Publications

Suban field in southern Sumatra, Indonesia, is a fractured carbonate/crystalline wet-gas reservoir located in a tectonically active island-arc setting. Reservoir-scale right-oblique reverse faults and folds that have trapped the hydrocarbons have been related previously to deformation in the back-arc setting of South Sumatra associated with oblique subduction of the Indo-Australian plate at the Sunda trench (Hennings et al., 2012). Increased well productivity in some parts of the field was inferred to correlate with completing wells in the damage zones of critically stressed faults. Satellite interferometry acquired over the three-year period between mid-2007 and early 2011 involving specially stacked and filtered interferograms, following prior applications to heavy-oil fields and Arctic sea ice by Soofi and Sandwell (2010), reveals active deformation within Suban field. Several areas of localized subsidence potentially exceeding ~5 mm/yr were identified in the field. Areas of uplift and horizontal movements of comparable magnitude were resolved across the approximate position of the inferred surface trace of the major right-oblique, critically-stressed fault zone in the southwestern part of the field, corroborating wellbore-based inferences and independent observations of active surface deformation. Block-tectonic models constrained by GPS measurements across the entire Sumatra contractional orogen predict comparable magnitudes and directions for horizontal motions observed locally at Suban. The combination of InSAR and GPS-based plate-tectonic models provides a robust tool for monitoring the deformation of oil and gas fields located in tectonically active areas.