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对汶川地震断裂带深溪沟出露的基岩错动面两侧岩脉中的石英矿物进行了拉曼谱峰测定,并根据所测石英的464cm-1拉曼谱峰向高波数的偏移量估算了断裂带中的压应力分布。测试结果表明,错动面附近岩脉中石英的464cm-1拉曼谱峰向高波数偏移量为3.29cm-1,相应的压应力值为368.63 MPa,明显低于错动面两侧应力积累,这可能是由于错动面的多次活动导致了应力不断得到释放。断裂南东盘(下盘)远离错动面,岩脉中石英的464cm-1拉曼谱峰向高波数偏移量具有增加的趋势,相应的应力积累也逐渐增强,距错动面21m处的石英样品的464cm-1拉曼谱峰向高波数偏移4.40cm-1,相应压应力可达到494.77MPa。剖面北西盘(上盘)在距错动面10m处,样品464cm-1拉曼谱峰的偏移量达到最大值,相应的应力积累为519.87 MPa,其后远离错动面应力积累开始减弱,在北西盘17 m处,应力积累骤然下降至400.37MPa。在西北盘距错动面27m处,岩脉石英的464cm-1拉曼谱峰向高波数偏移量下降至3.21cm-1,应力已经减弱到359.59 MPa,这可能是由于该处位于断裂带的边缘,远离错动面,受到了较小的断层活动的影响。因此,汶川地震断裂带内的应力虽然得到部分释放,但剩余的应力分布并不均匀,而且在局部还存在较高的应力积累,这反应了断裂带中岩石的力学性质在空间上具有不均匀性。
The Raman spectrum of quartz minerals in the dikes on both sides of the bedrock slip surface in Shenxigou Wenchuan earthquake fault zone was measured. According to the Raman peak of the 464cm-1 peak of quartz measured to the high wavenumber The displacement estimates the compressive stress distribution in the fault zone. The results show that the 464cm-1 Raman peak of quartz in the dike near the dislocation surface shifts to a high wave number by 3.29cm-1 and the corresponding compressive stress is 368.63MPa, which is obviously lower than that of both sides of the dislocation surface Accumulation, which may be due to repeated activities of the wrong face caused by the constant release of stress. The south-east plate (bottom plate) of the fault is far away from the misalignment surface. The 464cm-1 Raman peak of quartz in the veins has an increasing tendency toward higher wave numbers and the corresponding stress accumulation gradually increases, The 464cm-1 Raman peak of the quartz sample shifts to a high wave number by 4.40cm-1 and the corresponding compressive stress can reach 494.77MPa. The shift of the 464cm-1 Raman peak at the northwest plate (upper plate) of the sample at a distance of 10m from the moving surface reaches the maximum value, the corresponding stress accumulation is 519.87 MPa, and then the stress accumulation away from the moving surface begins to weaken, At 17 m northwest plate, the stress accumulation suddenly dropped to 400.37 MPa. At 27m of the offset surface of the northwest plateau, the 464cm-1 Raman peak of quartz veins dropped to 3.21cm-1 from the high wave number and the stress had weakened to 359.59MPa, probably due to the location of the 464cm- The edge, away from the misplaced surface, is affected by the smaller fault activity. Therefore, the stress in the Wenchuan earthquake fault zone is partially released, but the residual stress distribution is not uniform, and there is still a high stress accumulation in the local area, which reflects that the mechanical properties of the rocks in the fault zone are spatially uneven Sex.