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301.
To unravel the mystery of the relationship between evaporates, Ca–Cl brines and accumulations of oil and N2 in the basins of ancient cratons, their N2, CH4 and He concentration ratios, as well as the isotopic composition (δ15N, δ13C and 3He/4He) were compared within the Volga-Ural basin. The study allowed subsalt fluids from Volga-Ural Basin to divide into two genetic groups. The first one is found within the basin's platform area. It includes Ca–Cl brines, high-viscosity heavy oil, bitumen and N2, which has concentrations higher than that of CH4 and positive values of δ15N. The second one is tied to the edge of the platform, the Ural Foredeep and Peri-Caspian Depression. In this group, only the oil and gas reservoirs, which have more CH4 than N2, and possibly negative values of δ15N, were discovered. Interaction of gas components in compared fluids indicates great role of degassing in the formation of their composition. It is suggested that the fluids of the first group (N2 > CH4) is what remains, and the second group (N2 < CH4) is what is disappears from the rocks during their metamorphism and degassing.  相似文献   
302.
GNSS-R海洋遥感监测技术综述   总被引:2,自引:0,他引:2  
介绍了GNSS-R海洋遥感的发展过程、技术原理和理论模型,进一步研究了GNSS-R在海洋遥感各应用领域的主要研究内容,探讨了GNSS-R海洋测风、测高、海冰监测、溢油检测和移动目标探测的技术途径,概述了GNSS-R海洋遥感监测技术所涉及的反演理论和信息提取方法,并根据现有研究成果和海洋遥感的应用需要,提出今后需解决的关键技术和未来的发展方向。  相似文献   
303.
墨西哥湾“深水地平线”溢油事故处理研究进展   总被引:4,自引:0,他引:4  
2010年4月20日美国墨西哥湾"深水地平线"石油钻井平台发生爆炸,并引发大火,致使大量的原油(~500万桶)在深海(~1 500m)泄露,这场灾难造成了巨大的环境和经济损失,也对石油开采业的发展产生了负面影响。文中综述了此次事故溢出石油的总量,泄露速率以及测量相关数据中所涉及的技术及方法,对进一步研究溢油转移的趋势和转化过程具有指导意义。喷洒了6.6×106 L的消油剂,消油剂可以促使溢油的快速分散,同时也会给海洋生态系统造成一定的影响。该事故对墨西哥湾的植被和海洋生物有不同程度的影响,如沼泽植被、海水中的浮游动/植物、鱼类、贝类、珊瑚虫、迁徙鸟类,甚至是墨西哥湾大型底栖生物。此次溢油事故涉及各种不同的环境情况,为研究石油烃降解菌在溢油转移和降解过程中种群和群落的变化提供了一个独特的机会,消油剂处理过的溢油转化机理以及微生物降解过程中生物表面活性剂的产生与生物标志物以及微生物菌落的变化之间的关系,仍需要进一步的深入研究和探讨。  相似文献   
304.
利用溶胶凝胶法自制了碳纳米管和纳米二氧化钛的复合光催化剂,采用投射电子显微镜和X光衍射仪对粉体的粒径、物象、形貌和热稳定性等进行表征。通过研究光照条件、催化剂的投加量、油的初始浓度、催化剂制备的煅烧条件等因素,考察了自制碳纳米管和纳米二氧化钛的复合催化剂对降解模拟海洋柴油污染的海水去除率的影响。研究发现,在可见光照条件下,400℃煅烧2 h的复合催化剂,投加量为0.4 g/L、柴油的初始浓度为0.6 g/L、反应的光照时间为4 h时效果最好,去除率可达到67.65%。  相似文献   
305.
准噶尔盆地西北缘南部红车断裂带- 车排子凸起油气藏众多,原油物理化学性质和地球化学特征十分复杂,原油类型及其来源长期存在很大争议。本文在准噶尔盆地不同时代烃源岩生成原油典型地球化学特征与主要油源判识指标归纳总结的基础上,对红车断裂带- 车排子凸起原油地球化学特征和来源进行系统分析研究,将该区域原油分为五类,其中三类原油分别来源于二叠系湖相烃源岩、中—下侏罗统煤系烃源岩、古近系安集海河组湖相烃源岩,另外两类为混合原油,分别为来源于二叠系湖相烃源岩的生物降解稠油与中—下侏罗统煤系烃源岩生成的正常原油和古近系湖相烃源岩生成的正常原油的混合原油。红车断裂带石炭系—白垩系油藏原油主要来源于沙湾凹陷二叠系湖相烃源岩,车排子凸起东北部春风油田稠油来源于沙湾凹陷二叠系湖相烃源岩;车排子凸起东侧- 红车断裂带西侧新近系沙湾组油藏轻质原油来源于四棵树凹陷古近系湖相烃源岩;车排子凸起中部春光油田白垩系—古近系油藏稠油为二叠系来源稠油和侏罗系正常原油的混合原油,新近系沙湾组油藏稠油为二叠系来源稠油与新近系正常原油的混合原油;车排子凸起西部石炭系—古近系油藏轻质原油来源于四棵树凹陷中—下侏罗统煤系烃源岩,而新近系沙湾组油藏轻质原油来源于四棵树凹陷古近系湖相烃源岩。本文对准噶尔盆地西北缘南部地区油气藏成藏研究及区域油气勘探决策具有重要参考作用。  相似文献   
306.
Combined with the actual geological settings, tight oil is the oil that occurs in shale or tight reservoirs, which has permeability less than 1 mD and is interbedded with or close to shale, including tight dolomitic oil and shale oil. The Fengcheng area (FA), at the northwest margin of the Junggar Basin, northwest China, has made significant progress in the tight oil exploration of the Fengcheng (P1f) Formation recently, which indicates that the tight oil resources have good exploration prospects. Whereas the lack of recognition of hydrocarbon generation and expulsion characteristics of Permian P1f source rocks results in the misunderstanding of tight oil resource potential. Based on the comprehensive analysis of geological and geochemical characteristics of wells, seismic inversion, sedimentary facies, tectonic burial depth, etc., the characteristics of P1f source rocks were investigated, and the horizontal distributions of the following aspects were predicted: the thickness of source rocks, abundance and type of organic matter. And on this basis, an improved hydrocarbon generation potential methodology together with basin simulation techniques was applied to unravel the petroleum generation and expulsion characteristics of P1f source rocks in FA. Results show that the P1f source rocks distribute widely (up to 2039 km2), are thick (up to 260 m), have high total organic content (TOC, ranging from 0.15 to 4 wt%), are dominated by type II kerogen and have entered into low mature–mature stage. The modeling results indicate that the source rocks reached hydrocarbon generation threshold and hydrocarbon expulsion threshold at 0.5% Ro and 0.85% Ro and the comprehensive hydrocarbon expulsion efficiency was about 46%. The amount of generation and expulsion from the P1f source rocks was 31.85 × 108 and 15.31 × 108 t, respectively, with a residual amount of 16.54 × 108 t within the source rocks. Volumetrically, the geological resource of shale oil is up to 15.65 × 108 t. Small differences between the amounts calculated by the volumetric method compared with that by hydrocarbon generation potential methodology may be due to other oil accumulations present within interbedded sands associated with the oil shales. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
307.
Despite continued uncertainty about the physical realities and political, economic and social implications of peak oil, combined concerns about oil scarcity, climate change and globalisation has spawned an energetic relocalisation movement dedicated to achieving a comprehensive reduction in oil dependency through community-scale initiatives. This paper uses a discourse approach to examine the emergence, geographical spread and practices of the Transition Network, a UK-originated relocalisation movement now involving 186 local initiatives in the UK and other countries. We trace the movement’s drawing upon, and innovation from, discourses and techniques used by other grassroots environmental movements to promote a spatial representation of peak oil as an inevitable and geographically undiscriminating problem, and its use of addiction metaphors and participatory techniques to promote personal and community-scale energy descent initiatives as a viable and necessary alternative to globalisation. We also analyse the spatial representations and techniques used in the Network’s “rhizomic” spread across multiple localities around the world and embedding in communities where relocalisation initiatives are established. We conclude by examining the future challenges these spatial constructions of peak oil pose for the relocalisation movement.  相似文献   
308.
Mazen Labban 《Geoforum》2010,41(4):541-552
Relations between oil scarcity, production, investment, and price have become increasingly mediated and shaped by financial markets. Yet, the mediation of finance is absent in peak oil narratives, which posit a direct relation between the availability of oil in the ground and its price on the market. The orthodox critique of peak oil deconstructs its basis in geological limits only to reproduce the argument from scarcity and reverse the relationship between the price of oil and its availability on the market. Both narratives are formulated in physical space and do not account for the degree to which the oil market has become infused by the logic of finance. Critical political economy, on the other hand, demonstrates the extent to which finance has transformed capital accumulation, only to render material production somewhat irrelevant to the accumulation of capital. This is equally problematic, given oil companies’ continuing investment in production and reserve expansion. The relation between accumulation, investment, and production under finance needs to be examined rather than discarded. I argue that finance has emancipated the circulation of oil in the world market from its circulation in physical space, fragmenting the oil market into a physical and a financial component, but reintegrating both under the dominance of financial logic without transcending their duality and their differences. I explicate this relation by examining the circulation of oil in trade and investment under the dictates of finance to open questions on current theorizations of oil scarcity in relation to prices, markets, and investment.  相似文献   
309.
塔里木盆地英买力地区原油地球化学特征与族群划分   总被引:1,自引:0,他引:1  
塔里木盆地英买力地区油气成因复杂,采用多馏分、多组分化学成分分析及单体烃碳同位素分析途径,对该区海相、陆相油进行精细分析。结果表明,英买力油田主要有两大类油组,分别是南部YM2井区的海相油(I类)和北部YM7井区的陆相油(Ⅱ类),各自具有典型的海相油与陆相油的特征。进一步分析表明,两大油组内部仍有分异。将第二油组进一步分为两亚类,以中、古生界产层为主的正常黑油和重质油为一类(Ⅱa),以古近系为主的凝析油为另一类(Ⅱb)。两亚类原油正构烷烃单体烃同位素稍有差异,芳烃组成与分布具有显著差异。较之于Ⅱa原油,Ⅱb原油富含联苯系列与氧芴系列、不同类型芳烃系列中以低分子量同系物占绝对优势,其正构烷烃单体烃碳同位素更重,与相邻的羊塔克地区原油表现出一定的相似性,表明两者之间有一定的成因联系,前者可能为混源油,由位于库车坳陷中拜城凹陷提供两种陆相烃源岩。英买力地区陆相油并非以往确认的一种成因类型,可能至少由两套性质迥异的中生界烃源岩供烃。英买力地区第一类海相油(I类)尽管生物标志物特征相近,但分析原油的单体烃碳同位素具有显著差异,同样存在油气混源的可能。英买力地区海、陆相原油特征与成因的深入剖析,对于该区精细油源确认、油气成藏机制乃至油气资源评价具有重要意义。  相似文献   
310.
缝洞型油藏大尺度可视化水驱油物理模拟实验及机理   总被引:1,自引:0,他引:1  
缝洞型碳酸盐岩油藏由于其缝洞组合关系的复杂性,使得储层流体的渗流规律有别于常规油藏。根据某油田奥陶系缝洞型碳酸盐岩的实际情况设计制作了大尺度可视化物理模型,并按照现场实际设计了二注三采的实验井网及注采方案,以应用物理模拟实验来研究缝洞型碳酸盐岩油藏的开发特征及油井生产规律。结合实验结果,利用J.Cruz-Hernández建立的数学模型对生产数据进行拟合,以研究缝洞型碳酸盐岩油藏中流体的渗流机理,J.Cruz-Hernández数学模型中的空间系数和流动速度对采收率影响较大,提出模型的改进应考虑重力分异作用、溶洞比例等影响因素。  相似文献   
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