Geologic units in Santa Cruz county, California

Additional scientific data in this geographic area

Miocene marine rocks (Oligocene to Pliocene) at surface, covers 36 % of this area

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

Pliocene marine rocks (Miocene to Pleistocene) at surface, covers 17 % of this area

Sandstone, siltstone, shale, and conglomerate; in part Pleistocene and Miocene.

Older Quaternary alluvium and marine deposits (Pleistocene) at surface, covers 11 % of this area

Older alluvium, lake, playa, and terrace deposits.

Eocene marine rocks (Paleocene to Oligocene) at surface, covers 9 % of this area

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

Quaternary alluvium and marine deposits (Pleistocene to Holocene) at surface, covers 8 % of this area

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

Mesozoic granitic rocks, unit 1 (Salinian Block) (Early to Late Cretaceous) at surface, covers 8 % of this area

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

Oligocene marine rocks (Eocene to Miocene) at surface, covers 6 % of this area

Sandstone, shale, and conglomerate; in part Miocene and Eocene.

Schist of various types and ages, unit 6 (Santa Cruz Mountains) (Paleozoic or Mesozoic) at surface, covers 2 % of this area

Schists of various types; mostly Paleozoic or Mesozoic age; some Precambrian.

Oligocene nonmarine rocks, unit 2 (Central and Southern California) (middle Eocene to early Miocene) at surface, covers 0.8 % of this area

Sandstone, shale, and conglomerate; in part Miocene and Eocene.

Quaternary sand deposits, unit 1 (coastal) (Quaternary) at surface, covers 0.6 % of this area

Extensive marine and nonmarine sand deposits, generally near the coast or desert playas

Upper Cretaceous marine rocks, unit 1 (Upper Great Valley Sequence) (Late Cretaceous) at surface, covers 0.5 % of this area

Upper Cretaceous sandstone, shale, and conglomerate

Paleocene marine rocks, unit 1 (Central and Southern California) (Paleocene) at surface, covers 0.5 % of this area

Sandstone, shale, and conglomerate; mostly well consolidated

Mesozoic gabbroic rocks, unit 2 (undivided) (Triassic to Cretaceous) at surface, covers 0.2 % of this area

Gabbro and dark dioritic rocks; chiefly Mesozoic

Limestone of probable Paleozoic or Mesozoic age (Paleozoic to Mesozoic) at surface, covers < 0.1 % of this area

Limestone, dolomite, and marble whose age is uncertain but probably Paleozoic or Mesozoic

Upper Cretaceous and Paleocene marine rocks, undivided (Late Cretaceous to Paleocene) at surface, covers < 0.1 % of this area

Sandstone, shale, and conglomerate