Factors Affecting Compressional Wave Velocity in Unconsolidated Marine Sand Sediments

Abstract

The influence of porosity, gas content, pressure, and temperature on the compressional wave velocity in unconsolidated marine sand sediments is presented. Velocity behavior is explained from theory. The theoretical behavior is compared with velocity data obtained for sediments in situ and velocity data obtained in the laboratory. The significant conclusions reached in this study are (1) sediment porosity is the most important factor affecting velocity in unconsolidated water‐saturated sand sediments; (2) velocity in a shallow unconsolidated water‐saturated sand sediment is nearly independent of the depth of the water above the sediment (within 1% down to a depth of 1000 ft); (3) velocity in an unconsolidated sand sediment is proportional to the velocity in the sea water saturating the sediment; (4) velocity in an unconsolidated water saturated sand sediment increases with an increase in temperature; and (5) velocity in an unconsolidated sand sediment saturated with a mixture of gas and water is considerably lower than the velocity in a sediment saturated with water.