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白令海内存在着三个海下高地:希尔索夫海岭,鲍尔斯海岭和乌姆纳克高地。在乌姆纳克高地的折射资料和以前的穿过鲍尔斯海岭的地球物理资料表明,这两个地貌单元为增厚的地壳物质边界。地壳结构为大洋型和大陆型之间的过渡型。对于这些地貌单元的成因已讨论过各种模式。先前未曾提出过的一种模式认为,鲍尔斯海岭和乌姆纳克高地的原始构造位置应在现代白令海的外侧。根据此模式,在阿留申海岭形成前的晚中生代或第三纪最早期,这些原始构造运移到了现代的白令海位置内。在这两个构造到达白令海之前, 洋壳曾沿连结阿拉斯加和西伯利亚的白令海陆缘俯冲。原始的乌姆纳克构造高地与这个陆缘的东南段相碰可能造成了俯冲作用在该陆缘终止,並向南转移。因此在阿留申海岭下新形成的俯冲作用是受乌姆纳克高地、鲍尔斯海岭,可能还受西侧的希索夫海岭在晚中生代或早第三纪时的位置所制约。
Three subterranean highlands exist in the Bering Sea: the Hillsborough Ridge, Bowers Ridge, and the Umnak Highlands. The refraction data in the Umnak highlands and the previous geophysical data that passed through the Bowers Ridge indicate that the two geomorphic units are thickened crustal material boundaries. The crustal structure is a transitional type between the oceanic and continental types. Various models have been discussed for the genesis of these geomorphic units. One model not previously proposed suggests that the original tectonic positions of the Bowles Ridge and the Umnak Highlands should lie outside the modern Bering Sea. According to this model, these primitive tectonics moved to the modern Bering Sea location during the Late Mesozoic or Tertiary before the Aleutian Ridge was formed. Before the two structures reached the Bering Sea, the oceanic crust had subducted along the Bering Sea continental margin connecting Alaska and Siberia. The collision of the original Umnak tectonic plateau with the southeastern segment of this continental margin may have caused the subduction to terminate at this continental margin and move southward. Therefore, the newly formed subduction beneath the Aleutian Ridge is controlled by the Umnak Plateau, the Bowers Ridge, and may also be constrained by the location of the Xihetov Ridge in the late Mesozoic or Early Tertiary.