Crustal Structure of the Northeastern Taiwan Area from Seismic Refraction Data and Its Tectonic Implications

由折射震測資料探求臺灣東北部地區地殼構造及其在地體構造上之意義

鄭文彬(Win-Bin Cheng) ； 王正松(Chengsung Wang) ； 徐春田(Chuen-Tien Shyu)

《Terrestrial, Atmospheric and Oceanic Sciences》 7卷4期 (1996/12) Pp. 467-487

並列摘要

The southwestern part of the Ryukyu arc-trench system to the west of126°E is obviously bent northwards horizontally.The mechanism of thishorizontal bending has been discussed in the literature,but it is still ambiguous.The West Philippine Basin(WPB)is generally believed to be produced by spreading along the Central Basin Ridge(CBR).However,theCBR does not extend to the northwestern corner of the WPB.Previousgeomagnetic and geomorphological studies suggested that the CBR terminates or is displaced at its northwestern end.However,the detailed pictureis still unclear.In this paper,we have examined bathymetry,gravity andseismicity in and around the northwestern corner of the WPB,and discovered a NE-trending right-handed strike-slip fault system which can be usedto interpret the horizontal bending of the southwestern part of the Ryukyuarc-trench system.A plausible model showing how the right-handed faultsystem results in the bending of the Ryukyu arc-trench system is demonstrated.As the southeastern part of the right-handed strike-slip fault system,the Luzon-Okinawa Fault Zone,which is an obvious fault zone between the Luzon and Okinawa islands,is described in terms of bathymetriccontours and profiles along some cruise lines.The Luzon-Okinawa FaultZone is the main cause of the termination of the CBR.

並列關鍵字

Seismic Refraction ； Ray-Tracing ； P-Wave Velocity Structure ； Coastal Range ； Eastern Flank of the Central Range ； Arc-Arc Collision