Crustal structure at the intersection of the Ryukyu Trench with the arc-continent collision in Taiwan: Results from an offshore-onshore seismic experiment
Crustal structure at the intersection of the Ryukyu Trench with the arc-continent collision in Taiwan: Results from an offshore-onshore seismic experiment
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琉球海沟与台湾弧大陆碰撞交汇处的地壳结构：近海陆上地震实验结果
DOI：
10.3319/tao.2001.12.s.231(odp
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发表时间：
2001
影响因子：
0.8
通讯作者：
Francis T. Wu
中科院分区：
文献类型：
--
作者：
E. Hetland;Francis T. Wu
台湾正在进行的造山活动是菲律宾海和欧亚板块碰撞的结果。虽然欧亚板块(EP)上的陆壳结构现在大多已知，但菲律宾海板块(PSP)上的洋壳结构从未被很好地绘制过。利用1995年莫里斯·尤因河巡航期间收集的近岸折射资料，研究了台湾琉球海沟和纵谷EP和PSP之间转换的性质。这些数据是由尤因河的气枪阵列沿着台湾北部海岸外两条大致东西走向的线(尤因河14线和16线)产生的。折射的P波是由19台锐迪克记录仪和L-28传感器采集的，这些传感器安装在台湾尤因16号线的陆上延伸段--台湾中横岛公路上。由于沿海平原的高噪音水平和东海岸附近车站的设备故障，只有从中部范围内9个站反演的数据被认为是可用的。为了获得地壳结构，采用了反演和正演模拟方案，结果表明，莫霍面深度从南澳盆地海平面以下约30公里逐渐增加到中东部山脉下约海平面以下约37公里。此外，北部剖面的模型包含一个远离东海岸的相对低速带，可能与中下地壳一样深。(
The ongoing orogeny in Taiwan is a result of the collision of the Philip pine Sea and the Eurasian Plates. While the structure of the continental crust on the Eurasian Plate (EP) is now mostly known, that of the oceanic crust on the Philippine Sea Plate (PSP) has never been well mapped. Using offshore-onshore refraction data, collected during the RIV Maurice Ewing cruise of 1995, the nature of the transition between the EP and the PSP at the Ryukyu Trench and the Longitudinal Valley, Taiwan was investigated. The data were produced by the air-gun array of the RIV Ewing along two roughly east-west trending lines off the coast of northern Taiwan (RIV Ewing Lines 14and16). The refracted P waves were collected by 19 ReITek re corders with L-28 sensors placed along the Central Cross-Island Highway of Taiwan, which is the onshore extension of Ewing Line 16. Because of high noise levels in the Coastal Plain and equipment failure at stations near the east coast, only data retrieved from nine stations in the Central Range were considered usable. To obtain crustal structure, an inversion and for ward modelling scheme was followed and the results indicate that the Moho discontinuity gradually increases depth from about 30 km below sea level under the Nanao Basin to about 37 km below sea level under the Eastern Central Range. Additionally, the model of the northern profile contains a relatively low velocity zone off the east coast, possibly as deep as the lower to-middle crust. (