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Figure 31. East Coyote oil field to Brea-Olinda oil field and the Puente Hills. This cross section shows the most prolific oil-producing section along the Whittier fault, which is located in the footwall block, and the only oil-producing section north of the fault, which is located on the crest of the hanging wall block at the structurally highest part of the Puente Hills anticline. Underlying the Puente A lease in the hanging wall block, oil has been produced from fractured La Vida siltstone, Topanga sandstone and basement metavolcanic rocks (e.g. Puente A-3 and A-6). The metavolcanic rocks have been correlated with the Santiago Peak Volcanics and interpreted to be a pendant in granite and granodiorite batholithic rocks (Yerkes, 1972). This is the only known oil accumulation in these intervals in the northeastern Los Angeles basin. Abundant well and surface data constrain structural relationships. Bedding dips in the La Vida siltstone in the hanging wall block range from 30 to 60 degrees, indicating substantial rotation of the block during uplift. Numerous wells, several of which penetrated definitive contacts of metavolcanic basement rocks against sedimentary rocks, define the location of the Whittier fault from sea level to a depth of more than 7000 feet. See Figure 9 for a larger-scale cross section of the vicinity of the Whittier fault.