论文部分内容阅读
记录常规垂直地震剖面数据时,都要等深度间隔地移动检波器。由于地层速度的变化,所得到的是不固定时间增量的垂直地震剖面。如果事先知道了层速度,则根据这些层速度值在不同深度点上移动检波器,便可以得到固定时间增量的垂直地震剖面资料。对于水平层次来说,固定时间增量的垂直地震剖面上的全部上行波有一个共同的斜坡,全部下行波也有一个共同的斜坡。在空间上经过重新采样,可以把正常的固定深度增量的垂直地震剖面变成固定时间增量的垂直地震剖面。这种方法与反射地震学中深度-时间转换法相类似。另外,向上延拓上行波和下行波,就可以模拟出地表与最浅处的检波器之间没有记录到的资料。由深度增量向时间增量转换,要利用上行波和下行波的某些特征。分析到达检波器的直达波和垂直地震剖面的几何图形,能够得到振幅校正中的一些参数。波的延拓与内插,主要依赖于下列事实,即到达地表的初次反射能够产生下行波。这意味着,只要知道其一,便可知其二。由于下行波是上行波的一种延拓,那么将下行波的极性反转并进行振幅校正,再加上时间对称性,便可得到上至地表的上行波。内插和波的向下延拓也基于同一道理。全部原始道都是包括在固定时间增量的垂直地震剖面资料中的。固定时间增量剖面的优点包括:延伸了空间边界,降低了边界效应,消除了空间假频,简化了分离上行波和下行波的过程,以及深入地解释了初次波和多次波之间的关系。
When recording normal vertical seismic section data, move the geophones equally deeply. Due to the variation of the formation velocity, the vertical seismic profile obtained by the unsteady time increment is obtained. If the layer velocity is known in advance, the vertical seismic section data of a fixed time increment can be obtained by moving the detector at different depth points according to the layer velocity values. For the horizontal level, all the upgoing waves in the vertical seismic section with constant time increment have a common slope, and all the descending waves also have a common slope. After resampling in space, the normal vertical seismic section at fixed depth increments can be turned into a vertical seismic section with fixed time increments. This method is similar to reflection-seismology depth-time transformation. In addition, upward upward and downward wave extension up, you can simulate the surface and the shallowest detector did not record the data between. From incremental to incremental incremental time to take advantage of some of the characteristics of the uplink and downlink waves. Analyzing the geometry of the direct wave and vertical seismic sections that arrive at the geophone, some of the parameters in the amplitude correction can be obtained. The continuation and interpolation of waves depend mainly on the fact that the first reflections reaching the Earth’s surface can produce a descending wave. This means that as long as you know one, we can see the second. Since the descending wave is an extension of the ascending wave, the polarity of the descending wave is inverted and amplitude corrected, plus the time symmetry, the upgoing wave up to the surface can be obtained. Interpolation and wave down the extension is also based on the same token. All of the original tracks are included in the vertical seismic section data at fixed time increments. The advantages of a fixed-time incremental profile include extending the boundary of the space, reducing the boundary effect, eliminating spatial aliasing, simplifying the process of separating the upgoing and descending waves, and in-depth interpretation of the relationship between the primary and the multiple relationship.