Named as upper formation of Gila group for exposures near Sacaton Ranch, about 12 mi southeast of Mammoth, Pinal Co, AZ in Basin-and-Range province. No type locality designated. Is disconformable on Quiburis formation of Gila group. Unconformably underlies Quaternary alluvial deposits. Correlation chart. Geologic map. Block diagrams. Composed of unconsolidated granule to pebble conglomerate made up of feldspar and quartz fragments. Also has fragments of diabase, graywacke, and phyllite. Matrix is sand and some silt. Weakly cemented by lime. Best developed on west side of San Pedro Valley. Maximum thickness of about 250 ft. Has a basal boulder to pebble gravel as much as 20 ft thick that has subround to well-rounded fragments of quartz monzonite, volcanic rocks, Paleozoic limestone, red calcareous mudstone, marble, and gneiss. Laid down in a broad valley cut into the Quiburis formation. Considered Pleistocene.

Source: GNU records (USGS DDS-6; Denver GNULEX).

Sacaton Formation, upper formation of Gila Group of Heindl (1963), is abandoned. Gila geographically restricted from Ray-San Manuel area, eastern Pinal County, Arizona (Basin-and-Range province). Recent mapping shows deposition occurred after inception of the present drainage along the Gila and San Pedro Rivers and not during development of one large structural basin as previously thought. Rocks are here included in unnamed Pleistocene and Holocene gravel, and pediment gravel and soil units.

Source: Publication; Changes in stratigraphic nomenclature, 1972 (USGS Bull. 1394-A, p. A55).