Department of Geosciences, Princeton University, Princeton, NJ, USA.
Science. 2013 Aug 23;341(6148):871-5. doi: 10.1126/science.1241335. Epub 2013 Aug 8.
We constructed a three-dimensional azimuthally anisotropic model of Europe and the North Atlantic Ocean based on adjoint seismic tomography. Several features are well correlated with historical tectonic events in this region, such as extension along the North Atlantic Ridge, trench retreat in the Mediterranean, and counterclockwise rotation of the Anatolian Plate. Beneath northeastern Europe, the direction of the fast anisotropic axis follows trends of ancient rift systems older than 350 million years, suggesting "frozen-in" anisotropy related to the formation of the craton. Local anisotropic strength profiles identify the brittle-ductile transitions in lithospheric strength. In continental regions, these profiles also identify the lower crust, characterized by ductile flow. The observed anisotropic fabric is generally consistent with the current surface strain rate measured by geodetic surveys.
我们基于伴随地震层析成像构建了一个欧洲和北大西洋的三维方位各向异性模型。该模型中存在多个特征与该地区的历史构造事件密切相关,如北大西洋洋脊的扩张、地中海海沟的后退以及安纳托利亚板块的逆时针旋转。在东欧下方,快各向异性轴的方向与 3.5 亿年前的古老裂谷系统的趋势一致,这表明与克拉通形成有关的“冻结”各向异性。局部各向异性强度剖面确定了岩石圈强度的脆-韧性转变。在大陆地区,这些剖面还可以识别出具有韧性流特征的下地壳。观测到的各向异性构造与大地测量调查测量的当前地表应变速率基本一致。