The stratigraphy and structure of an area in the Carnarvon sedimentary basin covered by the Williambury and Moogooree one mile sheets, is described. Resting unconformably on a Pre-Cambrian basement of schists gneisses and granites, are Devonian marine sediments 4750 feet thick, followed conformably by Carboniferous approximately 2150 feet thick; these are separated from the overlying Permian more than 8000 feet thick, by a possible hiatus. The Cretaceous System is represented by about 40 feet of siltstone lying unconformably on the Palaeozoic rocks. Marine Tertiary arenaceous deposits are widespread and have a maximum thickness of 80 feet; they are not seen in contact with the Cretaceous rocks. The whole area has been subjected, in Tertiary time, to lateritisation, the most prominent feature of which is the presence of a silicified cap ranging in thickness from a few feet to 30 feet. In one place a post-laterite deposit of 12 feet of probably fresh-water limestone has been observed. An account is given of the structural geology, geological history, and physiography of the region.

Superficial deposits of ferruginous manganese ore occur on the southern end of the Teano Range, Peak Hill Goldfield, Western Australia at about 150 miles by road north-north-west from Meekatharra. During the course of an investigation of new manganese discoveries in north-west Western Australia by L.E. de la Hunty of the Geological Survey of W.A. and the writer, the opportunity was taken to inspect two groups of small deposits in the Teano Range. One group contains about 14,200 tons of ore which averages about 2 per cent manganese and 32 per cent iron, and the other group 4,000 tons of marginal grade containing about 46 per cent manganese and 3.5 per cent iron. The former group is not of marketable quality and the other is too small and too remote to be of commercial value.

The Crater Prospect is situated about 4 miles south-south-east of White's workings and 1 mile north-east of the junction of Batchelor Road and the Darwin-Birdum railway line. It is the name assigned to a type area of an extensive radioactive bed of conglomerate. Low grade but wide-spread radioactivity was discovered by R.S. Matheson and D.F. Dyson (geophysicists) in June 1951, while prospecting along the sedimentary beds out-cropping immediately south of the Rum Jungle granite on the south-side of Giant's Reef fault, and on the south side of another major parallel fault. Geiger-Muller traverses along the strike of a grit-conglomerate horizon away from the Crater prospect revealed that the radioactivity extends westwards for 1.5 miles and for half a mile to the east. The radioactivity, which was confined to the conglomerate, was low-grade and discontinuous over this distance of 2 miles. The Crater Prospect, which can be regarded as a type locality, was geologically mapped by the writer on a scale of 200 feet to one inch after the area had been radiometrically contoured, and the plan accompanies this report (Plate 1). [The geology and structure of the prospect, nature of the radioactivity, and prospecting recommendations are discussed].

The Laurieton area was visited on 29th-30th January by N.H. Fisher and D.E. Gardner, with R. McLeod, field assistant. Boring and sampling were carried out of a beach deposit south of Grants Head where North Coast Minerals Ltd., are erecting a treatment plant. A brief examination was also made of the area south of Pt. Perpendicular, where exploratory boring was in progress. The deposit south of Grants Head is 2 miles north of the entrance to Camden Haven Inlet and about 4 miles by road from Laurieton. The area that was examined south of Pt. Perpendicular and Camden Head is 2 miles east of Laurieton.

The area investigated, of approximately 16 square miles, is 10 miles east of Singleton in the Parishes of Sedgefield and Marwood, County of Durham and in the Parish of Belford, County of Northumberland. The Bureau on Mineral Resources drilled 5 rotary cored bores, as shown on BMR Map N14/109, to 150 ft., 301 ft., 167 ft. 1 in., 202 ft. 8 in. and 131 ft. respectively. The result of drilling was total absence of coal. This may be seen in the attached logs.

An area of approximately 32 square miles in the vicinity of Rye Park has been mapped in greater detail than that of previous regional surveys. Three possible tungsten-bearing areas have been delineated as warranting magnetometric and plane-table surveys. An extension of each of these three areas is indicated. Attention is drawn to copper, tin, silver, lead, and zinc mineralisation of the area, and it is considered that there are possibilities of finding payable orebodies containing these metals.

Widespread use of radio-active tracer elements in medicine, and the increased interest in the search for radio-active minerals, have led to the development of a variety of instruments for the detection of ionising radiations, and their general use by scientists who may have had no training in physics or electronics. While these instruments present a great diversity in appearance, the functioning depends on general principles which apply to all such equipment. The aim of these notes is to present these general principles in a simple form. For details of design, which are often highly complex, and require great skill and experience, reference should be made to the works listed in the bibliography.

During 1951 three separate sets of La Cour pattern Quartz Horizontal Magnetometers were received from the Danish Meteorological Institute. These instruments which are only semi-absolute, were calibrated at the Rude Skov Magnetic Observatory against the standard adopted by that observatory. As the Australian observatories are based on the International Magnetic Standard housed at Cheltenham near Washington, U.S.A. (hereinafter referred to as I.M.S.) it was decided to compare them against the Toolangi magnetometer as soon as possible after their arrival in Australia. Moreover, as the stability of these instruments depends on the torsion properties of a quartz fibre and on the magnetic moment of a magnet, regular comparisons should be made with an absolute magnetometer and the results used to control drift that might occur. The comparisons made immediately after the arrival of the instruments in Australia would thus constitute a starting point in the future control of the Q.H.Ms. [An account is given of work done between 1951 and 1952. Results are appended.]

White's South prospect is situated on the southern bank of the Finniss River (East branch) about 400 feet south southwest of White's Deposit (Ward 1953). Rocks do not outcrop in the area, but low radioactive anomalies were located in this area by the Geophysical Section 1951 suggesting that the western continuation of White's Deposit after faulting might be beneath the soil cover. Low grade ore intersections were obtained in five diamond drill holes put down in the area in 1952. A plan of the area on a scale of 40 feet to 1 inch accompanies this report (Plate 1).

The air-borne scintillometer survey near Katherine during October, 1953, failed to cover a triangular area in the south-east corner of the Katherine sheet, as it was beyond the range of the Shoran beacons. The area is part of a Bureau of Mineral Resources reservation taken out to protect the ABC Prospect. Several trial flights were made over the area, however, in an attempt to detect the presence of any significant radiometric anomalies. During these flights, Geologist A.B. Clark acted as an observer to spot on photo-mosaics the positions at which anomalies might occur. A third order anomaly was recorded during a flight along Maude Creek at a point thought to be within 1 mile of the junction of Dorothy Creek and Maude Creek. A search was made later by D.E. Gardner with the object of finding the source of the anomaly and the results of this work are given below.