oa Umm-Roos prospect: New Jurassic hydrocarbon play in West Kuwait

Jurassic development activities in western Kuwait are limited to the Minagish, Abduliyah, Dharif and Umm Guddair fields. Until recently, Kra Al Maru was the only Jurassic accumulation outside these fields. Systematic exploration since 2000 has resulted in the Kahlulah and Rahayiah discoveries along the Minagish-Kra Al Maru and Minagish-Rahayiah trends. Significant leads occur as the continuation of good reservoir facies within the Marrat Reservoir in the main Minagish field. In these new discoveries the oil/water contact in the Marrat Reservoir is 1,400–1,500 ft deeper and the oil is lighter (42° API). Structural mapping of the entire western Kuwait region incorporating both 2-D and 3-D seismic data has helped in understanding the off-structure prospectivity of the area. The predominance of EW- and NS-trending strike-slip faults, with very limited vertical throws, are well-recognized throughout the studied 3-D seismic volume. Faults extending into the 2-D seismic data area can thus be mapped with greater confidence. The 2-D/3-D composite structural map of the Jurassic reservoirs highlighted the fact that the Minagish-Rahayiah Trend is further compartmentalized by mostly EW-trending strike-slip faults. The Umm-Roos prospect is one such compartmented faulted closure. The reservoir characteristics of the Marrat Formation were predicted based on a model of the regional depositional setting and by detailed seismic multi-attribute analyses, calibrated with well data from the Minagish and Dharif fields. The fracture potential was also evaluated using map-based curvature and geomechanical analysis. The astounding success in the Umm-Roos discovery has established new off-structure play concepts for exploring entrapment beyond conventional anticlinal traps. The discovery has added a large area of Jurassic prospectivity to Kuwait.