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过去十年中,在西伯利亚得到的若干条长剖面显示了西伯利亚地台复杂的岩石圈构造。距离可达3000 km的三分量地震观测,使得有可能得到地壳中的P波和S波速度、上地幔的P波速度和Q值以及与反射波、折射波和转换波有关的地震界面,它们的深度可至400—700 km。地壳模型是典型的欧亚古地台模型,平均厚度为40 km,被分为三层,P波速度分别为6.2、6.5、7.0km/s,厚度均为10—15 km。莫霍界面的深度从古老的通古斯凹陷下方的40—50 km至年轻的Vilyui盆地下方变为35—40 km,最复杂的莫霍面结构位于西西伯利亚和西伯利亚地台之间的边界处。上地幔显示了P波速度模型强烈的不均匀性。在深度为80—100 km的上地幔的最上层,水平方向的不均匀性更大,在这里P波速度从年轻的西西伯利亚地台下方的8.0—8.2 km/s至西伯利亚克拉通某些部分的下方变为8.4—8.6 km/s。在对地震记录进行了计算处理以后,利用反射波研究了垂直方向精细的不均匀性。结果勾划出几个厚度为20—50Km的低速层,这些低速层同时还具有低Q值的特点。记录到了来自上地幔和下地幔之间过渡带的强波组。在这个区域,该过渡带的顶部是近乎水平的,其深度是400±25 km,过渡带底部的深度大约为700 km。
Over the past decade, several long profiles obtained in Siberia show the complex lithospheric structures on the Siberian platform. Three-component seismic observations up to 3000 km make it possible to obtain P-wave and S-wave velocities in the crust, P-wave velocities and Q-values of the upper mantle, and seismic interfaces related to reflected, refracted, and converted waves The depth can reach 400-700 km. The crustal model is a typical Eurasian platform model with an average thickness of 40 km and is divided into three layers. The P wave velocities are 6.2, 6.5 and 7.0 km / s respectively, and the thickness is 10-15 km. The depth of the Moho interface changes from 40-50 km below the ancient Tunguska depression to 35-40 km below the young Vilyui basin. The most complex Moho structure is located at the boundary between the West Siberia and Siberian platforms. The upper mantle shows the intense inhomogeneity of the P-wave velocity model. At the uppermost layer of the upper mantle at a depth of 80-100 km, horizontal inhomogeneities are greater where P-wave velocities range from 8.0-8.2 km / s beneath the young West Siberian platform to some parts of the Siberian craton The bottom becomes 8.4-8.6 km / s. After the seismic records have been calculated and processed, the vertical inhomogeneities have been studied using reflected waves. The result delineates several low-velocity layers with a thickness of 20-50 km. These low-velocity layers also have a low Q-value. The strong wave group from the transition zone between the upper and lower mantle was recorded. In this region, the top of the transition zone is nearly horizontal with a depth of 400 ± 25 km and a depth of about 700 km at the bottom of the transition zone.