Prediction of principal metal-binding solid phases in estuarine sediments from color image analysis

A novel application of image analysis technology to the semiquantitative determination of the strong metal-binding phases of hydrous ferric oxides and acid-volatile sulfides in muddy estuarine sediments is presented. Sediment cores were split in the laboratory, photographed in cross-section, and subsampled for solid-phase analyses. The images were processed using commercially available software packages. Concentrations of FeOOH and AVS were found to be linearly related to elementary color parameters (saturation and intensity, respectively) at corresponding points on the images. Spatially resolved information on metal-binding capacity can thereby be estimated from such images; selected depth profiles are generated as examples.