역 VSP를 이용한 천부지층 구조연구

A Study on the Shallow Subsurface Structure using an Inverse VSP Method

  An inverse vertical seismic profiling(Inverse VSP) was conducted on the site which consists mainly of 3 layes: thick alluvium layer on the top and weathered rock in the middle, and bed rock at the bottom. The technique uses a split spoon sampler as a downhole source and 24-channel geophone array as receiver. The filed data is compared with the synthetic seismogram in order to decide precise depth of reflections and interval velocity of each layer. The filed data is also compared with the borehole log to confirm accuracy of seismic data interpretation. From both comparison it can be concluded that if the site to be investigated consists of thick alluvium on the top, an inverse VSP technique offers precise depth determination of the bed rock.