In this work, we calculate the gravity signature of small density changes in a real-case deep reservoir. Based on the 3D forward density modeling of constrained geometries and using parameters of the involved rocks and fluids, we compute the differential gravity signature before and after the production period of the Volve oil field in the North Sea. Causative sources of the retrieved residuals are spatially correlated with positions of the most productive wells, locating areas of maximum density change. Results show that the 4D gravity forward model is capable of resolving residual gravity signatures also for deep and small density changes. In particular, we locate ∼−13 μGal gravity minima over the 2750 m deep reservoir; this minima was caused by the −53 kg m^–3 density change related to production and injection activity.

在这项工作中，我们计算了在实际情况下的深层储层中小密度变化的重力特征。基于约束几何的3D正向密度建模并使用所涉及的岩石和流体的参数，我们计算了北海Volve油田生产期间前后的重力差特征。所取残差的致因源与生产力最高的井的位置在空间上相关，位于最大密度变化的区域。结果表明，4D重力正向模型也能够解决残余重力特征，包括深度和较小的密度变化。特别地，我们找到〜−13μ2750 m深水库上方的Gal重力最小值；此最小值是由与生产和注入活动有关的−53 kg m ^–3密度变化引起的。