Report on mine maintenance, costs, equipment, employment, reserves, and workings.

Sediments of Lower Cretaceous age are widely distributed in Queensland, northern New South Wales and northern South Australia. Their distribution is closely linked with the Great Artesian Basin, which covers an area exceeding 500,000 square miles. Many bores have been put down in this Basin to tap the aquifers which are present in the Jurassic rocks underlying the Cretaceous. Much material remains to be examined and a full report will be prepared after the examinations have been completed. This report comprises notes on the source of microfossil material, notes on the microfauna, a list of localities, and a distribution list of foraminifera. A map of the localities from which samples have been examined is included.

The stock saleyards comprise Block 41, Gungahlin district and are on the southeastern side of Federal Highway, 3.5 miles north from Civic Centre. A smaller area on the western extremity of the block, including stock pens, huts etc. is without water supply. The topography, geology and possibilities of obtaining underground water are discussed in this report.

Findings from a micro-examination of samples taken from the depths of 2,110 feet down to 3,533 feet 11 inches. The series is in continuation of that reported upon 11/10/44.

A preliminary geological examination of an area at the northern extremity of Gungahlin district was carried out for the purpose of determining with fair approximation the area occupied by slate apparently suitable for brick-making. The geology of the area and the suitability of the site for a brick pit are discussed in this report. A geological sketch map of the district is included.

The geophysical surveys reviewed in this report were part of an investigation carried out by the Commonwealth Government on behalf of the British Government. Deposits of uranium minerals occurring at several places in the Northern Flinders Ranges of South Australia, and centred about Mount Painter, were subjected to detailed geological examination followed by surface and underground prospecting by means of costeans, shafts, drives, etc. The geophysical work undertaken with the object of assisting the geological examination by measuring the radioactivity of rocks in situ and of hand specimens and assisting the prospecting work by making estimates of uranium content of mine samples. The geophysical surveys consisted of two main parts, namely, field surveys to locate and delineate areas of high radioactivity, and laboratory work to make approximate determinations of uranium content of mine samples by measuring the radiation from them. It is proposed to describe briefly the fundamental nature of radioactivity with specific reference to such features as have a particular bearing on the problems encountered in the field and assay work. In addition, it will be necessary to deal briefly with the geology of the various areas covered by the field work in so far as it effects the geophysical problems.

A report was prepared in December, 1944, on the ore reserve position at the Mount Bischoff Tin Mine. Since that date, further field work has been carried out, and the additional observations made have rendered necessary a revision of conclusions advanced in that report. The present report is to be read as a supplement to the previous one, but supercedes it in many respects. A revised summary of the ore reserve position is given herein. The additional geological observations affect both the interpretation of the structure of the Mount Bischoff ore-body as a whole, and the interpretation of the structure of individual ore occurrences.

Results of a micropalaeontological examination of samples from a depth of 50 feet down to 1000 feet.

Results of a micropalaeontological examination of samples from bores Nos. 3855 and 3859. Samples were from the depths of 7 to 427 feet down and 1 to 977 feet down respectively.

Results of an examination of samples from the depth of 1564 feet down to 2015 feet.