Abstract

The Carmelo Formation at Point Lobos State Reserve, on the central coast of California, provides an excellently exposed example of conglomeratic submarine-canyon fill. The unit fills a valley incised into Upper Cretaceous granodiorite and a sparse fossil assemblage consistently indicates Paleogene deposition in upper bathyal depths (Bowen, 1965; Nili-Esfahani, 1965; Hill, 1981; Clark, 1997; Burnham, 2005).

The submarine canyon probably originated somewhere in southern California. Geologists generally agree that the underlying granodiorite crystallized as part of a southern extension of the Sierra Nevada and subsequently underwent translation to the northwest with the Miocene establishment of the San Andreas Fault. Pebbles in the canyon fill are largely of volcanic origin, and some have affinities to volcanic rocks in southern California.

Eight separate sections comprise this paper. The first describes the lithologic types and facies associations and successions that compose the canyon fill. The second and third provide strike and dip sections, respectively, through a large exposure of the conglomerate. The fourth illustrates the complexity that exists on a fine scale in the conglomerate. The fifth section documents the stratigraphic complexity at a larger scale and the consequences of early and late deformation. The sixth section examines in detail the facies successions in two systematically fining-up successions, and the final two sections describe the complexity that can exist adjacent to the canyon wall.