Optimising CSG development: quantitative estimation of lithological and geomechanical reservoir quality parameters from seismic data
E. Bathellier A , J. Downton A and G. Castillo ACGGVeritas.
The APPEA Journal 52(2) 675-675 https://doi.org/10.1071/AJ11089
Published: 2012
Abstract
Within the past decade, new developments in seismic azimuthal anisotropy have identified a link between fracture density and orientation observed in well logs and the intensity and orientation of the actual anisotropy. Recent studies have shown a correlation between these measurements that provide quantitative estimations of fracture density from 3D wide-azimuth seismic data in tight-gas sand reservoirs.
Recent research shows the significance of advanced seismic processing in the successful recovery of reliable fracture estimations, which directly correlates to borehole observations. These quantitative estimations of fracture density provide valuable insight that helps optimise drilling and completion programs, particularly in tight reservoirs. Extending this analysis to CSG reservoirs needs to consider additional reservoir quality parameters while implementing a similar quantitative approach on the interpretation of seismic data and correlation with borehole logging observations.
The characterisation of CSG plays involves the understanding of the reservoir matrix properties as well as the in-situ stresses and fracturing that will determine optimal production zones. Pre-stack seismic data can assist with identifying the sweet spots—productive areas—in CSG resource plays by detailed reservoir-oriented gather conditioning followed by pre-stack seismic inversion and multi-attribute analysis. This analysis provides rock property estimations such as Poisson’s ratio and Young’s modulus, among others, which in turn relate to quantitative reservoir properties such as porosity and brittleness.
This study shows an integrated workflow based on pre-stack azimuthal seismic data analysis and well log information to identify sweet spots, estimate geo-mechanical properties, and quantify in-situ principal stresses.
Eric Bathellier is a technical marketing manager for the CGGVeritas land division. He has 20 years of experience in the petroleum industry. Prior to joining CGGVeritas in 1998, Bathellier worked with Total as a research geophysicist from 1991 to 1995 and with Createch Industrie (now Sercel) as a sales engineer from 1996 to 1997. His main areas of interest are land acquisition technology, 4D seismic and integrating geophysics with reservoir engineering. He holds an MSc (geoscience) from the IFP School and a PhD (geomechanics) from the Ecole Centrale de Paris. |
Jon Downton is a senior research advisor at CGGVeritas Hampson Russell. His main interest is reservoir geophysics and its associated seismic. He has presented numerous papers at SEG, EAEG, and CSEG conferences, for which he has received best paper awards. He obtained his PhD from the University of Calgary in 2005 and his BSc (geophysics) from the University of Alberta in 1985. He is a past president of the Canadian Society of Exploration Geophysicists (CSEG). |
Gabino Castillo is a geophysical advisor at CGGVeritas Hampson-Russell. He holds a master’s degree (geophysics) (Institut Francais du Pétrole). His experience includes seismic reservoir characterisation, pore pressure prediction, interpretation, petrophysics, pre-stack depth migration, time processing, and research and geophysics development. He joined CGGVeritas in 1999 as part of the depth-imaging group. He was also part of the time processing group for two years prior to joining the reservoir group performing AVO, rock physics and AVO modelling, seismic inversion, pore pressure prediction, and other. He headed up the seismic reservoir characterisation and Hampson-Russell group in Villahermosa, Mexico and served as the manager of the technology centre in the Villahermosa office. He has led the development and users support of the AVO analyser, a tool for computing and interpreting AVO anomalies used worldwide for reservoir and processing teams. He is now North America services manager. |
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