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521.
522.
The upper spontaneous potential produced by oil and gas accumulation is of a stable potential field, and its intensity is directly proportional to the content of the source and inversely proportional to the radius apart from the source. Theoretical research and practical results show that anomalies of spontaneous potential can indicate oil-bearing sandstone bodies and locate the areas of oil and gas accumulation. In oil areas which have fewer reservoir beds, the petroleum reservoir thickness can be predicted by determining the linear relationship between potential intensity and apparent equivalent thickness. In the Weixing (卫星) oilfield, which is devoid of sufficient reservoir beds, its apparent equivalent thickness can be predicted by the linear equation h= -0.19x+0.74. On the basis of geological research, we use the spontaneous potential method to predict the equivalent thickness, helping in the selection of the most appropriate drill sites to enhance the probability of successful well boring so as to serve the next round development of the oilfield. 相似文献
523.
524.
Observed pollutants are of both primary and secondary origins, influenced by local topography and meteorology. Identifying
sources and relative contribution often require vast detailed data collection and complicated models. This study applied a
statistical time series analysis to two selected pollution events, spring and fall, at two sites in northern Taiwan. Vector
moving average representations were used to quantitatively examine relationships among chemical pollutants and estimate their
lifetimes. Results from impulse responses show that wind direction change alters the characteristic of pollution observed
in opposite sites of Taipei City, from chemical dominant system to transport dominant one and vice versa. Chemicals are clearly
separated into photochemical pollutants and primary pollutants. Results pointed out that Taipei City is the major source of
photochemical smog, but not these primary pollutants. Derived chemical lifetimes at same location vary from 20% to four times
under different meteorological condition. Estimated concentrations of hydroxyl radical range between 2 to 8 × 107 cm−3. Photochemical pollutants are responsible for parts of PM10 collected in both station observed. Oxidation of SO2 is only important in PM10 observed at one station. This study provides a simpler tool to derive information usually from
complex models, therefore, is suitable as complement in decision-making process. 相似文献
525.
《国际泥沙研究》2020,35(5):516-526
Heavy metal (HM) pollution in sediment is a serious concern particularly in developing nations, warranting an extensive survey to understand the current situation and propose possible remedial measures. This paper compiles the data of HMs cadmium (Cd), iron (Fe), cobalt (Co), manganese (Mn), arsenic (As), lead (Pb), chromium (Cr), copper (Cu), zinc (Zn) and nickel (Ni) in aquatic sediment from India from 1979 to 2017. It was found that mean values of Cu, Co, Zn, Pb, As, and Cr in Indian sediment were high in comparison to the Australian Interim Sediment Quality Guidelines, World Surface Rock Average, and the Threshold Effect Level for freshwater ecosystems. Anthropogenic activities, lithogenic factors, and sand intrusion are the main factors associated with HM pollution as observed using cluster analysis and principal component analysis. The results of contamination indices indicate that HM contamination ranged from average to high, in the sediment. The ecological risk assessment results showed that 11% HMs present very high risk. The cancer risk, due to the high contents of Cd, As, and Cr the ingestion pathway, showed high risk of cancer through food/water contaminated with sediment. At source reduction of HMs in industrial effluents by effluent treatment plants, and plantation of phytoremediating rooted macrophytes in sediment may help in HM mitigation of the sediment. 相似文献
526.
沈丘盆地是中、新生代交错叠置盆地,具有地质结构复杂、断块发育、非均质性强、渗透性差别大、含油层系多、原油多源等特点,有一定油气前景,但勘探难度较大,不适用常规的勘探开发程序,下一步勘探应以小型断块油气藏和断块—岩性油气藏为主要类型,采用多学科综合研究、多因素综合考虑、多手段协同作战的综合勘探方法,在综合评价的基础上,优选有利区块实施滚动勘探与开发。 相似文献
527.
介绍了石油测井深度光电编码器测量系统的测量原理、系统组成以及电路分析,同时在对系统误差分析的基础上给出了具体校正方法。 相似文献
528.
塔里木盆地天然气运聚系统与运聚模式 总被引:7,自引:0,他引:7
对塔里木盆地东部地层压力结构和天然气性质差异的研究表明,塔里木盆地东部具有多个独立的天然气运聚系统。这些运聚系统具有流体封存箱的特征。天然气只能在运聚系统内部进行短距离的运移,不能进行大规模侧向运移。因此天然气藏的形成具有近源的特点。由于不同运聚系统特征的差异,塔里木盆地大致有三种天然气运聚模式。 相似文献
529.
扇三角洲沉积体系及其与油气聚集关系 总被引:23,自引:2,他引:21
扇三角洲沉积体系是断陷盆地中极为发育的一种沉积体系,主要由扇三角洲平原组合、扇三角洲前缘组合和前三角洲沉积构成,可识别出9种成因相。受沉积物供给速率、可容空间增长速率及盆缘断裂产状等因素控制可划分出退积型、加积型、前积型、陡坡型和缓坡型5种扇三角洲类型。位于扇三角洲平原的辫状分流河道砂体及其位于扇三角洲前缘的与之有成因联系的水下分流河口坝、洪水型重力流砂体等物性好,可以构成优质储层。含油性勘探成果亦证实各主力油层段平面上主要分布于扇三角洲前缘及分流间湾区,小部分位于扇三角洲平原区。受埋藏深度和成岩场的影响,不同地区、不同层位主力油层段的物性与岩性相关性各异。因此,应用沉积体系分布与油气聚集规律挖掘剩余油层及进行远景区预测是有效的与可行的。 相似文献
530.
百色盆地低熟油的地球化学特征及成因机制 总被引:2,自引:0,他引:2
对百色盆地几个典型低熟油进行了常规的有机地球化学分析,并重点以百-5井低熟油为对象,详细总结了饱和烃,芳烃生物标志物地球化学特征及其组合,结果表明陆生高等植物和微生物大量繁衍及其对高等植物的改造的贡献可能是形成百色盆地第三系低熟油的主要原因。 相似文献