GEOPHYSICS LETTERS

Geophys. Lett., 1 (2008) 21-;53PETROPHYSICAL STUDIES FOR RECOGNIZINGREEF RESERVOIRS IN OIL PROSPECTION INRAS GHARIB, AND SHOAB GHARIB OILFIELDS, GULF OF SUEZ, EGYPTGhalib, M.*; Nadia, M.* and Farrag, Kh.* Cairo University, Faculty a/Science Egypt,Geophysics DepartmentABSTRACTThe present study is concentrated on the Middle MioceneNullipore rock (Hammam Faraun Member) of BelayimFormation in Ras Gharib, and Shoab Gharib oilfields Gulf ofSuez. This Member is taken as example in the present study tocarbonate build-up or reefs. The study is an attempt toillustrate how we can recognize and interpret the section ascarbonate build-up (reefs) by using petrophysical study. Thereare different subjects which most be carried, to reach to the aimof study, which include: Interpret or identify the lithology ofthe section, examine the radioactivity recorded by Gamma raylogs, examine the presence of secondary porosity, and examinetlte vertical and horizontal petrographic variation (zonation) inthe formation or section. The results of these subjects include;the interpreted lithology of the Nullipore section in the studiedarea is limy dolomite(dolomite log response), the section ischaracterized by secondary porosity related to vuggy porosity,gamma ray log record high readings in the interval of thesection which is related to organic matter, the section ischaracterized by vertical and lateral variations in the responsesof the different logging tools which reflect the petrographicvertical and lateral variation in the section which arecharacteristic features to reefs, the evaluation to the sectionindicate suitable porosity and permeability range to the sectionto be as a potential reservoir, also the evaluation to the sectionindicate that it is hydrocarbon bearing in different zones of thesection.