Effects of rock-fabrics on petrophysical properties of a carbonate-rock inmeteoric diagenetic zone (Oligocene Aquitain limestone, France)

120 samples of three quarries of the Oligocene Aquitain limestone were subj ected to petrographic, petrophysical and chemical analyses. Strong variatio ns of depositional and diagenetic textures were observed. Four main deposit ional textures characterize this limestone : mudstone-wackestone, packstone , packstone-grainstone and grainstone. Thr diagenetic transformations recog nized and specially meteoric leaching increases the heterogencity of porous medium. The <<Pierre de Bordeaux>> a shows a high variation of porosity (1 2,8% to 42,51%), permeability (4,27 to 4755 mD), specific surface (0,78 to 3,73 m(2)/g) and distribution of pi,re throats (from monomodal to three mod al distribution). Petrophysical properties depend strongly on depositional and diagenetic patterns. Textures with two and three modal distribution of porous medium, packstone-grainstone and grainstone have the best reservoir properties. The meteoric dissolution associated to microfracturing improves strongly both the macroporosity, permeability in mudstone-wackestone and p ackstone rind increases the pore space complexity in all textures.