The application of VR technology in E&P of low-permeability gas reservoir in northeastern Ordos basin

The priority of exploration was to search for high porosity zones because the reservoirs are thin, tight, low porosity, low permeability, and heterogeneous. By taking advantage of virtual reality (VR) technology, this paper presented a method called seismic attributes over reflection structure. Firstly, based on an analysis of drilling, logging, geologic and geophysical data, a forecast pattern of the development of high porosity zone was established for determination of relatively thick channel sand. Secondly, 3-D seismic data volume was browsed by VR techniques. As a result, it was found that channel deposits were of discontinuous lenticular reflection configuration. Finally, 3-D carving was implemented over channel sands on seismic attribute volume to delineate the spatial extents of the sands and highlight their configurations in vertical and horizontal directions. 9 well positions were recommended based on the predicted results. All of the 7 drilled wells encountered the targets, and produced commercial gas flow. The average gas production amounts to 169, 000 cubic metre, which is ten times higher than that of the previous production wells, and the highest production reaches as high as 589, 000 cubic metre per day.