Sonic velocity, submarine canyons, and burial diagenesis in Oligocene-Holocene coolwater carbonates, Gippsland Basin, southeast Australia

Abstract

Burial diagenetic processes largely control sonic velocity and porosity destruction in the Oligocene-Holocene Seaspray Group carbonates of the Gippsland Basin. Extensive cementation of the carbonates begins at around 300-500 m burial depth, and most macroporosity is filled by calcite cement at a burial depth of around 1.5 km. Sonic velocity data from well logs are strongly correlated with the burial diagenetic processes operating in the carbonates. Above 300-500 m burial depth, sonic velocity increases rapidly with depth, with porosity loss being dominated by mechanical compaction. Below 500 m burial depth, the sonic velocity increases at a lesser rate, with porosity loss being dominated by ..