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.)

Legacy product - no abstract available

The possibilities of finding evaporite deposits in Western Australia were investigated by C.L. Knight and E.K. Sturmfels on a reconnaissance trip from 12th September until 14th October, 1949. The localities in which primary gypsum beds or other indications of evaporites at depth were found or from which they are reported, are classified on the following pages according to the geological formations, and their position is shown on two accompanying maps.

This report describes the results of a micropalaeontological examination of three rock samples from the Poole Range area.

This report provides an overview of copper mining production in the Northern Territory between 1885 and 1947. Production, distribution, and economic considerations are generally discussed, and the principle copper producing mines are described in some detail. This description includes details of the geology and working of the lodes, ore grade, and recorded production figures.

The Nerrima dome is situated in an area of gentle folding 90 miles south-east of Derby in the Kimberley Division of Western Australia. The topography is essentially flat with local ridges formed over the more resistant sandstone beds of the Liveringa Formation. Outcropping formations are Permian and include the lower part of the Liveringa and the top part of the Noonkanbah Formations. The Liveringa Formation consists mainly of sandstones and grits and forms ridges which practically surround the structure; the Noonkanbah is mainly clays and limestones which have been reduced to flat plains with low outcrops of limestone and calcareous sandstone. Vertical closure of the structure is about 250 feet over an area of 30 square miles. The cores of Nerrima No. 1 Bore have been examined and at the present depth of 4271 feet the bore appears to be still in Permian rocks although no reliable interpretation of the subsurface geology at Nerrima can be made without further detailed information from areas to the north.

During the last three years much work has been done on laterites in Northern Australia by geologists of the Bureau and in particular those attached to the North Australian Regional Survey. The co-operation of soils officers and geologists in this survey has led to a better understanding of the significance of laterites and of the zones within the profiles. Since several parties from the Bureau are now working in Northern Australia it seemed opportune to discuss the nomenclature of laterites and to suggest terms and definitions so that laterites can be described and mapped in the same way by the several field parties. With this object in view geologists from the Bureau and officers from the North Australian Regional Survey discussed the matter and the following terminology and definitions are circulated now for criticism within the Bureau.

Note on plan No. G.26-2, which shows the results of Equipotential Line surveys conducted on the Comstock Area, during the years 1937 and 1938. It is supplementary to Plan No. G.26-1 which shows the results of similar surveys on the southern part of the Mt. Lyell area. Plan No. G.26-2 should be studied together with this plan and the accompanying report dated 13th May, 1948.

One gram of sample No. 1 and 2 grams of No. 2 were dissolved in about 100mL of hot water. After dissolving the soluble portions the solutions were filtered and the undissolved portions dissolved and weighed. This weight subtracted from the original weight of the sample gave the amount of soluble salts. The filtrate was diluted to 250 mls with distilled water, 100 mls being used for Ca and Mg determination. The results of this experiment are given in the report.

On 29th September, 1948, the writer, assisted by K.R. Fleischman, spent one day examining the rocks of the Cotter River Valley in the neighbourhood of the dam and mapping geological features which would have a bearing on the proposed extensions. Representative rocks were collected from the quarries on the right bank of the River below the dam. The mapping was done by chain, compass and Abney level. Aspects of general geology and engineering geology are discussed in this report. Two accompanying geological plans are included.