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71.
This work presents the stratigraphy and facies analysis of an interval of about 2500 m in the Langhian and Serravallian stratigraphic succession of the foredeep turbidites of the Marnoso‐arenacea Formation. A high‐resolution stratigraphic analysis was performed by measuring seven stratigraphic logs between the Sillaro and Marecchia lines (60 km apart) for a total thickness of about 6700 m. The data suggest that the stratigraphy and depositional setting of the studied interval was influenced by syndepositional structural deformations. The studied stratigraphic succession has been subdivided into five informal stratigraphic units on the basis of how structurally controlled topographic highs and depocentres, a consequence of thrust propagation, change over time. These physiographic changes of the foredeep basin have also been reconstructed through the progressive appearance and disappearance of thrust‐related mass‐transport complexes and of five bed types interpreted as being related to structurally controlled basin morphology. Apart from Bouma‐like Type‐4 beds, Type‐1 tripartite beds, characterized by an internal slurry unit, tend to increase especially in structurally controlled stratigraphic units where intrabasinal topographic highs and depocentres with slope changes favour both mud erosion and decelerations. Type‐2 beds, with an internal slump‐type chaotic unit, characterize the basal boundary of structurally controlled stratigraphic units and are interpreted as indicating tectonic uplift. Type‐3 beds are contained‐reflected beds that indicate different degrees of basin confinement, while Type‐5 are thin and fine‐grained beds deposited by dilute reflected turbulent flows able to rise up the topographic highs. The vertical and lateral distribution of these beds has been used to understand the synsedimentary structural control of the studied stratigraphic succession, represented in the Marnoso‐arenacea Formation by subtle topographic highs and depocentres created by thrust‐propagation folds and emplacements of large mass‐transport complexes. 相似文献
72.
作为极度缺水的鄂尔多斯盆地西南缘地区,针对白垩系含水地层采水的供水井很多,但供水井水质恶化和水量减小的现象较为普遍,其原因主要是井身结构严重不合理所致。通过对造成供水井质量恶化的原因分析,找出了止水方法的不合理性与泥岩缩径造成井身变形而致水量减小的问题实质,提出了科学合理的成井方案,从而有效地解决了供水井质量恶化问题,提高了供水井使用寿命。 相似文献
73.
简述了深孔岩心钻探破碎岩层护壁堵漏的重要性,注浆参数选择,水泥浆配比、速凝剂掺量的掌握,注浆施工中需把握的几个技术环节及注意事项,注浆施工经验总结及注浆效果评价等。 相似文献
74.
用钻井施工技术手段,对煤矿的瓦斯进行抽排放是降低煤矿安全风险的有效途径之一,也是对煤矿安全生产潜在风险的一种防范。通过钻井的方法,形成瓦斯抽排放井进行瓦斯的抽排放是一项既经济又快捷的有效方式,对煤矿的安全生产有着极为重要的意义。 相似文献
75.
在分析人工造浆阶段和风动造浆阶段原理及优缺点的基础上,开发研制出射流式水泥液制造器。通过对该设备主要构成部分结构的介绍,说明了其工作原理和使用方法。焦煤集团九里山矿14101工作面和古汉山矿11092(西)工作面的堵水实践证明,该设备的堵水率为100%,不仅可以提高注浆的速度及质量,降低劳动强度,改善注浆工地环境条件,而且具有价格便宜、设备安装简便、操作简单、容易维护,不受场地、注浆量大小、注浆点远近的限制等优点。 相似文献
76.
Can the diffuse double layer theory describe changes in hydraulic conductivity of compacted clays? 总被引:1,自引:0,他引:1
Robrecht M. Schmitz 《Geotechnical and Geological Engineering》2006,24(6):1835-1844
Observations related to modifications of the hydraulic conductivity of compacted soils as a consequence of intentional compositional
variation of the percolating fluid are often attributed vaguely to calculated changes in double layer thickness. The same
calculated decrease or increase in double layer thickness is interpreted differently, depending on which (unconsciously held)
boundary conditions authors take into account. The interpretations of different authors seem to be paradoxical only if the
boundary conditions have not been mentioned. On the basis of a literature survey and own previously published test results
the different boundary conditions have been grouped and divided into classes. With this division the interpretation of changes
in double layer thickness will lead to unique interpretations and predictions of changes in hydraulic conductivity. 相似文献
77.
在锚固工程成孔中,软土含砾地层成孔困难,钻进效率低,效率效益差,针对这种情况分析了地层特点和采用不同成孔方法施工存在的问题,找出了一种比较适应的钻进成孔方法,并通过生产实践证明效果较佳,为软土含砾地层倾斜孔成孔提供了一种新方法。 相似文献
78.
79.
The viscous behaviour of laterite slurries was characterized by measurements of shear stress at constant and changing shear rates. Steady state stresses were obtained after accounting for the settling solids: the values show that the fluids possess viscosities of order 100 mPa s and are moderately shear-thinning, for solid volume fractions from 0.06 to 0.18 and for shear rates between 10 and 1000 s−1. Transient stress measurements were made for steps down in shear rate and for ramps down and up in shear rate. It was found that the Bingham–Maxwell model provides good fits to the transient data, both at low concentrations, where yield behaviour is dominant, and at high concentrations, where elasticity is dominant. For volume fractions of 0.10 or greater, relaxation times were found from step tests to be of order 10 s, but relaxation times found from the ramp tests were generally several times higher. 相似文献
80.
报道了以NH4H2PO4为基体改进剂,采用悬浮体制样石墨炉原子吸收光谱法直接测定琥珀中微量铅的方法。试验了影响测定的主要因素。在优化实验条件下。方法的检出限为0.038μg/g,Pb的质量浓度为0~80μg/L时,工作曲线线性关系良好。对于ω(Pb)=5.71μg/g样品的测定,相对标准偏差(RSD,n=5)为6.83%。 相似文献