PSAAPG 100th Anniversary Meeting PUENTE HILLS FIELD TRIP,
Sept. 15, 2024; 9AM to ~ 2PM
The Los Angeles Basin Geological Society, in celebration of the 100th anniversary of the Pacific Section AAPG, will host a fieldtrip to examine key components of the basin’s petroleum system, as exposed in the Puente Hills trend of southern California.
The Los Angeles Basin (LAB) is the most productive petroliferous basin in the world per volume or surface area. The four members of the Miocene Puente Formation – in ascending order: La Vida, Soquel, Yorba, and Sycamore Canyon – comprise >8,900’ of stacked source and reservoir in oil fields along the north-dipping dip-slip/reverse Whittier Fault Zone, and a much greater stratigraphic thickness exists in the basin-center. This succession represents the principal phase of subsidence and deep marine sedimentation in the LAB. A northern and eastern igneous provenance fed a set of submarine fan complexes in the southern San Gabriel Valley, across what would become the Whittier Fault System and the Puente Hills, into the Fullerton Embayment and thence into the LAB proper. Water depth during deposition was greater than 3,000’, with accommodation space exceeding available sediment flux, a condition not overcome until post-Miocene sediment delivery gradually filled the basin.
A striking feature of the Puente Fm. is its source-rock-to-reservoir rock capability: the organic rich mudstones, deeply buried in the LAB, generated hydrocarbons which migrated updip and along faults, then became trapped in tectonically active and complex structural and stratigraphic geometries, with the Sycamore Canyon and Pliocene Fernando Formation serving as the principal reservoirs of the Brea-Olinda, Sansinena, and Whittier fields (425MM cumulative oil). The field trip will examine exposures of the La Vida and Soquel source rocks, the Sycamore Canyon sandstones, and will include impressive examples of active tectonism relating to the Brea-Olinda oil field and the hanging wall structure of the Whittier Fault System, among other compelling features.
Nearby suggestions for food:
Rick’s Drive in and out (Breakfast too!)
Zumaya’s Mexican Cafe (great breakfast, delicious food!)
Cocktails
Guild Hall | Gastropub in CA – Lisa’s favorite