High Resolution Imaging Integrated Approach to Solve Pay Count and Turbidites Reservoir Architecture Dilemma, Offshore Nile Delta, Egypt

Abstract

Offshore Mediterranean province of Egypt has one of the most promising gas fields in the world; representing deep water turbidite proximal channel sands and distal thinly bedded turbidities sands. Evaluating such reservoirs of thinly bedded formations remains an extremely challenging process. To improve the way of characterizing the reservoirs efficiency; integrating the conventional open hole logs along with the high resolution micro resistivity images will reveal the complexity of such reservoirs. Reservoir characterization in terms of the delineation, architecture and hence the exact pay counting were the main challenges faced in this study. Detailed high resolution electro-facies analysis has been extracted for better understanding of Abu Madi and Kafr-El Sheikh formations respectively in offshore Nile Delta wells. The studied Late Miocene-Pliocene succession shows an overall retrogradational pattern and a fining-upward depositional motif. Twelve main facies associations and sedimentary units are identified. The basal sedimentary unit is equivalent to Messinian Abu Madi Formation and represents a sandy estuarine complex facies association. It was succeeded by Early Pliocene Kafr El Sheikh Formation where submarine channel fill-levee complex prevailed. It was developed during flooding event and relative rise in eustatic sea-level. The intervening silty heterolithics, laminated siltstone, massive claystone with rare sandstone interbeds represent proximal to distal levee depositional suite. These laminated siltstones in these levee deposits are locally gas-bearing. High resolution single well sedimentary facies understanding and pay count using different approaches, have improved the overall depositional regime. This sedimentary analysis using image logs illustrated reservoir architecture for better sand delineation and accurate reserve estimation. Pressure points and samples have been taken over the potential thin bedded tutrbiditic channel levee complex and it shows the presence of gas in this unit. As a result of these integrated analysis; Twenty meter of thin bedded channel levee complex has been perforated and proved to be gas bearing zone. Perforation results revealed the productivity and the economic potentiality of these added thin bedded reservoir pay.

AAPG Datapages/Search and Discovery Article #90194 © 2014 International Conference & Exhibition, Istanbul, Turkey, September 14-17, 2014