Abstract: To address the problem that the energy deficit of the old well formation has an impact on the reservoir stimulation and production of the new well, a numerical model of the reservoir is established on the basis of a three-dimensional geological and ground stress model, the dynamic change law of the stress field of the old well is studied in combination with the production data, the characteristics of the fracture pattern of the new well are predicted based on the fracture propagation model, and the fracturing design parameters are optimized. The study shows that the ground stress area caused by the development of old wells has an induced effect on the fracture propagation of neighboring wells, and optimizing the ratio of the front fluid in new wells can compensate for the formation energy deficit, avoid the artificial fracture in new wells from extending excessively in the deficit direction, so that the reservoir stimulation is more adequate and post-fracturing capacity is more desirable. The example application of Well Group H1 in the Mahu conglomerate reservoir shows that the preferred cluster spacing is 25-30 m, the fluid intensity used is 18 m³/m, and the single cluster pad fluid volume is 400 m³, which can effectively inhibit the induction of artificial fractures in new wells by low stress zones and improve the proppant placement concentration. This study has important guidance for the development of similar conglomerate reservoirs.

Key words: dynamic ground stress field, formation deficit, inter-well interference, fracturing optimization, tight reservoir