The Abminga bedrock drilling program was initiated in 1999 as part of the Targeted Exploration Initiative of South Australia (TEISA) strategy conceived by the SA Government and implemented through PIRSA's Mineral Resources Group. Drilling was proposed for the easternmost Musgrave Block, and was to be performed on the Tieyon and Ayres Range South pastoral leases located immediately east of the Anangu Pitjantjatjara (AP) Lands — a region with very little known geological information about the underlying basement rock. Accordingly, the aim of the program was to investigate the nature of the basement below shallow cover, thereby producing a set of comprehensive, accurate and relevant geoscientific data for the easternmost Musgrave Block. The field part of this program commenced in May 1999 and was completed by August 2001, after having been delayed twice by rain. The campaign finally consisted of 140 reverse circulation drillholes totalling 5123 m, with all but a few drillholes intersecting fresh basement. The holes were drilled through cover to target basement lithologies corresponding to various aeromagnetic intensity signatures recorded on the Alcurra, Tieyon and Treloar 100k map sheets. The majority of the holes intersected Birksgate Complex, including numerous occurrences of Pitjantjatjara Supersuite granitoids. Olivine-dolerite dykes, some of which contained visible sulphides, were also encountered. Broad areas exhibiting a low magnetic signature, which had previously been interpreted as being underlain by possible ultramafic intrusions, were instead identified as arising from chloritic alteration zones formed in Birksgate and Pitjantjatjara Supersuite host lithologies. Various drillhole samples have subsequently been analysed for their geochemistry, petrology and groundwater chemistry.