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通常划分出两种过渡带,现补充第三种,叫做哥伦比亚型。已证实,所有过渡帶特有的地壳坳陷作用均与大陆型地壳先变为过渡型地壳随后变为大洋型地壳(据地球物理特性)有关。这些变化最可能的机制是:陆壳基性岩化,即陆壳下沉(一块接一块)到热的上地幔中而代之以新洋壳。在太平洋型过渡带的发育过程中起重大作用的是达到地幔未衰歇层的深断裂,在岛弧上形成钙-碱性岩浆所必需的挥发物就是从地幔未衰歇层上升到地表的。贝尼奥夫带是一些深断裂,它们的倾斜是后来形成的,这与贝尼奥夫带两侧的上地幔密度差有关。密度较大的地幔在密度较小的地幔之下,然而不存在板块构造学所描述的那种俯冲现象。虽然在太平洋型过渡带Ⅱ型岛弧中的洋壳由于安山质火山岩层的变厚而增厚,但是,总的说来,过渡带是由大陆朝大洋扩张方向发育的。
Usually divided into two transitional zones, now add a third, called the Colombian type. It has been confirmed that all the crustal depressions unique to the transitional zone are related to the fact that the continental crust first changed into a transitional crust and then into an oceanic crust (according to the geophysical characteristics). The most likely mechanism for these changes is the continental crustal lithification, where the continental crust sinks (one after the other) into the hot upper mantle and replaces it with a new oceanic crust. In the development of the Pacific transition zone, it plays a major role in reaching deep ruptures of the non-decay layer of the mantle. The volatiles necessary for the formation of calcium-alkaline magma on the island arc are those that rise from the non-decay layer of the mantle to the surface . The Benioff belts are deep faults, and their tilts are formed later, which is related to the density difference of the upper mantle on both sides of the Benioff belt. The denser mantle beneath the less dense mantle, however, does not have the subduction phenomena described by plate tectonics. Although the oceanic crust in type II island arc in the Pacific transition zone is thickened by the thickening of the andesite volcanic rocks, in general the transitional zone develops from the continent towards the oceanic expansion.