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-密西西比期缺氧盆地陆相固碳：高等植物在海相黑色页岩有机质富集中的相对重要性里默，T.J. Algeo， A.M.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影响水柱条件、生产力和沉积的机制，这个盆地可能（有时）是一个区域广泛的缺氧盆地。虽然缺氧的底水条件可能影响有机碳的积累，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也有重大影响。Algeo及其同事（1995,2001）提出，泥盆纪晚期-密西西比纪早期是地球历史上的一个关键时期，在此期间，大陆来源的营养物质的大量涌入可能引发了海洋环境的减少条件，从而促进了碳封存。这一事件不仅导致了海洋环境中更高水平的生产力，而且还为盆地提供了更强的有机质通量，即与高等植物进化相关的难降解陆地物质通量。通过整合岩石学、地球化学和沉积学指标，pi将重建亚行内晚泥盆世-早密西西比世的条件。该研究将验证一种假设，即在空间广阔、缺氧的海洋环境中，陆生高等植物的出现在改变有机碳积累模式方面发挥了主导作用。pi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，并证明陆地有机质在亚行各地涌入的增加，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段时间富有机物沉积物积累的一个更重要的因素，而不是以前认识到的。

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.