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

Figure 6.

Fracture (A) dip and (B) strike from resistivity-at-the-bit image interpretation. Fracture strike is plotted so that the dip direction is 90^o counterclockwise from the strike. An increase in fractures occurs between 380 and 520 mbsf. Orientations appear to be randomly distributed. Note the two zones of fracturing (378-384 and 410-417 mbsf) and the zone of high-resistivity bands (~500 mbsf) associated with intensive deformation, possibly brecciation. The shallower zone of fracturing (378-384 mbsf) may correlate with a fractured zone recorded in the cores of Leg 190 Hole 1173A (382-384 mbsf) but the deeper zone has no such correlation. A steeply dipping fracture would not be expected to correlate at the same depth between two holes spaced 50 m apart, unless it represented part of a subhorizontal zone of high-angle fractures.