الفهرس | Only 14 pages are availabe for public view |
Abstract Wireline logs of 13 wells from Ras Fanar oil Field were studied to delineate petrophysical attributes of the Middle Miocene Nullipore Member. The lithofacies, porosities and water saturation are determined and the net pay parameters are also estimated. The early diagnesis (dolomitization and leaching) of the leached lime-packstone (NA1 and NA2 zones) undergone enhanced the petrophysical properties sufficiently. This facies appear to be more favorable as hydrocarbon-bearing zones. The dolomitized wackestone facies (NB1 and NB2 zones) have proven to be productive of oil only, (KK84-9, KK84-SE1A, RF-A8b, and RF-A3a well). It is characterized by moderate-good effective porosity values (16-29%), relatively high water saturation (28-38%), thin net pay thicknesses (14.5-25ft at RF-A8b and KK84-9 well, respectively). Whereas, the leached lime-packstone facies represented by zones NA1 and NA2, has proven to be productive of oil and/or gas because of the sufficient effective porosity values (up to 36%), low water saturation (4% at RF-B2 well), thick net pay thickness. The pattern and trend of the various parameters clearly account for the distribution of the hydrocarbon production. Hydrocarbon production in this field is obviously localized on a structural high such as RF-B1 well, but in the others are confined to down-thrown block such as KK84-9 well. The derived parameter distribution maps indicate that the production does not always exist on structurally high areas such as KK84-2 well. The leached lime-packstone (NA) facies is more productive all over the area particular in the up-thrown fault blocks in the eastern part. Whereas, the dolomitized wackestone (NB) facies are locally productive westward at RF-A8b well. Production of hydrocarbons (gas and/or oil) is limited to the northern structure (up-thrown fault blocks) complex in fresh-water-altered packstone (NA) and the down-thrown fault block in the dolomitized carbonate reservoirs (KK84-9 well). |