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231.
东辛油田沙三中亚段发育大量与三角洲前缘滑塌相伴生的坡移浊积扇、滑塌浊积扇、远源浊积岩以及洪水成因的水下碎屑流,发育岩性油藏及岩性-构造油藏。纵向上,湖退体系域早期准层序组PS7~PS5是最主要的油气富集层位,其次为湖侵体系域PS8;平面上,各准层序组西部油气富集程度好于东部,含油储层主要为滑塌浊积扇及部分远源浊积岩,其次为坡移浊积扇。油气分布主要受宏观沉积相带、构造、微观储集物性和成岩作用等多种因素控制,距油源远近控制油藏纵向有利层位,砂体成因类型控制着平面有利区带。  相似文献   
232.
卫星遥感技术在油气勘探中的应用   总被引:4,自引:0,他引:4  
卫星遥感技术在油气勘探中的应用日趋广泛,尤其在含油气盆地构造研究和烃类微渗漏检测方面取得了显著进展。根据目前国内外的研究资料,结合中国南方的遥感实例,介绍了盆地的遥感构造特征,遥感解译的方法、步骤和实际效果。阐述了遥感技术在油气藏烃类微渗漏勘探中的检测原理、方法和应用。现状表明,高光谱遥感与智能计算将在油气勘探中发挥重要作用。  相似文献   
233.
柴达木盆地北缘断裂构造分形特征与油气分布关系研究   总被引:15,自引:5,他引:15  
本文应用分形几何理论对柴达木盆地北缘断裂体系的分布进行了定量研究,在研究标定尺度范围内,该区断裂体系的平面分布具有良好的统计自相似性和分形特征,在双对数坐标系中,用最小二乘法进行直线拟合的相关系数平方(R2)均在0.97以上。该区4个已知油气田断裂构造的分维数D值均大于1.3,明显高于整个区域内4个反射层的断层分维数(平均D=1.218)。可以认为断裂构造的分维值大于1.3的部位是该区油气聚集分布的有利区。断裂体系分数维值越大的地区,有利于油气藏的分布,其单位面积内的油气地质储量越高。  相似文献   
234.
鄂尔多斯盆地油气地质的古地磁研究   总被引:3,自引:0,他引:3  
黄华芳  杨占龙 《沉积学报》1995,13(4):161-168
古地磁研究结果表明,鄂尔多斯盆地寒武纪-早中奥陶世位于北纬14°~20°的古纬度区内,气候温暖潮湿,其南部和北部边缘的滨浅海相地层中可能富含生物有机质,是寻找该时期油气资源的有利地区;晚奥陶世-早石炭世,它可能经历了大规模的南北向水平构造迁移;晚石炭世-二叠纪,盆地处于北纬20°左右地区,广泛发育的湖沼相沉积地层是煤成油、气的主要源岩层;三叠纪-侏罗纪,它位于北纬24°~31°,干湿交替的气候环境和差异构造旋转作用,为盆地边缘的油气形成和聚集创造了良好条件,因此有希望找到更多的中生代油气资源。  相似文献   
235.
本文通过对LandsatTM图像和NOAAAVHRR图像进行特殊的处理,将石油污染区与周围海水区别开来,利用Landsat卫星精度和NOAA卫星时相的优势,可以确定污染面积、扩散方向和扩散速度。  相似文献   
236.
本文提出了一种利用多级BP神经网络进行石油测井信号分类的新方法.介绍了用多级BP网络处理测井信号的分类器算法和网络结构,并给出了针对理论模拟信号的分类结果及针对实际模型井信号的分类结果,其正确率可达90%以上.  相似文献   
237.
Review of behaviour of oil in freezing environments   总被引:2,自引:0,他引:2  
The current knowledge of the physical fate and behaviour of crude oil and petroleum products spilled in Arctic situations is reviewed. The fate and final deposition of oil in marine conditions is presented as based on the extant literature.

Spreading models were evaluated for oil on ice, under ice, in snow, in brash ice, and between blocks of ice. Models of oil transport under sheet and broken ice were considered, both for sea and river conditions. The ability of ice sheets to trap oil is discussed in relation to oil storage capacity. The effects of oil on a growing ice sheet were examined, both in terms of ice formation and the thermal effects of oil inclusions in ice. The migration of oil through ice was reviewed, focussing primarily on the movement through brine channels. The effects of oil on the surface of ice were considered, with emphasis on the effects of surface pools on ice melt. Similar consideration was given to the effects of oil on snow on the surface of ice.

The few quantitative studies of oil in open and dynamic ice conditions are reviewed. Observations of intentional small-scale spills in leads and ice fields are reviewed and compared with observations from real spills. The conditions under which “oil pumping” from leads occurs were quantified. The most common ultimate fate of oil in an ice field is to be released onto the water surface.  相似文献   

238.
The concentrations of Al, Fe, Mn, Zn, Cu, Pb, Ni, Cr, Ba, V, Sn and As in offshore bottom sediments from the Bacia de Campos oil field, SE Brazil, were measured at the beginning and at 7 months after completion of the drilling operation. Concentrations of Al, Fe, Ba, Cr, Ni and Zn were significantly higher closer to the drilling site compared to stations far from the site. Average concentrations of Al, Cu, and in particular of Ni, were significantly higher at the end of the drilling operation than at the beginning. Comparison between drilling area sediments with control sediments of the continental platform, however, showed no significant difference in trace metal concentrations. Under the operation conditions of this drilling event, the results show that while changes in some trace metal concentrations do occur during drilling operations, they are not significantly large to be distinguished from natural variability of the local background concentrations.  相似文献   
239.
Benthic faunal structure and hydrocarbon concentrations in sediments were examined annually for 10 years (1989-1998) in Port Valdez, Alaska, where a near-bottom permitted discharge of treated tanker ballast waters containing residual petroleum has occurred since 1977. Measured concentrations of hydrocarbons in sediments near the discharge showed detectable increases in concentration, but on only one occasion were these increases either to levels exceeding ecotoxicological thresholds (Effects-Range Low, ER-L) or associated with alterations in the benthic community. Changes in faunal structure indicating disturbance were observed at one station near the discharge from 1995 to 1997 and were apparent as increased numbers of opportunistic taxa and anomalous trends in abundance and diversity. Minimum-effect (ME) hypotheses provided evidence of negligible to small effects on benthic infauna from disposal of treated ballast water. ME hypotheses have the potential to assist both researchers and managers by providing a tool to relate scientific results to ecological importance and decision criteria.  相似文献   
240.
To reduce rehabilitation time and improve survival, a practical, objective test is needed to determine if marine birds are contaminated with oil before they enter captivity. The RaPID Assays and EnviroGard immunoassays for detection of polycyclic aromatic hydrocarbons (PAHs) in soil were evaluated for their ability to detect petroleum on feather samples from 30 intermediate fuel oil contaminated and 30 uncontaminated common murres (Uria aalge). Sensitivity, specificity, positive and negative predictive value, precision, and time required to run each assay were determined. The RaPID Assays was 96.7% sensitive and specific, while the EnviroGard assay was 93.3% sensitive, and 90.0% specific. Sensitivity decreased at higher dilutions for both assays. Intra-replicate variation was less than 20%. Our evaluation showed that these immunoassays are rapid and cost-effective methods for detecting oil-contamination on the plumage of seabirds, with the EnviroGard assay being more practical in most oil spill response situations due to ease of use and rapidity of results.  相似文献   
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