Paleotectonic Controls on the Boundary Between Thin and Thick-Skinned Deformation

小行星9418087 褶皱/冲断带表现出两种根本不同的构造样式--有基底的（厚皮）和只有盖层的（薄皮）。 以往的研究表明，厚皮变形和薄皮变形在30 ° S的安第斯山脉同时活动，边界发生在中部前心带和东部前心带（Sierra Pampeanas）之间的几何三角带上。 该项目将使用独特的工业地震反射数据集和实地工作来调查构造几何形状的巨大变化是由阿根廷西部地壳中预先存在的各向异性控制的假设。 研究结果有助于解释褶皱-冲断带厚变形和薄变形的控制机制。

9418087 Allmendinger Two fundamentally different tectonic styles are exhibited by fold/thrust belts- those involving basement (thick-skinned) and those involving only cover (thin skinned). Previous work has shown that thick and thin-skinned deformation are both active simultaneously in the Andes at 30oS, and the boundary occurs across a geometric triangle zone between the central precordillera and the eastern precordillera, Sierra Pampeanas. This project will use a unique industry seismic reflection data set and fieldwork to investigate the hypothesis that the dramatic change of structural geometry is controlled by preexisting anisotropies in the crust of western Argentina. Results should help explain the controls on thick or thin deformation styles in fold-thrust belts.