摘要: We constructed a new free-air gravity anomaly map of the Philippine Sea Plate (PSP) using ship-tracked gravity data from the National Geophysical Data Center (NGDC). Our results show that the isogals trend correlates well with the tectonic structures in the PSP. After removing the gravity induced by sea water from the free-air gravity data, we obtained the regional Bouguer gravity anomaly, which is later used to compute the Moho geometry in the PSP by applying the Parker-Oldenburg iterative method. Our results indicate that in the southern part of the West Philippine Basin (WPB) the crustal thickness is nearly homogeneous with a value of about 5 km, which implies that the WPB is quite stable. The low-amplitude and near-zero free-air gravity anomalies clearly indicate that the whole WPB, except at trenches and island arcs, is nearly in a state of isostatic equilibrium. The average crustal thickness of the Palau Kyushu Ridge (PKR) is more than 10 km. In the eastern PSP the crustal thickness gradually increases eastward. Our results also imply that a relatively thin and low density mantle exists beneath the Parece Vela Basin (PVB) as a consequence of back-arc spreading and serpentinized upwells of the thin crustal thickness. 出版者: Taiwan: 中華民國地球科學學會 出版日期: 2015-06-01 出處: TAO : Terrestrial, atmospheric, and oceanic sciences, 2015-06, Vol.26 (3), p.253-259 資源來源: Airiti Library. Chinese Electronic Periodical Services (CEPS) 版權: 2015. This work is licensed under https://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License. 識別號: ISSN: 1017-0839 識別號: ISSN: 2223-8964 識別號: ISSN: 2311-7680 識別號: EISSN: 2311-7680 識別號: DOI: 10.3319/TAO.2014.11.17.01(T)