Tectonics of the southern tip of the Parece Vela Basin, Philippine Sea Plate
Tectonics of the southern tip of the Parece Vela Basin, Philippine Sea Plate
复制标题
DOI：
10.1016/j.tecto.2007.11.017
复制
发表时间：
2009-03
期刊：
影响因子：
2.9
通讯作者：
K. Okino;Y. Ohara;T. Fujiwara;Sang‐Mook Lee;K. Koizumi;Y. Nakamura;Shiguo Wu
中科院分区：
文献类型：
--
作者：
K. Okino;Y. Ohara;T. Fujiwara;Sang‐Mook Lee;K. Koizumi;Y. Nakamura;Shiguo Wu
我们报告新的地球物理和岩石学数据收集在菲律宾海的Parece Vela盆地南端。晚渐新世至中中新世形成于原马里亚纳弧沟系之后的Parece Vela盆地为研究菲律宾海弧后盆地形成的性质以及弧与弧后岩浆活动的关系提供了良好的机会。卫星测高得到的区域水深图显示，盆地南端目前位于雅普弧沟系以西，具有独特的形态和构造特征，包括：1）缺乏扩张中心或其踪迹，2）浅平均深度，3）神秘的弯曲结构。我们新收集的高分辨率测深数据显示，在9°20′N以北存在类似于Parece Vela盆地中心的扩张组构。因此，现在的雅普弧和弧后区域代表了帕雷斯贝拉盆地北方和中部早期东西向扩张和随后的东北-西南向扩张所产生的海底的西半部，而东部对应区域现在位于西马里亚纳海脊以西。与北方帕雷斯贝拉盆地不同，南部似乎没有证据表明扩张中心有系统地扩展。相反，两个裂谷段，一个从帕雷斯贝拉盆地中部延伸，另一个位于西部残余弧（九州-帕劳海岭）内，在盆地南端重叠，产生了复杂的海底，包括弯曲的深海和变形的地形高点。
We report new geophysical and petrological data collected at the southern tip of the Parece Vela Basin in the Philippine Sea. The Parece Vela Basin, which was formed as a backarc basin behind proto Mariana arc–trench system from late Oligocene to middle Miocene, provides us a good opportunity to study the nature of successive backarc basin formations in the Philippine Sea and the relationship between arc and backarc magmatisms. Regional bathymetric map derived from satellite altimetry shows that the southern tip of the basin, now located just west of the Yap arc–trench system, has unique morphological and tectonic features which include: 1) the absence of spreading center or its trace, 2) shallow average depth, and 3) enigmatic curved structures. Our newly collected high-resolution bathymetric data reveal that the spreading fabric similar to the central Parece Vela Basin exists to the north of 9°20′N. Thus it appears that the present-day Yap arc and backarc region represent the western half of the seafloor that was produced by the early E–W and the following NE–SW spreading in the northern and central Parece Vela Basin, and that the eastern counterpart now lies west of the West Mariana Ridge. Unlike the northern Parece Vela Basin, there appears to be no evidence for a systematic propagation of spreading center in the southern part. Instead two rift segments, one which extends from the central Parece Vela Basin and the other which lies within the western remnant arc (Kyushu–Palau Ridge), overlap at the southern tip of the basin, producing a complex seafloor that includes curvilinear deeps and deformed topographic highs.