Figure F3. Total organic carbon (TOC) concentration and isotopic data of sediments from Sites 1040, 1254 and 1255. Patterned areas represent fault zones and the décollement. A. Downhole concentration variation of TOC. The values are slightly higher than those of Kimura, Silver, Blum, et al. (1997). B. Downhole variation of delta13C. VPDB = Vienna Peedee belemnite. C. TOC/total nitrogen (TN) variation with depth. Sediments from 1040, 1254, and 1255 show congruent values in TOC concentrations, delta13C values, and TOC/TN ratios. Note the downhole decrease in TOC/TN ratios, largely related to downhole increase in TN concentration, in the uppermost ~100 m.

Figure F3. Total organic carbon (TOC) concentration and isotopic data of sediments from Sites 1040, 1254 and 1255. Patterned areas represent fault zones and the décollement. A. Downhole concentration variation of TOC. The values are slightly higher than those of Kimura, Silver, Blum, et al. (1997). B. Downhole variation of

¹³C. VPDB = Vienna Peedee belemnite. C. TOC/total nitrogen (TN) variation with depth. Sediments from 1040, 1254, and 1255 show congruent values in TOC concentrations,

¹³C values, and TOC/TN ratios. Note the downhole decrease in TOC/TN ratios, largely related to downhole increase in TN concentration, in the uppermost ~100 m.