This geological report on the Jervis Bay firebrick clay deposit and the Jervis Bay aerodrome is comprised in three distinct sections. The first discusses the situation and production history of the area, and describes the geological surveys completed to date. The second describes the geology and topography of the aerodrome. The final section describes the investigation of the firebrick clay and the results of this investigation, with reference to the aerodrome and the proposal for a new runway. Accompanying plans of the clay deposit and the aerodrome are included.

For nearly nine months of the year the river proper is confined to a narrow channel two to three hundred feet wide. During the remainder of the year, however, the river is subject to periodical floodings resulting from heavy tropical rain on its water-shed and for periods of a week of more at a time the low level bridge is covered by flood water. The dislocation of rail traffic which results from these periodical floodings has been a matter of serious concern to the Queensland authorities for many years and a decision was made to construct a high level rail and road bridge to replace the existing structure. Construction was commenced, but before it proceeded far, it was considered desirable that the depth of the bedrock, previously examined, should be established without doubt. In view of the uncertainty of the depth to be drilled and the very considerable difficulty in drilling through alternating layers of drift sand and boulder wash, a request was made by the Co-ordinator General of Public works for Queensland for a geophysical investigation of the site. A survey was carried out by the geophysical section of the Commonwealth Bureau of Mineral Resources during August and September, 1947. The investigation of the results is far from complete but the seismic method gave such concise results that this preliminary statement is justified. Geology, geophysical methods, results, interpretation, and testing are discussed in this report.

An examination was made of a proposed dam site at Geehi in April, 1947. The report comprises notes on access, general geology, evidence gathered from aerial photography, and the suitability of the site. Three accompanying plans, and a petrographic report on rocks collected from the vicinity, are appended to this report.

It was requested that the Branch examine the Naronga site with a view to determining whether it was suitable from a geological point of view for the construction of a flood control dam. The area was visited and mapped in March, 1946. The topography, geology, possible site and capacity of a retaining wall are discussed in this report. Three plates showing the area and sections accompany this report.

The principal alternative sites for an administrative centre which have been considered or suggested are discussed from the points of view with which a geologist and vulcanologist is primarily concerned - namely vulnerability to volcanic action, earthquakes, and tidal waves, foundations, water supply and accessibility of material suitable for road resurfacing, aggregate, etc. The areas considered are Rabaul, Nonga-Tavui, Keravat-Kabaira, Vunakanau-Taliligap, and Koko-Rapopo.

In response to the proposal for a new administrative building to be erected, 1/4 mile east of Parliament House, nine test pits were put down by the Department of the Interior for the purpose of examining the sub-surface conditions. Four of the pits were used for engineering tests of the bearing power of the rock foundations. The geology of the site is discussed in this report.

An investigation into the possibility of providing additional water supplies to the township of Tennant Creek was carried out by the Department of Works and Housing. A request was made to the Bureau in March, 1947, to carry out a geological examination of possible dam sites in the Tennant Creek area. A preliminary inspection of two possible sites was made on 5th June, and a detailed plane table survey of both sites was carried out on 6th and 7th July, 1947. The location, access, topography, general geology, engineering geology, and recommendations for future investigation and work are discussed in this report.

Following a request from the Department of Works and Housing, the Bureau of Mineral Resources carried out a geological investigation of a possible dam site in the valley of Pierce's Creek, a tributary of the Cotter River. The general geology of the area, and aspects of engineering geology, are discussed in this report. A geological plan of the site is included.

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.

The Commonwealth Flax Production Committee conducts a flax mill at Ballarat. The flax is first treated with water and 25,000 gallons per day are used in the process. After the treatment, the water is allowed to run to waste, and is at present being conducted through an earthen drain to natural drainage channels. This disposal of effluent water is not approved by the Ballarat Council, and other means of disposal have to be found. The objective of the present investigation was to determine if another borehole could be suitably sited to dispose of the effluent. The geology of the area, possibilities of disposal, and recommendations are discussed in this report. Two accompanying plates are included.