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进行这次海洋地磁测量是为了研究台湾东北部海域主要地质构造带的特征。据这次磁测推论,在大陆架以下,中生代或年代更老的火成岩基底起伏很大。地磁和地质资料表明有一个更新世侵入岩和火山岩露头带从台湾北部沿着大陆架的边缘延伸到钓鱼岛诸岛,组成台湾—实道褶皱带的南段。这种更新世侵入岩能够确定台湾—实道褶皱带新第三纪和老第三纪沉积发生褶皱的时代。磁场资料表明火山形成的琉球内弧位于台湾附近的冲绳海槽的中心线上,显然,它与第四纪火山组成的内弧北段是连续的。这种火山作用被认为是代表边缘海形成的初期阶段。平静而振幅低的负异常及剩余磁场等值线与地形特征相吻合表明琉球岛弧的主脊距台湾很近。向北显著弯曲的琉球岛弧以及东经122°与123°之间相关的剩余磁场等值线被解释为是由于主要断层水平错断的结果。
This marine geomagnetic survey was conducted to study the characteristics of major geological tectonic belts in the northeastern Taiwan. According to this magnetic inference, the basement of igneous rocks older than the continental shelf, Mesozoic or older is very much undulating. Geomagnetic and geological data show that a Pleistocene intrusive rock and volcanic rock outcrops extend from the northern part of Taiwan along the margins of the continental shelf to the islands of the Diaoyu Islands, forming the southern section of the Taiwan-Rex fold zone. This Pleistocene intrusive rock was able to confirm the era of the fold in the Neogene and Tertiary sediments of the real fold belt in Taiwan. Magnetic field data indicate that the volcanic inner arc of Ryukyu is located on the center of the Okinawa Trough near Taiwan. Obviously, it is continuous with the northern arc section of Quaternary volcano. This volcanism is thought to represent the initial stage of the formation of the marginal sea. The calm and low amplitude negative anomalies and the remanent magnetic field contours coincide with the topographic features, indicating that the main ridge of the Ryukyu Island arc is very close to Taiwan. Ryukyu Island arcs that curve northward and residual magnetic field contours that correlate between east longitudes 122 ° and 123 ° are interpreted as a result of a horizontal fault at the main fault.