Publication Name: The Sedimentary Basins of WA
Authors: M. R. King
Publication Volume: 2
Date Published: December 1998
Number of Pages: 31
Reference Type: Book Section
Abstract:
Looma 1 was drilled as an exploration well targeting the Ordovician Nita Formation and Acacia Sandstone in EP 353 of the south Canning Basin. The main predrill risks and uncertainties were identified as structural validity, reservoir quality and charge from an unproven kitchen. The well a tested broad, low relief anticline with structural closure at three different levels, all of which were found to be hydrocarbon-bearing. The primary objectives, the Nita Formation and the Acacia Sandstone both contained oil, and the secondary objective Nambeet Formation is interpreted to be gas-bearing.Both the Nita Formation and Acacia Sandstone were fully cored. Substantial mud gas readings up to Cs were recorded whilst coring and oil was observed bleeding from core from both objectives. Routine and special core analysis confirm the presence of live oil saturations. Testing recovered only oil-cut/water from both objectives and gas to surface from the Acacia Sandstone. Core analyses corroborated the DST test results, indicating poor reservoir quality for both the Nita Formation and Acacia Sandstone.
Looma 1 provides the first unequivocal evidence of mature, migrated oils from a South Canning Basin kitchen, proving oil charge to both the Nita Formation and Acacia Sandstone reservoir objectives. Depositional and diagenetic models indicate potential for better reservoir development east of Looma 1.