A thick marine turbidite succession, dominantly coarse sandstone, underlies the southern part of the San Joaquin Valley. Sands are pebbly to fine grained, commonly poorly sorted, quartzose to arkosic, and are interbedded with dark shales bearing deep-water foraminifers. Graded bedding is common and, with the depths of 2,000 to 6,000 ft (610 to 1,830 m) implied by the fauna, is taken to indicate a turbidity-current origin for most of the sands. The upper, middle and lower Miocene turbidite section was revealed by extensive coring at Paloma, and is similar to the more widespread and oil and gas productive upper Miocene Stevens sandstone.

The central-basin Stevens was deposited as channel sands on deep-sea fans derived from several discrete troughs or canyons on the eastern and southeastern margin of the basin prior to their burial by prograding Santa Margarita sand. Sand channels and lobes in the Bakersfield arch area were controlled locally by compaction structures. The rising Paloma anticline deflected Stevens sands for a time and the very last sands were guided also by incipient folds on the outer Bakersfield arch. Coarse Stevens conglomerates and sands shed from the emergent Temblor Range were deflected by the Buena Vista Hills, Elk Hills, and other anticlinal shoals and were deposited in intervening gaps as thick oil-productive channel sands. They merge with sands from the east side in flowing axially into the di tal northwestern basin.

Facies recognized in the subsurface include a meander-channel facies developed in the prograded muddy slope area upstream from the massive braided-sand facies.