King Saud University Repository >
King Saud University >
Science Colleges >
College of Engineering >
College of Engineering >

Please use this identifier to cite or link to this item: http://hdl.handle.net/123456789/13658

Title: Log Evaluation of Low - Resistivity Sandstone Reservoirs
Authors: Hamada, G.M.,
Al-Awad, M.N.J.,
Almalik, M.S.
Keywords: Electric conductivity; Hydrocarbons; Ionic conduction; Microporosity; Nuclear magnetic resonance; Oil fields; Pyrites; Recrystallization (metallurgy); Sandstone; Saturation (materials composition)
Issue Date: 2001
Citation: Proceedings of the Permian Basin Oil and Gas Recovery Conference, pp. 270-279.
Abstract: A careful examination of the mud log and sidewall cores in certain interval of hydrocarbon anomaly, dry oil from low resistivity sands was surprisingly discoverded and confirmed afterward by well testing results. The problem with these sands is that the resistivity logs indicate high water saturation, but water free hydrocarbon will be produced. This paper discusses the different reasons sandstone reservoirs can have low resistivity. The mechanisms resposibles for low resistivity phenomenon are described as being caused by the inclusion of clay or pyrite minerals and as being due to microporosity. Clean bearing sandstone has high resistivity, but when this rock contains clay, or heavy minerals such as pyrite, the resistivity can become low. Pyrite shows a good electrical conductivity, that is usually comparable to or even higher than the conductivity of formation water, and can therefore have a larger effect than shale. In this work, different shaly sand models will be discussed and applied in two field examples to correct the calculated water saturation from shale effect to get the true water saturation level. The contribution of NMR log in solving problems of low resistivity microporisity sandstone reservoirs was iluustrated by a third field example.
URI: http://hdl.handle.net/123456789/13658
Appears in Collections:College of Engineering

Files in This Item:

File Description SizeFormat
7.doc38.5 kBMicrosoft WordView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.


DSpace Software Copyright © 2002-2009 MIT and Hewlett-Packard - Feedback