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Geophysical work commenced at the beginning of September 1949, and was completed in December. Of this period, ten weeks were spent at Hermidale and five weeks at Girilambone. The operations comprised both geomagnetic and self-potential surveys. The geology, history, and the results of the work for the areas surveyed, are described in this report.

This collection of fossils from the Portland area consists chiefly from mollusca, but where a small portion of sediment was attached to the fossils, it was removed and washed down for micro-examination. The number given to each sample refers to the registered number in the Victorian Geological Survey Collection. The results of the examination are recorded in this report.

For the first time the hypostoma of an eodiscid trilobite, Pagetia bootes Walcott, is described. The presence of a doublure with terraced lines, and schizochroal eyes as observed on Australian Pagetiae, is mentioned. Obviously the trilobite nature of the Eodiscidae is no longer in question.

The writer received instructions to commence the geological mapping of the Port Moresby area with special attention to economic aspects, such as, raw materials for the manufacture of cement, materials for concrete aggregates, road surfacing materials, etc. This work was commenced on November, 30th, 1949, and a general rapid reconnaissance of the more readily accessible areas carried out.

At the request of the Minister for Works and Housing, a geological survey of the Canberra Brickyards was commenced in October 1949, to determine present reserves of brick making materials. This interim report contains a description of the strata and structures exposed in the brick pits, and details of estimates of shale reserves. A full geological report will be prepared when the extended survey is complete.

The Zeehan silver-lead-zinc field is in the West Coast Region of Tasmania. Following on the geophysical work carried out for Zeehan Explorations in 1947-1948, the Bureau was requested to carry out a survey on the Mariposa lease held by North Broken Hill Ltd. The purpose of the survey was to examine the Mariposa area for possible magnetic and gravity effects associated with the known mineralization and thence to determine the extent of this mineralization; and also to investigate the swamp covered limestone area for hidden mineralization. Further, it was considered that the results of the survey and behaviour of the instruments in the difficult terrain would serve as a guide to the usefulness of the magnetic and gravity methods in other similar prospecting areas in the Zeehan field. An account of the geophysical work and its results is given in this report.

The writer, accompanied by Mr. W.L. Hawthorne of the Geological Survey of Queensland, visited Longreach between 6th to 16th July, 1950, to inspect an area embracing Oakley, Cleeve and Kelso Stations, 8 to 14 miles north-east and east of Longreach. The purpose of the inspection was to re-examine the area previously mapped by Oil Search Ltd., and, if at all feasible, to recommend sites for deep drilling or scout drilling. In all an area of about 18 square miles was examined in sufficient detail to confirm Foster's mapping and to indicate that surface mapping could have little but negative value. The general geology of the area and previous investigations are described. An account is given of the present field investigation, and its results, together with recommendations for future work.

A visit of one month was paid by the writer to the North-West Basin and the Fitzroy area of the Desert Basin. It is largely due to the careful planning of the excursions by the Senior Geologists in charge that a coherent picture of the stratigraphical and tectonical conditions was obtained within the comparatively short time at disposal. This note contains a few remarks on the stratigraphy and tectonics of both areas in connection with oil prospects.

During the period 29th September to 2nd October 1950, the writer and geologist N. McKay, investigated the area near Wyndham, in which Mr. N. Orchard claims to have obtained a pitchblende sample in 1919. Following the examination of the area referred to by Mr. Orchard, an examination was made of a supposed radioactive deposit reported by Mr. E. Crocker of Wyndham. The observations made during these investigations are described in this report.