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161.
鄂尔多斯盆地合水地区长6储层主要为长石岩屑砂岩,平均孔隙度8.68%,平均渗透率0.15×10-3μm2,属于典型的低孔特低渗透储层。储层经历了压实作用、胶结作用、交代作用、溶蚀作用的改造,目前处于晚成岩阶段A期。在成岩作用研究的基础上,通过大量的岩心观察、薄片鉴定、扫描电镜等方法及测井曲线特征研究,进行了单井成岩相分析,进而编制成岩相平面分布图。将研究区辫状河三角洲前缘砂体划分出4个成岩相带:压实相、碳酸盐胶结相、绿泥石膜剩余孔相和绿泥石膜剩余孔—长石溶蚀相。其中,有利储层主要分布在主砂体的绿泥石膜剩余孔相和绿泥石膜剩余孔—长石溶蚀成岩相带上。根据试油资料,处于该有利相带的井一般日产油大于10t/d。 相似文献
162.
南祁连盆地在二叠纪时期处于稳定的海陆交互相沉积,盆地南部主要为海相沉积,北部为陆相沉积,碎屑岩比较发育。地球化学主量元素、微量元素分析结果表明,中二叠统勒门沟组、上二叠统诺音河群以及北部陆相二叠系的源岩构造背景均十分复杂,但以活动大陆边缘为主。结合区域地质构造背景判断南祁连盆地二叠纪沉积物源可能为其以北的中祁连—陇西地块的前寒武纪变质结晶岩系及花岗岩。 相似文献
163.
164.
In this study, rapid topographic changes and increased erosion rates caused by massive slope failures in a glacierized and permafrost‐affected high‐mountain face were investigated with respect to the current climatic change. The study was conducted at one of the highest periglacial rock faces in the European Alps, the east face of Monte Rosa, Italy. Pronounced changes in ice cover and repeated rock and ice avalanche events have been documented in this rock wall since around 1990. The performed multi‐temporal comparison of high‐resolution digital terrain models (DTMs) complemented by detailed analyses of repeat photography represents a unique assessment of topographic changes and slope failures over half a century and reveals a total volume loss in bedrock and steep glaciers in the central part of the face of around 25 × 106 m3 between 1988 and 2007. The high rock and ice avalanche activity translates into an increase in erosion rates of about one order of magnitude during recent decades. The study indicates that changes in atmospheric temperatures and connected changes in ice cover can induce slope destabilization in high‐mountain faces. Analyses of temperature data show that the start of the intense mass movement activity coincided with increased mean annual temperatures in the region around 1990. However, once triggered, mass movement activity seems to be able to proceed in a self‐reinforcing cycle, whereby single mass movement events might be strongly influenced by short‐term extreme temperature events. The investigations suggest a strong stability coupling between steep glaciers and underlying bedrock, as most bedrock instabilities are located in areas where surface ice has disappeared recently and the failure zones are frequently spatially correlated and often develop from lower altitudes progressively upwards. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
165.
珠三角是我国港口布局的重要区域,悠久的发展历史和独特的政治环境,区域港口体系发展具有独特的模式和过程。在详细梳理不同阶段港口体系发展阶段和特征的基础上,从长时间序列构建了珠三角地区港口体系演化模型。该模型与西方发达国家以及殖民地国家的港口体系演化具有一定的差异。珠三角港口体系具有港口体系波动特征,不同于西方国家模型中只有单一集中化和分散化发展趋势的描述;其次,珠三角港口体系发展模型的起始阶段为单极化发展阶段,而非西方国家模型中的均衡化发展阶段;最后珠三角港口体系发展模型增加了对枢纽港口空间位置转移的描述。 相似文献
166.
基于对我国879个城市新区的统计比较,分析了我国目前存在的市场型、开发区型和政区型3种城市新区开发管理模式,以及行政区内部整合、跨行政区整合、开发区设立行政区、行政区-开发区合署、行政区设立新区、新设行政新区等空间组织方式,并且不同的管理模式与空间组织形式存在着差异性、演化性和适用性的特点,城市新区的发展必须根据发展阶段、地域特征、功能形式等选择合适的组织管理形式. 相似文献
167.
Mathias Trachsel Bjørn Christian Kvisvik Pål Ringkjøb Nielsen Jostein Bakke Atle Nesje 《Journal of Paleolimnology》2013,50(4):583-592
Reflectance spectroscopy in the visible spectrum (VIS-RS) is a method that has been successfully applied for inferring organic content of sediments. In this study, we test the applicability of VIS-RS to lake sediments in Norway. On the one hand we use conventional, established algorithms for inferring organic content of sediments, on the other hand we test the potential of multivariate calibration techniques to infer organic content. For absolute quantification of organic content, conventional Cb>org b> measurements are needed when using conventional algorithms as well as when employing multivariate calibration techniques. Both, conventional algorithms and multivariate calibrations, result in estimates of organic content closely mirroring loss-on-ignition measurements. When using multivariate calibration techniques, a conventional Cb>org b> measurement every 5 cm is sufficient to obtain estimates of organic matter that are more accurate than those obtained by means of conventional algorithms. Therefore, the potential of multivariate calibration techniques and VIS-RS to substitute measurements of more time consuming and costly sediment parameters (e.g. clay minerals) should be tested. 相似文献
168.
The experimental studies of the wave breaking effects on freak wave generation are presented within a finite-depth random wave train in a laboratory wave tank. The main attention is paid to the abnormal index,AI=Hmax/Hs,being used to characterize the freak waves,and the changes of the coefficient due to wave breaking. The results show that the occurrence probability of freak wave events in non-breaking waves is much larger than that in breaking waves and such occurrence in deep water is larger than that in ... 相似文献
169.
The effects of various types of waves on vertical plane turbulent jets are studied numerically in the paper. A three-dimensional numerical model in σ-coordinate is developed to study these problems by use of large eddy simulation method. Turbulence is modeled by a dynamic coherent eddy model. Numerical results including the distribution of velocity,the decay law of the mean velocity along axis,the turbulent Reynolds stresses and the volume flux per unit width without wave,in the first-order Stokes waves,in ... 相似文献
170.
基于E-FAST全局定量敏感性分析方法的思想,提出一个针对分布式物理水文模型——流溪河模型的参数敏感性分析方法,包括参数简化及取值范围确定、参数采样及采样次数的确定、敏感性评价指标的选取、参数敏感度计算4个部分.针对我国4个不同规模的流域(黄龙带水库流域、流溪河水库流域、长湖水库流域和新安江水库流域)开展了分布式物理水文模型参数敏感性分析,并采用4种不同的评价函数进行了对比计算.结果表明,流溪河模型饱和含水率和田间持水率是高度敏感参数,饱和水力传导率、土壤层厚度、土壤特性系数、边坡和河道糙率为敏感参数,其他参数为不敏感参数. 相似文献