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The rocks showing along.the banks of Coal Creek belong to the coal-bearing series, and the section reads much the same as that of Koiterangi, with the exception that the lower breccia conglomerates are absent, or have but a feeble development. The lower beds exposed are gritty sands, sometimes greenish from the presence of glauconite grains. Above these are grey grit sandstone, followed by dark shales, with which are associated thin seams of coal. Limestone similar to that of Koiterangi closes the sequence. The whole is arranged as an anticline, the axis of which is deeply cut into by Coal Creek. The total area ot these rocks is less than two square miles. The occurrence of coal-bearing rooks at Ross is interesting as forming part oi a line ot such rocks that lie along the base of the higher mountains from Kanieri Lake through Koiterangi and by way of Constitution Hill to Ross and the Mikonui River. Another patch of the same rocks is said to occur on or flanking Mount Fraser, towards the source of the Totara River ; but this was not visited. Albx * McKay * 11th December, 1900.

REPORT ON INDICATIONS OF PETROLEUM AT DEEP CREEK, LAKE BRUNNER, NELSON. By Alexander McKay, F.G.S., Government Geologist. In accordance with instructions, I went to Kotuku, Lake Brunner, for the purpose of examining the evidences of petroleum, reported as occurring in the valley of Deep Creek, near that P a ° Indications of oil are to be met with over a distance of half a mile along the banks of Deep Creek, and samples of rock—a soft sandstone—obtained by Mr. Molloy from two miles to the eastward also gave indications of the presence of oil. _ • , The first place visited, and where the strongest indications were met with, lies 60 chains north of Kotuku Railway-station and about 40 chains west of Molloy's homestead. At this place the oil rises to the surface on the left bank of a western tributary of Deep Creek, between which and the larger stream is a low alluvial flat. On the right bank of this lesser stream rise high terraces formed of gravels of older date, which, it may be, are the source of the oil at this place. Oil rises from the bed of the stream and passes away with the current. A wing-dam, enclosing a narrow strip of the creek-bed, 12 ft. in length and about 2 ft. in width, impounds the oil oozing from the low bank and bed of the stream ; and the water thus hemmed in was at the time of my visit covered to a depth of fin. with a brownish rather fluid petroleum, but oil was escaping through the dam and passing away with the waters of the creek ~,„"., Several small holes 1 ft. in diameter and scarcely more in depth had been dug m the alluvial soil at distances 12 ft. to 20 ft. from the bank of the creek, and these invariably showed the presence of oil though not to a greater depth than over the larger area hemmed in by the wing-dam. At this place there was no evidence as to what the primary source of the oil might be, and no attempt has been made to ascertain the nature of the rock underlying the gravels of the creek-bed. About a quarter of a mile further up stream oil was again seen oozing from the bed of the creek at a point where this was bounded by an alluvial bank about 4 ft. in height. At this place no attempt had been made to sink holes or collect oil. A quarter of a mile yet further up stream, or half a mile above the locality first described, oil again appeared on the waters of the creek, and could be obtained from a solidified gravel showing on the left bank of the creek. This locality is known as the Sawpit. The solidified gravels closely resembled those of the " Old-man bottom " as seen on the south-east side of the Grey Valley, in the broken hilly country between Nelson Creek and Orwell Creek or Mount Napoleon. Resting on this, 10 ft. or 12 ft. above the creek, is a mass of sandstone, which at first sight appeared to be an erratic boulder, but on closer examination proved to be in situ, and to the north-west at the Sawpit was seen to break up into two or more beds, interstratified with gravel-beds and soft sandstone. The coarser gravels underlying, on being broken into, showed the presence of oil, but, as oil floated on the surface of the pool in the creek, it was possible that the gravels had acquired the oil from that source when the creek was higher than at the time of my visit. The prospector who accompanied me as guide had no means, other than an old shovel, for digging a hole m these gravels and with this instrument the surface could be penetrated a few inches only ; yet as deep as could be reached oil appeared, and slowly oozed out of these gravels ; and I concluded that the gravels yielded oil, and had not received it from the surface of the pool as above indicated. I was informed that oil could be detected at places yet further up the creek, but the state of the weather did not favour penetrating a thick bush in search of indications no better than had already been examined. ~-,.. t -i * a • North-east of Mr. Molloy's homestead, and about two miles distant, traces of oil are found m a bluish-grey soft sandstone, and samples of this were brought to me, but I did not visit the locality. , , Geology of the District. The formations present in the district are : — (1.) Recent.— Gravels of the Arnold River and its various tributaries covering the low grounds and forming terrace of moderate height. . (2.) Older Pliocene.—" Old-man bottom." Coarse gravels, often subangular, and passing upwards into coarse breccia conglomerates.