Using Rock‐Eval 6 pyrolysis for tracking fossil organic carbon in modern environments: implications for the roles of erosion and weathering     

Yoann Copard  Christian Di‐Giovanni  Thomas Martaud  Patrick Albric  Jean‐Emmanuel Olivier 《地球表面变化过程与地形》2006,31(2):135-153

This work relates to the debate on the fossil organic carbon (FOC) input in modern environments and its possible implication for the carbon cycle, and suggests the use of Rock‐Eval 6 pyrolysis as a relevant tool for tracking FOC in such environments. Considering that such a delivery is mainly due to supergene processes affecting the continental surface, we studied organic matter in different reservoirs such as bedrocks, alterites, soils and rivers in two experimental catchments at Draix (Alpes de Haute Provence, France). Samples were subjected to geochemical (Rock‐Eval 6 pyrolysis) investigations and artificial bacterial degradations. After comparing the geochemical fingerprint of samples, geochemical markers of FOC were defined and tracked in the different reservoirs. Our results confirm the contribution of FOC in modern soils and rivers and display the various influences of weathering and erosional processes on the fate of FOC during its exchange between these pools. In addition, the contrasting behaviour of these markers upon the supergene processes has also highlighted the refractory or labile characters of the fossil organic matter (FOM). Bedrock to river fluxes, controlled by gully erosion, are characterized by a qualitative and quantitative preservation of FOM. Bedrock to alterite fluxes, governed by chemical weathering, are characterized by FOC mineralization without qualitative changes in deeper alterites. Alterite to soils fluxes, controlled by (bio)chemical weathering, are characterized by strong FOC mineralization and qualitative changes of FOM. Thus weathering and erosional processes induce different FOM evolution and affect the fate of FOC towards the global carbon cycle. In this study, gully erosion would involve maintenance of an ancient sink for the global carbon cycle, while (bio)chemical processes provide a source of CO₂. Finally, this study suggests that Rock‐Eval 6 pyrolysis can be considered as a relevant tool for tracking FOC in modern environments. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

Landscape predictors of stream dissolved organic matter concentration and physicochemistry in a Lake Superior river watershed     

Paul C. Frost  James H. Larson  Carol A. Johnston  Katie C. Young  Patricia A. Maurice  Gary A. Lamberti  Scott D. Bridgham 《Aquatic Sciences - Research Across Boundaries》2006,68(1):40-51

  相似文献   

介绍一种简易快捷的煤层瓦斯含量的计算方法     

刘援民  王涛 《中国煤田地质》2006,18(3):29-30,49

大量煤层瓦斯解吸资料表明，解吸瓦斯量（Q）与煤样气体解吸时间的开方（θ），呈Q=ab/θ（b＜0）曲线的相关关系一依据这种关系，由现场瓦斯煤样的解吸资料，建立起θ与Q的回归方程，再按《煤层气测定方法（解吸）MT／T77—1994》中的有关规定计算出损失瓦斯及在化验室测试的常温下煤层瓦斯的自然组分、可燃物质量等数据，进而便可求得煤层瓦斯含量值。该方法在江西省丰城矿区石上井田勘探工作中取得了较好的效果。  相似文献   

青海湖底沉积物的矿物物相及有机质保存研究   总被引：2，自引：0，他引：2  

李善营  于炳松Hailiang Dong 刘英超 《岩石矿物学杂志》2006,25(6):493-498

盐湖沉积环境是烃源岩发育的重要地质环境。本文以青海湖湖底沉积物为例，根据有机质与粘土矿物含最及矿物表面积的关系，分析了矿物学因素对盐湖相富有机质沉积物中有机质保存的影响。研究发现：湖底沉积物中有机质丰富，为上层水中的浮游生物和南河流携带束的陆地高等植物两种来源。矿物物相分析发现沉积物中粘土矿物含量达到32．4％，以伊利石为主。沉积物经密度分离后测试发现，有机碳含量与粘土矿物含量及矿物表面积之间具有很好的正相关性，说明粘土矿物吸附是青海湖底沉积物中有机质的主要赋存形式。  相似文献   

消解炉消解-氧化还原滴定法测定土壤样品中有机质   总被引：1，自引：0，他引：1  

熊艳钟夏阳  陈金保 《岩矿测试》2006,25(2):191-192

沿用经典重铬酸钾氧化-外加热法的原理，建立了消解炉消解-氧化还原滴定法测定土壤样品中有机质的方法。实验选择消解温度为180—200℃，消解时间为10—15min。方法用于大批量区域多目标地球化学调查样品中有机质的分析，测试值与标准值相符。对国家土壤标准物质进行测定，方法精密度（RSD，n=8）为1．93％～7．96％。  相似文献   

作物水分与氮素生产函数的实验研究   总被引：7，自引：0，他引：7       下载免费PDF全文

王康  沈荣开  沈言俐  许翠平  覃奇志 《水科学进展》2002,13(3):308-312

在田间水肥耦合试验的基础上,对水分生产函数的概念加以拓宽,提出了水分、氮素生产函数的概念,并建立了最终产量模型和动态产量模型,进行了参数求解,模型模拟结果和田间试验结果符合较好.  相似文献   

A model of low-mass neutron stars with a quark core     

G. B. Alaverdyan  A. R. Arutyunyan  Yu. L. Vartanyan 《Astronomy Letters》2002,28(1):24-29

We consider an equation of state that leads to a first-order phase transition from the nucleon state to the quark state with a transition parameter λ>3/2 (λ=ρ_Q/(ρ_N+P₀/c²)) in superdense nuclear matter. Our calculations of integrated parameters for superdense stars using this equation of state show that on the stable branch of the dependence of stellar mass on central pressure dM/dP_c>0) in the range of low masses, a new local maximum with M_max=0.082_⊙ and R=1251 km appears after the formation of a toothlike kink (M=0.08M_⊙, R=205 km) attributable to quark production. For such a star, the mass and radius of the quark core are M_core=0.005M_⊙ and R_core=1.73 km, respectively. In the model under consideration, mass accretion can result in two successive transitions to a quark-core neutron star with energy release similar to a supernova explosion: initially, a low-mass star with a quark core is formed; the subsequent accretion leads to configurations with a radius of ～1000 km; and, finally, the second catastrophic restructuring gives rise to a star with a radius of ～100 km.  相似文献   

水稻干物质的数值模拟及类型区划   总被引：2，自引：0，他引：2  

高永刚  王飞 《南京气象学院学报》1998,21(4):637-646

干物质积累是水稻经济产量的基础,利用分斯播种资料,运用作物生长模拟方法,根据水稻主要种植区域的光温资料,作出水稻干物质积累的理论计算。通过对干物质积累值的时空规律分析和区划,为分析生物学产量形成的生态条件提供数据。  相似文献   

官地银金矿床氧化带划分的试验研究及物相锰在贫硫化物型银矿床中的应用     

张百胜 《矿产与地质》1998,(5)

官地银金矿床的原生矿石和氧化矿石在矿石颜色、矿物粒度、矿物组合和银金赋存状态均有明显差异。因此,氧化矿石在采矿和选矿上只能采取单采单选的方法。通过官地银金矿床银的物相、铅锌物相和铁锰物相的试验研究,来划分氧化带的范围和确定其埋深。官地银金矿床是应用物相锰来划分氧化带,即锰氧化率＝Ｍｎ４＋／ＴＭｎ×１００％,当锰氧化率≥２５％时划为氧化矿,＜２５％时划为原生矿,这一试验研究成果为官地银金矿床选择采选方案提供科学试验依据。  相似文献   

Organic/ Inorganic Occurrence of Metallic Elements of the Black Shale-Hosted Baiguoyuan Silver-Vanadium Deposit in Xingshan, Hubei     

ZHUANG Hanping  LU Jialan  FU Jiamo  LIU Jinzhong Guangzhou Institute of Geochemistry  Chinese Academy of Sciences  Guangzhou REN Chigang  ZOU Degang The nd Department of Physics  Fudan University  Shanghai  TIAN Weizhi Chinese Academy of Atomic Science  Beijing 《《地质学报》英文版》1998,72(3):299-307

By means of kerogen purification, the proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA), the authors have studied the organic/inorganic occurrence modes of the metallic elements of the Baiguoyuan silver-vanadium deposit hosted in black shale in Hubei Province, China. The result shows that Au, Hg and Ta have a strong tendency to occur organically, with more than 70% of these elements being associated organically. Se, Ga, Ag and Hf are partly associated with organic matter, with more than 20% of them occurring organically. Compared with the above elements, Zn, Cu, As and Sb are weakly associated organically, and tend to be enriched in kerogen. However, Mn, Th, U, V, Co, Cr, Al, Fe and Sc usually occur inorganically. Of the rare earth elements (REE), La, Ce, Tb, Dy, Yb and Lu have stronger ability to be associated with organic matter than Sm and Eu.  相似文献