The Philippine Sea Plate has an extremely special tectonic background. As an oceanic plate,it is almost entirely surrounded by subduction zones with complex internal tectonic features. On the basis of enormous publish...The Philippine Sea Plate has an extremely special tectonic background. As an oceanic plate,it is almost entirely surrounded by subduction zones with complex internal tectonic features. On the basis of enormous published literature,this paper offers a comprehensive overview of the tectonic and evolution history of the Philippine Basin and the Kyushu-Palau Ridge（KPR） in the Philippine Sea Plate,and discusses the geological features of KPR. Referring to relevant definitions of various ＂ridges＂ stipulated in United Nations Convention on the Law of the Sea,so the KPR is believed to be a remnant arc formed during the opening of the Parece Vela and Shikoku Basins in the Philippine Sea Plate. It is a submarine ridge on oceanic plate rather than a submarine elevation. And thus,it is not a natural component of the Japan continental margin.展开更多
The proto-Philippine Sea Plate(pPSP)has been proposed by several authors to account for the origin of the Mesozoic supra-subduction ophiolites along the Philippine archipelago.In this paper,a comprehensive review of t...The proto-Philippine Sea Plate(pPSP)has been proposed by several authors to account for the origin of the Mesozoic supra-subduction ophiolites along the Philippine archipelago.In this paper,a comprehensive review of the ophiolites in the eastern portion of the Philippines is undertaken.Available data on the geology,ages and geochemical signatures of the oceanic lithospheric fragments in Luzon(Isabela,Lagonoy in Camarines Norte,and Rapu-Rapu island),Central Philippines(Samar,Tacloban,Malitbog and Southeast Bohol),and eastern Mindanao(Dinagat and Pujada)are presented.Characteristics of the Halmahera Ophiolite to the south of the Philippines are also reviewed for comparison.Nearly all of the crust-mantle sequences preserved along the eastern Philippines share Early to Late Cretaceous ages.The geochemical signatures of mantle and crustal sections reflect both mid-oceanic ridge and suprasubduction signatures.Although paleomagnetic information is currently limited to the Samar Ophiolite,results indicate a near-equatorial Mesozoic supra-subduction zone origin.In general,correlation of the crust-mantle sequences along the eastern edge of the Philippines reveal that they likely are fragments of the Mesozoic pPSP.展开更多
The intersection of the Kyushu-Palau Ridge(KPR)and the Central Basin Rift(CBR)of the West Philippine Basin(WPB)is a relic of a trench-trench-rift(TTR)type triple-junction,which preserves some pivotal information on th...The intersection of the Kyushu-Palau Ridge(KPR)and the Central Basin Rift(CBR)of the West Philippine Basin(WPB)is a relic of a trench-trench-rift(TTR)type triple-junction,which preserves some pivotal information on the cessation of the seafloor spreading of the WPB,the emplacement and disintegration of the proto-Izu-Bonin-Mariana(IBM)Arc,and the transition from initial rifting to steady-state spreading of the Parece Vela Basin(PVB).However,the structural characteristics of this triple-junction have not been thoroughly understood.In this paper,using the newly acquired multi-beam bathymetric,gravity,and magnetic data obtained by the Qingdao Institute of Marine Geology,China Geological Survey,the authors depict the topographic,gravity,and magnetic characteristics of the triple-junction and adjacent region.Calculations including the upward continuations and total horizontal derivatives of gravity anomaly are also performed to highlight the major structural features and discontinuities.Based on these works,the morphological and structural features and their formation mechanisms are analyzed.The results show that the last episode amagmatic extension along the CBR led to the formation of a deep rift valley,which extends eastward and incised the KPR.The morphological and structural fabrics of the KPR near and to the south of the triple-junction are consistent with those of the western PVB,manifesting as a series of NNE-SSW-and N-S-trending ridges and troughs,which were produced by the extensional faults associated with the initial rifting of the PVB.The superposition of the above two reasons induced the prominent discontinuity of the KPR in deep and shallow crustal structures between 15°N‒15°30′N and 13°30′N‒14°N.Combined with previous authors’results,we propose that the stress produced by the early spreading of the PVB transmitted westward and promoted the final stage amagmatic extension of the CBR.The eastward propagation of the CBR destroyed the KPR,of which the magmatism had decayed or ceased at that time.The destruction mechanism of the KPR associated with the rifting of the PVB varies along strike the KPR.Adjacent to the triple-junction,the KPR was destroyed mainly due to the oblique intersection of the PVB rifting center.Whereas south of the triple-junction,the KPR was destroyed by the E-W-directional extensional faulting on its whole width.展开更多
The Philippine Sea Plate is located at the convergence zone of the Eurasian Plate,the Pacific Plate,and the Indo-Australian Plate.This paper divides the Philippine Sea Plate into two second-order tectonic units and ei...The Philippine Sea Plate is located at the convergence zone of the Eurasian Plate,the Pacific Plate,and the Indo-Australian Plate.This paper divides the Philippine Sea Plate into two second-order tectonic units and eight third-order tectonic units by summarizing the marine geological,geophysical,and submarine geomorphological data of the Philippine Sea Plate collected for years and referring to the seafloor spreading theory and the trench-arc-basin system.The two second-order tectonic units are the West Philippine Sea block and the Izu-Bonin-Mariana arc-basin system.The former includes the West Philippine Basin,the Huatung Basin,the Daito Basin,and the Palau Basin,while the latter consists of the Kyushu-Palau Ridge,the Shikoku-Parece Vela Basin,the Izu-Bonin Arc,and the Mariana Arc.Furthermore,this study concludes that the Philippine Sea Plate has undergone three stages of tectonic evolution,namely the early stage of the evolution of marginal basins with Cretaceous basement(Early Cretaceous),the middle stage of the spreading of the West Philippine Basin(Eocene),and the late stage of the subduction of the Izu-Bonin-Mariana arc-basin system(Oligocene-present).The Kyushu-Palau Ridge is a window to discover the tectonic evolution of the Philippine Sea Plate due to its unique geographical location.展开更多
Euler vectors of 12 plates, including Philippine Sea plate (PH), relative to a randomly fixed Pacific plate(PA) were determined by inverting the 1122 data from NUVEL-1 global plate motion model, earthquake slip vector...Euler vectors of 12 plates, including Philippine Sea plate (PH), relative to a randomly fixed Pacific plate(PA) were determined by inverting the 1122 data from NUVEL-1 global plate motion model, earthquake slip vectors along Philippine Sea plate boundary, and GPS observed velocities. Euler vectors of Philippine Sea plate relative to adjacent plates are also gained. Our results are well consistent with observed data and can satisfy the geological and geophysical constraints along the Caroline(CR)-PH and PA-CR boundaries. Deformation of Philippine Sea plate is also discussed by using the plate motion Euler parameters.展开更多
Based on the published data of structure geology,geochronology,petrology and isotope geochemistry,the authors of this paper have conducted studies on the tectonic evolution history of Japan arc system and Kyushu-Palau...Based on the published data of structure geology,geochronology,petrology and isotope geochemistry,the authors of this paper have conducted studies on the tectonic evolution history of Japan arc system and Kyushu-Palau ridge（KPR） . The studies show that the initial Japan arc system was resulted from the subduction of ancient Pacific plate beneath Eurasian Plate in Permian. It was part of an Andean-type continental volcanic arc which occurred in the offshore in the east of Asian during late Mesozoic era. The formation of tertiary back-arc basin（Japan Sea） resulted in the fundamental tectonic framework of the present arc system. Since Quaternary the system has been lying at E-W compression tectonic setting due to the eastward subduction of Amur Plate. It is expected that Japan arc system will be juxtaposed with Asian continent,which is similar to the present Taiwan arc system. The origin of Philippine Sea Plate（PSP） is still in debate. Some studies argued that it is a trapped oceanic crust segment,while the others insisted that it is a back-arc basin accompanied with ancient IBM arc. However,it is all agreed that the tectonic evolution of PSP started since 50 Ma,i.e.,PSP has drifted from the site around equator at 50 Ma to the present site,and the subduction of PSP along Nankai trough-Ryukyu Trench beneath the Japan arc system during 6–2 Ma led to the formation of the present Ryukyu arc system. Of the PSP,the KPR has been found with the oldest rocks formed at 38 Ma. Combining with its geochemical characteristics of oceanic arc tholeiite,it is suggested that KPR is an intraoceanic volcanic arc,more specifically,a relic arc（i.e.,rear arc of the ancient IBM） after rifting of ancient IBM. In addition,Amami-Daito province is of arc tectonic affinity,but has been affected by mantle plume. Therefore,based on their respective tectonic evolution history and geochemical characteristics of rock samples,it is inferred that there is no genetic relationship between Japan arc system and KPR. It is noted that rocks reflecting continental crust basement feature have been collected on the northern tip of KPR,which may be related to the process of KPR accreting on Japan arc,but the arc-continent accretion process are still at initial stage of modern continental crust accretion model. However,due to the scarcity of data of the northern tip of KPR,crustal structure of this location and its adjacent Nankai trough need to be further constrained by geophysical studies in the future.展开更多
基金The National Basic Research Program (973) of China under contract No. 2007CB41170301Special Fund for Marine Scientific Research in the Public Interest under contract Nos 200805078, 201205003 and 201205037
文摘The Philippine Sea Plate has an extremely special tectonic background. As an oceanic plate,it is almost entirely surrounded by subduction zones with complex internal tectonic features. On the basis of enormous published literature,this paper offers a comprehensive overview of the tectonic and evolution history of the Philippine Basin and the Kyushu-Palau Ridge（KPR） in the Philippine Sea Plate,and discusses the geological features of KPR. Referring to relevant definitions of various ＂ridges＂ stipulated in United Nations Convention on the Law of the Sea,so the KPR is believed to be a remnant arc formed during the opening of the Parece Vela and Shikoku Basins in the Philippine Sea Plate. It is a submarine ridge on oceanic plate rather than a submarine elevation. And thus,it is not a natural component of the Japan continental margin.
基金Funding support from the Department of Science and Technology,University of the Philippines-Diliman,National Institute of Geological Sciences and National Research Council of the Philippines
文摘The proto-Philippine Sea Plate(pPSP)has been proposed by several authors to account for the origin of the Mesozoic supra-subduction ophiolites along the Philippine archipelago.In this paper,a comprehensive review of the ophiolites in the eastern portion of the Philippines is undertaken.Available data on the geology,ages and geochemical signatures of the oceanic lithospheric fragments in Luzon(Isabela,Lagonoy in Camarines Norte,and Rapu-Rapu island),Central Philippines(Samar,Tacloban,Malitbog and Southeast Bohol),and eastern Mindanao(Dinagat and Pujada)are presented.Characteristics of the Halmahera Ophiolite to the south of the Philippines are also reviewed for comparison.Nearly all of the crust-mantle sequences preserved along the eastern Philippines share Early to Late Cretaceous ages.The geochemical signatures of mantle and crustal sections reflect both mid-oceanic ridge and suprasubduction signatures.Although paleomagnetic information is currently limited to the Samar Ophiolite,results indicate a near-equatorial Mesozoic supra-subduction zone origin.In general,correlation of the crust-mantle sequences along the eastern edge of the Philippines reveal that they likely are fragments of the Mesozoic pPSP.
基金This study was funded by the projects initiated by the China Geological Survey(DD20191003,DD20190236 and DD20190205).
文摘The intersection of the Kyushu-Palau Ridge(KPR)and the Central Basin Rift(CBR)of the West Philippine Basin(WPB)is a relic of a trench-trench-rift(TTR)type triple-junction,which preserves some pivotal information on the cessation of the seafloor spreading of the WPB,the emplacement and disintegration of the proto-Izu-Bonin-Mariana(IBM)Arc,and the transition from initial rifting to steady-state spreading of the Parece Vela Basin(PVB).However,the structural characteristics of this triple-junction have not been thoroughly understood.In this paper,using the newly acquired multi-beam bathymetric,gravity,and magnetic data obtained by the Qingdao Institute of Marine Geology,China Geological Survey,the authors depict the topographic,gravity,and magnetic characteristics of the triple-junction and adjacent region.Calculations including the upward continuations and total horizontal derivatives of gravity anomaly are also performed to highlight the major structural features and discontinuities.Based on these works,the morphological and structural features and their formation mechanisms are analyzed.The results show that the last episode amagmatic extension along the CBR led to the formation of a deep rift valley,which extends eastward and incised the KPR.The morphological and structural fabrics of the KPR near and to the south of the triple-junction are consistent with those of the western PVB,manifesting as a series of NNE-SSW-and N-S-trending ridges and troughs,which were produced by the extensional faults associated with the initial rifting of the PVB.The superposition of the above two reasons induced the prominent discontinuity of the KPR in deep and shallow crustal structures between 15°N‒15°30′N and 13°30′N‒14°N.Combined with previous authors’results,we propose that the stress produced by the early spreading of the PVB transmitted westward and promoted the final stage amagmatic extension of the CBR.The eastward propagation of the CBR destroyed the KPR,of which the magmatism had decayed or ceased at that time.The destruction mechanism of the KPR associated with the rifting of the PVB varies along strike the KPR.Adjacent to the triple-junction,the KPR was destroyed mainly due to the oblique intersection of the PVB rifting center.Whereas south of the triple-junction,the KPR was destroyed by the E-W-directional extensional faulting on its whole width.
基金funded by the projects initiated by the China Geological Survey(DD20190205,DD20160137,DD20191003)the National Natural Science Foundation of China(U20A20100,42002235)the Pilot National Laboratory for Marine Science and Technology(Qingdao)(JCZX202026)。
文摘The Philippine Sea Plate is located at the convergence zone of the Eurasian Plate,the Pacific Plate,and the Indo-Australian Plate.This paper divides the Philippine Sea Plate into two second-order tectonic units and eight third-order tectonic units by summarizing the marine geological,geophysical,and submarine geomorphological data of the Philippine Sea Plate collected for years and referring to the seafloor spreading theory and the trench-arc-basin system.The two second-order tectonic units are the West Philippine Sea block and the Izu-Bonin-Mariana arc-basin system.The former includes the West Philippine Basin,the Huatung Basin,the Daito Basin,and the Palau Basin,while the latter consists of the Kyushu-Palau Ridge,the Shikoku-Parece Vela Basin,the Izu-Bonin Arc,and the Mariana Arc.Furthermore,this study concludes that the Philippine Sea Plate has undergone three stages of tectonic evolution,namely the early stage of the evolution of marginal basins with Cretaceous basement(Early Cretaceous),the middle stage of the spreading of the West Philippine Basin(Eocene),and the late stage of the subduction of the Izu-Bonin-Mariana arc-basin system(Oligocene-present).The Kyushu-Palau Ridge is a window to discover the tectonic evolution of the Philippine Sea Plate due to its unique geographical location.
基金This work was supported by Project of Mechanism and Prediction of Continental Strong Earthquake (Grant No. 5-13-04-06).
文摘Euler vectors of 12 plates, including Philippine Sea plate (PH), relative to a randomly fixed Pacific plate(PA) were determined by inverting the 1122 data from NUVEL-1 global plate motion model, earthquake slip vectors along Philippine Sea plate boundary, and GPS observed velocities. Euler vectors of Philippine Sea plate relative to adjacent plates are also gained. Our results are well consistent with observed data and can satisfy the geological and geophysical constraints along the Caroline(CR)-PH and PA-CR boundaries. Deformation of Philippine Sea plate is also discussed by using the plate motion Euler parameters.
基金The China Ocean Mineral Resources R & D Association (COMRA),The Basic Research Project of the Ministryof Science and Technology under contract No. 2008 FY220300the National Natural Science Foundation of China undercontract No. 40609034
文摘Based on the published data of structure geology,geochronology,petrology and isotope geochemistry,the authors of this paper have conducted studies on the tectonic evolution history of Japan arc system and Kyushu-Palau ridge（KPR） . The studies show that the initial Japan arc system was resulted from the subduction of ancient Pacific plate beneath Eurasian Plate in Permian. It was part of an Andean-type continental volcanic arc which occurred in the offshore in the east of Asian during late Mesozoic era. The formation of tertiary back-arc basin（Japan Sea） resulted in the fundamental tectonic framework of the present arc system. Since Quaternary the system has been lying at E-W compression tectonic setting due to the eastward subduction of Amur Plate. It is expected that Japan arc system will be juxtaposed with Asian continent,which is similar to the present Taiwan arc system. The origin of Philippine Sea Plate（PSP） is still in debate. Some studies argued that it is a trapped oceanic crust segment,while the others insisted that it is a back-arc basin accompanied with ancient IBM arc. However,it is all agreed that the tectonic evolution of PSP started since 50 Ma,i.e.,PSP has drifted from the site around equator at 50 Ma to the present site,and the subduction of PSP along Nankai trough-Ryukyu Trench beneath the Japan arc system during 6–2 Ma led to the formation of the present Ryukyu arc system. Of the PSP,the KPR has been found with the oldest rocks formed at 38 Ma. Combining with its geochemical characteristics of oceanic arc tholeiite,it is suggested that KPR is an intraoceanic volcanic arc,more specifically,a relic arc（i.e.,rear arc of the ancient IBM） after rifting of ancient IBM. In addition,Amami-Daito province is of arc tectonic affinity,but has been affected by mantle plume. Therefore,based on their respective tectonic evolution history and geochemical characteristics of rock samples,it is inferred that there is no genetic relationship between Japan arc system and KPR. It is noted that rocks reflecting continental crust basement feature have been collected on the northern tip of KPR,which may be related to the process of KPR accreting on Japan arc,but the arc-continent accretion process are still at initial stage of modern continental crust accretion model. However,due to the scarcity of data of the northern tip of KPR,crustal structure of this location and its adjacent Nankai trough need to be further constrained by geophysical studies in the future.
