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利用黏弹塑性有限元分析方法 ,模拟了厚为 1 0km的上地壳 (假定上地壳具有Byerlee型强度包络 )中以逆断层为边界的盆地的演化 ;假定基底无黏性 ,而盆地中充填的沉积物密度比地壳密度小 40 0kg/m3 。随着每次以 0 .2 5km位移增量逐渐挤压地层 ,塑性破裂区扩大 ,直至挤压位移至约 5 .5km时 ,出现了破裂切穿整个地层的现象。当达到这种状态时 ,盆地的沉降减慢 ,最终停止。地层被挤压至位移 5 .5km后形成一个 30km宽、5km深的盆地。整个演化过程中 ,盆地转折线逐渐向断层移动。切穿破裂出现以后 ,地层被继续挤压到位移 8km ,以便观察研究断层两侧的挤压褶皱构造。这些褶皱是从早期轻微的挠曲起伏演化而来的 ,到挤压位移 3km时 ,它们开始明显增强 ,到挤压位移 8km时 ,已经形成非常大的背斜和向斜 ,其幅度从断层向两侧逐渐减小。
The viscoelasto-plastic finite element method is used to simulate the evolution of basins in the upper crust (assuming the Byerlee-type intensity envelopes in the upper crust) with a thickness of 10 km. The basin is assumed to be non-viscous while the basin is filled The sediment density is 40 0 kg / m3 less than the density of the crust. With each gradual squeezing of the formation at 0.52km increments, the plastic fracture zone expands until the crushing displaces to about 5.5km. When this condition is reached, the settlement of the basin slows down and eventually stops. The formation is squeezed to a displacement of 5.5 km to form a 30 km wide and 5 km deep basin. Throughout the evolutionary process, the basin turning line gradually moved toward the fault. After the cut-through rupture occurred, the formation was further squeezed to a displacement of 8 km in order to observe the crustal structure on both sides of the fault. These folds evolved from the early slight flexing and undulation, and they began to increase significantly when the displacement was 3km. When the displacement was 8km, very large anticlines and synclines were formed that ranged from the fault Both sides gradually decrease.