INDICATION OF FORMATION WATER ON TIGHT OIL AND GAS ACCUMULATION MODEL IN CHINA

As an important carrier of oil and gas, the genetic type, chemical composition, hydrodynamic field and spatial distribution characteristics of formation water can reflect the migration and accumulation model of tight oil and gas. However, the current research on the significance of formation water to tight oil and gas accumulation is weak, and the existing research lacks a systematic summary. In this paper, the indication effect of formation water in various petroliferous basins on tight hydrocarbon accumulation in China over the past decade has been systematically summarized. The study found that the indication effect of formation water on hydrocarbon accumulation can be divided into six types, including water chemical accumulation model, strong alternating hydrodynamic accumulation model, fault-induced reservoir formation model, fracture cave system accumulation model, "acid point" deep basin gas accumulation model, and water soluble gas desolvent accumulation model. Different accumulation models have different developmental characteristics, and the same petroliferous basin may have multiple composite accumulation modes. This research has important reference value for guiding the exploration of complex unconventional oil and gas reservoirs worldwide.