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Please cite this article as: bertrand, L., geraud, Y., Le Garzic, E., Place, J., Diraison, M., Walter, B., Haffen, S., A multiscale analysis of a fracture pattern in granite: A case study of the Tamariu granite,The in-depth investigation of fractured reservoirs is mainly limited to geophysical data that 2 is in 3D and mostly on the scale of hundred meters to several kilometers or boreholes data that 3 is in 1D and at meter to lower scale. The study of outcropping analogs of buried reservoirs is 4 therefore a key tool for the characterization of the fault and fracture network at the reservoir 5 scale. Tamariu granite has been the subject of this study with the aim to analyze faults and 6 fractures from seismic to borehole scale. With the combination of satellite picture at different 7 resolution and field study, we perform a statistical analysis focused of the length and 8 orientation from infra centimeter crack to hundred kilometer length fault. On the whole range 9 of scale studied, i.e. on 7 orders of magnitude, we have defined a length distribution following 10 a power-law with an exponent a= -2. On the contrary to the length that can be modeled with a 11 unique law, the orientation data shows a variation depending on the scale of observation: as 12 the fault and fracture sets are suitable from the regional faults to the centimeter crack, the 13 proportion of the sets varies at each scale of observation.

[1] The hydraulic and electrical properties of pyroclastic rocks have been investigated in laboratory on a representative sampling of Montagne Pelée (Martinique, France) deposits with renewed interest in geophysical applications. This sampling covers all the lithologic units of this volcano: lava dome and lava flows, pumices from ash-andpumice fall and flow deposits, lava blocks from block-and-ash flow and Peléean ''nuées ardentes'' deposits, scoriae from scoria flow deposits. The connected porosity varies over a wide range from 3 to 62%. The unconnected porosity is important only on pumices where it can reach 15%. The permeability covers more than 5 orders of magnitude, ranging from 10 À16 to 35 Â 10 À12 m 2 . The higher values are obtained on lava blocks and the scoriae, even if these rocks are less porous than the pumices. The formation factor ranges from 7 to 1139. The transport properties of these rocks are slightly correlated with porosity. This indicates that these properties are not only controlled by the connected porosity. To connect the transport properties to the textural characteristics of the pore network of pyroclastic rocks, different models, based on geometrical considerations or percolation theory, were tested. The pore access radius distribution and the tortuosity control the transport properties of pyroclastic rocks. Consequently, the models (electric and hydraulic) based on the concept of percolation (e.g., the models of Katz and Thompson), apply better than the equivalent channel model of Kozeny-Carman. In addition, the difference in transport properties observed on lava blocks and pumices confirms that the mechanisms of degassing and vesiculation are different for these two types of rock.

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S U M M A R YPore magnetic fabric is a well-established technique for the determination of pore elongation and preferred directions for migration of the interstitial fluids. This study further exemplify this technique on a set of the Nubia sandstones through a comparison with the pore anisotropy obtained from measuring permeability in three orthogonal directions in a gaz permeameter. The Nubia sandstones are represented in Tushka area (South Egypt) by quartz arenite of large porosity (29-40 per cent) which was measured on thin sections parallel and perpendicular to the bedding plane and petrophysically by helium pycnometry and ferrofluid injection at 1 bar pressure.Petrographically, there is a detectable difference between the porosity values in the bedding plane and in the perpendicular direction indicating inhomogeneity in the pore space network distribution.The petrophysical studies indicate large porosity and permeability values with some differences between the helium and ferrofluid porosity due to presence of micro pore spaces not accessible for the ferrofluid molecules having relatively high diameters and injected at low pressure.An overall agreement is observed between the permeability anisotropy and the magnetic grain and pore fabrics (magnetic anisotropy measured before and after ferrofluid injection). The three fabrics are mainly dominated by a bedding parallel foliation. In a few cases maximum permeability appears to be perpendicular to bedding. Within the bedding plane, maximum pore elongation direction from ferrofluid injection is NNW for Adindan and Kesieba formations and NW for Abu Simbil Formation. The maximum pore elongation direction for Abu Ballas samples showed a direction fluctuating around the E-W direction, the main fault trends in Tushka area. The pore fabric of Abu Ballas formation seems therefore to be structurally controlled, while it would be originated from palaeocurrent directions in the other formations.

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The Upper Ordovician glacial record of southern Jordan (Ammar Fm.) essentially consists of palaeovalley infills and of a subordinate time-transgressive fluvial to shallow-marine succession overstepping both the palaeovalleys and interfluvial areas. Valley size (depth, 60-160 m; width, 1-3 km), steep (20-508) margins, internal organization and depositional facies point to an origin as tunnel valleys. The tunnel valleys are infilled by either fluvioglacial sandstones or fluviodeltaic coarsening-upward successions including fine-grained clayey sediments. Re-occupation of previous valleys is evident in places. At least three generations of tunnel valleys are inferred from cross-cutting relationships, although they most probably only reflect temporary standstills and minor re-advances related to the overall recession following the main glacial advance recorded in Saudi Arabia. Petrophysical measurements indicate that higher permeabilities are located in the glacially related strata (1.5-3 darcy in fluvioglacial infills), with a somewhat reduced porosity (22-28%) relative to the preglacial sandstones owing to a higher clay content, probably of diagenetic origin. Sandstone amalgamation, however, gives the fluvioglacial sandstones a high reservoir quality.