Sedimentary basins are prominent in convergent margin studies. Located near the volcanic arc in the forearc region,the forearc basin is relatively well-preserved after intense orogeny,with records of intact information about orogenic processes. This paper illustrates the tectonic setting,formation mechanism,provenance,and sedimentary-structural characteristics of the forearc basins exemplified by well-studied Cenozoic examples. Forearc basins are located between the volcanic arc and the trench-slope break. It can be formed in an extensional environment where normal fault forms a half-graben basin,or in a compressional environment where thrusts of the accretionary wedge serve as a dam to pond sediments. All kinds of sedimentary facies can be developed in the forearc basin located in a continental arc,while hemipelagic-pelagic facies are dominant in that located in an intra-oceanic arc. Terrigenous debris is mainly derived from the proximal volcanic arc and accretionary wedge and enters the basin through rivers,submarine canyons,and collapse. Sediments in the forearc basin usually grow thicker from the basin margin to the center and from the bottom to the top. Subduction of mid-ocean ridge,seamount,oceanic plateau,and fracture zone could affect the structure of subduction zones to various degrees,leading to inversion,exhumation,sedimentary hiatus,sedimentary provenance changing,and depositional environment changing of the forearc basin. The development of the forearc basin is difficult to be summarized by a single model. Thus,when forearc basin is applied to orogeny analysis,multi-disciplinary data should be considered in a comprehensive analysis of basin geological records.
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