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101.
Application of a Bayesian model to infer the contribution of coalbed natural gas produced water to the Powder River,Wyoming and Montana 下载免费PDF全文
The Powder River Basin (PRB) of Wyoming and Montana contains significant coal and coal bed natural gas (CBNG) resources. CBNG extraction requires the production of large volumes of water, much of which is discharged into existing drainages. Compared to surface waters, the CBNG produced water is high in sodium relative to calcium and magnesium, elevating the sodium adsorption ratio (SAR). To mitigate the possible impact this produced water may have on the quality of surface water used for irrigation, the State of Montana passed water anti‐degradation legislation, which could affect CBNG production in Wyoming. In this study, we sought to determine the proportion of CBNG produced water discharged to tributaries that reaches the Powder River by implementing a four end‐member mixing model within a Bayesian statistical framework. The model accounts for the 87Sr/86Sr, δ13CDIC, [Sr] and [DIC] of CBNG produced water and surface water interacting with the three primary lithologies exposed in the PRB. The model estimates the relative contribution of the end members to the river water, while incorporating uncertainty associated with measurement and process error. Model results confirm that both of the tributaries associated with high CBNG activity are mostly composed of CBNG produced water (70–100%). The model indicates that up to 50% of the Powder River is composed of CBNG produced water downstream from the CBNG tributaries, decreasing with distance by dilution from non‐CBNG impacted tributaries from the point sources to ~10–20% at the Montana border. This amount of CBNG produced water does not significantly affect the SAR or electrical conductivity of the Powder River in Montana. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
102.
P. Hofmann A.Y. Huc B. Carpentier P. Schaeffer P. Albrecht B. Kelly J.R. Maxwell J.S.Sinninghe Damst J.W. de Leeuw D. Leythaeuser 《Organic Geochemistry》1993,20(8)
The lower Oligocene evaporite sequence of the Mulhouse Basin (France) contains organic matter-rich marl deposits. These marls display an overall cyclic variation of sedimentation rate, organic carbon content, hydrogen index and selected molecular parameters over a 30 m thick stratigraphic interval. The integration of all sedimentological and geochemical parameters has allowed the reconstruction and characterization of the paleoenvironment of deposition. The marls were deposited in a perennial lake that was at times connected to the sea. Two organic facies end members could be assigned to a lake stage with a marine connection and a lake stage that received dominantly continental water input. The overall stratigraphic variation in the organic matter content is interpreted to reflect the adaptation of the Oligocene flora to the changing paleoclimate and environmental conditions. 相似文献
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A sequential fractionation procedure employing a series of selected mild organic solvents of different polarity has been applied for the isolation of chemically different organic fractions from a brown coal humic acid. Elemental composition, molecular weight distribution, i.r. and electron spin resonance analysis were carried out on the isolated humic fractions. They were characterized by: (a) a low polydispersity, (b) a decreasing aliphatic and increasing aromatic character along the series, (c) very different molecular weight which significantly correlated with E4/E6 ratios (particle aggregation and molecular association) and free radical concentrations (chemical and biochemical activity). Significant correlations were found between physico-chemical parameters of the isolated humic fractions, i.e. Mn, Mw, E4/E6 ratios, spins/g contents and the dielectric constants of the solvents used. This suggested the efficiency of the applied procedure in isolating chemically different organic fractions from the bulk, original humic acid. 相似文献
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Immature Torbanite and the resistant biopolymer (PRB A) isolated from extant B. braunii were previously compared using bulk spectroscopic methods. In the present work, analysis of 400°C pyrolysis products and pyrolysis residues provided further information on their structure and possible relationships. It appears that such polymers are based upon unbranched, saturated, cross-linked hydrocarbon chains up to C31. In addition to these bridging structures, a substantial part of the alkyl chains is singly bound, as esters of unbranched, saturated or cis unsaturated, even fatty acids. These esters are sterically protected, against chemical degradations, by the network of the bioand geopolymer.Quantitative and qualitative observations derived from 400°C pyrolysis confirm that the chemical structure of PRB A and immature Torbanite are closely related. The pyrolysis residues show a similar evolution and numerous common features are noted, with respect to the nature and the distribution of the major constituents of the pyrolysates (hydrocarbons and fatty acids). Accordingly, Botryococcus provides what seems to be the first example of a close structural relationship between a biopolymer produced in large amounts by an extant alga and the geopolymer of an immature kerogen. The essential role of PRB A in Torbanite formation is ascertained. Moreover, it is found that the resistant biopolymer does not undergo important structural changes during the first stages of diagenesis. Thus, owing to steric protection, the esters of immature Torbanite show a distribution quite close to the one of PRB A esters, with exclusively even constituents and a large contribution of unsaturated acids.Recent observations pointed to the possible genesis of some algal kerogens principally by selective preservation of resistant macromolecules. Such a type of formation is clearly predominant in Torbanite, where the bulk of the fossil organic matter corresponds to a selectively preserved and weakly altered, resistant biopolymer, while incorporation of lipids into the kerogen structure during diagenesis seems to play a minor role. 相似文献
105.
根据钻井中途测试(DST)、重复地层测试(RFT)、镜质体反射率(R0)、流体包裹体分析和粘土矿物X射线衍射全定量分析等综合研究发现,莺-琼盆地YA13-1气田存在4期热流体活动;南侧的崖南地区和西侧的莺歌海盆地是其两个重要的热流体物质源和动力源;多期热流体活动在YA13-1地区不仅造成热异常和物质迁移,而且还引起了不同的有机/无机成岩响应,如骨架颗粒的多期溶蚀作用、至少两期的次生加大作用、粘土矿物转化和有机质热成熟作用异常。第二、第三期热流体因出溶作用形成YA13-1气田大规模的天然气聚集。 相似文献
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中国西北C-3植物的碳同位素组成与年降雨量关系初探 总被引:2,自引:0,他引:2
本文对不同年降雨量环境下生长的藜、独行菜、魁蓟和平车前这4种常见C-3植物的δ13C进行了分析,发现这4种C-3植物的δ13C组成都表现出随年降雨量减少而变重的趋势,其中藜和独行菜的碳同位素组成对降水变化的响应相对要较其它2种植物强烈得多。藜、独行菜和魁蓟的δ13C组成与年降雨量有显著的线性关系,平车前碳同位素组成与年降雨量没有显著的相关性,表明藜、独行菜和魁蓟的δ13C组成可作为年降雨量的替代性指标,平车前的δ13C组成不能作为年降水的替代性指标。 相似文献
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