Abstract:In order to reduce cable wave and ensure repeatable shooting in vertical seismic profile survey, we use the following field method: electric sparker fires repeatedly with different energy levels at a depth of 5m below water table in a shot hole, well geophones are kept in close contact with hole wall, geophone interval is 20-50m and the cable is relaxed while shooting. The key to data processing lies in accurate time corrections which are computed from velocity model made by well shooting data, After the time corrections are applied to the time measurements of corresponding VSP traces, a zero-offset time section similar to that got in surface seismic survey is obtained, Finally,2D filtering is used to eliminate low velocity cable wave and tube wave. Seismic frequency-depth curve can be plotted from VSP data. This curve is then used to estimate absorption coefficients.VSP data can also be used in studies of HCI, geologic structures and lithology nearby a bore hole.
引用本文:
荆大威. 垂直地震剖面的采集、处理与应用[J]. 石油地球物理勘探, 1984, 19(4): 329-334.
Jing Dawei. The caquisition, processing and application of VSP data. OGP, 1984, 19(4): 329-334.