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531.
地质储存是减少CO2等温室气体向大气中人为排放的有效措施,深部咸水层是优先考虑的地下储存空间之一,准确评价CO2在深部成水层中的储存潜力是进行CO2地质储存研究的重要基础.本次研究以松辽盆地中央坳陷区深部咸水层为例,评价其储存CO2的潜力,并考虑储层物性参数的随机性,进行储存潜力的不确定分析.研究结果表明,中央坳陷区深部咸水层CO2地质储存理论潜力为5.34×10<'11>t,若考虑孔隙度不确定性,则储存潜力的随机分布区间为4.14×10<'11>-5.72×10<'11>t,且大于理论储存潜力值的概率约为58.3%,说明孔隙度的不确定性对储存潜力评价结果影响较大,在实际工程中应重点考虑这一问题. 相似文献
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"真烧假脱断"事故在煤田地质钻探施工中比较常见,容易误判为钻具脱扣或折断的烧钻事故。该事故多发生在夜班,以零时至凌晨5时为事故的多发时段;事故产生的主要原因是钻具接箍密封不严,水龙头堵塞,泥浆泵故障和其它因素引起的泥浆不能正常输送到孔底而产生。针对事故的特点,在实践中总结出"存疑求原、解释合理、逐一破劲、砸反结合"的处理原则和"稳、准、静、决"的处理步骤。郏县王集勘探区某孔和登封某勘探区某孔的处理结果表明,该处理原则和步骤切实可行,对指导同类事故的处理有一定的借鉴意义。 相似文献
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Dušan Polomčić Bojan Hajdin Zoran Stevanović Dragoljub Bajić Katarina Hajdin 《Hydrogeology Journal》2013,21(7):1519-1530
The Vi? Bare groundwater source is used to supply water to the population and industry of Obrenovac, one of the municipalities of Belgrade (the capital of Serbia). It is a typical riverbank filtration site; exploitation is performed through 30 drilled wells and two radial wells located in the meander of the Sava River. The established hydraulic connection between the river and tapped aquifer is so great that the river regime has a dominant influence on the aquifer. As a consequence of this, water-delivery reduction occurs in the dry months (summer–autumn), when the population needs water the most. Based on the data associated with the river’s gauges, precipitation, quantity of pumped water and groundwater-level fluctuation, a simulation of the groundwater regime for non-steady-state flow conditions has been undertaken through a numerical model. To overcome problems of water shortage during the dry season, the possibility of artificial recharge using an infiltration channel, made up of two connected parts, was analyzed. During the dry months, 80 % of the wells receive water partly from the infiltration channel. In this way, possibilities for extracting additional water are created. The application of this concept is discussed. 相似文献
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Xiaodong Wu Lin Zhao Tonghua Wu Ji Chen Qiangqiang Pang Erji Du Hongbing Fang Zhiwei Wang Yonghua Zhao Yongjian Ding 《Environmental Earth Sciences》2013,68(3):865-870
A large volume of underground gas in the permafrost region of the Qinghai-Tibetan Plateau has been identified. Although many studies were performed to investigate the soil organic carbon dynamics and Earth degassing in volcanic areas, this is the first report of a large amount of non-volcanic CO2 contained in permafrost. The gas was mostly CO2 (81.76 vol. %) and nitrogen (14.59 vol. %). The gas composition and the evidence from carbon stable isotope values (?23.9 ‰, PDB) suggested that the gases possibly had a deep origin. The gas emissions may be triggered by permafrost degradation, which means mitigation of the barrier effect of permafrost for the gas. In addition, plate tectonic processes may also lead to gas emissions, as the tectonic activity is strong in the area. Therefore, particular attention should be paid to the underground gases in the study of global change and permafrost degradation. 相似文献
538.
Correlation between incompetent beds and slope deformation at Badong town in the Three Gorges reservoir, China 总被引:2,自引:0,他引:2
Badong town is a new immigration area in the Three Gorges reservoir, China, which is built on many giant deep-seated landslides. In this region, the slope deformation is very severe and it is strongly correlated with the incompetent beds, which are distributed widely in the rock mass. In this paper, two giant deep-seated translational rock landslides used as study cases are Huangtupo landslide and Zhaoshuling landslide. Firstly, the composition materials, structures and deformation characteristics of the two landslides are analyzed. Then, the position, structure, mineral composition and the formation mechanism of the incompetent beds are studied in detail. Finally, based on the comparison of the position, mineral and structure between incompetent beds and sliding zones of the landslides, the correlations between incompetent beds and giant landslide are discussed. The results indicate that 13 large incompetent beds exist in the middle Triassic Badong Formation strata, which can be divided into three types as weak interlayers, crushed beds and groundwater corrosion zones. The dominant minerals in the incompetent beds are illite, chlorite, quartz and calcite. The contents of the clay minerals in different positions are quite distinct, and the maximum difference of clay content exceeds 70 %. In addition, it is found that the contents of minerals in incompetent beds are similar to the slide zones of the landslides. The initial deformation of slopes normally developed along the incompetent beds, which induced subsequent shear displacement easily. Under the effect of gravity, the deep slip zones were generated mainly along the incompetent beds and the failure mode evolved from creep to integral slide gradually. The results can provide an important reference for the mechanism analysis and prevention of landslides in Badong town. 相似文献
539.
Spatial distribution of surface soil water content under different vegetation types in northwest Guangxi, China 总被引:3,自引:1,他引:2
Wanxia Peng Tongqing Song Fuping Zeng Kelin Wang Hu Du Shiyang Lu 《Environmental Earth Sciences》2013,69(8):2699-2708
Geostatistical and statistical analyses were combined to examine the spatial distribution of soil water content under four vegetation types during the dry season, in the peak-cluster depression in the karst region in northwest Guangxi, southwest China. The soil water content significantly increased from farmland to plantation, secondary forest, and primary forest; whereas the variation coefficients, the sill (C 0+C), and total spatial variance increased, although the range decreased. The spatial distribution of soil water content in the different vegetation types had a high spatial autocorrelation. Different models produced a best fit for the semivariograms of the four vegetation types. Elevation and slope position were the primary factors influencing the spatial distribution of soil water content, with other key factors differing between the four vegetation types. Moreover, even though different specific factors influenced soil water content in the four vegetation types, the correlations and degrees of associations between the soil water content and these various factors differed. Therefore, the corresponding strategies for rational usage and management of water resources should be different for the four vegetation types in this region. 相似文献
540.