Implementation of a Petrographical and Petrophysical Workflow Protocol for Studying the Impact of Heterogeneity on the Rock Typing and Reservoir Quality of Reefal Limestone:A Case Study on the Nullipore Carbonates in the Gulf of Suez  

作　　者：Mona G.SAFA Bassem S.NABAWY Ahmed M.K.BASAL Mohammad A.OMRAN Aref LASHIN 

机构地区：[1]Geology Department,Faculty of Science,Damietta University,New Damietta City,Egypt [2]Department of Geophysical Sciences,National Research Centre,Dokki,Cairo,Egypt [3]Petroleum and Natural Gas Engineering Department,College of Engineering,King Saud University,Riyadh 11421,Saudi Arabia [4]Benha University,Faculty of Science,Geology Department,Benha,Egypt

出　　处：《Acta Geologica Sinica(English Edition)》2021年第5期1746-1762,共17页地质学报（英文版）

基　　金：the Researchers Supporting Project number(RSP-2020/92),King Saud University,Riyadh,Saudi Arabia。

摘　　要：This study focuses on the heterogeneity of the middle Miocene syn-rift Belayim nullipore(reefal)marine sequences in the Gulf of Suez and its impacts on reservoir quality.The sequences consist of coralline algal reef limestones with a highly complex dual-porosity system of primary and secondary porosities of widely varying percentages.To achieve a precise mathematical modeling of these reservoir sequences,a workflow protocol was applied to separate these sequences into a number of hydraulic flow units(HFUs)and reservoir rock types(RRTs).This has been achieved by conducting a conventional core analysis on the nullipore marine sequence.To illustrate the heterogeneity of the nullipore reservoir,the Dykstra-Parsons coefficient(V)has been estimated(V=0.91),indicating an extremely heterogeneous reservoir.A slight to high anisotropy(λ_(k))has been assigned for the studied nullipore sequences.A stratigraphic modified Lorenz plot(SMLP)was applied to define the optimum number of HFUs and barriers/baffles in each of the studied wells.Integrating the permeability-porosity,reservoir quality index-normalized porosity index(RQI-NPI)and the RQI-flow zone indicator(RQIFZI)plots,the discrete rock types(DRT)and the R35 techniques enable the discrimination of the reservoir sequences into 4 RRTs/HFUs.The RRT4 packstone samples are characterized by the best reservoir properties(moderate permeability anisotropy,with a good-to-fair reservoir quality index),whereas the RRT1 mudstone samples have the lowest flow and storage capacities,as well as the tightest reservoir quality.

关 键 词：reservoir heterogeneity nullipore rock typing hydraulic flow units Dykstra-Parsons coefficient stratigraphic modified Lorenz plot(SMLP) 

分 类 号：P618.13[天文地球—矿床学]