Jeffrey L. Bada
Srcipps Institution of Oceanography and Institute of Marine Resources
University of California, San Diego
La Jolla, CA 92093, USA.
Geochimica et Cosmochimica Acta (1981) 45: 1847-1854.
Received: 14 January 1981.
Accepted in revised form: 26 May 1981.
The occurrence and distribution of low molecular weight alpha-hydroxy carboxylic and dicarboxylic acids was studied in reducing marine sediments collected in the Santa Barbara Basin and the Cariaco Trench. Four compounds were found to occur in both basin sediments: glycolic, lactic, oxalic and succinic acids. In general, concentrations were low (<1 µmole/g for the hydroxy acids and <100 µmole/g for the dicarboxylic acids), and generally decreased with depth. Subsurface maxima were observed for lactate and succinate in the Santa Barbara Basin. Both the vertical profiles and lactate enantiomer ratios suggested microbial origin and control for the distribuiton of these compounds. A preliminary model for the microbial mediation of the early diagenesis of organic compounds in reducing marine sediments is presented.
We thank Andy Soutar and James Herring for providing the Santa Barbara Basin cores. The Cariaco Trench samples were obtained from the DSDP curator at SIO. Ed Sholkovitz kindly provided the map used in Figure 1. The development of the analytical procedures used in this work was supported by the Office of Naval Research (N00014-75-C-0152).