Abstract

Data from a series of measured sections of Devonian and Mississippian strata have been assembled as a shelf-to-basin transect. This transect suggests that there was a Devonian shelf margin in the central Sacramento Mountains and that an Early Mississippian shelf margin formed in the northern Sacramento Mountains and prograded slightly beyond the buried Devonian shelf margin. Five depositional sequences are identified and described within this Early Mississippian shelf complex, the Lake Valley Shelf: (1) Caballero, (2) Andrecito, (3) reefal Lake Valley (Alamogordo-Nunn-Tierra Blanca-Table Top), (4) Arcente and (5) Doña Ana. Four changes in nomenclature are proposed for the seven previously named members of the Lake Valley Formation: (1) change Andrecito Member to Andrecito Formation; (2) change Arcente Member to Arcente Formation; (3) change Doña Ana Member to Doña Ana Formation; (4) restrict the name Lake Valley to include the Alamogordo, Nunn, Tierra Blanca and Table Top members only.