“…It is well established that many accretionary settings at this depth are typically water saturated, and that fault zones are universally recognized as good pathways for fl uids (e.g., Kastner et al, 1991). Moreover, although pseudotachylytes are commonly considered to form under dry conditions (Sibson and Toy, 2006), several examples on April 8, 2010 gsabulletin.gsapubs.org Downloaded from of fl uid circulation, prior to (pore fl uid) and after (pore fl uids and fl uids derived from melting of hydrous minerals) pseudotachylyte formation have been described in pseudotachylytes with cataclastic precursors (e.g., Magloughlin, 1989Magloughlin, , 1992Magloughlin, , 2002O'Hara and Huggins, 2005).…”