Zhang X.,State Key Laboratory of Oil and Gas Reservoir Geology and Development Engineering |
Zhang X.,Chengdu University of Technology |
Chen H.,State Key Laboratory of Oil and Gas Reservoir Geology and Development Engineering |
Chen H.,Chengdu University of Technology |
And 7 more authors.
Oil and Gas Geology | Year: 2013
The 90° phase conversion and slicing techniques are two important seismic sedimentology research approaches. However, tracing and correlation of small-scale isochronal seismic interfaces are challenging in reality, as the 90° phase conversion technique could not correctly reflect the relationship between lithology and seismic responses. The solution to the problem is to use SpecDecomp technology to trace the small-scale isochronal seismic interfaces and then improve seismic resolution with drilling-constrained mix-phase wavelet deconvolution technology while ensuring a rational signal-to-noise ratio. During the process, the seismic section is dephased and geological information is extracted from seismic responses. The new approach had been applied to the study of the 9th sand group of the fourth member of the Xujiahe Formation(T3x4(9)) in Xinchang area of western Sichuan Basin. The result shows that sandbodies are well developed inside the group and are superimposed with one another as the underwater distributary channels moved and shifted frequently. According to the extension direction of the sandbodies, the authors judge that the Longmengshang island group in the north is the provenance. The central Xinchang area contains the thickest sandbody of all as a result of the superimposition of multiple phases of underwater distributary channels. As the compaction resistance of conglomerate can protect the pores of sandstone, the sandbodies in areas with superimposed underwater distributary channels have favorable physical properties, therefore are considered potential exploration targets.
Fu Y.,Southwest Petroleum University |
Du Z.,State Key Laboratory of Oil and Gas Reservoir Geology and Development Engineering
Underground Storage of CO2 and Energy - Proceedings of the Sino-German Conference, and the Sino-German Workshop "Eor and New Drilling Technology | Year: 2010
During running an underground gas storage operation in a depleted fractured oil reservoir, it is observed that the porosity and permeability of this reservoir experiences variation cycles, which is caused by the uncompleted reversible deformation as pressure in reservoir increasing and decreasing alternately. Diffusion of natural gas molecule occurs if there exists a concentration difference between fracture and matrix system. Oil in matrix is inflated by the dissolved natural gas and then flows into the fracture systems, thus oil recovery is enhanced as a result. However, the part of gas dissolved can not be produced. Based on the Warren- Root dual porosity theory, a new mathematical model of underground gas storage is established, in which the effect of uncompleted reversible deformation and molecular diffusion are included. The solution of this numerical model is derived and a computer code is programmed.
Zhang X.-H.,State Key Laboratory of Oil and Gas Reservoir Geology and Development Engineering |
Zhang X.-H.,Chengdu University of Technology |
Lin L.-B.,State Key Laboratory of Oil and Gas Reservoir Geology and Development Engineering |
Lin L.-B.,Chengdu University of Technology |
And 5 more authors.
Natural Gas Geoscience | Year: 2013
Jurassic Ziliujing Formation in the Yuanba region, Northeast Sichuan belongs to fan delta deposition. The fan delta-front underwater distributary channel controls the development of sand body and fracture can improve the physical properties of reservoir, which together control the distribution and development of reservoirs. In view of the complex tectonics, and the difficult comparison between seismic horizon due to the oscillation and migration of riverway, this paper used the seismic horizon comparison based on the seismic frequency division technology, identified the distribution of underwater distributary channel according to the seismic facies and seismic attribute sections. Seismic data with wavelet reconstruction can clearly descript small faults. It finally determined the composite area between underwater distributary channel and fracture development belt as favorable reservoir development zone, which provided a sound basis for the future exploration.