During 1970/71, two large explosions set off at the Ord River Dam building site in Western Australia were recorded on 2000 km long land-based shot recording lines by the BMR and a number of university seismic research groups, and the results were used to interpret upper mantle structure down to depths of the order of 200 km (Denham et al., 1972; Simpson, 1973). These investigations were, at the time, the most extensive long range deep seismic soundings of their type made in Australia, and so shortly afterwards, when later in 1971 the BMR fortuitously received a gift of 360 t of explosives from West Australian Petroleum Pty Ltd (WAPET), a number of suggestions were made about how it could best be used in setting off a few large explosions within Australia to enable further recordings out to distances beyond 1000 km, and thereby add to knowledge of upper mantle structure below the continent. Also during 1971, the International Association of Seismology and Physics of the Earth's Interior (IASPEI) had received novel proposals to use 10 t marine shots to generate teleseismic waves which could be recorded out to angular distances of 90 degrees from the shot position (Jacob & Willmore, 1972). This sort of data is normally available only from earthquake sources, which have location and timing uncertainties, and from nuclear explosions, which are infrequent and have political aspects which seismologists prefer to avoid. So it was hoped that if using 10 t shots offshore in Australia could give comparable results, the method could be a relatively cheap way of obtaining controlled deep mantle information. The BMR therefore arranged to undertake such a trial in conjunction with the planned other large shots. The 1972 Trans-Australia Seismic Survey (TASS) evolved from the various circumstances and ideas mentioned above, and the positions of the recording traverses were determined by the chosen locations of the shots and their associated logistical problems. By then also, the BMR and a number of universities were developing unattended seismic tape recording systems for field use, and were better equipped to conduct such a survey than during the Ord River Dam explosions of 1970/71. On 25/10/1972, the BMR made two ~80 t underground explosions at Kunanalling in Western Australia and at Mount Fitton in South Australia, and subsequently, on 19/12/1972, a trial 10 t marine underwater shot was detonated near the sea bottom in Bass Strait, 70 km south of Orbost. Seismic P- and S-wave energy dispersed by these blasts was detected at distances of up to 2500 km away. This record describes the shot firing preparations and methods, and the scope of recording operations connected with TASS, and lists its recording locations and shot statistics; a table of seismic wave arrival data is also presented. The techniques used to fire the Bass Strait shot will be of particular interest because it was the first shot of its kind attempted in Australia. It is intended by BMR that interpretation of the results should be reported elsewhere.