![]() ![]() All maps were drawn using SRTM and GEBCO with plate boundary data. Black and purple lines are subduction zones and trench-linked strike-slip faults, respectively. Plate names: AM, Amur OK, Okhotsk PS, Philippine Sea AU, Australian SU, Sundaland NA, North American PA, Pacific YMC, Yukutat microcontinent. Abbreviations: SSF, Sibuyan Sea Fault MT, Manila Trench PT, Philippine Trench ELT, East Luzon Trough. Fault names: DF, Denali BRF, Boarder Ranges CSEF, Chugach St. (B) The Great Sumatra Fault system (GSF) along the Java–Sumatra Trench (JST). (A) The Median Tectonic Line (MTL) active fault system in southwestern Japan, related to oblique subduction of the Philippine Sea Plate (PS) along the Nankai Trough (NT). Modern examples of trench-linked strike-slip faults. In this paper, I try to review some of representative strike-slip basins along convergent margins, especially focusing on basin formation and filling processes, as the first step for comprehensive understandings of the tectono-sedimentary evolution in strike-slip basins. Since many local examples were collected after the 1980s, advanced research techniques including subsurface exploration including seismic survey and borehole drilling, analog experiment, and numerical simulation revealed that basin formation and filling processes were not simple but variable. Strike-slip basins thus present a wide diversity in terms of their geometry, evolution, and filling processes. However, the basin geometry is quite different from that of the Ridge Basin, whose shape is more elongated with a length of more than 300 km and a width of less than 20 km, and whose southern margin has been truncated by post-depositional strike-slip fault displacement. The Izumi Group of the Cretaceous turbidite successions in southwestern Japan has the same characteristics in the sedimentary succession as the Ridge Basin, and is therefore considered to contain strata that were deposited in a strike-slip basin. Their basin lengths are typically about three times longer than the basin widths. Sedimentary successions of archetypal examples of strike-slip basins, such as the Ridge Basin in California, have been characterized in terms of the dominance of axial sediment supply and continuous depocenter migration in a direction opposite to that of the sediment supply. Sedimentary strata deposited in these basins record the history of lithospheric response to the convergence. Strike-slip faulting is one of the most important mechanisms of sedimentary basin formation at plate convergent margins, where localized extension can cause topographic depressions. The degree of shortening and uplift or extension and subsidence depends on the modes of convergence between oceanic plates, island arcs, and continental crusts. They include areas of compression accompanied by thrusting, mountain building, and related foreland/forearc basin development, and also areas of strike-slip movement associated with transpressional uplift, transtensional subsidence, or pure strike-slip displacement. Plate convergent margins are areas of concentrated lithospheric stress. ![]()
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