The use of pyrolysis and barium distributions to assess the areal extent of drilling fluids in surficial marine sediments

The influence of drilling fluid dispersion on the chemistry of surficial sediments was determined by an integrated study of organic and inorganic parameters. Pyrolysis characteristics and barium, organic carbon, and carbonate content were determined for sediments associated with six drilling sites in coastal Gulf of Mexico waters. The areal extent and magnitude of influence of dispersed fluids were related to water depth, prevailing currents, density of the dispersed material, history of the drill site and platform-induced biological activity. The potential use of pyrolysis techniques for defining the impact area and the various types of inputs derived from off-shore drilling operations was demonstrated.