Boundary Characterization of Complex Lithology Developed Oil Reservoirs Based on Dual Well Testing Fusion Technology

Y oilfield is the first sandstone reservoir in Bohai Sea affected by igneous rocks, with complex geological reservoir conditions. After the oilfield is put into development, there are significant differences between the production dynamic characteristics and static understanding of some production wells, and there is uncertainty in the understanding of reservoir boundaries, reflected in the following two aspects: (1) after the production wells are put into operation, the oil production and flow pressure rapidly decrease, and the reservoir boundaries need further analysis; (2) Some well groups have poor injection production efficiency after water injection, and the understanding of reservoir injection production connectivity is unclear, making it impossible to determine whether there is an impermeable boundary between injection and production wells. In response to the above two issues, a new technology of well testing interpretation based on dual well testing fusion combining “pressure well testing to determine radial flow and production well testing to determine boundaries” is innovatively proposed to identify reservoir boundaries. Establish a 1-injection 1-production reservoir model through numerical well testing design techniques. By using numerical well testing design techniques, a 1-injection 1-production reservoir model is established to study the sensitivity of boundary positions and connectivity coefficients between injection and production wells to the characteristics of regularized pressure integral derivative curves. Based on this, an injection production connectivity model pressure integral derivative double logarithmic curve is established to distinguish the connectivity coefficients between injection and production wells and fill the gap in well testing analysis related charts. Based on the above two research results and combined with static geological understanding, the reservoir boundary of Y oilfield was finely characterized, and the dynamic reserve scale of a single well was clarified, providing new ideas for the boundary characterization of similar oilfields.