Figure F7. A schematic model of consolidation in the upper and lower Shikoku Basin facies across the trench from Sites 1173 to 1174 in the Muroto Transect (from Bangs and Gulick, this volume). Blue sections represent underconsolidated sediment with relatively high permeability. Dark brown represents the compacted layer that develops between the upper Shikoku Basin to lower Shikoku Basin facies boundary and the stratigraphic equivalent of the décollement zone. Arrow represents focused fluid flow. Initial trench wedge accumulation causes a compacted layer (with presumed low relative permeability) to form in the top of the lower Shikoku Basin facies as fluids are expelled and are able to move through the underconsolidated upper Shikoku Basin facies. Compaction and fluid expulsion from the upper Shikoku Basin facies midway between Site 1173 and the deformation front causes an overpressured décollement zone to develop below the compacted layer.