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991.
广西十万大山盆地下二叠统生物礁古油藏及隐伏礁预测 总被引:19,自引:3,他引:16
广西宁明县亭亮下二叠统茅口组生物礁古油藏,为十万大山盆地已暴露破坏的礁古油藏之一。该古油藏的含沥青储层主要分布于礁体的上部和顶部,含沥青礁灰岩厚达98m以上,礁储层次生溶孔的形成与分布主要受控于深埋有机溶剂作用,同时在空间上还与礁顶部古风化壳和不整合面密切相关,论文深入探讨了礁古油藏形成的主要成岩作用类型及其埋藏一构造发展史,有机质演化史及成岩孔隙演化史三者的配置关系和成藏机理,另据地震和电法资料 相似文献
992.
Analysis of reservoir water quality using fuzzy synthetic evaluation 总被引:12,自引:0,他引:12
R.-S. Lu S.-L. Lo J.-Y. Hu 《Stochastic Environmental Research and Risk Assessment (SERRA)》1999,13(5):327-336
A general methodology for fuzzy synthetic evaluation is developed and illustrated with a case study of trophic status assessment
for Fei-Tsui Reservoir in Taiwan. The historical data base was collected from the management agency of Fei-Tsui Reservoir
from 1987 to 1996. In fuzzy synthetic evaluation, the classification is determined by a matrix operation of the weighted vector
with the fuzzy evaluation matrix. After all individual membership functions of evaluated factors have been determined, the
fuzzy evaluation matrix can be established. The weighted vector is determined by the analytic hierarchy process method (AHP).
The results of this investigation show that the long-term change of water quality and the overturn phenomena cannot be observed
with the Carlson index from 1987 to 1992 but is expressed by fuzzy synthetic evaluation. Fuzzy synthetic evaluation is better
suited than the Carlson index to rating the trophic status of self-sustaining lakes. Interpretation of the results can provide
valuable information to decision makers and aid reservoir management. 相似文献
993.
山西沁水盆地中,南部现代构造应力场与煤储层物性关系之探讨 总被引:28,自引:2,他引:26
山西沁水盆地中、南部下二叠统山西组主煤储层现代构造应力场主应力差增大、煤储层渗透率梯度呈指数形式增长,煤储层压力梯度呈对数增长,这种规律主要受控于现代构造应力场应力方向与煤储层天然裂隙优势发育方向之间的相互关系,这两组方向对于煤储层来说近于平行,对煤储层顶板则表现为近于正交,由此导致主煤储层中天然裂隙处于相对拉张状态,而其顶板天然裂隙处于挤压状态,主应力 越大,相对拉张效应就越显著。基于这种规律和 相似文献
994.
为了解决广西岩溶石山区人畜饮水和农田用水问题 ,需对丰富的地下水资源进行详细勘查和合理开发 ,采取有效措施 ,就能实现岩溶石山区人民的脱贫目标。 相似文献
995.
Analysis of Difference Between Direct and Geodetic Mass Balance Measurements at South Cascade Glacier, Washington 总被引:2,自引:0,他引:2
Robert M. Krimmel 《Geografiska Annaler: Series A, Physical Geography》1999,81(4):653-658
Net mass balance has been measured since 1958 at South Cascade Glacier using the 'direct method,' e.g. area averages of snow gain and firn and ice loss at stakes. Analysis of cartographic vertical photography has allowed measurement of mass balance using the 'geodetic method' in 1970, 1975, 1977, 1979–80, and 1985–97. Water equivalent change as measured by these nearly independent methods should give similar results. During 1970–97, the direct method shows a cumulative balance of about −15 m, and the geodetic method shows a cumulative balance of about −22 m. The deviation between the two methods is fairly consistent, suggesting no gross errors in either, but rather a cumulative systematic error. It is suspected that the cumulative error is in the direct method because the geodetic method is based on a non-changing reference, the bedrock control, whereas the direct method is measured with reference to only the previous year's summer surface. Possible sources of mass loss that are missing from the direct method are basal melt, internal melt, and ablation on crevasse walls. Possible systematic measurement errors include under-estimation of the density of lost material, sinking stakes, or poorly represented areas. 相似文献
996.
997.
李旭 《地球科学与环境学报》1999,(Z1)
许多储集岩经蒸汽和热水处理后,可产生明显的软化作用。这种软化作用主要是由于白云石、高岭石和石英的部分破坏和生成蒙脱石。在这种情况下,软化作用是相当大的,直至足以引起储集岩中支撑裂隙的显著愈合,因而,能导致钻井产能的显著减少。已经发现把一些物质(RA) 添加到热液中,不仅能够防止岩石软化,而且能使岩石硬化。这一效果来源于岩石中原始粘土矿物的改变和新生矿物相的重结晶和重新取向 相似文献
998.
For the construction of the new Athens International Airport, it was imperative that a hill, obstructing air traffic, be lowered by approximately 40 m. Unfortunately, a fortified prehistoric settlement was situated on top of that hill. In order to carry out this task, it was required: (a) to produce a model of the site at a scale of 1;50; and (b) to monitor and document every single stone during the dismantling of the most important parts of the site, so that its rebuilding elsewhere and at a later time would be possible.
The Laboratory of Photogrammetry, National Technical University of Athens, undertook to provide the necessary metric data. By using low altitude aerial photographs from a helicopter, a specialized tripod and terrestrial photogrammetric techniques, the following products were created, all at a scale of 1;50: contour lines and DTM of the site; digital orthophotograph of the site; graphic drawing of the development of the exterior of the surrounding wall; and graphic drawings of the upper (initial) and the lower (last) levels of the parts to be removed. In this paper, both the fieldwork and the final products are presented and evaluated. 相似文献
The Laboratory of Photogrammetry, National Technical University of Athens, undertook to provide the necessary metric data. By using low altitude aerial photographs from a helicopter, a specialized tripod and terrestrial photogrammetric techniques, the following products were created, all at a scale of 1;50: contour lines and DTM of the site; digital orthophotograph of the site; graphic drawing of the development of the exterior of the surrounding wall; and graphic drawings of the upper (initial) and the lower (last) levels of the parts to be removed. In this paper, both the fieldwork and the final products are presented and evaluated. 相似文献
999.
1000.
热带和中纬太平洋海温异常对东北夏季低温冷害影响的诊断分析研究 总被引:19,自引:0,他引:19
利用1995~1997年东北地区23个测站的地面气温资料、1950~1996年太平洋地区月平均海温资料以及1980~1994年全球月平均风场资料,分析了东北夏季低温冷害的时空特征和变化规律,探讨了太平洋各区域的海温异常与低温冷害之间的可能联系及其影响机理。结果表明,用EOF分解得到的前三个特征向量(占总方差的84.28%)基本表示了东北夏季气温的变化,用这三个特征向量重建的气温距平场,存在着3~4年、6~8年和准16年的主周期,其中6~8年的主分量信号最强。在年代际尺度上,在1979年前后发生了由气温偏冷向偏暖的突变。热带西太平洋暖池(140°E~180°,10°S~10°N)是影响东北夏季气温的关键海域,那里前期冬季海表温度变化是预测东北夏季低温冷害的强信号。另一个关键海域是中纬西太平洋(130°E~180°,10~30°N),前期春季的海温变化也与东北夏季低温有较密切的联系。 相似文献