More than 250 plugs from outcrops and three nearby boreholes in an undisturbed reef of Miocene (Tortonian) age were quantitatively analyzed for texture, mineralogy, and acoustic properties. We measured the P- and S-waves of carbonate rocks under dry (humidified) and brine-saturated conditions at [Formula: see text] effective pressure with an ultrasonic pulse transmission technique [Formula: see text]. The data set was compared with an extensive database of petrophysical measurements of a variety of rock types encountered in carbonate sedimentary sequences. Two major textural groups were distinguished on the basis of trends in plots of compressional-wave velocity versus Poisson’s ratio (a specific ratio of P-wave over S-wave velocity). In granular rocks, the framework of depositional grains is the main medium for acoustic-wave propagation; in crystalline rocks, this medium is provided by a framework of interlocking crystals formed during diagenesis. Rock textures are connected to primary depositionalparameters and a diagenetic overprint through the specific effects on Poisson’s ratio. Calculating acoustic velocities using Gassmann fluid substitution modeling approximates measured saturated velocities for 55% of the samples (3% error tolerance); however, it shows considerable errors because shear modulus changes with saturation. Introducing brine into the pore space may decrease the shear modulus of the rock by approximately [Formula: see text] or, alternatively, increase it by approximately [Formula: see text]. This change in shear modulus is coupled with the texture of the rock. In granular carbonates, the shear modulus decreases; in crystalline and cemented carbonates, it increases with saturation. The results demonstrate the intimate relationship between elastic behavior and the depositional and diagenetic properties of carbonate sedimentary rocks. The results potentially allow the direct extraction of granular and crystalline rock texture from acoustic data alone and may help predict rock types from seismic data and in wells.

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More than 200 plugs from outcrop and a nearby borehole in a carbonaceous siliciclastic interval of Late Jurassic (Kimmeridgian to Tithonian) age were quantitatively analyzed for texture, mineralogy, and acoustic properties. Our primary goal was to study the effect of clay (fraction smaller than 8 μm), silt/sand (fraction larger than 8 μm), and carbonate on the acoustic properties. The quantitative nature and volume of the data made it possible to observe four‐dimensional relationships in contoured ternary diagrams. Primary control on the acoustic properties is exerted by porosity, but the trend of this relationship significantly deviates from popular velocity transforms. The contribution of clay, silt/sand, and carbonate particular material and cement explains the remaining variation in acoustic properties. Although no clear linear thresholds are defined, a general trend is that clay and carbonate content have opposite and overlapping effects on acoustic properties, the influence of clay content progressively increases with decreasing carbonate content, and visa versa. With increasing carbonate content, the variation of acoustic velocity at a given porosity value increases to nearly twice of that in the clay‐dominated sediment. Traditional classification boundaries are present but strongly overprinted by this interplay between clay and carbonate. This study may have important implications for porosity and lithofacies prediction from wireline logs in similar mixtures of sediment. In addition, the quantitative character of the textural and mineralogical data may provide a direct link from acoustic properties to the primary depositional system and sequence stratigraphy.