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101.
世界主要深水含油气盆地烃源岩特征   总被引:1,自引:1,他引:1  
对墨西哥湾、巴西东部大陆边缘、西非被动大陆边缘、澳大利亚西北陆架、挪威中部陆架、南海等六个地区的22个深水含油气盆地烃源岩特征(主力烃源岩形成的时代、构造背景、沉积环境、类型、地球学化指标等)的综合研究结果表明,世界深水含油气盆地主力烃源岩主要集中在白垩系,其次为第三系和侏罗系;裂谷期烃源岩占绝对优势,其次为被动陆缘期...  相似文献   
102.
Polarimetric synthetic aperture radar(SAR) oil spill detection parameters conformity coefficient(μ), Muller matrix parameters(|C|, B_0), the eigenvalues of simplified coherency matrix(λ_(nos)) and the influence of SAR observing parameters, ocean environment and noise level are investigated. Radarsat-2 data are used to make systematic analysis of polarimetric parameters for different incidences, wind speeds, noise levels and the ocean phenomena(oil slick and look likes). The influence of the SAR observing parameters, the ocean environment and the noise level on the typical polarimetric SAR parameter conformity coefficient has been analyzed. The results indicate that conformity coefficient cannot be simply used for oil spill detection, which represents the image signal to the noise level to some extent. When the signals are below the noise level for the oil slick and the look likes, the conformity coefficients are negative; while the signals above the noise level corresponds to positive conformity coefficients. For dark patches(low wind and biogenic slick) with the signal below the noise,polarization features such as conformity coefficient cannot separate them with oil slick. For the signal above the noise, the oil slick, the look likes(low wind and biogenic slick) and clean sea all have positive conformity coefficients, among which, the oil slick has the smallest conformity coefficient, the look likes the second, and the clean sea the largest value. For polarimetric SAR data oil spill detection, the noise plays a significant role. So the polarimetric SAR data oil spill detection should be carried out on the basis of noise consideration.  相似文献   
103.
测井曲线在地层基准面旋回划分中的应用   总被引:5,自引:0,他引:5       下载免费PDF全文
利用视电阻率测井曲线的周期性对渤南海油田沙三段中上部地层进行地层基准面旋回的划分对比后发现:该旋回界面与地层基准面由上升到下降期间可容纳空间单向增加的极限位置基本一致;地层基准面旋回的划分与测井分析结合可以进行储层。特别是高渗透储层预测。  相似文献   
104.
Large amounts of gas hydrate are distributed in the northern slope of the South China Sea, which is a potential threat of methane leakage. Aerobic methane oxidation by methanotrophs, significant methane biotransformation that occurs in sediment surface and water column, can effectively reduce atmospheric emission of hydrate-decomposed methane. To identify active aerobic methanotrophs and their methane oxidation potential in sediments from the Shenhu Area in the South China Sea, multi-day enrichm...  相似文献   
105.
随着石油资源可用量的不断减少,页岩气、油页岩、油砂与稠油作为一种新能源,近年来备受人们的重视。山东省存在着丰富的油页岩资源。近年来笔者通过收集前人相关资料、野外地质填图、钻探编录、典型矿区考察、关键样品化验分析等手段对其进行了初步研究,初步认识了山东地区油页岩的资源特征及其形成环境,对未来山东地区油页岩矿的预测及潜力的评价具有一定的指导与借鉴作用。  相似文献   
106.
Cutting and removal of oil-impacted marsh plants are still used worldwide as a clean-up and recovery technique. To experimentally test the efficacy of cutting and removing marsh plants under subtropical conditions, we simulated an oil spill (Bunker MF-180) in Spartina alterniflora marshes and compared the responses of plant height, biomass, density of culms and number of flowering plants in high and low energy areas in Paranaguá Bay (S Brazil) for about 9 months. Cutting and removal were inefficient in promoting or accelerating the recovery of the impacted areas. Cut or uncut impacted marshes fully recovered within 6 months, both in low and high energy areas. Plant cutting should be practiced only when there is an effective risk of contamination of groundwater near urban areas, when obvious aesthetical issues are involved in areas of touristic interest or when there are real short-term conservation risks to threatened species.  相似文献   
107.
The objective of this study is to determine numerical estimations of seismic amplifications of waves traveling from offshore to shore considering the effect of sea floor configurations. According to the Boundary Element Method, boundary elements were used to irradiate waves and density force can be determined for each element. From this hypothesis, Huygens’ Principle is implemented since diffracted waves are constructed at the boundary from which they are radiated and this is equivalent to Somigliana's theorem. Application of boundary conditions leads to determine a system of integral equations of Fredholm type of second kind, which is solved by the Gaussian method. Various numerical models were analyzed, a first one was used to validate the proposed formulation and some other models were used to show various ideal sea floor configurations to estimate seismic amplifications. Once the formulation was validated, basic slope configurations were studied for estimating spectra of seismic amplifications for various sea floor materials. In general terms, compressional waves (P-waves) can produce seismic amplifications of the incident wave in the order of 2–5. On the other hand, distortional waves (S-waves) can produce amplifications up to 5.5 times the incident wave. A relevant finding is that the highest seismic amplifications due to an offshore earthquake are always located near the shore-line and not offshore despite the seafloor configuration.  相似文献   
108.
Thermal history, petroleum system, structural, and tectonic constraints are reviewed and integrated in order to derive a new conceptual model for the Norman Wells oil field, and a new play type for tectonically active foreland regions. The thermal history recorded by Devonian rocks suggests that source rocks experienced peak thermal conditions in the Triassic–Jurassic, during which time oil was likely generated. After initial oil generation and expulsion, the Canol Formation oil shale retained a certain fraction of hydrocarbons. The shallow reservoir (650–350 m) is a Devonian carbonate bank overlain by the Canol Formation and resides within a hanging wall block of the Norman Range thrust fault. Both reservoir and source rocks are naturally fractured and have produced high API non-biodegraded oil. Thrust faults in the region formed after the Paleocene, and a structural cross-section of the field shows that the source and reservoir rocks at Norman Wells have been exhumed by over 1 km since then.The key proposition of the exhumation model is that as Canol Formation rocks underwent thrust-driven exhumation, they crossed a ductile–brittle transition zone and dip-oriented fractures formed sympathetic to the thrust fault. The combination of pore overpressure and new dip-directed subvertical fractures liberated oil from the Canol Formation and allowed for up-dip oil migration. Reservoir rocks were similarly fractured and improved permeability enhanced charging and pooling of oil. GPS and seismicity data indicate that strain transfer across the northern Cordillera is a response to accretion of the Yakutat terrane along the northern Pacific margin of North America, which is also the probable driving force for foreland shortening and rock exhumation at Norman Wells.  相似文献   
109.
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   
110.
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   
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