摘要
在温度为200°—700℃,围压为200—700MPa,恒定应变速率(1×10^(-4)/s)条件下,笔者对长石砂岩和石英砂岩完整的和带预切口的试样进行了变形实验。应力-应变曲线表明,完整砂岩发生了脆性的、脆延性过渡状态的和延性的变形;而带预切口的砂岩在整个实验条件下都发生了稳定摩擦滑动。显微观测表明,岩石变形的主要机制是晶内和穿晶微裂隙的产生和发展。根据实验结果笔者推测,砂岩组成的地壳在地下10km左右的深度有最大破坏强度和摩擦强度;而发育在岩石中的断层的活动一般以稳定摩擦滑动为主。
Under the conditions of temperature 200-700℃, confining pressure 200-700 MPa and constant strain rate (1× 10-4/s) the authors made deformation experiments on samples of feldspar sandstone and quartz sandstone with and without sawcut. The stress-strain curves obtained show that brittle failure, deformation in brittle-ductile transition regime and plastic flow occur in the intact samples under different conditions, while in the sawcut samples stable frictional sliding occurs under the whole range of the experimental conditions. Micro-scopic observation shows that the main deformation mechanism is intra-and inter granular mi-crocracking. Based on the experimental results, the authors here suggest that the crust com-posed of sandstone possesses the maximum failure strength and frictional strength at the depth of about 10 km, and that fault activities in sandstone are dominantly characterized by stable frictional sliding.
出处
《地震》
CSCD
北大核心
1989年第5期50-58,共9页
Earthquake
