Role of Geology in Improving Secondary Recovery Operations in Richfield Oil Field, Los Angeles Basin

Marvin M. Katz

Detailed geologic reviews of older producing fields can often improve secondary recovery operations and identify additional reserves. A recent geologic review of the Richfield East Dome unit within the Richfield oil field (discovered in 1919) was conducted for this purpose. The structural setting of the Richfield oil field consists of two en echelon folds that are separated by a productive saddle. The Richfield East Dome unit overlies the southeastern fold within this field. The hydrocarbon-producing reservoirs for the Richfield East Dome unit are the Chapman and underlying Kraemer zones (upper Miocene Puente Formation), which consist predominantly of arkosic sands. Waterflooding began in 1974 for the Chapman and Kraemer zones. Currently there are plans to expand the Krae er waterflood. Oil accumulations are complexly controlled by stratigraphy and structure. Detailed log correlations, paleobathymetry, the paleogeographic setting, and the geometry of the producing zones indicate that these producing zones consist of an amalgamation of prograding sand-rich turbidite lobes with a south or southeasterly source. Detailed subsurface mapping of these turbidite lobes and detailed delineation of the faults in this area show the existence of a previously unidentified fault block and help redefine the productive limits of the producing zones.

AAPG Search and Discovery Article #91038©1987 AAPG Annual Convention, Los Angeles, California, June 7-10, 1987.