Crown and Lasseter

Browse Basin


About the Exploration

Santos continues to progress appraisal studies and exploration of promising acreage in the Browse Basin. 

In 2012, Santos drilled the Crown-1 exploration well in WA-274-P in the Browse Basin, to test a large independent structure between the Poseidon and Ichthys fields, resulting in a significant gas discovery. The well was drilled to a total depth of 5,301 metres and intersected 61 metres of net gas pay in the Jurassic-aged Montara, Plover and Malita reservoirs between 4,873 and 4,998 metres. The well did not intersect a gas-water contact. Pressure data were acquired from multiple points indicating that gas would be expected to flow at a high rate and multiple condensate-bearing gas samples were recovered to surface. The preliminary contingent recoverable resource estimate range for the discovery is 0.5 tofive trillion cubic feet. In 2013, the integration of offset well data led Santos to upgrade its resource expectations for the discovery.

On 22 August 2014, Santos announced a significant gas-condensate discovery at the Lasseter-1 exploration well in WA-274-P. The well intersected a gross gas condensate bearing interval of 405 metres. Wireline logging to date has confirmed 78 metres of net pay over the Jurassic-aged Lower Vulcan and Plover intervals, between 4,880 and 5,285 metres MDRT (Measured depth rotary table).

This interpretation has been confirmed by pressure and sample data. The samples confirm excellent mobility in the higher porosity sands in the Lower Vulcan. Multiple independent hydrocarbon columns are interpreted, including an estimated 250-metre column for the Lower Vulcan reservoirs.

Multiple hydrocarbon samples have been recovered and the initial analysis confirms a condensate to gas ratio in the range of 10-25 bbls/mmscf and inerts consistent with proximal field gas compositions and pre-drill expectations.