Haradh-III: Industry's Largest Field Development With Maximum-Reservoir-Contact Wells, Smart-Well Completions, and the iField Concept

Abstract

Summary The development of Haradh-III in the southernmost region of Ghawar represents a major shift in paradigm in terms of the combination of the technologies. The field development combines four main technology features, which include maximum-reservoir-contact (MRC) wells, smart completions, extensive use of real-time geosteering, and iField initiatives. This paper describes the motivation, implementation, and post-production evaluation of this unique field development. In the case of Haradh-III, field development with smart MRC wells delays water encroachment, improves flood-front conformance and recovery, and lowers water production and long-term development and operating costs. Bottomwater encroachment into the wellbore is mitigated as downhole internal control valves (ICVs), as part of the smart completion, are adjusted. This, in turn, lengthens the life of the well, allowing sweep and recovery to take place in the reservoir below the horizontal wellbores with the most effective sweep process: the replacement mechanism by gravity. The objectives of the development are accomplished by use of a reduced number of wells that minimize the accompanying infrastructure, which lowers the capital expenditure while reducing the operating cost by maintaining, on a long-term basis, a low-water-producing system, all in real time and within the iField environment. Introduction Production at the Haradh-III development started in February 2006. The project included a combination of MRC wells, smart completions, geosteering, and the iField concept, which provides real-time access to downhole information. The efficient integration, along with an understanding of the fluid-flow mechanisms in the reservoir, was the key to the success of this project. Haradh field is located at the southernmost portion of the Ghawar complex and covers an area that is 75 km long and is 26 km at its widest section (Fig. 1). The field consists of three subsegments of approximately equivalent reserves, with an aggregate oil initially in place on the order of tens of billions of bbl. Initial production at Haradh-I started in May 1996, followed by Haradh-II and Haradh-III in April 2003 and February 2006, respectively. The field developments, occurring over a span of a decade, offer a unique opportunity to gauge the impact of technologies. Haradh-I was developed by use of vertical wells exclusively, whereas horizontal completions provided the primary configuration for producers/injectors in Haradh-II. Haradh-III, the focus of this paper, was developed by relying mainly on smart MRC completions (Fig. 2) within an iField framework. The total Haradh production capacity is 900,000 B/D, with equal contributions from the three respective subsegments I, II, and III. Key statistics for Haradh-III are shown in Table 1 (Saleri et al. 2006). Geological Setting Geologically, the Arab-D carbonate reservoir is divided into several zones: Zone-1, at the top, is a thin layer separated from the main producing zones by an impermeable nonporous layer of anhydrite. Zone-2A, below Zone-1, is mostly skeletal oolitic limestone with scattered vugs and local superpermeability super-k zones. Below Zone-2A is Zone-2B, which commonly includes dolomite and cladocoropsis-based super-k intervals (Valle et al. 1993) (Fig. 3). Below Zone-2B are Zone-3A and Zone-3B, which have significantly lower reservoir quality. Major and minor faults identified from 3D-seismic data and associated fracture swarms (corridors) have been observed in various degrees throughout the Arab-D reservoir in adjacent regions (Pham et al. 2002). In addition, diffuse fractures are observed to be pervasive in cores (Fig. 4).

Integrated Water Management and Surveillance Strategies in a Giant Carbonate Field from Saudi Arabia

“…This reservoir is heterogeneous in nature where each zone has distinctive reservoir characteristics that can be distinguished from other layers. For instance, the top zone contains mostly skeletal oolitic limestone texture characterized by scattered super-permeable stratform layers and vugs (Al-Kaabi 2008). Figure 1 shows an indication of these features as seen from cores in one of the wells.…”