Figure 3From: Reduction of nitrogen compounds in oceanic basement and its implications for HCN formation and abiotic organic synthesisDissolved nitrate concentration in sediment pore fluids at open-ocean ODP Sites 1225 and 1231. The nitrate values show that fresh seawater is channeled upwards into deep-sea sediments via the rocks underneath (from D'Hondt et al., 2003 [13], used with permission of IODP).Back to article page