ODP Leg 196: Deformation and Fluid Flow Processes in the Nankai Trough Accretionary Prism

Figure 12.

Fracture (A) dip and (B) strike from resistivity-at-the-bit image interpretation, Leg 196 Hole 808I. Fracture strike is plotted so that the dip direction is 90° counterclockwise from the strike (right-hand rule). C. Fault frequency from core analysis, Leg 131 Site 808. Fracture intensity at Hole 808I increases markedly at the frontal thrust zone (389-414 mbsf), fractured interval (559-574 mbsf), and slightly at the décollement zone (~937-965 mbsf). All three zones coincide with increases in fault frequency identified within cores (C), although the frontal thrust zone appears to be slightly shallower in Hole 808C (Leg 131). Fractures are predominantly east-northeast-west-southwest striking, particularly within the frontal thrust zone and fractured interval. Fractures are more randomly orientated at depths >600 mbsf, with a dominant north-south orientation within the décollement zone. Fractures are dominantly south-dipping within the frontal thrust zone and major fractured interval and west-dipping within the décollement zone