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TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractThe Minagish field has several reservoirs with oil accumulated primarily in lower Cretaceous Minagish Oolite -middle member (MMO) rocks. This giant carbonate hydrocarbon accumulation in the Minagish field was discovered in 1958 and accounts for > 80% of oil production in the Field. The Lower Minagish end member consists largely of clean to slightly argillaceous and/or carbonaceous fine grained peloidal packstones that were deposited in a low energy platform setting equivalent to very gently sloping outer ramp.Two significant flooding events divide the Lower Minagish Formation into three main productive zones upper, middle and lower. The contact between lower and middle member is an irregular one with a gradual diagenetic transition from limestone to tight dolostone.The Lower member has a gross pay of about 220ft above recorded lowest known oil (LKO) at about 10,000 feet tvdss close to the top of the Makhul carbonates (which forms the bottom seal of the reservoir). The recent conventional cores and image log data from the crest of the structure show that the Lower Minagish has faults and fractures which could provide permeability assist. There are 130 wells have been drilled in this field targeting Minagish Oolite (middle member); however 10 wells have recently been deepened to evaluate the oil potential of the Lower Minagish (LMN) and the underlying Makhul Formations. Five wells tested in the upper and middle zones have tested at production rates in the range of 400 to 4300 BOPD with the oil from the upper and middle zones having an API of 31° to 20.5°. This is significantly lower than the Minagish Oolite oil with an API range of 28° to 32°. This indicates probably a later reservoir filling than the Minagish Oolite oil emplacement. The discovery of this new oil is expected to enhance the STOIIP of the field. Although only wells in the northern block have been drilled and tested so far, the 3-D Seismic mapping suggests possible deeper oil down to in the southern block.

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