BLACK SHALES: ENCHANTED CLAYS, MYSTERIOUS ORGANICS, AND AMAZING NANOCOMPOSITES.

摘要

Black shales can exhibit extremely high contents of organic matter, reaching 25 percent of total organic carbon (TOC). Such exceptional values require very unique association of conditions allowing for organic matter (OM) preservation. Beside conventional environmental factors controlling the rate of supply and decay of organic material in marine sediments such as primar productivity, oxidant concentration, rate of OM particle sinking and burial and productivity (Tyson, 2005), additional mechanisms of OM preservation such as vulcanization of organic compounds and mineral surface effects (Kennedy et al., 2002) may be important. Clay surfaces have strong physicochemical interactions between organic matter (OM) and interlayer sites within expandable clays may provide nanosites for preservation as well as spatial relationships, between clay flocs. The intercalation of OM into interlayer has not been conclusively demonstrated in ancient sediments.