islands provide over 70 % of terrigenous suspended materials to the global ocean, these sediments were intercepted
by marginal seas so that there are no large submarine deepsea fans developed in the western Pacific comparable to
Indian Ocean fans (Wang, 1999, 2004). The wide continental shelves of marginal seas are vulnerable to sea-level
changes and thus might influence the climate. For example, because the South China Sea is a major source of
Model 1. Slab-induced upwelling model
Model 2. Plume injection model
Model 3. Plate kinematic model
-Retreat of backarc plate
Model 4. Asthenospheric flow model 1
-Trench roll back by eastward
asthenospheric current
Model 5. Asthenospheric flow model 2
-Trench roll back by instability of
downgoing asthenospheric flow
Active models
Passive models
Continental plate
Oceanic plate
Mantle flow
Asthenospheric flow
Plate motion
Volcanics
Fault
Spreading axis
Model 6. Slab-pull model
Model 7. Pull-apart model (plan view)
Marginal Seas, Figure 2 Back-arc spreading models for the origin of marginal seas. Models 1–5 are redraw from Tamaki and Honza
(1991).
MARGINAL SEAS
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