William V. Sliter, Robert J. McLaughlin, Gerta Keller, William R. Evitt; Paleogene accretion of Upper Cretaceous oceanic limestone in northern California. Geology ; 14 (4): 350–353. doi: https://doi.org/10.1130/0091-7613(1986)14<350:PAOUCO>2.0.CO;2
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Blocks of pelagic limestone, tectonically incorporated into coastal terrane melange, contain planktonic foraminifers of early Campanian to middle Maestrichtian age (82-69 Ma) typical of low latitudes between 20°N and 20°S. Carbonate concretions from the sheared terrigenous matrix of the melange yield temperate, middle-latitude planktonic foraminifers and dinoflagellates of middle to late Eocene age (49-41 Ma). The pelagic limestone and the basaltic substrate presumably formed on the eastern flank of the Pacific-Farallon spreading ridge in a low-latitude zone of high productivity and migrated northward on the Farallon plate until about 40 Ma when they initially encountered terrigenous turbidites north of lat. 30°N. Northward translation and final accretion were completed by about 25 Ma.