The Role of Water in High-Temperature Rock Deformation

摘要: The first report of water/hydrolytic weakening silicate minerals was based on the observation that strength quartz decreases significantly in presence water released from talc, confining medium used some high-pressure experiments (Blacic and Griggs 1965). Subsequently, a number researchers have studied this important phenomenon several different minerals. Publications examining influence or protons creep behavior nominally anhydrous are listed Table 1⇓. Initial studies treated water-weakening as an on-off process; is, rocks weak under hydrous conditions but strong conditions. Further investigations, however, demonstrated strengths (NAMs) decrease systematically with increasing hydrogen concentration (Kronenberg Tullis 1984; Kohlstedt et al. 1995; Post 1996; Mei 2000a,b; Karato Jung 2003). View table: 1. Investigations effect water/protons minerals. Two quite approaches been analyzing In model, mechanism is envisioned which hydrolyzes Si-O bonds via reaction Si-O-Si + H2O → Si-OH·OH-Si (Griggs 1967), thus term hydrolytic weakening. As result, glide dislocations becomes easier wet than dry since do not need to be broken if present. case weakening, rate limiting step propagation kinks along dislocations, facilitated by diffusion HOH dislocation cores. resulting velocity assumed proportional 1974). effect, analysis implies …