Reservoir connectivity in deep-water turbidite deposits over geological and production time scales: an integrated study of the Shwe field, Bay of Bengal

Understanding reservoir connectivity is important not only for subsurface interpretation but also for optimizing field development plans. Especially in offshore areas where comparable references or data are lacking, the impact of reservoir connectivity on development plans is directly linked to the project's commercial feasibility. This study investigates the reservoir connectivity of the Shwe field, comprising Late Pliocene deepwater turbidites in the northeastern Bay of Bengal, through a comparative analysis of production results and pre-production connectivity assessments. The exploration findings for the Shwe field led to the interpretation of horizontal and vertical compartments from lobe elements and multiple gas–water contacts. However, ten years of production data reveal significant lateral and vertical dynamic connectivity. From a geological perspective, the results indicate that: (1) multiple water intercepts at a single gas gradient imply the presence of a connected reservoir with non-producible perched waters; (2) compensational stacking leads to extensive overlaps between lobe element layers, enhancing lateral reservoir connectivity through a high net-to-gross ratio (avg. 82%; max. 100%) and multiple amalgamated sand-sand contacts; and (3) sand injectites act as conduits between vertically separated reservoirs, contributing to gas production. This study demonstrates that favorable dynamic connectivity in deepwater turbidite reservoirs can be recognized even in the absence of production data by the aforementioned three characteristics. These results have implications for understanding reservoir connectivity and will help to maximize production efficiency and commercialization through optimizing well recommendations and the development plan.