Successful Mature Field Re-Development At Mount Poso Oil Field, Kern County, California
The Mount Poso Oil Field was discovered in 1926 and has produced over 300 mmbo from a three way closure against an east dipping normal fault situated along the eastern flank of the San Joaquin Valley in Kern County, California. The field was on decline in January, 2012, producing 800 bopd from 300 wells in the Miocene Pyramid Hills formation. A combination of sixty new horizontal wells, a waterflood project, and re-development of the Oligocene Vedder formation have since increased production to over 3,000 bopd. Production is expected to increase further with a full field expansion of the waterflood and continued re-development of the lower Vedder formation. The Vedder formation was under primary production from its discovery in 1926, then steam flooded from 1973-1998 with a focus on the Upper Vedder, and finally shut-in from 1998-2012. The shallower clay-rich Pyramid Hills formation was largely bypassed until the mid 1980's, followed by workover appraisal, and then became the focus of development with vertical new drills in 1999 with the first laterals in 2005. From 2005-2012 the average well rates decreased from 4 to 2.5 bopd. In 2012 a successful horizontal well program built off the lessons learned from earlier development increasing production to 2,000 bopd by the end of the year with many 50-125 bopd IP wells. A successful Pyramid Hills waterflood was implemented by incorporating an updated geomodel, testing fluid compatibility with swelling clays, and utilizing the large inventory of existing wellbores to minimize costs. Reappraisal of the previously abandoned lower Vedder formation since 2013 has led to thirteen new drill wells and five workovers with rates ranging from 10-280 bopd. Renewed focus and shallow reservoirs with attendant low costs have allowed multiple development techniques to be tested successfully in a short period of time at the Mount Poso field, realizing significant production growth in a mature field.
AAPG Datapages/Search and Discovery Article #90215 © 2015 Pacific Section AAPG Convention, Oxnard, California, May 3-6, 2015