The tight sandstone gas reservoir in Ordos Basin is characterized by “thin reservoir, low porosity, low permeability, low pressure, low abundance and strong heterogeneity”, together with low single well production, rapid pressure drop, facing the problems such as stable production and development. In order to develop geological reserves efficiently, horizontal well is widely used in this area. The characteristics of tight sandstone gas reservoir determine that fracturing is the inevitable choice for its economic development. In the past, the fracturing schemes were only determined by “one hole view”, which was lack of deep understanding of reservoir in the area surrounding boreholes. Therefore fracturing schemes were insufficient and economical enough. In order to solve the problems above, a set of seismic methods has been created. Firstly the method of multidimensional analysis of rock physics is used to optimize the geophysical parameters that are sensitive to the gas bearing property of the reservoir. Secondly pre-stack gather data with high quality are obtained by using the processing technology of the relative amplitude of the wide azimuth and the OVT (offset vector slice). Thirdly the spatial distribution of the reservoir is predicted by using the pre-stack elastic inversion. And Combined with the three-dimensional visualization technology, the reservoir distribution of surrounding area of the borehole is determined, which will guide the optimization of fracturing location and direction and scale, so as to perfect the fracturing reconstruction scheme. The set of methods has obtained a good result in Shaan* block of Sulige gas field in China. 44 horizontal wells have been tested achieving a great success. Among them, the AFO of 6 horizontal wells of G* well cluster is over one million m3, making the highest record in the horizontal well development history! So this set of seismic technology is an effective way to optimize the fracturing scheme of horizontal well in tight sandstone gas reservoir.
Presentation Date: Tuesday, October 13, 2020
Session Start Time: 8:30 AM
Presentation Time: 11:00 AM
Location: 362D
Presentation Type: Oral
