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51.
Landslides in Jordan have caused numerous problems during the past 40 years. The most critical slides occurred during the period of 1991/1992 after exceptional heavy rain and snowfall. Many disastrous landslides occurred along the newly reconstructed international highway that links Amman, Jerash and Irbid. Causes for these slides are attributed mainly to the lack of a comprehensive overview and geotechnical understanding of the problem.Many investigators have been interested in this problem of finding an adequate solution to such landslides in Jordan either by using theoretical analysis or by using computer software to solve the slope instability problems. A detailed study was conducted at the Jordan University of Science and Technology to investigate the potential causes and measures for this problem. Seven landslides along the mountainous section of this international highway were reviewed. One of these landslides was thoroughly investigated using a three-dimensional computer program called JUST-SLOPE introduced at the Jordan University of Science and Technology campus. Results of this study indicate that landslides at this site could have been predicted had this technique been applied prior to the occurrence of this slide.  相似文献   
52.
塔里木盆地卫星重力异常与油气资源的相关性研究   总被引:2,自引:0,他引:2  
张健  周国藩 《地球科学》1997,22(6):643-647
利用中国地区360阶局部重力场模型IGG93E,计算出不同阶窗的卫星重力异常,然后利用Molodensky单层密度积分方程将卫星重力转化为分层面密度异常,结合其他地球物理资料,分析并探讨了塔里木盆地油气资源与卫星重力异常的相关性。研究表明:塔里木盆地油气资源分布与101-180阶卫星分同密度异常图中负密度异常带关系密切。而181-360阶卫重分层面异常图则对盆地内生油、储油的坳陷、隆起等构造有较9  相似文献   
53.
塔中地区主要受塔中Ⅰ号、Ⅱ号及Ⅲ号三条大断层控制 ,形成巨型复式背斜 ,隆起高部位地层遭受了强烈的风化剥蚀。背斜之上 ,断裂和局部构造发育。可划分出两个主要成藏期 :第Ⅰ成藏期为寒武系—下奥陶统烃源岩成熟生烃运移期 ,生排烃高峰为志留纪 ;第Ⅱ成藏期为中—上奥陶统烃源岩在燕山期—喜马拉雅期成熟生烃运聚。第Ⅰ成藏期形成的油藏有两个特征 :在塔中Ⅰ号断裂带、北部斜坡带油气注入奥陶系及志留系圈闭中 ,形成原生油气藏 ;构造高部位 (如中央断垒带 )的油气藏在后期构造运动中遭受破坏。第Ⅱ成藏期形成的油藏可分为两类 :对早期油藏的再次充注 ;聚集形成新油藏。塔中地区的油气运移通道主要有断裂和不整合面 ,油气的分布也主要受断裂和不整合面所控制。塔中Ⅰ号构造带和北部斜坡带是较为有利的勘探区带  相似文献   
54.
The absolute amounts and relative distributions of neutral nitrogen compounds in the Tabei oilfield (e. G. Blocks Ln1-Ln1 1) showed remarkable migration fractionation in the vertical direction. From Ordovician reservoirs (O) to oil legs TⅢ and T Ⅰ of Triassic reservoirs in blocks LN1-LN11, the concentrations of [a] [c] decreased from 1. 59μg/g, 0.49μg/g to 0.17 μg/g (oil). The ratios of various alkylcarbazole isomers, such as 1,8-dimethylcarbazole/nitrogenpartially shielded isomers and 1,8-dimethylcarbazole/nitrogen-exposed isomers, were adopted as the indicators of petroleum migration. The ratios increased from 0.13, 0.20 to 0.67 and from going from the south to the north of the Tabei oilfield, the absolute concentrations of neutral nitrogen compounds decreased drastically, and the nitrogen-shielded isomers were enriched relative to nitrogen-exposed isomers and nitrogen-partially shielded isomers. Crude oils in the Tabei oilfield migrated laterally from the Jilake structure to the Sangtamu fault uplift and Lunnan fault uplift, and crude oils in the same fault uplift migrated and remigrated vertically from Ordovician reservoirs, to oil legs TⅢ to TⅠ of Triassic reservoirs.  相似文献   
55.
通渝隧道围岩变形的神经网络预测   总被引:4,自引:0,他引:4  
隧道新奥法施工中 ,常以围岩变形量作为评判围岩稳定性和支护结构经济合理性的重要指标。公路隧道围岩变形量是随时间而变化的数据序列 ,因而可以建立一些实时跟踪预测模型和方法。根据通渝隧道围岩拱顶下沉位移变形的特性 ,采用神经网络技术来预测其变形量 ,结果表明该方法简易、有效  相似文献   
56.
The west Kunlun fold-thrust belt (WKFTB) and the Altun fold-thrust belt (AFTB) are respectively located in the southern margin of the Tarim basin, NW China. The analyses of typical structures and regional dynamics of the fold-thrust belts reveal their different structural and petroleum features and mechanisms. WKFTB differs from AFTB by abundant fault-related folds and triangles zones, and was formed by northward extrusion of the west Kunlun orogen. AFTB was affected synchronously by northward extrusion of the Altun orogen and the sinistral strike-slipping of the Altun Fault, so it is characterized by the minor scale and the monotonous structural styles. The Aqike anticline and the Aqike fault, of which the strikes are orthogonal to the strike of the fold-thrust belts, are regarded as the adjustive structures between both of the fold-thrust belts. The oil-gas pools of WKFTB develop mainly in the faulted-related anticline traps, but the oil-gas pools of AFTB develop mainly in the low fault-block and anticlines traps related with the paleo-uplifts. There are different exploration countermeasures for both of the fold-thrust belts.  相似文献   
57.
The Tarim Basin is a typical superimposed basin in which there have occurred multiphase adjustment and destruction of the reservoirs. The widely distributed asphaltic sandstones of the Silurian are the very product after destruction of the reservoirs. Studies show that the Silurian asphaltic sandstones distributed in both the middle and western parts on the basin are controlled chiefly by the Caledonian oil source area and by the Tazhong, Tabei and Bachu uplifts, whereas the distribution of the asphaltic sandstones on local structural belts is controlled by the reservoir's sedimentary system. Vertically, most of the asphaltic sandstones are under the regional caprock of red mudstones and the upper sandstone section of compact lithology. Due to the difference of hydrocarbon destruction in the early stage and the influence of hydrocarbon recharge in the late stage, the asphaltic sandstones and oil-bearing sandstones in the Tazhong area can be vertically divided into the upper and lower sections and they have an interactive distribution relationship as well. Asphaltic sandstones exist not only in intergranular pores but also inside the grains of sand and between the crevices, proving the destruction of early reservoirs due to uplifting. The existence of asphaltic sandstones over a large area reveals that the large-scale migration and accumulation and the subsequent destruction of hydrocarbons in the Craton area. The destruction caused a loss of the reserve resources of the Palaeozoic amounting to nearly 13.3 billion tons. Asphaltic sandstones formed after the destruction of oil and gas may serve as an effective caprock which is beneficial to accumulation of hydrocarbons and formation of the pool sealed by asphaltic sandstones in the later stage. The destruction of the early Silurian hydrocarbons depends on the stratigraphic burial depth. The deep part under the northern slope of Tazhong is an area favorable to search of undestroyed Silurian oil reservoirs.  相似文献   
58.
塔里木河南岸地下水资源,卡要为受塔里水河控制的具有高矿化背景的地下水,在塔里木河洪水的淡化影响下,形成了一定范围的地下水淡化带.这种淡化水对油田供水具有战略意义,在一定程度上制约着油田建设的发展.通过对塔埋木河南岸地下淡水资源的分布特征与成因分析.为塔河南岸地下淡水资源的合理开发与利用指明了方向.  相似文献   
59.
陕北砂黄土区公路地质灾害及防治对策   总被引:8,自引:0,他引:8  
中国西北黄土的颗粒组成具有明显的地带性分布规律,自NW向SE可依次划分为砂黄土带、典型黄土带和粘黄土带。黄土高原北部地质灾害综合调查表明,砂黄土区公路地质灾害的主要类型包括黄土边坡滑塌灾害、路堤裂陷灾害、路桥变形和冲蚀灾害等。根据试验测试分析结果,公路地质灾害的形成主要受黄土本身的物质组成、结构及力学性质控制,人类工程活动的盲目性是诱发地质灾害的重要因素。文章在砂黄土公路地质灾害特征分析的基础上,提出加强边坡防护和冲蚀灾害防治是公路地质灾害防治的两个基本途径,并给出了针对性的防治对策。这不仅对该地区的公路建设具有重要的指导作用,而且对其它生命线工程如铁路、输油气管道、渠道等也具有重要的借鉴意义。  相似文献   
60.
1IntroductionHighway, as a kind of man-made structure, will become a part of the geographical environment and be impacted by all sorts of natural factors after it is finished. On the other hand, highway also brings some changes to the geographical environment. A highway often passes through different natural regions, so it must be adaptable to any geographical environments. On the basis of deep understanding of the geographical environment, service life and normal level of the highway can be e…  相似文献   
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