Type locality designated as exposures within 0.25 mi radius of Rye Patch Dam in bluffs of Humboldt River valley, Pershing Co, NV. Defined as deposits of ancient Pleistocene lake that existed in approximate area which was subsequently inundated by Lake Lahontan, and which are younger than Humboldt Valley Soil and older than Cocoon Soil. Maximum thickness is about 30 ft. Most conspicuous feature is resistant calcium-carbonate-cemented bed of pebble gravel in middle part that crops out on west side of Humboldt River few ft above level of Rye Patch Dam spillway. This bed, 5 to 8 ft thick, is shallow-water deltaic deposit. Beneath gravel bed is zone, 5 to 15 ft thick, of lacustrine silt, clay, and locally sand and vitric volcanic ash. Overlying cemented gravel bed is zone, about 12 ft thick of lacustrine silt and clay with intercalated thin bed of colluvium. Overlies Lovelock Formation (new). Underlies Paiute Formation. Age given as Pleistocene.

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

Rye Patch Formation of Morrison and Frye (1965) redescribed as Rye Patch Alloformation as defined in 1983 North American Stratigraphic Code. Stratigraphic chart of allostratigraphic and pedostratigraphic units in Lake Lahontan area shows Rye Patch Alloformation contains Rye Patch Dam tephra bed with normal polarity belonging to Jaramillo Normal Polarity Subchron (0.9 Ma).

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