Pg. 12 (fig. 1), 14-15, pls. 1-3. Mesquite schist. Chlorite-quartz-albite-sericite schist; dark steel gray when fresh, weathers to light silvery gray; prominently and thinly bedded; uppermost 500 feet contains many interbeds of fine crystalline limestone, some as much as 10 feet thick. Total thickness about 4,500 feet. Schist dips east under Garlock series (new); contact sharp, concordant; probably a disconformity. Columnar section shows Mesquite schist younger than Rand schist. Age is Precambrian(?).
Exposed in Mesquite Canyon in El Paso Mountains, Saltdale quadrangle, Kern Co., southern CA.

Source: US geologic names lexicon (USGS Bull. 1200, p. 2480-2481).

Pg. 9, 10, geologic time scale (inside front cover). Mesquite Schist of Dibblee (1952). Phyllite sample from a sericite, quartz-plagioclase(?), epidote(?) rock, on west side of Mesquite Canyon along road at boundary between sec. 17 and 18, T. 29 S., R. 39 E., Lat. 35 deg. 24 min. 58 sec. N., Long. 117 deg. 49 min. 31 sec. W., Garlock quadrangle, Kern County, California, yielded a K-Ar age of 189 +/-5 Ma (whole-rock). Age calculated using decay constants of Steiger and Jager, 1977 (Earth Planet. Sci. Letters, v. 36, p. 359-362). Age is minimum time of metamorphism [close to Triassic-Jurassic boundary (195 to 190 Ma)]; may have been lowered by thermal effects from nearby large granitoid plutons.

Source: Publication.