Terrestrial Carbon Sequestration in Devonian-Mississippian Anoxic Basins: Defining the Relative Importance of Higher Plants in Organic Accumulation in Marine Black Shales

泥盆纪-密西西比河缺氧盆地的陆地碳封存：确定海洋黑色页岩中高等植物在有机积累中的相对重要性(EAR-0310072)S.M.Rimmer、T.J.Algeo、A.Carmo和H.D.Rowaba阿巴拉契亚泥盆纪盆地(ADB)的黑色页岩提供了一个独特的机会来评估在可能(有时)区域性广泛的缺氧盆地中影响水柱条件、生产力和沉积的机制。虽然缺氧的底水条件可能影响了有机碳的积累，但越来越多的证据表明，其他因素对水柱内生物地球化学循环的程度和方式以及沉积模式有显著影响。Algeo和他的同事(1995,2001)提出，泥盆纪晚期-密西西比期早期是地球历史上的一个关键时期，在此期间，来自大陆的营养物质的大量涌入可能引发了海洋环境条件的减少，从而促进了碳固定。这一事件不仅导致海洋环境中生产力水平的提高，而且还增加了有机物质进入盆地的通量，即与高等植物的进化有关的难熔陆地物质的通量。通过综合岩石学、地球化学学和沉积学指标，PI将在ADB内重建晚泥盆世-密西西比河早期的条件。这项拟议的研究将检验这一假设，即陆地高等植物的出现在改变空间广泛、缺氧的海洋环境中有机碳积累模式方面发挥了主导作用。PIs希望做出的重大贡献，也许是独特的贡献，是利用有机岩石学和有机地球化学记录这种陆地殖民的海洋记录，并证明跨越亚行的陆地有机物流入的增加，特别是可能在野火期间形成的氧化物质，可能是地球历史上那个时期丰富的有机沉积物积累的一个比以前认识到的更重要的因素。

EAR-0310072RimmerTerrestrial carbon sequestration in Devonian-Mississippian anoxic basins: Defining the relative importance of higher plants in organic accumulation in marine black shales (EAR-0310072)S.M. Rimmer, T.J. Algeo, A.M. Carmo, and H.D. RoweABSTRACT The black shales of the Appalachian Devonian Basin (ADB) provide a unique opportunity to assess mechanisms that influenced water-column conditions, productivity, and sedimentation in what may have been (at times) a regionally extensive anoxic basin. While anoxic bottom-water conditions may have influenced organic carbon accumulation, growing evidence suggests that other factors contributed significantly to the degree and style of biogeochemical cycling within the water column and to the patterns of sedimentation. Algeo and co-workers (1995, 2001) have proposed that Late Devonian-Early Mississippian time was a pivotal episode in Earth history, during which the enhanced influx of continentally derived nutrients may have triggered reducing conditions in the marine environment and, thereby, contributed to carbon sequestration. Not only did this event lead to higher levels of productivity within the marine environment, but it also provided an enhanced flux of organic matter to the basin, that of refractory terrestrial matter associated with the evolution of higher plants. By integrating petrographic, geochemical, and sedimentological proxies, PIs will reconstruct Late Devonian-Early Mississippian conditions within the ADB. The proposed research will test the hypothesis that the advent of terrestrial higher plants played a commanding role in altering the mode of organic carbon accumulation in a spatially extensive, anoxic marine setting. The significant, and perhaps unique, contribution PIs hope to make is to document a marine record of this terrestrial colonization using organic petrography and organic geochemistry, and demonstrate that an increased influx of terrestrial organic matter across the ADB, particularly oxidized material that may have formed during wildfires, may have been a more important factor in the accumulation of organic-rich sediments during that time in Earth history than previously realized.