TY - JOUR T1 - The persistence of memory: The fate of ancient sedimentary organic carbon in a modern sedimentary system JF - Geochimica Et Cosmochimica Acta Y1 - 2003 A1 - Blair, N. E. A1 - Leithold, E. L. A1 - Ford, S. T. A1 - Peeler, K. A. A1 - Holmes, J. C. A1 - Perkey, D. W. AB - The cycle of organic carbon burial and exhumation moderates atmospheric chemistry and global climate over geologic timescales. The burial of organic carbon occurs predominantly at sea in association with clay-sized particles derived from the erosion of uplifted continental rocks. It follows that the history of the fine-grained particles on land may bear on the nature of the organic carbon buried. In this study, the evolution of clay-associated organic matter was followed from bedrock source to the seabed in the Eel River sedimentary system of northern California using natural abundance C-13 and C-14 tracers. Approximately half of the fine-grained organic carbon delivered to the shelf is derived from ancient sedimentary organic carbon found in the uplifted Mesozoic-Tertiary Franciscan Complex of the watershed. The short residence time of friable soils on steep hill slopes, coupled with rapid sediment accumulation rates on the shelf-slope, act to preserve the ancient organic carbon. A comparable quantity of modem organic carbon is added to particles in the watershed and on the shelf and slope. The bimodal mixture of ancient and modem C in soils and sediments may be characteristic of many short, mountainous rivers. If the Eel River chemistry is typical of such rivers, more than 40 Tg of ancient organic C may be delivered to the world's oceans each year. A flux of that magnitude would have a significant influence on marine and global C-cycles. Copyright (C) 2003 Elsevier Science Ltd. VL - 67 IS - 1 N1 - 634jvTimes Cited:143Cited References Count:63 JO - The persistence of memory: The fate of ancient sedimentary organic carbon in a modern sedimentary system ER -