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Multi-component seismic exploration is an important technique in the utilization of P-waves and converted S-waves for oil and gas exploration. It has unique advantages in the structural imaging of gas zones, reservoir prediction, lithology, and gas-water identification, and the development direction and degree of fractures. Multi-component joint inversion is one of the most important steps in multi-component exploration. In this paper, starting from the basic principle of multi-component joint inversion, the differences between the method and single P-wave inversion are introduced. Next, the technique is applied to the PLN area of the Sichuan Basin, and the P-wave impedance, S-wave impedance, and density are obtained based on multi-component joint inversion. Through the velocity and lithology, porosity, and gas saturation fitting formulas, prediction results are calculated, and the results are analyzed. Finally, multi-component joint inversion and single P-wave inversion are compared in effective reservoir prediction. The results show that multi-component joint inversion increases the constraints on the inversion conditions, reduces the multi-solution of a single P-wave inversion, and is more objective and reliable for the identification of reservoirs, effectively improving the accuracy of oil and gas reservoir prediction and development. [ABSTRACT FROM AUTHOR]

Presented a study on shale gas reservoir of Longmaxi Formation of Lower Silurian in southern Sichuan Basin. The reservoir porosity was measured using nitrogen adsorption method. The pore volume, pore specific surface area and pore size distribution were studied through the isotherms and DFF analysis. Based on all of these, discussed the main factors to control the nanopore structure and the nanopore's influence on shale gas accumulation. The results show that, the pore structure of the shale gas reservoir of Longmaxi Formation is relatively complex, which is composed of nanopores and possesses a certain ruleless structure (the amorphous pore), pores are open in style and mainly consist of the cylinder pores with two ends open and parallel-plate pores with four sides open. It is concluded that openness degree of the pores improved with the increase of the vertical depth, the sizes of the main nanopores are in a range of 2 ~40 nm, which take up 88.39% of the total volume of pores and 98.85% of specific surface area. Most of the pore volume is occupied by the mesopores which are 2 ~ 50 nm in size. The micropores and mesopores of which the diameters are less than 50 nm dominate the main pore specific surface. The main internal factor to control the volume and the pore specific surface of nanopores of the shale gas reservoir in Longmaxi Formation is TOC content. It is also the important substance to provide the main storage space. The nanopores have a strong ability to absorb shale gas, the interior of which is structured filled with the shale gas, thus increase shale gas storage capacity and finally make the model characteristic complicated. The open nanopores can improve the shale gas desorbing efficiency and the permeability of the reservoirs, and then improve the shale gas production. [ABSTRACT FROM AUTHOR]