Cover Image Credits

The article by Coleman and others titled “New Idria serpentinite protrusion, Diablo Range, California: from upper mantle to surface” (p. 533–560) synthesizes geologic, geophysical, geochemical, and rheological constraints on the mantle-to-crustal occurrence of a serpentinite protrusion in central California. Metasomatism of detached upper mantle abyssal peridotite, subsequent plastic mobile protrusion of the New Idria serpentinite diapir, and ultimate breaching of the Earth’s surface was a direct consequence of the development of the San Andreas transform margin, migration of the Mendocino Triple Junction, and associated transpressional forces across the plate boundary.

Explanation of cover figure: This figure shows a geologic map of the New Idria serpentinite protrusion and surrounding area in the Diablo Range of central California. The serpentinite diapir occupies the crest of the Coalinga antiform and surrounding faults mark the exhumed trace of the Coast Range fault. The figure has been modified from Tsujimori and others (2007a).