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481.
设计了一套静力触探模型箱试验装置,该装置可以在模型箱水平面内任意位置进行贯入试验,贯入速率在一定范围可控,贯入倾角可调节。将该装置用于TJ-1模拟月壤静力触探力学特性的研究,试验结果表明:地基表层模拟月壤发生刺入剪切破坏;贯入阻力随贯入深度的增加而增加;探杆周围同一深度处土体的水平土压力表现出轴对称特征,其值在探头靠近土压力盒过程中逐渐增大至最大值,后随探头远离土压力盒又逐渐减小至0,且不同深度土体水平土压力峰值随贯入深度增加而增大;贯入点正下方土体的垂直土压力随贯入深度的增加而增加,主要影响范围约为距探头200 mm处。基于以上试验研究,表明该模型箱的设计是合理的,且TJ-1模拟月壤力学特性的研究成果能够为将来涉及到TJ-1模拟月壤的航天试验提供必要的技术参考。 相似文献
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锌离子污染对膨润土一维压缩特性影响试验研究 总被引:3,自引:0,他引:3
为研究锌离子对膨润土重塑土压缩特性的影响,对人工制备的受不同浓度Zn2+污染的高含水率膨润土开展一维压缩、自由膨胀率、物理化学性质和扫描电镜试验。试验结果表明,在竖向压力低于某临界值(200 kPa)时,相同压力下随着Zn2+浓度增大,膨润土的孔隙比和压缩指数均降低,但当Zn2+浓度高于某临界值(0.02 mol/L)时,继续增加污染浓度膨润土的孔隙比基本保持不变,压缩指数略有降低。当竖向压力超过该临界值(200 kPa)后,膨润土的孔隙比基本不受孔隙液物理化学性质影响,仅由竖向压力决定。此外,随着孔隙液Zn2+浓度增大,膨润土的孔隙液pH值和土样比表面积减小,颗粒直径增大,膨润土中蜂窝状结构遭到破坏,黏土矿物片逐渐团聚成大直径颗粒,小孔隙消失,生成一些大的团粒间孔隙。 相似文献
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ABSTRACTThe South China Uranium Province (SCUP) contains the largest number of discovered uranium deposits in China. This province includes seven uranium mineralization belts, at Wuyishan, Taoshan–Zhuguang, Chenzhou–Qinzhou, Gan–Hang, Xixia–Luzong, Mufushan–Hengshan, and Xuefengshan–Jiuwandashan. The uranium deposits can be classified according to their ore-hosting rocks into four general types: granite-, volcanic-, black-shale-, and sandstone-related. These uranium deposits crop out at the peripheries of Cretaceous–Neogene (K–N) redbed basins or are connected to the basins by NE–SW- to NNE–SSW-trending regional faults. Most of the volcanic-related uranium deposits were formed during the mid-Cretaceous (118 to 88 Ma); granite-related deposits have a wider range of ages from 124 to 11 Ma; the black-shale-related deposits have ages of 120 to 7 Ma; sandstone-related deposits yield ages of 111 to 22.5 Ma. As such, these four types of uranium deposits in South China have similar ages, irrespective of location, and are similar in age to K–N redbed basins in this region. δDVSMOW(fluid) and δ18OVSMOW(fluid) values of the volcanic-related uranium deposits generally range from – 105.9‰ to – 38.0‰ and – 11.1‰ to +5.3‰, respectively. The black-shale-related uranium deposits yield δDVSMOW(fluid) and δ18OVSMOW(fluid) values of – 74.5‰ to – 33.0‰ and – 4.4‰ to 9.3‰, respectively. However, the granite-related uranium deposits have a much wider range of δDVSMOW(fluid) and δ18OVSMOW(fluid) values from – 104.4‰ to – 23.1‰ and – 9.4‰ to +7.3‰, respectively. H–O isotopic compositions of the SCUP ore-forming fluids are similar to those of basinal fluids, again demonstrating the link between the uranium deposits and the basins. The spatial–temporal relationships and fluid isotopic similarities between the K–N basins and uranium mineralization indicate that the uranium deposits of the SCUP are genetically related to the K–N redbed basins, and are unconformity-related uranium deposits. 相似文献
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以鄂尔多斯盆地环县—正宁地区三叠系延长组长9为研究对象,结合野外露头和岩心观察及测井资料分析,通过点、线、面研究步骤,精细刻画研究区延长组长91、长92沉积相特征及演化规律,为后期石油勘探开发做好指导工作.研究表明:环县—正宁地区的沉积相类型为辫状河三角洲相和湖相沉积;其中辫状河三角洲平原亚相在露头区最为典型,辫状河三... 相似文献
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针对鄂尔多斯盆地南部延长组长7段富有机质泥页岩岩石学特征及生烃潜力认识不清的问题,通过对研究区泥页岩的岩石学、矿物组成、有机地球化学、孔隙类型及沉积模式精细研究,结果表明:研究区主要存在3种不同类型的泥页岩,分别是泥质碎屑流成因的块状泥岩、浊流成因的正粒序泥岩及沉积于静水环境中的纹层状泥岩.块状泥岩和正粒序泥岩含有较多的陆源碎屑矿物,纹层状泥岩碳酸盐矿物含量高,同时含有较高的有机碳及可溶烃和热解烃,它们的干酪根类型以Ⅱ型为主,含有少量Ⅰ型.泥页岩储集空间主要为粒间孔、粒内孔及微裂缝,有机质孔少见,纹层状泥岩孔隙类型多样,储集空间大.泥质碎屑流形成的块状泥岩沉积在湖盆坡脚处,浊流成因的正粒序泥岩及纹层状泥岩广泛沉积于湖盆中心,且厚度大. 相似文献
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Bofeng Li Yunzhong Shen Xingfu Zhang Chuang Li 《International journal of geographical information science》2013,27(8):1572-1592
Affine transformation that allows the axis-specific rotations and scalars to capture the more transformation details has been extensively applied in a variety of geospatial fields. In tradition, the computation of affine parameters and the transformation of non-common points are individually implemented, in which the coordinate errors only of the target system are taken into account although the coordinates in both target and source systems are inevitably contaminated by random errors. In this article, we propose the seamless affine error-in-variables (EIV) transformation model that computes the affine parameters and transforms the non-common points simultaneously, importantly taking into account the errors of all coordinates in both datum systems. Since the errors in coefficient matrix are involved, the seamless affine EIV model is nonlinear. We then derive its least squares iterative solution based on the Euler–Lagrange minimization method. As a case study, we apply the proposed seamless affine EIV model to the map rectification. The transformation accuracy is improved by up to 40%, compared with the traditional affine method. Naturally, the presented seamless affine EIV model can be applied to any application where the transformation estimation of points fields in the different systems is involved, for instance, the geodetic datum transformation, the remote sensing image matching, and the LiDAR point registration. 相似文献