论文部分内容阅读
本文选取地壳地幔中的主要矿物,利用位错蠕变模型和实验数据,通过计算得到了各矿物应力积累的截止温度,从矿物蠕变的角度分析了地壳地幔不同区域应力积累的可能性。结果表明上地壳的高应力环境主要是因为其较低的温度和石英相对较高的应力积累截止温度。辉石的高应变率可能是下地壳应力积累较弱的原因。在地幔中,当深度超过100km以后,地幔温度高于主要组成矿物应力积累的截止温度,使得地幔不大可能产生应力积累。在俯冲带,由于温度较低,一直到瓦兹利石和林伍德石占主要地位的过渡地幔都可能产生应力积累,但是当相变为钙钛矿后,即使在俯冲带也很难具备应力积累条件。
In this paper, we select the main minerals in the crust and use the dislocation creep model and experimental data to calculate the cut-off temperature of each mineral stress accumulation, and analyze the possibility of stress accumulation in different regions of the crust and mantle from the perspective of mineral creep. The results show that the high stress environment of the upper crust is mainly due to its lower temperature and the relatively higher stress accumulation cut-off temperature of quartz. The high strain rate of pyroxenes may be responsible for the weaker accumulation of stress in the lower crust. In the mantle, when the depth exceeds 100 km, the temperature of the mantle is higher than the cut-off temperature at which the major component mineral accumulates, making the mantle less likely to accumulate stress. In the subduction zone, stress build-up may occur due to lower temperatures until the transitional mantle, where the Valence and Lyndhurst dominate, but it is difficult to have stress accumulation even in the subduction zone after transformation to perovskite condition.