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利用新近完成的粘弹塑构造模拟软件包对盆地的动力学演化进行了一系列模拟。文中主要概述不同厚度的上地壳中由高角度平面正断层界定的半地堑盆地的演化模拟。模拟时上地壳被考虑成具有Byerlee型强度包络 ,并且位于无粘性基底之上 ,盆地中由密度比地壳密度小的沉积物充填。计算了以一定增量逐渐拉伸上地壳层时各个阶段的非静岩应力 (Nonlitho staticstress)、塑性破裂 (Plasticfailure)分布及挠曲剖面 (Flexureprofile)。塑性变形使得有效弹性厚度减小。到切穿破裂出现以前 ,断层断距一直增加 ,之后 ,断距基本停止增加。所以 ,地壳强度使沉降量和隆升量均有极限。上地壳层厚度和沉积物密度是控制盆地宽度和极限深度的两个重要因素 ,上地壳层厚度增加或者沉积物密度加大都使盆地宽度和深度增大。模拟结果可以解释一些大陆裂谷盆地的宽度和沉积深度。
A series of simulations have been carried out on the dynamic evolution of the basin using the recently completed viscoelastic modeling package. In this paper, the evolution of semi-graved basins defined by high-angle planar normal faults of different thicknesses in the upper crust is mainly summarized. The upper crust was modeled as a Byerlee-type intensity envelope and above the non-sticky substrate, where the basin was filled with sediments with lower density than the crust. The Nonlitho staticstress, Plasticfailure distribution and Flexure profile of each stage when the upper crust is gradually stretched by a certain increment are calculated. Plastic deformation reduces the effective elastic thickness. Until the cut-through rupture occurs, the fault breakage has been increasing. After that, the breakage has basically stopped increasing. Therefore, crustal strength has both limits of settlement and uplift. Upper crustal thickness and sediment density are two important factors that control the width and depth of the basin. The increase of the thickness of the upper crust or the increase of sediment density will increase the width and depth of the basin. The simulation results can explain the width and depth of sedimentation in some continental rift basins.