The roles of quartz and water in controlling unstable slip in phyllosilicate-rich megathrust fault gouges

Earth, Planets and Space

Table 1 List of experiments, conditions and key data

Experiment	Material (ill%/qtz%)	σ_n^eff(MPa)	T(°C)	P_f(MPa)	V(μm/s)	Final μ	Final gouge thickness (mm)	Final shear displacement (mm)	Final γ	Stick-slip (Y/N)
RSRS73^a	65/35	170	150	100	10-100-10-1-10-100-10	0.68	0.62	39.9	64	N
RSRS07^a	65/35	170	200	100	10-100-10-1-10-100-10	0.79	0.46	49.2	49	N
RSRS16^a	65/35	170	250	100	10-100-10-1-10-100-10	0.69	0.59	40.1	68	N
RSRS09^a	65/35	170	300	100	10-100-10-1-10	0.77	0.23	23.6	102	Y, at 1 and 10 μm/s
RSRS38^a	65/35	170	350	100	10-100-10-1-10-100	0.81	0.64	33.9	53	Y, at 10 and 100 μm/s
RSRS39^a	65/35	170	400	100	10-100-10-1-10-100	0.89	0.48	35.0	73	Y, at 10 and 100 μm/s
RSRS40^a	65/35	170	450	100	10-100-10-1-10-100-10	0.91	0.52	40.6	78	N
RSRS43^a	65/35	170	500	100	10-100-10-1-10-100-10	0.95	0.66	47.5	72	N^d
RSRS65^a	65/35	170	200	Dry	10-100-10-1-10-100-10	0.75^b	0.68	40.2	59	N
RSRS64^a	65/35	170	350	Dry	10-100-10-1-10-100-10	0.84^b	0.80	40.3	50	N
RSRS66	65/35	170	500	Dry	10-100-10-1-10-100	0.74^c	0.74	30.9	42	Y, at 10 and 100 μm/s^d
RSRS86	65/35	170	500	Dry	10-100-10-1-10-100	0.51^c	0.88	26.7	11	Y, at 10 and 100 μm/s
RSI1	94/6	170	200	100	10-100-10-1-10-100-10	0.53	0.80	40.1	50	N
RSI2	94/6	170	350	100	10-100-10-1-10-100-10	0.69	0.69	38.6	56	Y, at 10 and 100 μm/s
RSI3	94/6	170	500	100	10-100-10-1-10-100-10	0.74	0.58	40.2	69	Y, at 100 μm/s

σ_n^eff = effective normal stress; T = temperature; P_f = pore fluid pressure; V = sliding velocity; μ = coefficient of friction defined as μ = τ / σ_n^eff and γ = shear strain. ^aReported previously by Den Hartog et al. (2012a); ^bslightly different values than reported in Den Hartog et al. (2012a) due to improved corrections; ^cthese values are affected by vigorous stick-slip behaviour; ^doscillations just after the (apparent) yield point.