Anomalous wave velocities in sediments containing gas hydrates

Natural gas and water combine to form an ice-like substance called a gas hydrate under certain conditions of temperature and pressure. These conditions appear to exist over large areas of the ocean bottom. An experiment is described in which artificially formed gas hydrate in shown to cause marked increase in acoustic wave velocity suggesting that anomalously high velocities observed in situ in gassy sediments may indicate the presence of such hydrates.