Optimization of Upper Burgan Reservoir Multilateral Well With Inflow-Control Device

Abstract

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 175227, “Optimize Development Strategy of Upper Burgan Reservoir Through Multilateral Well With Inflow-Control Device in Raudhatain Field, North Kuwait,” by Sankar Chowdhuri, Peter Cameron, Tarek A. Gawwad, Mohammad R. Madar, Siddhartha Sankar Sharma, Moute’a Dughaim AlMutairi, Vijay Shankar Rajagopalan, Suresh Chellappan, and Moudi Fahad Al-Ajmi, Kuwait Oil Company, prepared for the 2015 SPE Kuwait Oil & Gas Show and Conference, Mishref, Kuwait, 11–14 October. The paper has not been peer reviewed. In coning situations, such as in the production of oil reservoirs with a bottom aquifer, multilateral wells reduce the coning effect and, hence, prove to be more cost-effective. This paper discusses the first multilateral well with a Level-4 junction combined with an inflow-control device (ICD) planned, designed, and drilled in the Upper Burgan reservoir of Raudhatain field, north Kuwait. The paper covers the main challenges of well placement during geosteering to ensure the best quality of reservoir rock in structurally and depositionally complex settings with smart-completion design. Introduction The Raudhatain oilfield structure is one of several developed along a prominent anticlinal ridge that plunges gently north of Kuwait. These individual highs, in which the principal oil accumulations of the area are localized, tend to be of large areal extent and substantial structural relief. The Raudhatain structure exhibits a quasiradial pattern of small normal faults of limited throw. This geometry suggests a primary origin by uplift. The Raudhatain structure is a faulted anticlinal dome with 65 to 90 ft of topographical relief. The 3D seismic has defined the major faulting in the northern part of Raudhatain as northwest trending, whereas in the southwestern part of the field the faults trend northwest. Fault throws are highly variable and range from less than 30 ft to as much as 150 ft. Stratigraphy of Upper Burgan Reservoir The Burgan formation is a major reservoir unit. It unconformably overlies the carbonate Shuaiba formation and underlies the Mauddud carbonates with locally unconformable contact. The thickness of Burgan is approximately 950 ft of soft, clean, porous, well-sorted quartz sandstones of littoral to possibly deltaic aspect, interbedded with siltstones and dark shales. The Burgan formation at Raudhatain has been divided informally into three members, termed the Upper Sand, Middle Shale, and Lower Sand.