PEL 24 covering an area of 21,778 square km straddling the southern margins of the Arckaringa and Officer Basins, 100 km south of Coober Pedy, was granted to CRA Exploration Pty Ltd for five years from 30/11/83. That company, in its first foray into onshore Australian oil exploration for many years, planned to investigate the petroleum potential of three largely unknown pericratonic tectonic and thick depositional features termed the Tallaringa, Wallira and Phillipson Troughs. To this end it committed to spend a minimum of $6.4 million over the licence period on works including substantial new seismic acquisition plus the drilling of four exploratory wells. Activities carried out by the licensee during its four year term of tenure included: - compilation and assessment of previous company and government exploration data for the region; - the conduct in October-November 1984 of an environmental survey of PEL 24 to identify previously undescribed flora and fauna present there which would require protection from likely impacts of any proposed works; - the conduct as required from August 1984 through March 1986 of anthropological scouting surveys to locate and verify potential sites of Aboriginal significance, and to devise strategies for avoiding or protecting these from interference; - acquisition and evaluation of 170 square km of experimental reconnaisance airborne geochemical survey data performed in July 1984 by contractor Recon Systems Pty Ltd; - acquisition, processing and interpretation of 84.5 line km of reconnaisance experimental Vibroseis profiles along three lines in the central-eastern part of the licence (the 1985 Coober Pedy Seismic Survey) in January-February 1985 using contractor Seiscom-Delta United Pty Ltd; - acquisition of 114 line km of detailed ground magnetic and gravity profiles along four former seismic lines in December 1985-January 1986 using contractor Solo Geophysics and Co.; - acquisition, processing and interpretation of 315.9 line km of regional and semi-detailed Vibroseis reflection profiling along 10 lines spread across the licence area (the 1986 Ingomar Seismic Survey) in May-June 1986 using contractors Geo Systems Pty Ltd and Western Geophysical Co.; - reprocessing of 102 line km of 1970-71 SADM single fold dynamite reflection seismic data in August 1986 by Western Geophysical Co. in Singapore; - acquisition of 130 line km of semi-regional gravity data along five lines over the boundary between the Wallira and Phillipson Troughs in November 1986, again using Solo Geophysics; - drilling of the Arkeeta 1 wildcat/stratigraphic well to 1345 metres total depth in the central Phillipson Trough during December 1986, to sample and evaluate the inferred thickest Permian section within PEL 24.