds, 1200 ft.+ Nukumaruian Waihua beds, 3000 ft.+ Waitotaran Ormond & Tokomaru beds, 5400 ft. Taranakian Opoiti beds, 4200 ft. Mapiri beds, 10,000 ft. Morere beds, 900 ft. Tutamoe beds, 4500 ft. Awamoan Ihungia beds, 3500 ft. Hutchinsonian Wheao beds, 2000 ft. + Eocene (?) Several of these series are so poor in fossils that they cannot by them be correlated with strata in other parts of New Zealand. But the Petane beds are probably of Nukumaruian age, the Waihua beds Waitotaran, and the Tutamoe beds, Awamoan. The Petane beds (15, 30), which outcrop west and south of the down-warped area occupied by Hawke Bay and the Heretaunga Plain, are predominantly shoal-water beds. They consist of sands and mudstones, pebbly limestone, and shell rock. The beds grade laterally into one another and contain much pumiceous material. One section shows 1200 ft. of strata, but the series is probably considerably thicker. Palaeontological evidence is strong that part of the series is of Nukumaruian age, but it is likely that more field-work will show that stages missing at Wanganui are here represented. In the East Cape district a small patch of sandstone unconformably above Miocene strata outcrops in the Wharekahika valley (44). These are correlated with the Nukumaru beds but the evidence is not conclusive. North of Hawke Bay the Waihua beds (48) occupy the southern end of the Wairoa syncline. They consist chiefly of alternating layers of argillaceous sandstone and mudstone; bands of coarse pebbly sandstone and shell rock indicate shallower water at several horizons. The strata, which are more than 3000 ft. thick, are correlated with the Waitotara beds. The thick Ormond-Tokomaru Series (5400 ft.), Opoiti Series (4200 ft.), and Mapiri Series (10,000 ft.) (48) are shallow water beds containing a large amount of tufaceous material at several horizons. The strata of this group outcrop north of Hawke Bay and the younger series of the group extends north of East Cape (37, 44). Lateral

gradation from one rock type to another has been noted in many localities and at different parts of the sequence. Many conglomerate bands and layers of shell rock are known and several disconformities and unconformities; the break at the base of the group is widespread. The series recognised are not of the same thicknesses throughout owing to erosion, overlap, or differences in conditions of deposition in different localities. This group of series occupies the same position in the sequence of the east coast as the Taranaki group of the west coast of the North Island. The palaeontological evidence does not contradict this correlation and supports it in that the faunas on cach group are at about the same stage of evolutionary development. At the same time precise correlation of the beds on the east and west coasts cannot be made, perhaps because the same stages are not present, or have not yet been found, on both sides of the island. Probably there are several stages in the vast thickness of strata north of Hawke Bay not represented in Taranaki. Tutamoe rocks (44, 48) cover irregular but considerable areas between Hawke Bay and East Cape. They consist chiefly of alternating beds of argillaceous sandstone and mudstone; volcanic tuff, acidic in composition, is present in large amount throughout the whole area occupied and in some localities there are extensive layers of conglomerate. The beds are thickest in the southern part of their exposure (5000 ft. or more); northward they thin to less than 2000 ft., perhaps owing to overlap on the Ihungia beds, which underlie unconformably, or to erosion before the unconformably overlying Tokomaru-Ormond Series were deposited. The Tutamoe beds as a whole are poorly fossiliferous but the shells that occur are with little doubt of Awamoan age. The Ihungia beds (44, 48) outcrop throughout the same general region as the Tutamoe strata. They are largely mudstone but in many localities there is a conglomerate of igneous pebbles, and at fewer points an andesitic tuff, near their base. Twenty miles north-west of Gisborne these beds rest unconformably on the Wheao beds, an older Tertiary formation, but northward overlap on to rocks of Cretaceous age. Fossils are not numerous and are least scarce in the basal conglomerates. They indicate a Hutchinsonian age for the Ihungia beds. The Wheao beds (37), which have been recognised in one locality only, consist chiefly of much jointed and rather indurated sandstones, though mudstones and conglomerates also occur. They are 2000 ft. or more thick and are unconformable to the underlying Mangatu beds. Fossils are rare and are insufficient to fix their age. Pumiceous sands and silts, not strongly consolidated and in places containing lignite beds, occur in the Waipaoa valley and the Whare-kahika graben. They contain a few fossils that indicate a Castlecliffian age for this, the Waipaoa Series (37, 44). The Castlecliff beds at Wanganui also contain much pumiceous material. The Wharekahika graben was almost certainly formed during the Kaikoura deformation. New Zealand, after this orogeny, was elevated as a whole as well as differentially; still later depression allowed the Waipaoa beds to accumulate in the drowned lower valley of the Waipaoa and in the Wharekahika depression. The Castlecliff beds at Wanganui are, so far as known, the only open coast beds of the post-Kaikoura depression.

Hawke Bay—Palliserbay District. The Hawke Bay—Palliser Bay district was explored by the old Geological Survey, but except for a few hurried visits by different geologists and some detailed work by the staff of the Taranaki Oil-fields, of which the results have not been published, no examinations have been undertaken in this area for many years. Some of the old Geological Survey collections of fossils have been examined as well as some made in later years, but very little is known of the distribution of the rocks of the different series. South from Waipawa, Cretaceous rocks extend for a hundred miles or more, forming a strip of greater or less width along the coast. A limestone, lithologically similar to the Mangatu limestone of the Gisborne district and the Amuri limestone of the South Island, is present at many points, and under it are shales and greensands. Some beds contain ammonites or Inoceramus and all are much crumpled and shattered. The oldest Miocene rocks definitely identified by means of fossil collections are of Tutamoe age (Awamoan), but some of the underlying mudstones in which no fossils have yet been found are undoubtedly Hutchinsonian, and strata of the same age as the Wheao beds may be present; but rocks of Ototaran and Taranakian age are not known. Strata of Waitotaran age, the Te Aute limestone and associated beds (22), are widely distributed from Hawke Bay to Palliser Bay. They rest unconformably on Cretaceous and older rocks as well as on strata of Miocene age. At many points the Te Aute limestone is formed of shell fragments and contains pebbles and grit attesting its shallow water origin. Strata equivalent to the Petane beds (15), of Nukumaruian age, are known at several points and seem to be nearly as widespread as the Te Aute limestone. The Patangata gravels and sands (30) west of Cape Kidnappers are thought to be of the same age as the Waipaoa Series and, like it, contain pumice. Some of the gravels of the Ruatangata plain and the Wairarapa depression are probably of the same age (Castle-cliffian). Tertiary Igneous Rocks of the North Island. Crustal stresses may be relieved in part by earth-movements and in part by the intrusion of dykes and the extravasation of lavas. Thus igneous rocks furnish important evidence in geological history and their study is second only in importance to that of the sediments. At many points in North Auckland basic and ultrabasic rocks, generally now greatly altered, intrude Onerahi and older sediments but not those of Whangarei age (25, 41). They were probably therefore intruded in the Eocene and are thought to be connected with the stresses that shattered the Batley and Onerahi beds of North Auckland and the rocks of equivalent age elsewhere. The serpentine outcropping near the Wairere falls of the Mokau (39) is correlated with the basic intrusions of North Auckland. About the same age and probably the surface representatives of the deeper seated norites, epidiorites, and serpentines of North Auckland are the gabbros and basaltic flow and fragmental rocks that

cover considerable areas in the basin of the Northern Wairoa (Tangihua Series) and in the North Cape district (Whangakea Series (25)). These rocks are in places altered and crushed and the breccias are well consolidated. With them are correlated the similar rocks of the Makakaoa Series (44) of the East Cape district, probably the teschenites of Brancepeth (East Wellington) and, doubtfully, the basic rocks of Red Island, south of Cape Kidnappers. The Parahaki Series (41) of the Whangarei district consisting chiefly of lavas, tuffs, and dykes of acid composition, are, rather doubtfully, post-Onerahian and pre-Ototaran in age. Since in some igneous provinces acid and basic eruptions follow one another after comparatively short intervals, or even alternate, the Parahaki and Tangihua rocks are interpreted as differentiates from the same magma separated by but a short interval of time. The earth-movements which caused the Hutchinsonian transgression were accompanied by eruptions of andesitic material in North Auckland and in the East Cape district where tuff occurs respectively in the basal Pakaurangi (6) and Ihungia (44) beds. Volcanoes were again active in North Auckland toward the end of Waitemata time when the andesitic tuffs and breccias forming the Parnell grits and occurring in the upper Waitemata beds of other localities were ejected. Activity was renewed at the close of Waitemata time on a much larger scale when the rocks of the Manukau and Wairakau (31) series were formed. By common consent the andesitic breccias of the upper part of the Hauraki andesites are correlated with the Manukau breccias and the Wairakau Series, chiefly on the similarity in composition of the rocks and on the fact that all are of post-Whangarei age. The Hauraki eruptions were long continued and probably different parts of the vast pile there accumulated are of the same age as rocks of the Pakaurangi, Parnell, and Manukau-Wairakau series. The andesitic masses of Orangiwhao, Moeatoa, and Whareorino (39) hills in South-west Auckland are probably the roots of volcanoes that furnished the tuff and breccia of the Mohakatino beds. If the correlation of these rocks with the Parnell grits be correct, volcanic activity began later in South-west Auckland than in North Auckland. The origin of the sprinkling of andesitic tuff in the Tongaporutu, Urenui, and Waitotara beds of Taranaki is not known. The vents of South-west Auckland may have been active, but other volcanoes, perhaps in Taranaki or near Tongariro, may well have opened during these periods. The age of the Taranaki volcanic rocks is not definitely known; their outer fringe overlies Waitotaran rocks unconformably (43); and they are considered to range through the younger Pliocene and Pleistocene. The widespread Kerikeri Series (31, 41) of North Auckland consists of basaltic rocks that are obviously closely connected with fractures produced by the Kaikoura deformation. They range in age from this orogenic movement to the Recent. The basalts outcropping south of Auckland between Tuakau and Kawhia (42) are correlated with the similar rocks of the Kerikeri Series. In the east coast region of the North Island volcanic ash of acid composition first appears in the Tutamoe beds (37, 44) and

occurs abundantly in many horizons throughout the Miocene and Pliocene. On the west coast the first marine Tertiary beds to contain pumice are those at Castlecliff (29). In the Rotorua-Taupo district a thick mantle of subaërial rhyolitic tuff (Mamaku Series (49)) completely hides the underlying rocks; but east and west (39, 45) these tuffs are seen to rest on a highly irregular land surface. So far as known the youngest rocks this buried surface is carved from are of Mohakatino age. Nevertheless the land surface is of much later age and is probably that eroded after the general uplift accompanying the Kaikoura orogeny. The pumiceous material of the Waipaoa and Castlecliff marine beds is part of the same showers that, closer to the centres of eruption, formed the Mamaku tuffs. The pumiceous sands and silts of Tauranga and the similar beds forming the downs of the Hauraki and Waikato depressions (42) are the fluviatile and deltaic members of the same period of eruption. At Arapuni the thick tuffs are separated by old eroded land-surfaces into three or more divisions. Probably the ashes were blown from many vents, the ashes from one vent overlapping those from another, and the eruptions as a whole were probably spread over a considerable period. The “wilsonite” of Waihi is probably of the same age as the Mamaku tuffs. Two other older sets of acidic volcanics are known in the Hauraki Peninsula. The basalts of Pirongia are certainly older than some of the Mamaku tuffs, but equally some of the later basalts of the Kerikeri Series are younger (42). So far as known the rocks of Ruapehu, Tongariro, and other andesitic cones of the Taupo-Rotorua district, were erupted after the Mamaku tuffs, though older volcanics may well form the core of the vast masses of Tongariro and Ruapehu. Western and Central Nelson. The Tertiary rocks of Western and Central Nelson occur in areas some of which are more or less connected, though others are entirely separate. Of these the Westhaven, Westport, Inangahua, Brighton, and Greymouth areas are on, or close to, the western coast; the Murchison area, in an intermontane basin, extends north along the Karamea and Takaka fault-angles to Golden Bay; and the Nelson area occupies a wide graben between Tasman Bay and the upper Buller basin. The accompanying table shows the beds present in the several areas and the correlations adopted. The well-known Cobden limestone and the strata conformably below it (Port Elizabeth and Omotumotu beds) form a group of strata, the Greymouth Series, closely comparable to the Whangarei beds and Te Kuiti-Whaingaroa beds of the North Island. This group is readily recognisable in all the coastal areas of Western Nelson (32, 33, 34, 40) but not so certainly in the Murchison basin and the Nelson depression. In many parts the rocks of the Greymouth Series rest on older Tertiary beds but over larger areas the different members overlap on the pre-Tertiary rocks, and in many such areas coal-seams are present on or near the basal rocks; but where the overlap is great, thin layers of conglomerate, sandstone, or shale, separate the limestone members from the pre-Tertiary older mass. That earth-movements

raised the older Tertiary coal-measures before the rocks of the Greymouth Series were deposited is shown by the coal-pebbles in the lower beds of the group in the Greymouth, Hawk's Crag, and Mokihinui districts (1). At Brighton there is angular unconformity between the Greymouth beds and the unfossiliferous breccias of the earliest Tertiary or late Cretaceous. In the Westhaven district the strata of the Westhaven (Greymouth) Series and the underlying older Tertiary are everywhere parallel, but the lower Westhaven beds are of shallow-water or littoral origin and the coal-seams in them show that terrestrial conditions at times prevailed. In the Greymouth district the Kaiata mudstone and Island sandstone, the marine higher beds of the older Tertiary Mawheranui Series are separable, but in the Westport, Reefton, and Murchison districts, though strata corresponding to the Kaiata mudstone are present, the equivalent of the Island sandstone has not yet been recognised. At Westhaven older Tertiary marine beds are absent; in part the fluviatile and estuarine beds of the Pakawau Series may be their equivalents. The marine older Tertiary beds contain fossils sparingly; those in the Island sandstone at Ten Mile Bluff are of Bortonian age (J. Marwick). The Brunner beds of the Greymouth district consist of conglomerates, pebble beds, grits, sandstones, and shales with coal-seams, and are of fluviatile and estuarine origin. With them are correlated the similar beds in the Brighton and Westport districts. Except that the Kaiata mudstone is absent the different members of the Pakawau Series in the Westhaven district closely correspond with those of the Brunner and underlying Paparoa beds; if they are contemporaneous there is a great pre-Ototaran gap in the Tertiary of this locality represented by a disconformity not yet recognised. The coal-measure in the neighbourhood of Reefton and the small area north of Bullock Creek, referred to the Greymouth Series in N.Z.G.S. Bull. No. 18, undoubtedly also belong here. Since the Brunner beds conformably underlie the Bortonian horizon at Ten Mile Bluff, they, in part at least, are equivalent to the Ngapara beds of the Oamaru district. The Paparoa beds of the Greymouth district are fluviatile and estuarine deposits similar to the Brunner beds, but of more limited distribution. They are thought to be equivalent to the lower part of the Pakawau Series and are correlated with the Hawk's Crag breccia of the Brighton, Westport, and Inangahua districts. Similar breccias some miles east of Reefton are probably of the same age; these breccias may, however, be the equivalents of the coarse basal conglomerates of the Brunner beds. The Hawk's Crag breccias are considered to be in great part pluvial deposits derived from fault cliffs formed immediately before, or being formed during, their deposition. The basal conglomerates and sandstones of the Paparoa beds are the material of the breccias transported, rounded, and more or less sorted by streams. The overlying pebble beds, sands, shales, and coal-seams are the valley plain, in part perhaps piedmont plain, deposits of the same streams more maturely developed. Some change in conditions, probably due to land movements, caused the deposition of the basal Brunner conglomerates which in turn were succeeded by the coarse sandstones, and grits of

Correlation of the Younger Rocks of Western Nelson. Age. Greymouth. Brighton. Westport. Westhaven-Takaka. Inangahua-Grey Graben. Murchison. Nelson. Pliocene Wanganuian Old Man Bottom Old Man Bottom Moutere Gravels Brighton Bottom Deltaic Beds Glenhope Beds Plio-Miocene Taranakian Blue Bottom Upper Kongahu Series Blue Bottom Longford Series Miocene Awamoan Blue Clays Coal Measures (Giles, Camp, Moonlight (?) Cks.) Coal Measures (Longford, Matakitaki) Present Miocene Hutchinsonian Terakohe Mudstone Blue Mudstone Mangles Series Present Oligocene Ototaran Greymouth Series Matiri Series (a) Cobden Limestone Cobden Limestone Kongahu Limestone Westhaven and Tata Limestones Cobden Limestone Limestone (Sphinx Rock, Wangapeka Karamea) Present (?) (b) Port Elizabeth Beds Coal Measures (Brighton, Charleston) Coal Measures (Buller Gorge) Coal Measures (Westhaven, Motupipi) Coal Measures (Three Channel Flat, Fletcher Ck.) Coal Measures (Owen, Wangapeka) (c) Omotumotu Beds Eocene Mawheranui Series Maruia Series (a) Kaiata Mudstone Kaiata Beds (b) Island Sandstone Absent Dark Mudstone (c) Brunner Beds (Coal measures) coal Measures (Fox River) Brunner Beds (Coal measures) Pakawau Series Coal Measures (Reefton) Coal Measures (Maruia) Danian Senonian Paparoa Series Breccia Hawk's Crag Breccia Breccia Breccia

the Brunner coal-measures. The Brunner beds overlap the Paparoa beds and outcrop over much wider areas; the Brunner coal-measures are the deposits of piedmont or coastal plains. The uniformly low sulphur content, less than .5 per cent., of the Paparoa coal indicates their fresh-water origin just as the several per cent. of sulphur in the Brunner coals shows their brackish or salt-water origin; it should be noted that the sulphur content increases the nearer the seams approach the marine members of the Mawheranui Series. Blue calcareous claystones, the Blue Bottom, overlie the Cobden or other equivalent of the Ototaran limestone of the West Coast, in most localities with complete accordance, and overlap on to the older mass at many points. The earth-movements which brought about the change of sediments are, however, marked by unusual deposition at two known points (34). North of Greymouth, in the Punakaiki valley, a mile or so from the coast, a coarse sandstone containing coal-pebbles overlies the Cobden limestone accordantly; here also, as in some other localities, the Blue Bottom contains innumerable particles of coal. Near Reefton, in the Waitahu valley, there is a blended angular unconformity between the Brunner beds and the Blue Bottom; here the Greymouth Series is absent, and perhaps this area was land throughout Greymouth time. In the Greymouth district the Blue Bottom is in places probably more than 1200 ft. thick, but the area over which the claystones outcrop is masked by gravels and exposures are relatively small and discontinuous. The Blue Bottom contains lenses of foraminiferal limestone, shell beds, and glauconitic layers which may mark breaks in the succession. The claystones in their upper part grade into sandstones and are interbedded with layers of fine conglomerate containing thin bands of lignite. The sequence is similar north of the Mokihinui where 1600 ft. of claystone is followed by 600 ft. of coarse sandstones and fine conglomerates containing bands of lignite. Near Cape Foulwind and about Golden Bay only the lower blue claystones are present. Though the wide tectonic valley of the Inangahua is floored with strata overlying the Cobden limestone the beds are so covered with gravels and broken by faults that the full sequence cannot be made out. In parts they overlap the Cobden limestone and, toward their upper part, contain thick coal-seams marking terrestrial conditions and probably equivalent to the lignite seams of the Mokihinui and Greymouth districts. Above the lignites are blue clays which upward are interbedded with the bottom bands of thick blue conglomerates consisting of small, evensized, subangular pebbles of quartzose schist. Fossils are relatively scarce in the Blue Bottom mudstones, though they occur at Terakohe, in the valleys of the Fox and Moonlight streams, at Callaghan's, and elsewhere. They belong to Hutchin-sonian, Awamoan, Taranakian, and possibly Waitotaran horizons. The much weathered and well consolidated Moutere or Old Man gravels unconformably overlie the Tertiary beds described above. They are fluviatile deposits laid down on the eroded surfaces of structural depressions after the general sinking of the land that followed the Kaikoura mountain building period. They are thus correlative with the Castlecliff beds. They outcrop in the Reefton and

Greymouth area, but are not known near Westport or in the Aorere and Takaka tectonic depressions. So far as known the Moutere gravels are nowhere folded or faulted in Western Nelson. The Murchison intermontane basin, which is now being geologically explored in detail, contains many thousands of feet of Tertiary strata (50). These, owing to the sameness of the beds, the paucity of fossils and the difficulties of the country, have not hitherto been satisfactorily subdivided. At least four series are known, separated by disconformities marked by conglomerates containing pebbles and boulders of the underlying Tertiaries and also of the basal rocks of the district. The Maruia Series is the oldest and corresponds to the Mawheranui Series of the West Coast. In places, at the base, is a breccia up to 150 ft. thick; overlying are grits, sandstones and shales with coal-seams, the whole from 35 ft. to 200 ft. thick; above these are dark calcareous mudstones, sandy at the top. These beds correspond respectively to the Hawk's Crag breccia, the Brunner beds, and the Kaiata mudstone. The disconformably succeeding Matiri Series overlaps the Maruia beds and covers larger areas. It consists chiefly of banded sandstones and mudstones, in places calcareous and passing into impure limestone, especially toward the top of the series. The highest calcareous horizons overlap on the Lyell Mountains, and, toward the head of Matiri River, they form part of the limestone sheet, of which fragments occur in tectonic depressions in the upper Wangapeka and Karamea basins, and in the valleys of the Crow, Leslie, and Takaka rivers, and connect finally with the Tata Island limestone. The limestone of Sphinx Rock near Murchison, and that at the head of the east branch of the Owen River, belong to this horizon. The Matiri and Greymouth strata are thought to be contemporaneous. A well-marked disconformity nearly everywhere separates the Matiri Series from the overlying Mangles Series. With the exception of the conglomerate at the base this series consists of banded sandstones and mudstones and is several thousand feet thick. The overlying Longford Series, which has much conglomerate in its lower part, is chiefly banded sandstones, grits, and carbonaceous shales containing coal-seams. The finer detrital rocks make up the upper part of the series, which is about 7000 ft. thick. In the upper part of the Longford beds a calcareous conglomerate contains fossils that indicate a Taranakian age. In the not-yet explored southern end of the depression are conglomerates of schistose material very similar to the deltaic beds of the Inangahua valley; their relation to the Longford beds is not known. The weathered Moutere gravels occupy most of the floor of the Nelson graben from Tasman Bay to the St. Arnaud Range, mountains of quartzose greywacke. The gravels are mostly of the same rock and are in fact the piedmont deposits from the mountains of which this range forms a part; it should be noted that the highlands east and west of the graben are of quite different rocks and supplied but an insignificant amount to the gravels. These deposits, which, so far as known, are not folded or faulted, overlie the conglomerates, sands, clays, and lignites of the Glenhope Series. The pebbles in the conglomerates of these latter beds are of the same igneous rocks that from the adjacent high country east and west of the graben. The

Glenhope beds are upturned near the edges of the lowland, and are there unconformable to the overlying Moutere gravels, but except near the bounding faults they lie flat and grade upward into the greywacke gravels. The Glenhope beds rest on an eroded surface of the older Tertiary strata that outcrop as long, narrow strips, and small patches discontinuously along both edges of the depression. In the strip extending south-west from Nelson the beds are faulted and the sequence is not completely known. At Rocks Road, Nelson, a disconformity, marked by a thin band of shelly conglomerate resting on an irregular eroded surface, separates banded sandstones and mudstones from similar beds that, higher in the sequence, are interbedded with thick conglomerate layers containing small lenses of lignite. The fossils in the shelly conglomerate probably belong to the Hutchin-sonian (J. Marwick). The coal-measures of the Richmond foot-hills are thought to be the oldest Tertiary rocks of this area, and may be Ototaran though the limestone everywhere characteristic of this period seems to be absent. The relation of the coal-measures to the beds at Rocks Road is not known. Another strip of the older Tertiary rocks extends along the western base of the Hope Range. Basal arkositic grits are overlain by greensands, followed by mudstones and argillaceous sandstones many hundreds of feet thick. The fossils suggest Awamoan and Hutchinsonian ages for these beds. In places the sandstones are decidedly calcareous, but the equivalent of the Ototaran limestone seems to be absent; the lenses of high grade foraminiferal limestone occurring in this area resemble the Blue Bottom limestone of the West Coast. There is a disconformity at Tadmor high in the sequence. The sea does not seem to have covered the area of the Nelson graben till late in Ototaran time, perhaps even till the Hutchinsonian. The beds of this transgression were tilted and raised above the sea before the valley plain deposits of the Glenhope Series accumulated. These movements were probably the prelude of the Kaikoura orogeny a deformation that culminated after Glenhope time and raised the mountain mass of which the St. Arnaud Range is a part. The Moutere gravels, the piedmont deposits derived from the highlands then formed, are correlated with the Castlecliff beds, and the Glenhope beds with the Nukumaru beds. Marlborough and North Canterbury. As in Western Nelson, the late Cretaceous and Tertiary rocks of Marlborough and North Canterbury occur in a number of more or less disconnected tectonic depressions. The sediments, however, differ greatly in texture and composition from those of Nelson, and their correlation with them is difficult. The oldest Cretaceous rocks, the Clarence beds (10), outcrop at many points in the Clarence and Awatere valleys, the sequence differing in the several localities. The most complete section is probably at Coverham, in the Clarence valley, where nearly 8000 ft. of strata, consisting chiefly of black mudstone containing calcareous concretions and several thick sandstone bands and having a conglomerate at its base, is exposed. In other sections coal-measures and volcanic

rocks occur in the lower part of the series. Fossils are not abundant but are sufficient to establish that the strata of this series, from top to bottom, are of Albian age. The next group of Cretaceous rocks, the Piripaua Series of upper Senonian age, is not present in the Clarence and Awatere valleys but beds belonging to it outcrop in the Amuri Bluff, Waipara, Malvern Hills, and Trelissick districts, localities where rocks of Clarentian age are not known, and the Senonian beds rest on pre-Cretaceous greywacke. More than 1200 ft. of strata occur at Amuri (27), the lower half consisting of littoral and shallow water marine conglomerates, grits, and sandstones, and the upper half chiefly of greensands, mudstones, and limestones. In the Waipara district (12), where a maximum of about 800 ft. of strata is present, the lower beds contain thin seams of lignite. In the Malvern Hills district (56), where the beds are up to 5000 ft. thick, the coal-measures are important and contain workable seams. Here the bulk of the beds probably belong to the lower half of the succession exposed at Waipara and Amuri. The Amuri limestone (3), the rock next in age above the Piripauan, has provoked a great deal of discussion. The limestone contains a large proportion of very finely divided calcite and in many localities much flint, especially in its lower part. Thomson suggests that both were chemical precipitates, though admitting that the flint in part is secondary. The calcite particles may be analogous to the chemically precipitated calcium carbonate muds of the shallow Florida seas.*T. W. Vaughan: “A Contribution to the Geologic History of the Floridian Plateau,” Carnegie Inst. Publn. No. 133, pp. 99–185 (1910). These muds are amorphous, but the readiness with which calcium carbonate changes its form is well known. If the marine conditions during the deposition of the Amuri limestone were similar to those of the Florida seas or Bahama banks,†R. M. Field: “The Great Bahama Bank. Studies in Marine Carbonate Sediments,” Amer. Jour. Sc., vol. 16, pp. 239–46 (1928). the shallow bottom would have been so frequently agitated by waves that molluscs and other sedimentary or slow-moving marine organisms could not have lived. This would explain the almost complete absence of marine fossils (excluding foraminifera) in the Amuri limestone, except in localities where, as now exposed in the Trelissick basin, volcanic ash for a time was deposited rapidly enough to change radically the conditions on the sea floor. In the Waipara valley (12) the Amuri limestone grades down into a grey calcareous mudstone which lower becomes glauconitic and rests with apparent conformity on the Waipara greensands of Piripauan (Upper Senonian) age. In the eastern part of this district loose sands are interposed between the Amuri limestone and the Waipara greensands. In other localities in Canterbury, where the base of the Amuri limestone is exposed, it is described as grading downward into the Piripaua beds. At most places in the Clarence valley (10) the lower flinty beds of the Amuri Series are parallel with the underlying Clarence beds of Albian age. At the Herring River, however, there is angular unconformity. The Amuri limestone and flints in the Clarence valley are very thick, and Thomson (3) suggests that

their lower flinty facies may be of Piripauan (Upper Senonian) age. On this hypothesis the Cenomanian, Turonian, and part of the Senonian stages would still be missing, for Albian fossils are found a few feet below the Amuri beds. Hence it seems preferable to consider that the Clarence Series is separated from the Amuri limestone by an erosion interval, in most localities marked by an inconspicuous disconformity representing the Cenomanian, Turonian, and most of the Senonian stages. The texture and composition of the Amuri limestone have been fully described (3, 7). In places it becomes clayey or sandy and grades to a mudstone or even to a sandstone. Glauconite, which is sparingly present throughout, in places forms definite bands. Flint nodules occur at many points and in some areas form thick layers at the base of the series. Tuff is interbedded in some localities (4). The Amuri limestone is usually from 150 ft. to 300 ft. thick, but sections no great distance apart show different thicknesses; the extremes are 12 ft. at Gore Bay and 2600 ft. (with the underlying flint beds) in the Clarence valley. These differences in thickness suggest its shallow water origin. The chief pertinent facts concerning the age of the limestone are: (1) It rests on rocks of undoubted Upper Cretaceous age. (2) A fragment of fibrous shell, probably Inoceramus, has been found in the limestone at Amuri Bluff (J. Marwick). (3) Chapman considers the foraminifera it contains to be of Danian age (57). (4) Tertiary shells occur in its upper part (4). (5) At Pahi, its correlative, the hydraulic limestone of North Auckland, appears to overlie greensands of Eocene age (18). From the above Thomson's suggestion that the limestone is a true Cretaceo-Tertiary rock seems to be reasonable, as does his correlation with the Wangaloa and overlying beds of the Kaitangata district. According to this view the top of the Amuri limestone is of late Eocene age. The often-described contact between the Amuri limestone and the Weka Pass stone (7) is regarded as a disconformity. As already stated, the Amuri limestone is thought to be a shallow water deposit; eustatic movements of the strand may have caused the emergence of the limestone which later, by a similar movement, again became sea bottom on which the Weka Pass stone was deposited. Thomson (12) has discussed the palaeontological correlation of the middle and young Tertiary beds of Marlborough and North Canterbury. He established the Hutchinsonian age of the main Mount Brown limestone and, on decidedly weaker evidence, places the lower Mount Brown beds in the Ototaran and the “Grey Marls” and Weka Pass stone in the Waiarekan. He describes an unconformity above the “Grey Marls” and since the Waiarekan is likely to be merged with the Ototaran this unconformity is taken as separating the Hutchinsonian from the Ototaran. The same unconformity has been recently described, at the Hurunui mouth (26) and no doubt corresponds in time with the erosion interval between the beds of Ototaran and Hutchinsonian age occurring in South-west Auckland, Oamaru, Murchison, and the West Coast, and with the widespread overlap of

the Hutchinsonian beds in North Auckland, the East Coast of the North Island, and probably also Nelson. The upper part of the Mount Brown beds, soft sandstones inter-stratified with rubbly limestones and shelly conglomerates of littoral deposition, are of Awamoan age. The lithologically similar Greta beds, unconformably above them, are correlated with the Waitotara beds. In their tipper part the Greta beds contain many pebble bands and much shelly conglomerate and are succeeded by the Kowhai gravels (9) which are locally unconformable to them. Since these gravels, equally with the Greta beds, are tilted, they must have been laid down before the Kaikoura movements ceased. They are therefore correlated with the Glenhope and Nukumaru beds. In Marlborough the thick blue mudstones that form the Awatere beds range in age down at least to the Awamoan but their higher parts may well be of Taranakian or Waitotaran age. The Great Marlborough Conglomerate is probably about the same age as the Kowhai gravels. South Canterbury and East Otago. The late Cretaceous and Tertiary rocks of South Canterbury and East Otago form a more or less continuous strip along the eastern edge of uplands, in which also disconnected patches occur in tectonic depressions. The basal beds are everywhere unfossiliferous conglomerates, grits, and sandstones and between these and the Ototaran limestone, which outcrops in most districts, are strata that differ greatly in thickness and composition in the several areas. No marine beds are known above the Awamoan, and younger stages, if present at all, are represented by terrestrial deposits. At Kaitangata (47) the lowest rocks of the Cretaceous group are coarse greywacke- and schist-conglomerates containing coal-seams and at least 500 ft. thick. These are correlated with the Henley breccia and the Blue Spur “cement.” Farther afield the Bed Bottom of Naseby (46), the lower part of the Horse Range conglomerates (55), and the basal sandstone-conglomerates of the Ngapara beds of Oamaru (36) correspond in position in the sequence. At Kaitangata a fine conglomerate of quartz pebbles overlies the schist-conglomerates with angular unconformity; farther north there is disconformity, and in the Tuapeka district abrupt overlap (35). Fine quartz-conglomerate and quartz-grits overlie the schist and sandstone conglomerates of the other localities mentioned and at some points, as at Mount Somers, and perhaps Waimate, form the basal beds of the younger rock series. These quartz-grits are practically continuous from Kaitangata to north of Waimate. They range in thickness up to 900 ft. and fossiliferous marine beds are known at or near their top in several localities. At Mount Somers, Kakahu, Waimate (24), and Oamaru the fossils are of Eocene age (Bortonian); at Boulder Hill and Wangaloa, Palæocene or topmost Cretaceous; at Shag point and Brighton (17) Upper Cretaceous. The quartz-grits are interpreted as the littoral beds of an extensive sea transgression that began in the late Cretaceous and extended into the Eocene; the underlying schist- and greywacke-conglomerates, which seem to occur in

discontinuous patches are the fluviatile terrestrial beds of the sinking land. The first marine fossils preserved are at the horizons where the highly porous littoral beds give place to the less porous off-shore beds. In the Kaitangata—Green Island district there is 800 ft. of glauconitic mudstone and sandstone between the quartz-grits and the erosion interval below the Ototaran limestone. At Shag Point, Upper Cretaceous grits are separated by 500 or 600 ft. of argillaceous and arenaceous strata from the Hampden beds which Allan (24) correlates with the McCullough Bridge horizon immediately beneath the Waihao limestone of the Waimate district. In the Oamaru district and at Mount Somers the Bortonian beds are about 135 ft. below the Ototaran limestone. In the Waimate district there is about 200 ft. of glauconitic beds between the quartz grits and the Waihao limestone. In a general way from Shag Point northward the quartz-grits are thinner and finer in grain, their top is younger and the beds between them and the Ototaran beds thinner. As already stated, the Island sandstone of the Greymouth district contains a Bortonian fauna; the underlying Brunner beds are therefore correlated with the quartz-grits and the overlying Kaiata mudstone with the marine beds between the quartz-grits and the Ototara beds. The terrestrial Paparoa beds and Hawk's Crag breccia of the West Coast correspond in position and in part no doubt in age to the schist- and greywacke-conglomerates of East Otago. According to McKay (28) the succession in the Shag Point district in downward order is Waiareka tuffs. Onekakara beds 200 ft.+ Moeraki Boulder beds 100 ft+ Lower Greensands 100 ft. Katiki Beach sands 300-350 ft. Grits and Limonitic sandstone 40-100 ft. Horse Range breccias and quartz-conglomerates 0-1500 ft. The limonitic sandstones are Upper Senonian and these with the Katiki Beach beds, which contain saurian remains, and the overlying greensands are no doubt correlative with the Piripaua beds of Marlborough and North Canterbury. The Onekakara or Hampden beds are pre-Ototaran and post-Bortonian and with the Moeraki Boulder beds probably represent, in part at least, the Kaiata mudstone, the Amuri limestone, and the glauconitic mudstones above the Wangaloa beds. Ongley (47) records an erosion interval at the base of the Clarendon (Ototaran) beds of the Milton district, and Park (36) a strati-graphic discordance below the Oamaru limestone. Thomson (53) describes phosphatic surfaces in, but near the base of, the Ototaran limestone of the Waimate, Pareora, and Totara-Raincliff districts. All these breaks are at about the same horizon which also corresponds to the disconformity below the Weka Pass stone, the erosion interval at the base of the Greymouth beds, and with the widespread overlap of this series on the West Coast and their correlatives in North and South-west Auckland. The basic tuffs of the Trelissick Basin correspond in age to the Waiareka tuffs; both were ejected by volcanoes made active by the same stresses as produced the earth-movements

represented by the break in the stratigraphic succession described above. The limestones of Mount Somers, Raincliff, Kakahu, Waimate, and Clarendon are all correlated with the Ototara beds of Oamaru. Beds of Hutchinsonian age have recently been recognised in the Waimate district and the calcareous sandstone of Waikouaiti (8) and Caversham (12A) and the greensand of Naseby may belong to the same stage. The discordance between beds of Ototaran and Hutchinsonian age, widespread throughout New Zealand, is represented by eroded and phosphatized surfaces in several localities in the Oamaru district (53). Strata of Awamoan age are known in the Pareora and Waimate districts and at Dowling Bay (13), near Port Chalmers, as well as at Oamaru. Southland and West Otago. No Cretaceous strata are known in Southland and West Otago, and little can be added to Park's (38) account of the Tertiary rocks. The beds “range from conglomerates and gritstones at the base of the series to limestones and marine clays at the top.” All are fossili-ferous except the basal conglomerates. The Hutchinsonian and Ototaran stages are present, but the Bortonian and Awamoan faunas have not yet been recognised. At Blackmount in the Waiau valley the conglomerates, grits, and sandstones are 4000 ft. thick and near Lake Hauroto, where limestone also is present, the Tertiary beds are 2000 ft. thick. It is probable that Lower Tertiary strata occur in the district. The beds occupy the graben between the Livingstone, Takitimu, and Longwood ranges on the east and the mountains of Fiordland on the west. They occur also in patches along the fault-angle depression between the Kaihiku and Hokanui hills and the metamorphic rocks of Otago. Small areas outcrop in the Southland Plain, at Lake Wakatipu and in the mountains of North-west Otago. The highly calcareous beds, as the Winton and Clifden limestones, are correlated with the Oamaru limestone, as also are the fossil beds of Chatton, Waikaia, and Bobs Cove, Lake Wakatipu. The beds above the Clifden limestone are of Hutchinsonian age (16). Otago Central. Otago Central seems to have been land throughout the whole of the Tertiary. At the close of Ototaran time this area, like the rest of New Zealand, had presumably been reduced to a peneplain. No doubt this and the adjoining sea floor was later at several periods warped, each warping increasing the unevenness of the surface till the present greatly diversified topography resulted. Lakes formed in the hollows and in them deposits accumulated. These (51, 55) consist of clays, silts, and sands usually resting on fine quartz-conglomerates and grits of littoral origin and in many places containing seams of lignite. Overlying these beds and containing fragments from them are thick sandstone gravels and schist-breccias. The schist-breccias are thought to be pluvial deposits from adjacent fault-cliffs formed during the Kaikoura deformation; the sandstone gravels, which are contemporaneous with the schist-breccias, were brought by rivers into

the Otago Central schist area from the greywaeke regions that border it. The sandstone gravels or “Maori Bottom” resemble the Moutere gravels in weathering and degree of consolidation. In places, however, they are faulted and tilted and are therefore correlated with the Glenhope beds and Kowhai gravels. The lake beds contain leaves and a fresh-water mussel. Their precise marine equivalent has not yet been determined, but they are probably of Waitotaran age. Conclusion. The table herewith shows the correlations adopted. Where no line separates the formations, one grades into the other; a broken line indicates that an erosion interval separates series adjoining in the time scale, and a full line that intervening series are absent. The Tertiary and late Cretaceous strata are divisible into three groups on diastrophic grounds. The youngest, deposited after the main Kaikoura movements had ceased, form the Castlecliff beds and their correlatives in other parts of New Zealand. The other and much more important groups were laid down during the relatively quiescent period between the Hokanui and Kaikoura orogenies. The deposits of the older of these groups accumulated during eras of sea transgression and base-levelling following the Hokanui diastrophism, and those of the younger during sea retreat before the Kaikoura diastrophism. The intermittent crustal movements, that had gradually decreased in intensity during the earlier period, increased during the later. For several reasons the erosion interval above the Ototaran beds, now recognised in most New Zealand regions, is taken as separating one group of Feds from the other. First, the Ototaran deposits are the most calcareous of any set of beds. They accumulated when the waste from the land was least, that is when the land was of smallest area and its surface most subdued. The immediately succeeding beds of Hutehinsonian age, though nearly everywhere parallel with the Ototaran, consist chiefly of terrigenous material; evidently when they were laid down a considerable area of sea floor had emerged. Second, the former, the outcropping, and the subjacent extension of Ototaran deposits is greater than that of any other of the younger rock series; that is they were deposited during the period of maximum sea transgression. Third, a great change in the position of the areas where waste accumulated occurred after the close of the Ototaran. The former, the outcropping, and the probable subjacent areas of Ototaran and pre-Ototaran rocks of the younger series is not markedly different in amount in the North and South Islands, whereas rocks of Hutehinsonian and younger age occur predominantly in the North Island. A new cycle of deformation commenced at the close of Ototaran time. The extensive post-Ototaran overlap of the Tertiary rocks on the older mass along the east coast both of the North Island and the northern part of the South may be interpreted as supporting this conclusion rather than as indicating that the general early Tertiary submergence was continuing. The deposits throughout this region are enormously thick compared with contemporaneous beds elsewhere, they are predominantly terrigenous, and they are of shallow water origin from top to bottom, so that the sea floor must have sunk as fast as they accumulated. These facts suggest that during the late

Classification of Tertiary and Late Cretaceous Strata. System and Age. Stage. North Auckland. South-west Auckland and Taranaki. East Cape to Hawke Bay. Hawke Bay to Palliser Bay. West and Central Nelson. Marlborough and North Canterbury. South Canterbury and East Otago. Southland and West Otago. Central. Otago. Wanganui Pliocene Castlecliffian Castlecliff Waipaoa Patangata Moutere Old Man Bottom Veron Maori Bottom Maorl Bottom Nukumaruan Nukumaru Wharekahika Petane Glenhope Kowhai Quartz Grift and Breccias Waitotaran Waitotara Kaawa Waihua Te Aute Inangahua delta beds Greta St. Bathans Taranaki Plio-Miocene Urenuian Urenui Tokomaru-Ormond Opoiti Part of Awatere Tongaporutuan Tongaporutu Mapiri Miocene Awamoan Waitemata waikawau Mokau Morere Tutamoe Present Blue Bottom Upper Mount Brown Awamoa Ocmaru Hutchinsonian Pakaurangi Mahoenui Ihungia Present Lower Mount Brown Hutchinson Quarry Clifden Oligocene Ototaran Whangarei Coal-measures Te Kuiti Whaingaroa Coal-measures Greymouth Gray Marls Weka Pass Otatara Winton Tahuian Onerahi Wheao (?) Present Kaiata Amuri Tahu Hampden Borton Probably Present Eocene Bortonian Upper Mangatu Present Island Sand-stone Danian Wangaloan Brunner Wangaloa Senonian Piripauan Batley Lower Mangatu Present Paparoa Piripaua Conglomerates and Cements Turonian (?) Tapuwaeroan Tapuwaeroa Present Albian Clarentian Upper Raukumara Present Clarence

Tertiary a geosynclinal trough was forming and being filled in this region, whereas, in other parts, and especially in its southern portion, the New Zealand area was intermittently and progressively rising. After the Hokanui deformation the land surface of the New Zealand area was probably greater than now and much diversified both in topography and in outline. Its mountains were a series of ridges forming a great chain, of which the present axial highlands are the roots, fractured and differentially uplifted after the Tertiary base-levelling. The deposits of the first or Clarentian sea transgression, though thick, do not outcrop over large areas, and are chiefly mudstones and argillaceous sandstones, the ill-sorted abundant waste of an extensive elevated land carried to the sea by considerable streams. Land elevation brought this period to a close. The bituminous muds characteristic of the Tapuwaeroa beds are restricted to the east coast of the North Island and seem to have been laid down as mud-flat deposits in extensive inlets or bays not freely open to the ocean. Crustal movements, in places producing fault-scarps, preceded the Waiparan depression that continued through Senonian and Eocene time. Fluviatile conglomerates and pluvial breccias were preserved by burial beneath the littoral and fluvio-marine deposits of the advancing sea. The long-continued depression formed extensive gulfs, in the sheltered waters of which were laid down carbonaceous muds, in places interstratified with sands, and even gravels, from the nearby land. Later, as sinking continued, as the land decreased in area, as its surface became more mature, and as denudation lagged behind weathering, light coloured clays were formed. On open coasts offshore deposits followed by greensands are the characteristic beds of this period. The sheltered-water and the open-water types of deposits are both overlain by a fine-grained, a nearly always more or less argillaceous limestone. The epicontinental shelf was wide and shallow, and in part no doubt fringed by island-remnants of the former land. The conditions favoured evaporation and much carbonate of lime was precipitated. During this long period of depression, which ranged from the late Cretaceous through the Eocene, conditions at any locality changed and with them the deposit there laid down changed also. Breccias and fluviatile conglomerates, terrestrial deposits on lowlands, are found at a few points on the West Coast and in the Waiapu, Malvern Hills, Shag Point, Kaitangata, and probably Southland districts. Littoral or fluvio-marine beds are present wherever rocks of this group rest on the older mass. In parts they are contemporaneous with the terrestrial deposits they cover and overlap, and they range throughout the whole period. The Brunner beds of the West Coast and the quartz drifts of East Otago and South Canterbury are the most distinctive and thickest beds of this type of deposit. Coal-seams are nearly everywhere present in these beds. They are followed either by sheltered-water deposits, characteristically black mudstones, or by off-shore deposits, characteristically blue mudstones and argillaceous sandstones; greensands are present in both types. Sheltered-water deposits are the Batley beds of North Auckland, the bituminous mudstones of the east coast of the North Island, Marlborough, and North Canterbury, the Kaiata mudstone of the West Coast, and the septarian beds near Shag Point. Off-shore

beds occur at Hampden, Waimate, Mount Somers, and elsewhere. The sheltered-water beds in most localities are followed by the fine-grained Amuri limestone. But near Shag Point they are followed by the offshore Hampden beds, and on the West Coast so much fine-grained detritus entered the sea that mudstone continued to be deposited till the close of the period. Widespread crustal movements brought the Waipara period to a close; in parts there was folding accompanied by crumpling and puckering of the soft rocks, and in parts there was a broad warping. About the same time basic rocks were intruded into the crust or poured and thrown out on its surface in the North Auckland, East Cape, East Wellington, and Canterbury districts. The land had been reduced to a surface of low relief during the Waiparan period, the elevation at its close was not great and base-levelling reached its climax in the succeeding Ototaran period. As the land sank the sea transgressed widely on the peneplained surface. Coarse littoral beds followed by finer grained terrigenous deposits form the lower beds, but the upper are everywhere strongly calcareous and these overlap and rest almost directly on the older mass. Coal-seams occur in many localities and chiefly where the lower beds overlap on the pre-Cretaceous rocks. The series as a whole is decidedly thicker on the western side of New Zealand than on the eastern, where in places it is altogether absent; the land was probably down-tilted west during the Ototaran depression. In the Oamaru district, and in parts of Canterbury and Westland, volcanoes, ejecting basic material, were active during the period. Between Ototaran time and the Kaikoura deformation three considerable sets of beds were laid down, the Hutchinson Quarry-Awamoa or Younger Oamaru beds, and the Taranaki and Wanganui (excluding the Castlecliff beds) systems. Each set consists of the deposits of a sea-transgression that closed with uplift greater than that preceding, so that the post-Ototaran as a whole was a period of land emergence. Following from this each series contains detritus from loosely consolidated lower series, and in consequence is thicker and was laid down more quickly than a bed of similar thickness, texture, and composition would have been if formed during a period of general land submergence. The greatest thickness of the post-Ototaran Tertiary beds is along the east coast of the North Island, and there each set and each series of each set outcrops farther from the axis of uplift than that underlying. West of the axial range the Wanganui system in part overlaps the Taranaki beds and in places even rests on the older mass. The Hutchinsonian-Awamoan overlap, though noticeable in most districts in New Zealand, nowhere, except along the east coast of the North Island, extends far past the Ototaran beds. This transgression was broken by uplift in some localities and in others by a pause in depression that allowed the shallow sea-floor of sheltered inlets to be filled to sea-level. Vegetable matter later accumulated and is now represented by the coal-seams of the Mokau, Murchison, Inangahua, and Grey Valley (Moonlight) districts. At the beginning of Hutchinsonian time volcanoes were active in the North Auckland and Waiapu districts and ejected rather basic tuff. During the Awa-moan and especially towards its close much rhyolitic ash was deposited

in the Gisborne—East Cape area and near the end of the period, and after, vents from andesitic magmas opened in South-west Auckland and were especially active in North Auckland and Hauraki. The volcanic rocks of Dunedin (8, 13) and in part those of Banks Peninsula (23) probably also belong to the same age. These eruptions and the warping and uplift of many parts of New Zealand that ended Awamoan time were no doubt the result of the same earth stresses. The succeeding Taranakian depression was most marked in the North Island, where a down-warping of the crust between South Taranaki Bight and Hawke Bay seems to have occurred. Beds of Taranakian age have not yet been definitely recognised in the South Island, but probably parts of the Blue Bottom of the West Coast and of the Awatere beds of Marlborough belong to this period. All the strata of this system were deposited in shoal-water and several erosion intervals divide it into series. Bhyolitic ash is abundant in the beds near Hawke Bay and the vents that emitted the dacitic and older rhyolitic rocks of Hauraki may have opened during this period. The break between Taranakian and Wanganuian time was marked by considerable differential movement in the South Island, for there the beds of the succeeding Waitotaran depression consist largely of conglomerates and sands. There was an extensive Waitotaran transgression over the down-warped southern part of the North Island both east and west of the main range. Volcanic ash of acid composition continued to be laid down in the Hawke Bay area and some of the rhyolitic rocks of Hauraki may be of this age. The main differential movements of the Kaikoura orogeny began in Nukumaruian time and continued after it. The Nukumaru beds of Wanganui and the Petane beds of Hawke Bay were probably deposited on relatively depressed areas. In the South Island the Great Marlborough Conglomerate, the Glenhope beds, the Kowhai beds, and some of the gravels of Otago Central belong to this period. But great movements continued after their deposition and the climacteric deformation was later. The post-Ototaran movements were more pronounced in the South Island than in the North, where volcanic outbursts seem to have relieved the crustal stresses in part. Toward the close of the Kaikoura deformation vents discharging basaltic material opened along a line extending from Kawhia to Whangaroa and activity in this zone continued intermittently until the Recent. The paroxysmal rhyolitic outbursts of the Rotorua-Taupo region began apparently somewhat later than the first emissions of basalt. The tuff, borne far and wide in the air and deposited on a greatly diversified land surface, was still more widely distributed by streams, which carried fine ash and pumice fragments to distant tectonic depressions and to the sea. The practically flat Castlecliff beds, which are the deposits of a minor sea-transgression, contain much pumice in their lower parts as well as a seam of lignite. From these facts and from their fossil content they are correlated with the horizontal, pumiceous, and lignitiferoua Waipaoa beds occurring in the Wharekahika graben and other depressions of the Bast Cape district. The Patangata gravels of Hawke Bay contain much pumice and overlie beds of Nukumaruian age. In the South Island well-weathered, and for the most part, undisturbed

gravels occurring in tectonic depressions, laid down tinder conditions no longer existing, and older than the Pleistocene glaciation, are considered to be of approximately the same age. List of Literature. Transactions of the New Zealand Institute. (1) P. G. Morgan: “Unconformities in the Stratified Rocks of the West Coast of the South Island.” Vol. 46, pp. 270–78 (1914). (2) J. A. Thomson: “On Stage Names applicable to the Divisions of the Tertiary in New Zealand.” Vol. 48, pp. 28–40 (1916). (3) J. A. Thomson: “The Flint-beds associated with the Amuri Limestone of Marlborough.” Ibid., pp. 48–58. (4) R. Speight: “The Stratigraphy of the Tertiary Beds of the Trelissick or Castle Hill Basin.” Vol. 49, pp. 321–56 (1917). (5) J. A. Thomson: “Diastrophic and other Considerations in Classification and Correlation, and the Existence of Minor Diastrophic Districts in the Notocene.” Ibid., pp. 397–413. (6) P. Marshall: “Geology of Central Kaipara.” Ibid., pp. 433–50. (7) R. Speight and L. J. Wild: “The Stratigraphical Relations of the Weka Pass Stone and the Amuri Limestone.” Vol. 50, pp. 65–93 (1918). (8) J. A. Thomson: “On the Age of the Waikouaiti Sandstone, Otago, New Zealand.” Ibid., pp. 196–97. (9) R. Speight: “The Older Gravels of North Canterbury.” Vol. 51, pp. 269–81 (1919). (10) J. A. Thomson: “The Geology of the Middle Clarence and Ure Valleys, East Marlborough, New Zealand.” Ibid., pp. 289–349. (11) P. Marshall and R. Murdoch: “The Tertiary Rocks near Wanganui.” Vol. 52, pp. 115–28 (1920). (12) J. A. Thomson: “The Notocene Geology of the Middle Waipara and Weka Pass District, North Canterbury, New Zealand.” Ibid., pp. 322–415. (12A) L. I. Grange: “An Account of the Geology of Green Island Coalfield.” Vol. 53, pp. 157–74 (1921). (13) H. J. Finlay and F. H. McDowall: “Fossiliferous Limestone at Dowling Bay.” Vol. 54, pp. 106–14 (1923). (14) J. A. Bartrum: “The Geology of the Riverhead-Kaukapakapa District, Waitemata County, Auckland.” Vol. 55, pp. 139–53 (1924). (15) J. Marwick: “Palaeontological Notes on some Pliocene Mollusca from Hawke's Bay.” Ibid., pp. 191–201. (16) H. J. Finlay: “Preliminary Note on the Clifden Beds.” Ibid., pp. 534–38. (17) O. Wilckens: “Lahillia and some other Fossils from the Upper Senonian of New Zealand.” Ibid., pp. 539–44. (18) P. Marshall: “The ‘Hydraulic Limestones’ of North Auckland.” Ibid., pp. 617–18 (1924). (19) P. Marshall: “The Upper Cretaceous Ammonites of New Zealand.” Vol. 56, pp. 129–210 (1926). (20) J. Marwick: “Molluscan Fauna of the Waiarekan Stage of the Oamaru Series.” Ibid., pp. 307–16. (21) L. I. Grange: “Geology of Upper Waitotara Valley, Taranaki.” Ibid., pp. 331–36 (1926). (22) J. A. Thomson: “Geology of Fossil Localities near Waipukurau, Hawke's Bay.” Ibid., pp. 347–54. (23) R. Speight: “Stratigraphical Position of the Charteris Bay Sandstone.” Ibid., pp. 361–63. (24) R. S. Allan: “The Geology and Palæontology of the Lower Waihao Basin, South Canterbury, New Zealand.” Vol. 57, pp. 265–309 (1927). (25) J. A. Bartrum: “Pillow-Lavas, Peridotites, and Associated Rocks of Northernmost New Zealand.” Vol. 59, pp. 98–138 (1928). (26) R. Speight and G. Jobberns: “A Definite Break in the Tertiary Sequence in North Canterbury.” Ibid., pp. 213–31.

Reports of Geological Explorations. (27) A. McKay: “Report on Kaikoura Peninsula and Amuri Bluff.” No. 9, pp. 172–84 (1875). (28) A. McKay: “On the Young Secondary and Tertiary Formation of Eastern Otago—Moeraki to Waikouaiti.” No. 18 pp. 1–23 (1887). (29) J. Park: “On the Geology of the Western Part of Wellington Provincial District.” Ibid., pp. 24–73. (30) A. McKay: “On the Geology of East Auckland and the Northern Part of Hawke's Bay.” Ibid., pp. 182–219. Geological Survey Bulletins. (31) E. Dec. Clarke: “The Geology of the Whangaroa Subdivision.” No. 8 (1909). (32) P. G. Morgan: “The Geology of the Greymouth Subdivision.” No. 13 (1911). (33) P. G. Morgan and J. A. Bartrum: “The Geology of the Buller-Mokihinui Subdivision.” No. 17 (1915). (34) J. Henderson: “The Geology of the Reefton Subdivision.” No. 18 (1917). (35) P. Marshall: “The Geology of the Tuapeka District.” No. 19 (1918). (36) J. Park: “The Geology of the Oamaru District.” No. 20 (1918). (37) J. Henderson and M. Ongley: “The Geology of the Gisborne and Whatatutu Subdivisions.” No. 21 (1919). (38) J. Park: “The Geology of Western Southland.” No. 23 (1921). (39) J. Henderson and M. Ongley: “The Geology of the Mokau Subdivision.” No. 24 (1923). (40) M. Ongley and E. O. Macpherson: “The Geology of the Collingwood Subdivision.” No. 25 (1923). (41) H. T. Ferrar: “The Geology of the Whangarei—Bay of Islands Subdivision.” No. 27 (1925). (42) J. Henderson and L. I. Grange: “The Geology of the Huntly-Kawhia Subdivision.” No. 28 (1926). (43) P. G. Morgan and W. Gibson: “The Geology of the Egmont Subdivision.” No. 29 (1927). (44) M. Ongley and E. O. Macpherson: “The Geology of the Waiapu Subdivision.” No. 30 (1928). (45) L. I. Grange: “The Geology of the Tongaporutu-Ohura Subdivision.” No. 31 (1928). Annual Reports of the Geological Survey. (46) J. Henderson: “Notes on the Geology of the Naseby District.” No. 17 (1923). (47) M. Ongley: “Kaitangata Subdivision.” Nos. 18, 19 and 20 (1924–26). (48) M. Ongley: “Wairoa Subdivision.” No. 22 (1928). (49) L. I. Grange: “Rotorua-Taupo Subdivision.” Ibid. (50) H. E. Fyfe: “Murchison Subdivision.” Ibid. New Zealand Journal of Science and Technology. (51) P. G. Morgan: “The Tertiary Beds of Central Otago.” Vol. 3, pp. 29–33 (1920). (52) M. Ongley: “Cretaceous and Tertiary Formations: A Study of Unconformity.” Vol. 7, pp. 107–17 and 171–80 (1924). (53) J. A. Thomson: “Marine Phosphate Horizons.” Vol. 8, pp. 143–60 (1926). (54) J. Marwick: “Cretaceous Fossils from Waiapu Subdivision.” Ibid., pp. 379–82. Miscellaneous Publications. (55) A. McKay: “Older Auriferous Drifts of Central Otago.” Parl. Paper, C.-4 (1894). (56) R. Speight: “The Geology of the Malvern Hills.” Memoir No. 1, Dept. Sci. and Industr. Research (1928). (57) F. Chapman: “The Cretaceous and Tertiary Foraminifera of New Zealand.” N.Z.G.S. Palaeont. Bull. No. 11 (1926).