A multiscale analysis of a fracture pattern in granite: A case study of the Tamariu granite, Catalunya, Spain. (September 2015)

• Record Type: Journal Article
• Authors: Bertrand, Lionel; Géraud, Yves; Le Garzic, Edouard; Place, Joachim; Diraison, Marc; Walter, Bastien; Haffen, Sébastien
• Is Part Of: Journal of structural geology. Volume 78(2015:Sep.)
• Page Start: 52
• Page End: 66
• Publication Date: 2015-09
• Subjects: Fracture network in granite -- Reservoir analogue -- Multiscale analysis -- Length distribution -- Relation between 1D and 2D sampling method; Geology, Structural -- Periodicals; Géomorphologie structurale -- Périodiques; Geology, Structural; Periodicals; 551.805
• DOI: 10.1016/j.jsg.2015.05.013
• Languages: English
• ISSNs: 0191-8141

Abstract

Abstract: The in-depth investigation of fractured reservoirs is mainly limited to geophysical data that is in 3D and mostly on the scale of hundred meters to several kilometers or boreholes data that is in 1D and at meter to lower scale. The study of outcropping analogues of buried reservoirs is therefore a key tool for the characterization of the fault and fracture network at the reservoir scale. Tamariu granite has been the subject of this study with the aim to analyse faults and fractures from seismic to borehole scale. With the combination of satellite picture at different resolution and field study, we perform a statistical analysis focused of the length and orientation from infra centimeter crack to hundred kilometer length fault. On the whole range of scale studied, i.e. on 7 orders of magnitude, we have defined a length distribution following a power-law with an exponent a = −2. On the contrary to the length that can be modelled with a unique law, the orientation data shows a variation depending on the scale of observation: as the fault and fracture sets are suitable from the regional faults to the centimeter crack, the proportion of the sets varies at each scale of observation. Highlights: Statistical analysis of faults and fractures from regional to centimetre scale. Length distribution following a power law over 7 orders of magnitude. Combinaison of 1D measurement methods (scan lines) and 2D (maps). Fracture orientation variability between the different scale of observation.