H.—34.

GEOLOGICAL SURVEY BRANCH. Ebpoet op Director (Dr. J. Henderson). During the year ended 31st May, 1936, official visits were paid by the Director to Tokatoka, Pahi, Te Aroha, Porangahau, and Wanganui in the North Island, and two visits to Reefton in the South Island. Mr. M. Ongley began the detailed examination of the Dannevirke Subdivision, and, working from Porangahau and Wanstead, has mapped three survey districts in whole or in part. Mr. M. Gage assisted in the early part of this work, and Mr. A. M. Quennell in the later. Before starting at Porangahau. Mr. Ongley mapped a small area near Blairlogie, east of Masterton, and traced the fault on 'which movement occurred in 1855 from Maurieeville to Makuri. Towards the end of the season he examined a deposit of calcareous sinter out from Hastings and reported on the prospects of underground water in an area near Dannevirke. Mr. Macpherson, who for some years has made detailed examinations of gold-bearing deposits, continued this work on the West Coast in conjunction with the geophysical party. Most of his work was in the Reefton district, but he also visited Hokitika, Kumara, Kotuku, and Ahaura. The important gold-bearing Reefton district was mapped more than twenty years ago, and geological knowledge and geophysical technique has now advanced sufficiently to render a resurvey advisable. Mr. Macpherson and Mr. Modriniak will continue this work next season. Mr. Healy, assisted for short periods by Mr. E. A. Cuttriss and Mr. R. W. Willet, continued the geological mapping of the Whakaea Subdivision begun last season by Mr. Macpherson. He worked chiefly from Waikaka and Wendon, and mapped in all some 250 square miles. He also reported on auriferous deposits near Port Molyneaux and Wetherstones and examined the low-level adit of the Bendigo Mine, near Cromwell. Dr. L. I. Grange some years ago examined the Rotorua-Taupo district, but was transferred to other work before he was able to complete his report. Last summer Dr. J. Marwick and Mr. H. E. Fyfe spent a few weeks in the district, and they will assist Dr. Grange in finishing his manuscript. Dr. Marwick and Mr. Fyfe also hurriedly covered the Te Kuiti district, which Dr. H. T. Ferrar mapped in detail some years ago. Mr. N. H. Taylor, who assisted the late Dr. Ferrar, has been transferred to the Soil Survey Division, and Mr. J. H. Williamson, who also assisted for a year, has left the Service. Dr. Marwick hopes to be able to prepare the bulletin describing this district. Before leaving for the field Dr. J. Marwick was able to complete, in collaboration with Dr. H. J. Finlay, a paleeontological memoir on " The Wangaloa and Associated Faunas of the Green Island : Kaitangata Subdivision." This important work, which occupied several years, is now in the hands of the printer. Mr. G. E. Harris made three large drawings and eleven blocks for photolithic reproduction, and prepared twenty-three field sheets for the field geologists. He also made nineteen tracings and coloured over a hundred prints for the geophysical parties, and did some miscellaneous work for other branches of the Department. The thirtieth annual report was published during the year, and several maps were printed for bulletins yet to be issued. Dr. Marwick contributed a paper entitled " Some New Genera of the Myalinidee and Pteriidse of New Zealand " to the Transactions of the Royal Society of New Zealand. At the Science Congress held during May, 1935, at .Dunedin, Mr. Ongley read papers on " The Taieri Mouth Breccia " and " The Old Man's Bluff Flow-slip," and Mr. Fyfe on " Sandstone Dykes at Hurunui Mouth." The Department of Scientific and Industrial Research issued a bulletin entitled "Water-supplies of Farms and Dairy Factories in Hamilton Basin and Hauraki Lowlands," by Mr. N. H. Taylor. An extensive correspondence on matters of geological interest has been dealt with, and many samples of rocks, minerals, and ores have been examined. The usual periodicals and exchanges have been received and placed in the library. DANNEVIRKE SUBDIVISION. (By M. Ongley.) Dannevirke Subdivision was examined by M. Ongley from 2nd January, 1936, to 3rd June, 1936, assisted from the beginning to 13th February by Mr. M. Gage, B.Sc, Assistant in Geology at Victoria University College, and from 16th March to the end by Mr. A. M. Quennell, B.Sc. The work was advanced by a visit from Dr. Henderson, Dr. Marwick, and Mr. Fyfe, who spent a day examining critical sections, and by several visits from Dr. Grange, Director of the Soil Survey Division, and his assistants Mr. Pohlen and Mr. A. M. Quennell, the latter of whom on 16th March was transferred to the Geological Survey. In the district Mr. E. L. Hunter, of Rangitoto, and Mr. L. Cowan, of Porangahau, kindly assisted the work. Three-quarters of Porangahau Survey District, half Motuotaraia, and the small Blackhead district have been examined and mapped, the area examined being 200 square miles. Steucture. Dannevirke Subdivision adjoins the north of Eketahuna Subdivision, of which the geological map was published in the annual report for 1935, and is geologically similar. As was shown in that map, the grain of the country trends east of north, and the folds and faults continue through Dannevirke Subdivision. The big Akitio syncline, eight miles wide, mapped and described in the 1935

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