Late Ordovician rugose corals of the northern Sierra Nevada, California

Abstract

The shoo fly Complex of Late Devonian and older Paleozoic age is a regionally extensive rock assemblage in the northern Sierra Nevada of northern California. It consists chiefly of a coherent unit of phyllite, quartzose sandstone, and chert, and a melange unit (Hannah and Moores, 1986). Several limestone lenses in the Taylorsville area comprise the Montgomery Limestone (Diller, 1892, 1908; McMath, 1958; Figure 1). The Montgomery was long considered to be Silurian, largely on the basis of corals, brachiopods, and cephalopods (Diller, 1892, 1908; McMath, 1958; Berry and Boucot, 1970; Merriam, 1972). However, recent analyses of the biota indicate an Ashgill (middle Maysvillian–Gamachian) age (Boucot and Potter, 1977; Harris, personal commun. cited in Hannah and Moores, 1986, p. 790; Potter et al., 1990b; present study).