Frictional behavior of pelagic sediments sampled from Cores 38 and 40 of DSDP Site 436. (a, d) Friction coefficient versus displacement curves at a constant slip velocity of 1.3 m/s under normal stresses of 0.7 to 2.0 MPa. Temperature evolution of the fault zone during the run at a normal stress of 1.0 MPa is shown by the red dotted lines. Inserted plots show an enlarged view of the onset of the slip. (b, e) Measured shear stress plotted against applied normal stress at initial peak friction (blue diamonds) and steady-state friction (red circles). Intercepts have been interpreted as due to friction between the Teflon sleeve and the outer surface of the specimen. (c, f) Friction coefficient versus displacement curves at a constant normal stress of 1 MPa and different slip velocities of 0.25 to 1.3 m/s.