Standard curves for interpretation of the magnetic anomalies due to spheres have been derived. The anomalies in the vertical component, and the horizontal component in the direction of the traverse, are each found to be represented by a single family of curves. The horizontal component is found to be not represented by a single family, and separate curves for each field inclination and traverse azimuth are presented. Curves for the anomaly in the total intensity were not computed.

The Australian Calibration Line (ACL) , with a total gravity interval of 3 Gal, was established during 1970 between Laiagam in Papua New Guinea and Hobart in Tasmania. During 1973 the Australian Bureau of Mineral Resources and the USSR Geodesy and Cartography Survey made joint observations along the full length of the ACL. Measurements made with eight Soviet GAG-2 gravity meters established a gravity scale for Australia to an accuracy of 2.5 parts in 105. This scale and a datum of 979 671.86 mGal for Sydney A were adopted for Australia in 1973. The Soviet scale established for the ACL appears to be within 1 part in 104 of both the IGSN71 scale established for the Western Pacific Calibration Line by absolute determinations, pendulum measurements and international gravity meter comparisons, and the scale established for the Soviet Calibration Line by OVM pendulums. The Soviet scale for the ACL defines a milligal which is 1.5 parts in 104 larger than that defined by IGSN71 values for the ACL, and 5 parts in 104 larger than the 1965 Mean Australian Milligal that was used as an Australian milligal standard between 1965 and 1973. Both of these scales are partly based on Cambridge pendulum measurements made in Australia during 1950-51. These measurements are now thought to have been incorrect in scale. LaCoste, Romberg gravity meters have been used during six surveys along the whole or part of the ACL. The LaCoste observations have been reduced using the Soviet ACL scale and the new datum for Sydney A. The most probable values for airport gravity stations, calculated from the LaCoste results, have a precision of better than 0.01 mGal and are consistent to within experimental error with values calculated from the GAG-2 results. LaCoste observations reduced using the Soviet ACL scale give more accurate values for the gravity differences of the main intra-city ties and calibration ranges along the ACL.

This report presents the results of geochemical investigations in the Mount Isa district, northwest Queensland. Samples, mainly from cores, represent Group 2 Shales (comprising Kennedy Siltstone and Spear Siltstone), Urquhart Shale, Native Bee Siltstone, greenstones, and local basic igneous rocks. These have been used to study element distributions in mineralized and unmineralized localities. It was found that primary element dispersions are associated with the 1100 Cu orebody, but not with the Ag-Pb-Zn bodies. This, together with the different modes of occurrence of the orebodies, suggests that the mineralization at Mount Isa took place in two separate events. The Ag-Pb-Zn deposits are considered to be syngenetic whereas the Cu deposits appear to be, in part at least, epigenetic. The chemical evidence suggests strongly that much of the Cu in the silica dolomite bodies was derived from the underlying greenstones. In addition, an attempt has been made to differentiate the Urquhart Shale from the other units on the basis of chemical composition. Of the elements analysed, Ca appears to be the most diagnostic and it may be possible to define the upper limit of the Urquhart Shale using this element.

A collection of palaeontological papers 1972 (bulletin 150)

In January 1970, after a two-year period of inactivity, Ulawun volcano, on the north coast of New Britain, erupted. Ulawun is a stratovolcano built of basaltic and low-silica andesite lava flows and pyroclastic rocks, most of which were erupted from a central vent; many of the lavas were partly fragmented during flow, and some unsorted elastics mav have been deposited by nuees ardentes.

This Bulletin describes the geology of the igneous and metamorphic rocks of the Lamboo Complex in the eastern part of the Kimberley Division of Western Australia (Fig. 1). The area encompasses the western halves of the Lissadell, Dixon Range, and Gordon Downs 1:250,000 Sheet areas, the eastern half of the Mount Ramsay Sheet area, and the southeastern corner of the Lansdowne Sheet area. It is bounded on the east by longitude 128°30'E and 129°E (on the Lissadell Sheet), on the west by longitude 127°30'E and 126°45'E (on the Mount Ramsay Sheet), and by latitude 16°00'S and 19°00'S. The mapping of the Lamboo Complex is part of a current investigation of the Kimberley Division by the Geological Survey of Western Australia and the Bureau of Mineral Resources.

This Bulletin presents the results of systematic geological mapping in north Queensland by joint field parties of the Bureau of Mineral Resources and the Geological Survey of Queensland, during the period 1958 to 1963. The area investigated is more than 36,000 square miles, and extends from Princess Charlotte Bay in the north to the township of Ingham in the south, and from 142°30'E. to the shores of the South Pacific Ocean. It is the site of a Palaeozoic geosyncline the Hodgkinson Basin and includes part of the western Precambrian borderland, which is separated from the geosyncline by the Palmerville Fault, a large fundamental structure.

The Bonaparte Gulf Basin is a north-pitching syncline of Phanerozoic sediments, which are bounded to the south by Precambrian rocks and extend northward beneath the Timor Sea (Fig. 1). The landward part of the basin has been fragmented by faults, uplift, and erosion into a main outcrop area and three outliers. The eastern edge of the original depositional basin corresponds approximately with the present eastern margin, but the original extent to the south and west is unknown. Within the main outcrop is a Precambrian inlier, the Pincombe Inlier, which influenced deposition during the Upper Devonian and Lower Carboniferous. The main outcrop (Fig. 2) comprises Lower Cambrian volcanics, and Cambrian, Lower Ordovician, Upper Devonian, Carboniferous, Permian, Lower Triassic, and Lower Cretaceous sediments. The outliers contain only the lower part of this sequence, up to and including the lower part of the Upper Devonian.

This Atlas of isoseismal maps of Australian earthquakes contains the results of the ground intensity effects from all known Australian earthquakes for which adequate documentation is available. A total of 83 isoseismal maps are presented for 70 Australian earthquakes. The Atlas is arranged with each isoseismal map presented in chronological order, facing a page containing a brief description of the earthquake and the methods used to obtain the intensity data. References to the source of the map and to other publications that contain information on the earthquake's intensity are also given. The earliest map is from the July 1883 Mount Barker (SA) earthquake and the most recent from the November 1981 Suggan Buggan (NSW) earthquake. The largest recorded earthquakes from the Australian continent have occurred in Western Australia. These were the 1941 Meeberrie and 1968 Meckering events, which have magnitudes of about ML 7, and were felt at distances of about 900 and 800 kilometres from their respective epicentres. In South Australia, the 1897 Beachport earthquake (magnitude 6.5) produced the greatest shaking and was felt about 600 kilometres from the epicentre; in eastern Australia, the 1935 Gayndah (Qld), 1961 Robertson-Bowral (NSW), and 1973 Picton (NSW) earthquakes were felt out to about 400 kilometres and the 1918 Bundaberg (Qld) earthquake was felt at distances of about 650 km. The 1968 Meckering and June 1979 Cadoux earthquakes produced the highest observed ground shaking. Intensities of MM IX were experienced, and fault scarps, with throws of about a metre, extended over several kilometres for each earthquake. Intensities of MM VIII were recorded for the 1897 Beachport, 1902 Warooka, 1941 Meeberrie, 1949 Dalton-Gunning, and 1954 Adelaide earthquakes. Total damage caused by the June 1979 Cadoux earthquake was 3.8 million dollars (1979 prices) and the 1968 Meckering earthquake, 2.2 million dollars (1968 prices). The 1954 Adelaide earthquake caused 4 million pounds damage at 1954 prices.

Many of Australia's birds are unique to this continent, but none are more impressive than a group of giant ground birds, the Dromornithidae, one member of which may have exceeded in volume and weight any bird that has ever trod the surface of the earth. Although first discovered in the early 19th century, only two genera (Genyornis and Dromornis), both monotypic, had been recognized when work beginning in the 1950's in central Australia brought to light at least six new forms including three new genera (Barawertornis, Bullockornis, and Ilbandornis), described for the first time in this paper. Based almost entirely on post-cranial material, the Dromornithidae appear to be most closely related to the Casuariidae, the only other Australian ratite group, but before a satisfactory higher taxonomic allocation can be made, good cranial material is needed. Unfortunately, the maximum age of known dromornithid fossils is about 15-20 million years, and from that first record to the last in the late Pleistocene, only minor evolutionary changes are known to have occurred, namely: reduction of the forelimb, reduction of the medial digit of the foot, and development of hoof-like ungual phalanges on the foot. A much more fascinating evolutionary picture of this diverse group awaits future palaeontological discoveries.