Active Tectonics, Rate of Convergence, and Earthquake Recurrence in Tien Shan

[304587]这项研究是对中国西部天山省两年构造学研究的延续。研究计划是沿着山脉南缘的褶皱和冲断带的剖面绘制地质图，并构建平衡剖面，估算地壳缩短量。现在几乎所有的数据都在手，可以对该范围的北部边缘进行相同的估计。对天山南侧切割冲积扇的断裂带高度的测量和相关的测年将使我们能够估计全新世时期整个范围边缘的缩短率。地表地质观测到的变形样式将与地震、地震和地质学提供的证据有关。目标包括确定新生代总缩短和晚第四纪缩短速率的界限，将与地震、褶皱和冲断带相关的断裂样式联系起来，并了解大陆内造山是如何发生和发展的。这项研究是国家减少地震危害计划的一个组成部分。＊＊＊

9304587 Molnar This research is a continuation of a two-year study of the tectonics of the Tien Shan province of western China. The research plan is to map geology along a cross section through the fold and thrust belt along the southern margin of the range and construct balanced cross sections to estimate amounts of crustal shortening. Nearly all of the data are now in hand to make the same estimates across the northern margin of the range. Measurement of fault scarp heights that cut alluvial fans on the south side of the Tien Shan and associated dating will allow estimates of shortening rates across the edge of the range in Holocene time. The style of deformation seen in the surface geology will be related to the evidence provided by earthquake seismology and geology. Goals include placing bounds on the total Cenozoic shortening and on the late Quaternary rate of shortening, relating the styles of faulting associated with earthquakes and with the fold and thrust belts, and gaining an understanding of how intracontinental mountain building occurs and develops. This research is a component of the National Earthquake Hazard Reduction Program. ***