Crustal Structure of Philippine Sea Plate:Insights from Gravity Inversions Constrained by Deep Seismic
Huang Ziqiang
Wu Zhaocai
Fang Yinxia
Xu Mingju
Zhang Jialing
Abstract：In order to understand the deep structure of the geological tectonic units of the Philippine Sea plate and the crustal feature of the Kyushu-Palau Ridge,this paper uses satellite gravity anomaly,combined with the bathymetry,sediment thickness and oceanic crust age data in the study area to correct the gravity effects of sediment and thermal disturbance.The Moho depth and crustal thickness of the Philippine Sea plate were calculated by combining Moho depth data from OBS profiles cross the KPR as constraints.The results show that the overall crustal thickness of the Philippine Sea plate is characterized by a gradual increase from west to east and from south to north.The Moho depth of the West Philippine Basin is about 10 km,with a crustal thickness of about 4 km.The average crustal thickness of the Parece Vela Basin is about 7 km,which is larger than that of the older West Philippine Basin.The crustal thickness of the Kyushu-Palau Ridge is 14 km at the maximum.In the 18°—19°N segment of the KPR,the crust is about 8 km,which is similar to the normal oceanic crust thickness in the Parece Vela Basin.There is no significant thickening crust.The crustal properties of the KPR are oceanic crust that has been thickened by back-arc magmatism,rather than mature island arc crust.
Keywords：West Philippine BasinKyushu-Palau RidgeParece Vela Basincrustal thicknesscrustal propertymarine geology
Publication Date：2025-01-14
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：12( 234-245 )