C.—6

1900. NEW ZEALAND.

REPORT ON THE PUPONGA AND PAKAWAU COALFIELDS, COLLINGWOOD COUNTY. BY ALEXANDER McKAY, ESQ., F.G.S., GOVERNMENT GEOLOGIST.

Presented to both Houses of the General Assembly by Command of His Excellency.

Wellington, 30th June, 1900. Sir, — I have the honour to acknowledge the receipt of instructions to visit and report on the coal-seams at Puponga, and I accordingly report as follows : — Narrative. In compliance with the above instructions I left Wellington on the 12th June, and Nelson for Collingwood on the 15th, and the following day Collingwood for Puponga, at which place I arrived and pitched camp on the I.6th of that month. I remained at Puponga till the 21st, during which period I examined all the known outcrops of coal in that part of the district, and on that date shifted camp to the valley of Taipata Creek, midway between Puponga and Pakawau Inlet. On the 22nd I removed to Pakawau, and the same day examined the Pakawau Coal-mine and the formations exposed on the south • side of the Pakawau Gorge, and the western slopes of the mountains farther to the south. On the fallowing day, 23rd June, I returned to Colliugwood, and the same day left for and arrived at Nelson about midnight. On the 25th I visited the chrome deposits Being worked on the south-west side of Croixelles Harßour By Messrs. Tatton and Jackson, and returned from Nelson to Wellington on the 28th June. The chrome deposits examined on the 25th June will Be reported on separately. Geology. The geology of the district Between West Wanganui Inlet and the lower Aorere Valley and Golden Bay to Puponga Point is concisely descrißed in a report on the geology of Collingwood County By James Park, P.G.S.,* the map illustrating which shows the Boundaries of the different groups of strata, approximately correct, over that part of the district dealt with in this report. * Geological Reports, 1888-89, pp. 186-243.

Mr. Park descrihes the sequence of the Cretaceotertiary rocks in descending order as Being,— "a. Grey Marl series. 1. Blue and yellow clays. 2. Marly greensands, passing into shelly limestone. " b. Ototara series. 1. Compact shelly limestone. 2. Quartz sands, grits, and ferruginous cements, passing into haematite. "c. Greensand series. 1. Ferruginous sandstones, with seams of Brown coal. 2. Conglomerates, with seams of Bituminous coal.-" Of the lower Beds (c, 2) Mr. Park says : " Between Puponga Inlet and Cape Farewell the con- , glomerates are very largely developed ; But the seams of coal they contain always appear to Be too small to work. The long lines of fine escarpment sections at this place afford the most valuaßle and reliaßle evidence as to the relation of the Bituminous-coal measures to the Brown-coal measures. The sequence usually reads, — "1. Marly greensands, passing [upwards] into limestone. "2. Grey sandstone and grits. "3. Coarse ferruginous sandstones. "4. Coarse conglomerates and peßßly sandstones. "5. Ferruginous sandstones and shales with thin seams of Bituminous coal. "6. Coarse, heavy conglomerates." " In the West Wanganui district the Brown coals occur aßout the Base of the coarse ferruginous sandstones [Beds 3 of the ahove sequence] ; But they are ahsent in this line of section, their place Being apparently occupied By the conglomerates (No. 4), which rapidly thin out as they are followed to the westward." (Geological Reports, 1888-89, pp. 237-238.)