The Goodsprings Dolomite is confined to an area of approximately 8,200 sq km in southern Nevada and eastern California. Owing to its general lack of fossils and monotonous lithology, previous workers have mapped the Goodsprings as Cambrian-Devonian undifferentiated.
The purpose of the present study was to subdivide the Goodsprings Dolomite into regionally mappable units and to correlate these units with laterally equivalent, presently recognized, miogeosynclinal formations to the north and west. Results suggest: (1) the Goodsprings contains many well-defined, regionally mappable units; (2) approximately the lower one-half of the formation is lithologically equivalent to the Middle to Upper Cambrian Bonanza King Formation; (3) much of the remaining Goodsprings is lithologically and faunally equivalent to the Upper Cambrian Nopah Formation; (4) in the northeastern part of the outcrop area, strata lithologically equivalent to the Lower Ordovician Pogonip Group (undifferentiated) were found; (5) the uppermost 200 m of Goodsprings is lithologically variable and equivalent in age to the Upper Ordovician Ely Springs Dolomite; however, owing to a lack of lithologic equivalency with the Ely Springs, a new formational name, the “Mountain Springs Formation,” is proposed for these strata; (6) two post–Late Cambrian—pre-Middle Devonian disconformities are indicated, which cause the progressive “pinching-out” of the Pogonip Group and Mountain Springs Formation in a southeasterly direction.
On the basis of these findings, the formational rank of the Goodsprings Dolomite should be dropped.