A new interpretation model utilizing the combination with acoustic-resistivity-NMR for gas reservoir identification in tight sandstone

摘要

Aiming at gas reservoir identification in tight sandstone formations, this paper proposes a new method based on acoustic-resistivity-NMR multi-parameter identification of gas. In this paper, the pore structure is used as a link to relate the acoustic velocity, NMR relaxation time and resistivity. Combining with numerical simulation and rock physics experiments, the relationship between acoustic time difference, resistivity and T2 is established. Based on these theoretical and experimental measurements, we have developed an interpretation model that combines resistivity-T2 and DTC. Compared with the traditional model of the combination of Vp/Vs and DTC, the gas can be clearly distinguished by this new model. Finally, we used the core data of the G4 well to verify the feasibility of the new interpretation model.