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Geologic units in San Joaquin county, California

Additional scientific data in this geographic area

Franciscan melange (Jurassic to Cretaceous) at surface, covers 52 % of this area

Melange of fragmented and sheared Franciscan complex rocks.

Lithology: melange

Upper Cretaceous marine rocks, unit 1 (Upper Great Valley Sequence) (Late Cretaceous) at surface, covers 22 % of this area

Upper Cretaceous sandstone, shale, and conglomerate

Franciscan Complex, unit 1 (Coast Ranges) (Jurassic to Cretaceous) at surface, covers 8 % of this area

Franciscan complex: Cretaceous and Jurassic sandstone with smaller amounts of shale, chert, limestone, and conglomerate. Includes Franciscan melange, except where separated--see KJfm.

Miocene marine rocks (Oligocene to Pliocene) at surface, covers 5 % of this area

Sandstone, shale, siltstone, conglomerate and breccia; in part Pliocene and Oligocene.

Eocene marine rocks (Paleocene to Oligocene) at surface, covers 5 % of this area

Shale, sandstone, conglomerate, and minor limestone; in part Oligocene and Paleocene.

Plio-Pleistocene and Pliocene loosely consolidated deposits (Miocene to Pleistocene) at surface, covers 2 % of this area

Pliocene and/or Pleistocene sandstone, shale, and gravel deposits; in part Miocene.

Miocene nonmarine rocks (Oligocene to Pleistocene) at surface, covers 2 % of this area

Sandstone, shale, conglomerate, and fanglomerate; in part Pliocene and Oligocene.

Paleocene marine rocks, unit 1 (Central and Southern California) (Paleocene) at surface, covers 0.6 % of this area

Sandstone, shale, and conglomerate; mostly well consolidated

Quaternary alluvium and marine deposits (Pliocene to Holocene) at surface, covers < 0.1 % of this area

Alluvium, lake, playa, and terrace deposits; unconsolidated and semi-consolidated. Mostly nonmarine, but includes marine deposits near the coast.