【摘要】 软沉积物滑塌变形是一种地质现象,对于分析区域地质发展史和指导油气勘探具有重要的意义,近年来越来越受到地学界的重视。但大多数的研究是基于野外现象的定性观察描述,对其形成过程和成因机制的定量探究较少。笔者建立了一套斜坡背景下重力驱动的软沉积物滑塌变形物理模拟实验装置,并设计了完整的实验程序,利用具有不同黏滞系数的材料模拟地层,通过多次实验改变沉积箱坡度模拟不同的地层倾角,总结了软沉积物滑塌变形的演化模式:滑塌开始,模拟地层逐渐隆起;随着地形坡度变大,滑塌褶皱依次发展成圆弧褶皱、紧密等斜褶皱,断裂产生后形成类似无根等斜褶皱和鞘褶皱的变形构造,直到地层趋于平稳。分析了软沉积物滑塌变形的机理:软沉积物受到自身沿斜坡重力的驱动,发生滑塌,层与层之间的剪切效应导致软沉积物发生变形。更多还原

【Abstract】 Soft-sediment slump deformation is a geological phenomenon,which is significant in analyzing regional geology history and directing petroleum prospecting. So it became valued by scholars in geoscience rapidly in recent years. However,most studies are qualitative descriptions based on observations in the field,and the process of deformation and genetic mechanism were less. A set of simulation device and the complete experimental program has been designed to simulate soft-sediment slump deformation driven by gravity under the background of slope. The materials with different viscosity to simulate strata were used in the experiment,and the angle of the box was changed to simulate the angle variation of the stratum many times. Then the evolution model of soft-sediment slump deformation were summarized:At the beginning of the deformation,stratum upheaval occurred gradually; as the slope become steeper, in turn,slump folds develop into round-hinged folds and then tight isoclinal folds. After faults formed,folds develop into deformation like rootless isoclinal folds and sheath folds,and the deformation continues till strata come to be stable. The deformation mechanism of the soft-sediment slump deformation was analyzed:Driven by gravity soft-sediments slide down along the slope,and the deformation was caused by the shear effect between layers.更多还原