A geological reconnaissance of the Katherine-Darwin region, Northern Territory with notes on the mineral deposits

The Northern Australia Development Committee (a Committee composed of representatives of the Commonwealth and the States of Queensland and Western Australia) has recommended that a series of regional surveys be made in Northern Australia with the object of providing data which will enable development of the region to be planned on a scientific basis. These surveys are being made under the direction of the Commonwealth Scientific and Industrial Research Organization. From June to September 1946 the writer accompanied the C.S.I.R.O. party which was engaged in a reconnaissance survey of the Katherine-Darwin region. Christian, ecologist and leader of the party; Mr. G. A. Stewart, soil surveyor; and Mr. S. T. Blake, botanist. The area examined consists of 27,000 square miles in the north-western portion of the Northern Territory, west of longitude 133° east and between latitude 12° and 15° south. (See Plate 1 for locality map and reference to Australian map grid.) The primary object of the survey was to determine pastoral and agricultural possibilities. A geologist was attached to the party mainly because the area to be surveyed had been very incompletely mapped and the existing geological records did not provide an adequate background for the soil and pastoral work to be undertaken. The primary function of the geologist was, therefore, to provide this background for soil interpretation, but it was also intended that he should gather as much information as possible on the stratigraphy and mineral possibilities of the area. During the course of the investigation it was found, that geological mapping provided the essential framework into which much of the other scientific data could be fitted, and a fairly complete investigation of the stratigraphy and geomorphology of the area became essential. An account of the stratigraphy and geomorphology are submitted in this report with a reconnaissance geological map of the region. This geological map is the result of the combined work of the party and could not have been completed without the full co-operation of the other members and particularly of Mr. G. A. Stewart. An area of approximately 27,000 square miles had to be mapped by a series of traverses in a period of approximately four months, and the geology of the areas between these traverses had then to be filled in from available geological maps and records, and from aerial photographs which covered only parts of the region investigated. (See Plate 2.)