Detecting and Managing Inter-Reservoir Communication between Two Stacked Reservoirs

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractThe challenge of how to effectively manage a field with multiple reservoirs that are in hydraulic communication comes up routinely when the field is under waterflood. Conventional management of such fields can result in many undesired outcomes such as a premature water production caused by cross-channeling from different reservoirs, inefficient pressure support to some of the individual reservoirs, or large volumes of bypassed oil. The main challenge that leads to such outcomes is the ability to identify the medium and magnitude of the inter-reservoir communication within the field. This paper addresses a field practice to pinpoint the communication between two reservoirs while the field is on production, along with its capability to further improve the effective reservoir management.The field consists of two large carbonate reservoirs separated by thick non-reservoir formation. Historical data proved the inter-reservoir communication in the field. I-Field technology was a primary component in the development of this field. This technology has become a tool for an effective day-to-day reservoir management. This enables pro-active management rather than the traditional, re-active, management with respect to field life due to its added advantage of early detection of anomalies and subsequently enhances characterization. In this field, i-field facilitated a field-wide interference test that was conducted prior to field production start-up to help with field characterization including inter-reservoir communication between the two reservoirs.Field cases describing the integration of static and dynamic data that led to better understanding of the field are presented. Results of this study will play a major role in building a robust dynamic model that can capture the fluids exchange between the two reservoirs. Such model will become an important tool for managing both reservoirs in order to maximize ultimate recovery from the field.