摘要： The Taiwan Integrated Geodynamic Research program (TAIGER) collected two wide‐angle and reflection seismic transects across the northern Manila subduction zone that provide constraints on the seismic velocity structure of the crust. Two‐dimensional gravity modeling along these two transects shows a significant, relatively high density (3.12 and 3.02 g/cm3) in the fore‐arc region, at the interface between the subducting Eurasian Plate and the accretionary prism in front of the Luzon arc on the overriding Philippine Sea Plate. The anomalous density in this zone is higher than that in the fore‐arc crust and the accretionary prism but lower than that in mantle. Numerous geophysical and geological data, together with numerical models, have indicated that serpentinization of the fore‐arc mantle is both expected and observed. Serpentinization of mantle rocks can dramatically reduce their seismic velocity and therefore their seismic velocity in a density to velocity conversion. Therefore, the source of the high‐density material could be serpentinized fore‐arc mantle, with serpentinization caused by the dehydration of the subducting Eurasian Plate. We interpret that positive buoyancy combined with weak plate coupling forces in the northern Manila subduction zone is resulting in this serpentinized fore‐arc mantle peridotite being exhumed. Key Points Two‐dimensional gravity modeling shows a significant high‐density structure in the fore‐arc region Positive buoyancy and weak plate coupling result in serpentinized peridotite exhumed Exhumed serpentinized materials in the northern Manila subduction zone are found 其他題名： Geophys. Res. Lett 出版者： Washington: Blackwell Publishing Ltd 出版日期： 2015-10-16 出處： Geophysical research letters, 2015-10, Vol.42 (19), p.7977-7982 資源來源： Wiley Journals 版權： 2015. American Geophysical Union. All Rights Reserved. 識別號： ISSN: 0094-8276 識別號： ISSN: 1944-8007 識別號： EISSN: 1944-8007 識別號： DOI: 10.1002/2015GL065705
