Nine depositional systems occur in Deep Sea Drilling Project (DSDP) cores recovered from western Pacific back-arc basins. These include submarine fan, debris flow, silty basinal turbidite, biogenic pelagic silica, biogenic pelagic carbonate, redeposited carbonate, pyroclastic, hemipelagic clay, and pelagic clay depositional systems. Correlation of deposition of these systems to times of basin rifting, associated island arc andesitic volcanism, and uplift of source terranes shows that only biogenic carbonate, pelagic clay, submarine fan, and debris flow processes of sedimentation are correlated to specific tectonic processes. Basin subsidence history controlled by heat flow dissipation controls the preservation potential of biogenic carbonates and pelagic clay. Rate of tec onic uplift in andesitic volcanic sources controls the volume and preserved frequency of turbidites on submarine fans and associated debris-flow wedges. A time delay in fan and debris flow sedimentation following maximum uplift in source terranes is governed by development of mature drainage systems and sediment yield into the back-arc basins.

The other depositional systems are deposited independent of rifting, subsidence, or uplift history because their distribution is controlled more by regional volcanism, wind dispersal, climatic change, latitudinally-defined biologic productivity, and slope instability. The variety of stratigraphic sequences in back-arc basin DSDP cores can be explained better in terms of all these changing variables coupled with tectonic processes. The combination of depositional depth and source-terrane uplift rate are the only tectonic processes which directly influence specific sedimentation events in this particular domain.

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