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Clinton Series. —The Clinton Series of beds, containing fossiliferous greywacke, at Clinton consists mainly of greywacke beds, some fine like the Tuapeka greywacke, many coarse, green, spotted red, and slicken-aided red. The thick conglomerate bed at Clinton below the fossiliferous bed consists of wellrounded pebbles and boulders of greywacke. porphyrite, and granite from £ in. up to 3 ft. through, forming a bed 150 ft. thick. For a mile across the strike on each side of this bed the greywacke contains frequent beds of coarse igneous and greywacke conglomerate standing vertical, and these are included in the Clinton Series, which is accordingly 10,000 ft. thick. The fossils from Clinton have been described by Dr. Marwick in the Journal of Science, Vol. 7. No. 6, pp. 362-64, 1925, and classified as Permian or Carboniferous. The upper and lower beds included in the Clinton Series show no evidence of their age. Kaihiku Series. —If the name Kaihiku Series is kept for the formation containing the. fossiliferous beds at Kaihiku Gorge and its equivalents and if its base is the thick coarse conglomerate at the front of the Kaihiku Range then the Kaihiku Series includes siliceous greywacke, flinty argillite, slaty greywacke, sandstone, and many beds of conglomerate. These beds form the northern front of the Kaihiku Range and continue as far as the subsequent eastward-flowing courses of the Kaihiku and Puerua Streams. They thus extend a mile and a half across the strike, and are 7,000 ft. thick. These beds stand nearly vertical and strike south-east along the range. They appear as a simple set, but the overturned and shattered parts may be broken by strong bedding faults. Large lumps of an oyster-bed half a mile outside the subdivision at the right-angle bend of Puerua River indicate either that there are two different oyster-beds one high in the sequence described at Roaring Bay and the other in Puerua Valley, not the same, as McKay said, but low in t he sequence, or that if the oysterbed is repeated so as to bring the high Roaring Hay oyster-bed down close to the Kaihiku beds at Puerua then the structure cannot lie simple, as it has been described by McKay, Cox, Park, &c. Dr. Marwick has identified many fossils including : Daonella indica Bitt. ; Rhynconella nuggetensis Wilck. ; Halorella zealandica Trech. ; Dielesma zelandica Trech. ; Spiriferina kaihikuana Trech. ; Spirifernia fragiUs Schlotheim ; Mentzeliopsis spinosa Trech. ; Spirigera kaihikuana Trech. ; Cyrlona trechmanni Wilckens ; and has assigned the beds to the Ladino-Carnic part of the Middle Trias. Oreti Series. —Correlated with the beds in Oreti River described by Cox in 1878 under the name of the Lower Wairoa Series, and renamed by Hector the Oreti Series, is a set of beds of greywacke, fine siliceous greywacke, and flint, and also beds of line conglomerate lying above the beds with the Kaihiku fauna and below the beds with Maoria problematica. Along Waiwera Stream the beds dip at 80° for 60 chains and are thus I,oooft. thick. Between the Kaihiku fossiliferous beds and the Oreti fossiliferous beds occur beds of coarse conglomerate containing worn and angular pieces of mudstonc, and pebbles of greywacke derived from the under-beds. In Waiwera River the upper Kaihiku beds are contorted and shattered and the Oreti flint beds are strong and unbroken and stand vertical. It appears to be a sedimentary erosion contact subsequently disturbed by bedding thrusts. Among the fossils from the beds classed in the Oreti Dr. Marwick has identified : Halobia zitteli var. zealandica Trech. : I Jlokonuia sp. ; Gonodon mellingi as of Wilck. not Zittel ; Nuggetin morganiana Wilck. ; Pleurophorus zealandicus Trech. As the fossils from the Oreti beds of Oreti River were listed by Treclitnann as three doubtful brachiopods without a single positive identification, the beds here classed as Oreti are so classified on their position, not on their fossils: until the type Oreti is better known this con-elation will serve. Trechmann placed the Oreti in the lowest Carnic. Wairoa Series. —Owing to the confusion in the use of the name Wairoa Series and the lumping into it of beds that are distinct stratigraphically and have different faunas, it is here subdivided into — Warepa Series (Pseudomonotis richmondiana beds), overlying Otamita Series (Maoria problematica beds). Otamita Series. —Trechmann described the beds in the valley of Otamita Stream west of East Peak from the Maoria problematica beds up to the top of the Carnic. and these are taken as the type Otamila Series. The same beds extend across the subdivision from Waiwera River, up Harris Stream, along the south side of Kaihiku Stream, leaving the subdivision at Glenomaru boundary, and continuing along the strike to the coast at the Nuggets The lowest Maoria problematica bed is a shell rock composed almost entirely of masses of the one shell. Above it is a soft bluish-grey mudstone with many scattered shells of Maoria. This soft bed forms a conspicuous depression between the hogbacks of the ranges. These beds occupy half a mile across the strike and, dipping steeply at 80° to 60°, are thus 2,500 ft. thick. The Maoria bed is everywhere steep, in places vertical, in places overturned and in contact with steep underlying beds. The actual contact was not seen, but the attitude suggests faulting. Among the fossils collected from beds classed in the Otamita Series Dr. Marwick has identified: Maoria problematica (Zitt) : Halobia zitteU var. zealandica Trech.: Hokonuia limwformis Trech. Trechmann classed these beds in the middle Carnic part of the Upper Trias. Warepa Series. —The Psfixtdomonolis bed crops out in Warepa Survey District, 70 chains north of west along the ridge from Rocky Dome and dins south at 60°. On the north side of the ridge is the soft-mudstone bed with Maoria and the upper part of it is a coarse sandstone that weathers out in large spheroids. This spheroidal sandstone and a conglomerate in places exposed below it, are taken as the base of the series. The beds from the base up to another strong conglomerate above the Pseudomonotis are grouped in the Warepa Series. They dip 60 . and extend a quarter of a mile across the strike, being therefore I,looft. thick. They stand steep in contact with steep underlying beds. In Waiwera Stream the underlying Maoria beds dip south at 80° and the basaj Warepa greywacke dips north at 70°, but no contact is exposed. Probably the beds are overturned at a fault. In other places there is no reversal of dip, the beds of the two formations being parallel. Trechmann classed the Pseudomonotis beds in the Noric part of the Upper Trias.

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