Exploration of Architecture and Connectivity of Cleat Arrays in Coals of The Lorraine CBM Play by the Means of X-Ray Computer Tomography
V.A. Pryvalov, J. Pironon, A. Izart and C. Morlot
Event name: 79th EAGE Conference and Exhibition 2017
Session: Fractured Reservoirs
Publication date: 12 June 2017
Info: Extended abstract, PDF ( 999.79Kb )
Price: € 20
The Lorraine Basin is one of the largest geologically and commercially important coalfields in the Europe. It has the potential to host unconventional plays including coalbed methane. Nearly all CBM plays are affected in some way by natural fractures sets or cleat, which is just a miner's term for closely spaced fractures or joints in coal. Cleat systems can be traced throughout wide diapason of scales from visually evident into nanoscale levels. A proper understanding of natural cleat patterns is a key factor for estimating of the producibility of coalbed methane gas reservoirs. To explore the architecture of solid coal samples we used X-ray computed tomography with resolutions of 30, 10 and 2 microns. The X-ray CT is a non-destructive technique of inspection of internal structure of solid specimen based on recording abnormal attenuations levels of X-rays after passing them through a specimen, which are dependent on density contrasts within studied specimen. Microfissures are often sealed by mineralization possessing drastic density contrast on the background of coal matter. We propose 3-D mapping of fractal dimension for cleat arrays as a connectivity 3-D measure, which could useful for ensuring technical decisions for efficient exploration and exploitation of CBM reservoirs.