Long Term Operational Observation Of Ground Deformation In The San Joaquin Valley
Since 2001, we have produced ground deformation maps on a continuing basis over fields in Bakersfield, California. The examples provided in this paper will show ground deformation that reaches rates of 80 cm/year (31 inches/year) and extends to a maximum subsidence of 3.9 m (12.8 feet) in 12 years. This data may be useful in historical studies of injection and production methodologies and can be used as a boundary condition for geomechanical and reservoir modelling. The long term study of ground deformation from space provides interesting challenges — not the least of which is changing satellite systems. In recent years, a number of RADAR satellites have gone off line. A second generation has replaced them but we can anticipate that this generation will be defunct before the oil recovery activities in the San Joaquin Valley are finished. The methodology we present here shows a validation of the use of multiple satellites to monitor long periods of ground deformation. In order to demonstrate the use of satellite RADAR to operators, we also present a comparison study of GPS and InSAR movement estimates. A study to validate the measurement systems was undertaken with funding from the Pipeline Research Council International (PRCI) and shows excellent agreement between the two measurement systems. Finally, we demonstrate a methodology that combines multiple observations from multiple satellites to demonstrate both the accuracy of the technique and allows for fast time sampling of the ground — faster than is available by exploiting the satellites' natural revisit periods. That is by using multiple satellites and multiple imaging modes on those satellites, we can demonstrate observations as close as once every 3 days.
AAPG Datapages/Search and Discovery © 2014 Pacific Section AAPG, SPE and SEPM Joint Technical Conference, Bakersfield, California, April 27-30, 2014