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介绍了近年来天然地震体波和面波层析成像以及接收函数在怀俄明克拉通地区的应用。怀俄明克拉通地区的地壳和上地幔结构可以归结为克拉通成型时期的残存高速度异常以及进行中Yellowstone低速地幔柱。在克拉通南部边界缝合带地区以及在中部和北部下地壳中保存着一些高速度结构。南部边界缝合带地区的高速度倾斜上地幔结构与人工地震剖面LithoProbe在北美各个克拉通边界所记录的上地幔倾斜反射体一致。作为一个可能的上地幔消减板块残留体,这个倾斜上地幔结构显示出板块叠加可能是一个普遍的克拉通成型过程。在克拉通缝合带的莫霍面和上地幔深度,人工地震的研究结果显示板块叠加过程形成一个楔形体,体现出克拉通上地幔的较高粘度系数。接收函数的转换波共转换点叠加技术显示出这种楔形体存在于整个怀俄明克拉通的南部边界。接收函数和基于噪声的瑞利波层析成像图像显示出在克拉通地壳增厚地区存在下地壳高速体。作为早期岩石圈分裂过程残留的火成岩侵入体,这种下地壳高速体存在于较早成型的克拉通北部和中部地区,显示出南部克拉通地区不同的形成机制。克拉通的西部地区受到Yellowstone地幔柱的影响。层析成像显示低速的地幔柱从黄石地区向下延伸到至少500km。在消蚀岩石圈的同时,岩浆侵入体沿着hotspottrack在中地壳大量的形成,并引起下地壳岩石的横向流动。
The applications of natural seismic bulk wave and surface wave tomography and receiver functions in the Wyoming cratonic region are introduced. The crust and upper mantle structure in the Wyoming Cratons region can be attributed to the remnant high-velocity anomalies during the cratonic formations and the ongoing Yellowstone low-velocity mantle plume. Some high-speed structures are preserved in the southern suture zone of the craton and in the central and northern lower crust. The high-velocity tilted upper mantle structure in the southern boundary suture zone is consistent with the upper mantle tilt reflectors recorded by LithoProbe at each Craton boundary in North America. As a possible remnant of the upper mantle abatement plate, this tilted upper mantle structure shows that plate stacking may be a common cratonic forming process. Based on the Moho and upper mantle depths in the craton, the results of artificial earthquakes show that the plate superposition forms a wedge, which reflects the higher viscosity coefficient of the craton upper mantle. The converted wave co-conversion point stacking technique of the receiver function shows that such wedges exist throughout the southern boundary of Wyoming Cratun. The receiver function and noise-based Rayleigh-wave tomography images show the presence of lower crustal high-velocity bodies in the cratonic thickened area. As a remnant of igneous intrusions in the early lithosphere rifting, this lower crustal high-velocity body exists in the northern and central craton of earlier formations, indicating different formation mechanisms in the southern craton. The western part of Cratun is influenced by the Yellowstone mantle plume. Tomography shows that the low-velocity mantle plume extends downward from Yellowstone to at least 500 km. At the same time that the lithosphere was eroded, the magma intrusions were massively formed along the hotspottrack in the middle crust and caused the lateral flow of rocks in the lower crust.