Predicting the thickness of sand strata in a sand-shale interbed reservoir based on seismic facies analysis
File(s)2020_JGE_Li_Gao_Wang_gxaa015.pdf (2.65 MB)
Published version
Publication available at
Author(s)
Li, H
Gao, R
Wang, Y
Type
Journal Article
Abstract
Seismic facies analysis is of great significance for the detection of residual oil in a sand-shale interbed reservoir. In this study, we propose to predict spatial distribution of sand thickness over a reservoir, based on seismic facies analysis. The target reservoir is a thin sand-shale interbed layer, and the layer thickness varies between 2 and 10 m. The thickness of sand strata within the reservoir layer appears to have a fragmentary distribution in lateral space. Thin thickness and fragmentary distribution are two factors that cause difficulty in sand thickness prediction. To tackle this problem, this study adopted a three-stage strategy. First, the reservoir over the entire study area was classified into five different lithofacies, following sedimentary microfacies analysis against the characteristics of gamma-ray logging data, and the corresponding seismic responses were meticulously depicted. Then, exploiting these seismic responses, or seismic facies, the spatial distribution of the gamma-ray values was evaluated within the thin sand-shale interbed reservoir. Finally, the spatial distribution of the sand thickness was predicted according to the spatial distribution of the gamma-ray values. The prediction was conducted independently for each seismic facies, rather than in a non-discriminatory manner. Comparing the prediction to the actual evaluation derived from well-logging data demonstrated that the thickness distribution resulting from seismic data has a high accuracy, because of the facies-based analysis.
Date Issued
2020-08-01
Online Publication Date
2020-07-20T08:52:07Z
Date Acceptance
2020-02-26
ISSN
1742-2132
Publisher
Oxford University Press (OUP)
Start Page
592
End Page
601
Journal / Book Title
Journal of Geophysics and Engineering
Volume
17
Issue
4
Copyright Statement
© The Author(s) 2020. Published by Oxford University Press on behalf of the Sinopec Geophysical Research Institute. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium,provided the original work is properly cited
Identifier
https://academic.oup.com/jge/advance-article/doi/10.1093/jge/gxaa015/5828674
Subjects
0404 Geophysics
0905 Civil Engineering
Geochemistry & Geophysics
Publication Status
Published
Date Publish Online
2020-05-04