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基于大庆油田三元复合驱采出污水回注对地层存在的损害现象,研究了污水回注渗透率的影响因素。采用室内水驱实验方法,对三元复合驱采出污水中悬浮物、油、碱、聚合物等因素进行了分析,阐述了各种成分对渗透率的影响机理。结果表明,悬浮物颗粒会堵塞孔隙喉道,油产生的“贾敏效应”将增大油水流动阻力,碱与岩石及黏土矿物问的物理化学作用会使地层结垢,聚合物在岩芯中的吸附和滞留共同造成地层渗透率的下降。因此,建议将三元复合驱采出污水中悬浮物、油、碱、聚合物等处理合格后再进行回注,以减轻对地层的损害。 相似文献
23.
太湖入湖河口和开敞区CDOM吸收和三维荧光特征 总被引:13,自引:3,他引:13
应用吸收和三维荧光光谱对2007年夏季太湖入湖河口和大太湖开敞区有色可溶性有机物(CDOM)浓度及来源进行研究.结果表明,河口区和开敞区CDOM吸收系数a(355)存在显著空间差异,河口区明显大于开敞(ANOVA,P<0.001),a(355)最大值出现在大浦河口和竺山湾漕桥河几附近,最小值出现在东太湖和胥口湾.a(355)与溶解性有机碳、化学耗氧量浓度存在显著正相关.所有样品一般都含有4个明显的荧光峰,包括1个可见光区的类腐殖质荧光C峰,1个紫外光区的类腐殖酸荧光A峰,2个类蛋白荧光B峰和D峰.河口区外源输入的类腐殖质荧光非常强,最著大于开敞区(ANOVA,P<0.05).而河口区和开敞区类蛋白荧光没有显著性差异,反映开敞区除外源河流输入外,内源生物降解等对类蛋白荧光贡献增加.在河口区B、C峰的比值r(B/C)/b于1,均值为0.62±0.14、在开敞区r(B/C)除12#是0.92,其他值均大于1,均值为1.12±0.13,初步判断r(B/C)可以作为区分CDOM来源的重要参数.CDOM吸收a(355)与类腐殖质荧光C峰、A峰均存在极显著的正相关,而与类蛋白荧光相关性则明显下降,与D峰存在显著正相关,与B峰没有显著相关. 相似文献
24.
塔木察格盆地的塔南凹陷油气资源丰富,具有很大的勘探开发潜力。塔南凹陷发育多套烃源岩(包括铜钵庙组、南屯组一段和二段、大磨拐河组),针对各套烃源岩基本特征及形成条件的研究较为薄弱。本次收集了大量研究区烃源岩的有机地球化学数据,对塔南凹陷各套烃源岩的基本特征、有机质来源和沉积环境开展了详细研究。结果表明,塔南凹陷烃源岩的有机质丰度较高,以好烃源岩和优质烃源岩为主;铜钵庙组和南一段的有机质类型以Ⅱ1型为主,南二段和大磨拐河组以Ⅱ2型和Ⅲ型为主;有机质总体处于低成熟—成熟阶段;烃源岩中的有机质为低等水生生物和陆源高等植物的混合来源;烃源岩沉积时期的水体为淡水且总体处于弱还原—弱氧化的环境,其中南屯组沉积时期比铜钵庙组和大磨拐河组沉积时期的水体环境要更偏氧化一些。 相似文献
25.
The so called bituminous salts occurring in the Kłodawa dome, located in Central Poland, differ from the surrounding salts by their colour change from light to dark brown. This colour is associated with an extremely large amount of hydrocarbon, mainly located in the inclusions. The presence of numerous fluid inclusions has been documented in previous petrologic studies, distinguishing seven main types of fluid inclusion assemblages (FIA) in terms of size, shape as well as the ratio of filling material. However, four types of inclusions were selected in the current investigations according to their unusual optical behaviour. Raman micro-spectroscopy a modern, non-destructive method was used for investigating a single inclusion being a part of FIA. Presented in this paper Raman spectra revealed a unique pattern of bands characterizing the content of the inclusions. The hydrocarbons show a very complex character reflected in the appearance of a strong fluorescence background. A well-marked heterogeneity characterized the inclusions, by diversity in the intensity of the background and in the pattern of the bands characterizing the presence of certain components. One can distinguish the presence of carbonaceous matter showing the different degrees of order. The depth profile and the analysis of the various points of the inclusions indicate that the carbonaceous matter is not evenly distributed in the inclusions but forms a thin, disorganized film on their walls. This film was also found in sites where the inclusions are filled with brine. The certain characteristics associated with the presence of the incipient phase transformation of the organic matter, or slightly transformed organic matter and the lack of light hydrocarbons as well as a number of petrologic features of inclusions indicate that these salt rocks have been subdivided into thermal transformations, accompanied by the recrystallization of the halite and the escape of the more volatile compounds such as methane, ethane, etc. 相似文献
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27.
B. Kmpfer 《Astronomische Nachrichten》1989,310(3):203-212
In einem thermodynamischen Modell wird die Flavor-Zusammensetzung der stark wechselwirkenden Materie während des kosmischen Confinement-Übergangs behandelt. Thermisches, mechanisches und chemisches Gleichgewicht vorausgesetzt, kann der Anteil von strange-Teilchen analysiert werden. Aufgrund des Gleichgewichts in Hinblick auf ΔS = 0 und ΔS = 1 schwache Wechselwirkungen hängen die verschiedenen Flavor-Anteile stark von dem wenig bekannten Leptonenüberschuß ab. Im Falle einer Leptonendichte (Antileptonendichte) in der Größenordnung der Baryonendichte wird der Anteil der strange-Quarks unterdrückt (hoch). In der Hadronenphase tragen die strange-Baryonen bis zu 50% des Baryonenüberschusses. 相似文献
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29.
Elva Escobar Briones Erika Laura Estrada Santilln Pierre Legendre 《Deep Sea Research Part II: Topical Studies in Oceanography》2008,55(24-26):2679
The composition, density and community structure of the benthic macrofauna were investigated in sediments of the Campeche Canyon in the SW Gulf of Mexico. Total macrofaunal density ranged from 9466±2736 ind m−2 at the continental shelf station to 1550±195 ind m−2 in the canyon. Density values significantly diminished with distance from the coast and depth; only a few stations in the center of the canyon displayed larger density values (E-37 with 4666±1530 ind m−2, E-36 with 5791±642 ind m−2 and E-26 with 6925±2258 ind m−2). Densities were positively correlated to organic nitrogen in the sediment (r=0.82) and coarse silt (r=0.43), and negatively with depth (r=−0.74) and distance from the coast (r=−0.68). At all stations, the polychaete worms contributed most to the multi-species community structure. The nematodes and Foraminifera displayed their highest densities in the center of the canyon. The biomass values declined significantly with depth. We conclude that the macrofauna density and biomass changed in response to organic matter contents in the sediment, both with distance from the coast and with depth. 相似文献
30.
Molecular organic biomarkers together with trace element composition were investigated in sediments east of Barrow Canyon in the western Arctic Ocean to determine sources and recycling of organic carbon in a continuum from the shelf to the basin. Algal biomarkers (polyunsaturated and short-chain saturated fatty acids, 24-methylcholesta-5,24(28)-dien-3β-ol, dinosterol) highlight the substantial contribution of organic matter from water column and sea-ice primary productivity in shelf environments, while redox markers such as acid volatile sulfide (AVS), Mn, and Re indicate intense metabolism of this material leading to sediment anoxia. Shelf sediments also receive considerable inputs from terrestrial organic carbon, with biomarker composition suggesting the presence of multiple pools of terrestrial organic matter segregated by age/lability or hydrodynamic sorting. Sedimentary metabolism was not as intense in slope sediments as on the shelf; however, sufficient labile organic matter is present to create suboxic and anoxic conditions, at least intermittently, as organic matter is focused towards the slope. Basin sediments also showed evidence for episodic delivery of labile organic carbon inputs despite the strong physical controls of water depth and sea-ice cover. Principal components analysis of the lipid biomarker data was used to estimate fractions of preserved recalcitrant (of terrestrial origin) and labile (of marine origin) organic matter in the sediments, with ranges of 12–79%, 14–45%, and 37–66% found for the shelf, slope, and basin cores, respectively. On average, the relative preserved terrestrial organic matter in basin sediments was 56%, suggesting exchange of organic carbon between nearshore and basin environments in the western Arctic. 相似文献