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971.
972.
Fault-Growth Pattern of the South Margin Normal Fault of the Yuguang Basin in Northwest Beijing and its Influencing Factors 总被引:4,自引:0,他引:4
Based on high-resolution remote sensing image interpretation, digital elevation model 3-D analysis, field geologic field investigation, trenching engineering, and ground-penetrating radar, synthetic research on the evolution of the Yuguang Basin South Margin Fault (YBSMF) in northwest Beijing was carried out. We found that the propagation and growth of faults most often occurred often at two locations: the fault overlapping zone and the uneven or rough fault segment. Through detailed observation and analysis of all cropouts of faults along the YBSMF from zone a to zone i, we identified three major factors that dominate or affect fault propagation and growth. First, the irregularity of fault geometry determine the propagation and growth of the fault, and therefore, the faults always propagate and grow at such irregular fault segments. The fault finally cuts off and eliminates its irregularity, making the fault geometry and fault plane smoother than before, which contributes to the slipping movement of the half-graben block in the basin. Second, the scale of the irregularity of the fault geometry affects the result of fault propagation and growth, that is, the degree of the cutting off of fault irregularity. The degree of cutting off decreases as irregularity scale increases. Third, the maximum possible slip displacement of the fault segment influences the duration of fault propagation and growth. The duration at the central segments with a large slip displacement is longer than that at the end segments with a smaller slippage value. 相似文献
973.
974.
Remote computation as well as remote design is a hot topic nowadays and becoming popular and also more diversified in use in the recent years. This study applies the retaining wall design as an example to construct a mechanism for complicated computation in civil engineering directly in a network server for risk assessment, so that a user can easily carry out the computation analysis with any available device via internet by using a personal computer or mobile device. To develop a convenient as well as time-saving operating environment for the remote analysis, an effective interactive interface is also developed. In the retaining wall design, this study provides users with the Rankine method, Coulomb method, and theory of plasticity to perform the objective analysis. The automatic checking system of the program will validate the computation results, under this circumstance, users need not worry about whether their input data and calculated results are consistent with practical standards and regulations or not. Various factors of safety, for risk assessment, resulting from the three kinds of computational methods are compared to verify whether there is any significant difference among them while designing a safe retaining wall overall. 相似文献
975.
Nano-hematites, i.e., hematites with nanoparticle-, nanorod-, and nanotube-like morphologies, were synthesized via the hydrothermal method by controlling the reaction time, temperature, and reactant concentration. The nano-hematites of different crystal shapes all exhibited band gaps within the visible-light region (1.56–2.1 eV). Further, they showed weak ferromagnetic behavior, and their coercive magnetic field was larger than that of the bulk hematite. Moreover, all the nano-hematites also exhibited high photocatalytic activities during the degradation of methylene blue under visible-light irradiation. The experimental data fitted the Langmuir–Hinshelwood kinetics model very well. The nanorods had the highest photocatalytic rate constant per unit surface area, possibly owing to a higher aspect ratios; this lowers the electron–hole recombination rate. These results suggest that the crystal morphology of hematites has a significant effect on their physical and photocatalytic properties. Therefore, controlling the morphology of the materials is essential for obtaining well-tailored photocatalysts. 相似文献
976.
随着全站仪在测量工作中的广泛使用,以坐标为观测值的数据处理成为内业工作的主要内容。根据最小二乘滤波原理,将工程岩土体变形监测中所获得的坐标观测值及其他常规观测值进行联合平差。结果表明,滤波后变形点的点位精度最大可提高1.35 mm,最弱点亦提高0.94 mm,均明显高于直接观测结果,而且各类观测值之间所形成的约束条件进一步增强了平差结果的可靠性。 相似文献
977.
青藏高原岩石圈演化的记录:藏北超钾质及钠质火山岩的岩石学与地球化学特征 总被引:44,自引:12,他引:44
藏北鱼鳞山超钾质火山岩为一中等规模的熔岩被, 可分为三期。前两期主要为霞石黝方白榴石响岩、霞石白榴斑岩等, 后期主要为方钠石霓石粗面岩、霓霞粗面岩等。时代为18~30 Ma。本区超钾质岩浆 Si O2 强烈不饱和、强碱性、高度富集 L R E E及 L I L E、放射成因 Sr、 Pb 及非放射成因 Nd 同位素 (86 Sr/87 Sr= 0708766~0709162, 206 Pb/204 Pb= 18882888~ 19104751, 207 Pb/204 Pb= 15642037 ~ 15828458, 208 Pb/204 Pb= 39138921 ~ 39686835 及143 Nd/144 Nd= 0512116 ~0512342),其上述特征指示岩浆源区为受到地壳物质强烈交代的富集 E M I I型地幔。藏北拉嘎拉钠质碱性橄榄玄武岩为高原面上的剥蚀残丘, 时代为60 Ma。其岩石学、 R E E、微量元素及 Sr Nd Pb 同位素指示了岩浆源区为受到洋壳俯冲物质交代的轻度富集地幔。本研究结果指示, 羌塘高原南部富集地幔的形成可能是受到印度板块俯冲的影响。 相似文献
978.
Yuyu Wan Shanghai Du Guangyu Lin Fengjun Zhang Tianfu Xu 《Arabian Journal of Geosciences》2017,10(3):71
This study focused on the target injection layers of deep saline aquifers in the Shiqianfeng Fm. in the Carbon Capture and Sequestration (CCS) Demonstration Projects in the Ordos Basin, northwestern China. The study employed a combination method of experiments and numerical simulation to investigate the dissolution mechanism and impact factors of CO2 in these saline aquifers. The results showed (1) CO2 solubility in different types of water chemistry were shown in ascending order: MgCl2-type water < CaCl2-type water < Na2SO4-type water < NaCl-type water < Na2CO3-type water < distilled water. These results were consistent with the calculated results undertaken by TOUGHREACT with about 5% margin of error. CO2 solubility of Shiqianfeng Fm. saline was 1.05 mol/L; (2) compared with distilled water, the more complex the water’s chemical composition, the greater the increase in HCO3 ?concentration. While the water’s composition was relatively simple, the tested water’s HCO3 ?concentrations were in close accord with the calculated value undertaken by the TOUGHREACT code, and the more complex the water’s composition, the poorer the agreement was, probably due to the complex and unstable HCO3 ? complicating matters when in an aqueous solution system including both tested HCO3 ?concentration and calculated HCO3 ?concentration; (3) the CO2 solubility in the saline at the temperature conditions of 55 °C and 70 °C were 1.17 and 1.02 mol/L. When compared with the calculated value of 1.20 and 1.05 mol/L, they were almost the same with only 1 and 3% margin of error; concentrations of HCO3 ? were 402.73 mg/L (0.007 mol/L) and 385.65 mg/L (0.006 mol/L), while the simulation results were 132.16 mg/L (0.002 mol/L) and 128.52 mg/L (0.002 mol/L). From the contrast between the tested data and the calculated data undertaken by the TOUGHREACT code, it was shown that TOUGHRACT code could better simulate the interaction between saline and CO2 in the dissolution sequestration capacity. Therefore, TOUGHREACT code could be used for the inter-process prediction of CO2 long-term geological storage of CO2; (4) The Ca2+ concentration and SO4 2?concentration in saline water had less effect on the solubility of CO2 and HCO3 ?concentration. In addition, TDS and pH values of saline affected not only the solubility of CO2, but also the conversion of CO2 to HCO3 ? due to that they can affect the activity and acid-base balance. So in fact, we just need to consider that the TDS and pH values are main impact factors in the dissolution sequestration capacity of CO2 geological sequestration in deep saline aquifers. 相似文献
979.
造山带异源浆混花岗岩理论与方法研究 总被引:2,自引:0,他引:2
1:5万花岗岩填图方法在区调工作中推广以来,在造山带花岗岩调查实践中,由于造山作用及过程的复杂性,花岗岩浆的多源及多样性,使同源岩浆演化理论及方法遇到了难题。文章在新一轮1:25万造山带试点图幅,在对同源岩浆演化理论及方法的适用性进行探索的同时,提出了异源浆混理论指导造山带内部浆混花岗岩(H型花岗岩)的填图方法。并就异源浆混花岗岩鉴别标志等作了系统总结,提出了浆混组合、浆混单元、浆混体,填图的理论方法体系;给予了浆混花岗岩明确的定义。 相似文献
980.