The Palaeozoic rocks of the Bonaparte Basin outcrop at the head and along the western side of Joseph Bonaparte Gulf and extend across the border between Western Australia and the Northern Territory. The Bonaparte Basin is the least known Palaeozoic basin in Australia, due partly to the remoteness of the area and the discouraging results of early coal explorations, and partly to the fact that the stratigraphical extent of the Palaeozoic sequence was only discovered in the last ten years. The Palaeozoic sequence so far established includes Cambrian, Ordovician, Devonian, Carboniferous and Permian sediments which rest on a pre-Cambrian basement and which are overlain in places by a mantle of Lower Cretaceous sediments. The authors intend in this paper to give an account of Carboniferous and Permian sediments of the Basin, as far as present knowledge permits, with briefer mention of the Lower Palaeozoic and Mesozoic sediments of the area.

This map has been prepared to display the probable form of the Isogonic Lines in the regions surrounding Australia, the boundaries being the meridians 85°E and 180°, and the parallels of latitude 10°N and 60°S. This report contains explanatory notes to the isogonic map.

A geophysical survey was made in the Rum Jungle district in October and November, 1950, using self-potential and potential-ratio methods. This investigation formed part of a larger programme of geological and geophysical exploration for uranium minerals. Self-potential surveys were made over three areas, namely, Brown's Copper Mine Area, Intermediate Area, and White's Area. A potential-ratio survey was made over only the first of these. This report gives an account of the geophysical work conducted in each of these areas. The results of the survey are described, and recommendations for future drilling work are given, for each of the surveyed areas respectively.

The material described in this report was collected and forwarded for examination by Mr. M.R. Banks of the Geology Department, University of Tasmania. The report comprises notes on the lithology, fossil content, state of preservation, and correlation, of the samples.

This report is comprised of nine separate sub-reports, referred to as records nos. 1951/3a to 1951/3i. Micropalaeontological examinations were conducted on samples from various localities in the region of Mt. Gambier, South Australia. The results of these examinations, together with any accompanying notes, are recorded in the respective reports.

For the purpose of obtaining further information as to favourable structural features in relation to brown coal seams within the Yallourn-Morwell-Traralgon area, a gravity survey is being carried out by the Bureau of Mineral Resources, Geology and Geophysics at the request of the State Electricity Commission of Victoria. In the following a preliminary interpretation is given of the results obtained by this survey to date. This interpretation includes a detailed correlation of the gravitational disturbances with the geological structures so far known. Practical experience to be gathered from the work so far done has been outlined.

The Government of India invited the Australian Government to send a representative to the celebration of the Centenary of the Geological Survey of India during January 1951. The first meeting of the Pan-Indian Ocean Science Congress was scheduled for the first week in January, 1951 so the Bureau of Mineral Resources, Geology and Geophysics selected M.A. Condon to attend the Science Congress and the Centenary Celebrations because his work in the North-West Basin of Western Australia would be of some interest to geologists working around the Indian Ocean. This report comprises a detailed itinerary and geological notes on the areas visited during the course of the visit.

The present report summarises the progress in the study of Cambrian fossils from the Northern Territory and north-west Queensland. The material being studied consists of large collections made in the Barkly Tableland by members of the Bureau of Mineral Resources, and a selected set of fossils borrowed from the Australian Museum. In addition, a comparatively complete collection from the Ord River and Mt. Panton is available for comparison. This report provides an overview of the work being carried out. Brief summaries are provided of the present state of research done by A.A. Opik, and of papers planned by other authors.

Three samples of limestone were collected during a geological survey of the Rigo area. One sample is of Upper Cretaceous age and the others of Lower Middle Miocene age. The samples were submitted for micropalaeontological examination. The results of this examination are described here.

The Desert Basin covers an area of approximately 140,000 square miles in the Kimberley and Eastern Divisions of Western Australia. Geological investigations have been almost entirely confined to the northern part of the area; the southern part is covered by parallel sand-dunes with a few scattered outcrops and is relatively unexplored. A programme of geological mapping was initiated in the area by the Commonwealth Government in 1948. The entire area is being mapped, using aerial photographs, stratigraphic studies are made and fossils are collected for correlation purposes. The aim of the investigation is the evaluation of the petroleum prospects of the area. During the period 1948 to 1950, mapping has been carried out in Dampier Land and the area north of the Mt. Fenton Fault. The information in this paper will refer mainly to the area already mapped with brief reference to the unexplored area to the south.