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991.
Reservoir geochemistry of South Pass 61 Field, Gulf of Mexico: compositional heterogeneities reflecting filling history and biodegradation 总被引:1,自引:0,他引:1
A.G. Holba L.I.P. Dzou J.J. Hickey S.G. Franks S.J. May T. Lenney 《Organic Geochemistry》1996,24(12):1179-1198
Cluster analysis of GC data for gasoline and mid-range hydrocarbon ratios from fifty-one South Pass 61 Field oils reveals geochemically similar oil clusters corresponding to geographically coherent groups. Insight into the groupings is obtained from examination of indicators of geochemical processes, e.g., anaerobic biodegradation, aerobic biodegradation and extensive remigration of light ends. Six duplicate samples collected in 1986 and 1992 as well as replicate runs on a single sample showed excellent analytical reproducibility.Subtle but consistent differences in both gasoline and oil-range hydrocarbon maturity indicators are observed between the east, west, and far west flanks of the field, suggesting filling of different segments of the reservoir from different kitchens at slightly different stages of thermal maturity or with slightly different chemical character. The west flank of the salt dome was charged with slightly more thermally mature petroleum than the east flank. The stratigraphically oldest and deepest sand on the far west flank has received the most mature petroleum. Different fluid contacts and GORs are observed in different sands and different fault blocks. The stacked pay geometry of the field and widespread faulting have led to considerable remigration of gas and condensate as observed in other fields in the Gulf of Mexico (Thompson, 1987).Biodegradation varies in severity with depth and reservoir zone, but is frequently overprinted by remigration of light end hydrocarbons. Anaerobic biodegradation by sulfate-reducing bacteria is probably the cause of light to moderate alteration in intermediate depth Pliocene sands which are hydraulically connected to the salt dome (with dissolution of anhydrite from the salt dome providing the sulfate). Widespread late pyrite formation in reservoir sandstones is inferred to represent the ultimate sink for reduced sulfur from sulfate reduction during oil biodegradation. Co-produced water compositions suggest no oxygenated freshwater infusion. 相似文献
992.
David H. Kaplan 《The Professional geographer》1996,48(4):356-367
Mortgage activity has commonly been measured with two variables: the volume of loans and the success rate of applications. I argue that these measurements represent distinct portions of the overall mortgage market and correspond to different social, racial, and economic attributes. Using Home Mortgage Disclosure Act data for 1991 and 1992 in the Minneapolis-St. Paul metropolitan area, I compare a variable measuring the percentage of loan applications denied with a variable measuring the number of loans per 1,000 housing units. I find that these two variables display disparate spatial patterns, that they are associated with different census tract characteristics, and that they correspond to separate dimensions of social geography. These differences suggest that the evaluation of bank performance in meeting fair housing objectives depends on how this performance is measured. Both measurements are useful, but care must be taken in their application. 相似文献
993.
与野外BRDF实验相比,室内实验更容易控制,具有无风、无云、光源固定和可全方位重复观测等优点,获取的反射率数据和测量的植被结构数据的精度要较野外测量的高,可用于BRDF模型验证及反演试验。 相似文献
994.
995.
996.
Ma Zongjin Zhang Peizhen Hong Hanjin and Gao Xianglin Institute of Geology SSB Beijing China 《中国地震研究》1997,(1)
Although great-progress has been made in the earth sciences,some fundamental problems of geodynamics remain unsolved.They are concerned with the whole earth as well as regional tectonics,such as the west Pacific and Qinghai-Xizhang plateau.The new generation of earth observation by space-based measurement will contribute to solving these problems of geodynamics.In this regard,some specific plans about application of these techniques are suggested in this paper. 相似文献
997.
Annotated bibliography of methodology for assessment of undiscovered oil and gas resources 总被引:1,自引:0,他引:1
Ronald R. Charpentier Gordon L. Dolton Gregory F. Ulmishek 《Natural Resources Research》1995,4(2):154-186
An annotated bibliography of methodology of assessment of undiscovered oil and gas resources is presented as a useful reference for those engaged in resource assessment. The articles that are included deal only with quantitative assessment of undiscovered or inferred resources. the articles in this bibliography are classified largely according to the major assessment method that was applied in each situation. Major assessment methods include areal and volumetric yield methods, field size distributions, historical extrapolation, deposit modeling, organic geochemical mass balance methods, and direct expert assessment. Other categories include mathematical tools, reserve growth/confirmation, quantitative characterization of undiscovered resources, and general topics. For the purpose of future updates, we solicit contributions of articles that may have been missed in the preparation of this bibliography. 相似文献
998.
James M. Roberts Andrew O. Langford Paul D. Goldan Fred C. Fehsenfeld 《Journal of Atmospheric Chemistry》1988,7(2):137-152
The applicability of the tungsten oxide denuder tube technique for the measurement of ammonia in the rural troposphere was investigated. The technique is based on selective chemisorption of NH3 from a gas stream, thermal desorption, conversion to NO, and analysis by NO–O3 chemiluminescence. Nitric acid, which is also collected and desorbed as NO, was distinguished from NH3 by differences in desorption temperature. Substituted amines were also collected, but desorbed at a slightly lower temperature than NH3 in dry air. At high relative humidities, alkylamines may be hydrolyzed to NH3 on the denuder surface and hence detected as NH3. Overheating of the denuder tube during the temperature-programmed desorption was found to cause significant irreversible degradation of system performance.The technique was used to measure NH3 mixing ratios at two rural locations in the United States. At a mountain site in Colorado during the winter of 1984, the average NH3 mixing ratio was 0.20 ppbv (=0.08 ppbv). At an isolated coastal site in northern California during the spring of 1985, the average NH3 mixing ratio was 0.36 ppbv (=0.17 ppbv). Correlations of the latter measurements with wind direction and NO
x
level suggest that the NH3 mixing ratio in Pacific marine air at 40°N is <-0.25 ppbv. 相似文献
999.
1000.
本文讨论了3cm天气雷达在兰州地区定量测量降水及其精度;分析了不同降水类型和衰减等对测量的影响;讨论了地面雨量计订正雷达测量值的方法和效果。 相似文献