1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, and 2000. California Geological Survey. This polygon file depicts debris slide slope geomorphic features, defined as coalesced scars of debris flows and debris slides, within the Albion R... California Geological Survey.