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61.
近年来,随着经济的飞速发展,人类的生产活动加剧了部分地质灾害的产生,尤其是矿产行业,如何对矿区的地表沉陷进行有效监测成为众多学者的研究方向之一.随着雷达卫星的陆续布置,差分雷达干涉测量方法(D-InSAR)的高精度、全天候、成本低的特点使得它成为矿区沉降监测的重要手段之一.通过利用D-InSAR技术对试验区域的雷达影像进行双规差分法处理得到沉降信息,比对实际的测量数据,证明了D-InSAR技术在地表形变上的实用性.  相似文献   
62.
捷联惯导系统(strapdown inertial navigation system,SINS)在进行导航解算前需要粗对准提供初始姿态角,载体受多种因素影响和制约,在微幅晃动或运动状态下,需要进行动基座粗对准.从惯性系对准原理出发,讨论了基于比力和速度矢量的两种动基座粗对准解算方案,分析了位置误差、速度误差、杆臂误差对动基座粗对准的影响.结果表明,惯性系对准方法能够满足SINS粗对准的要求,速度误差和杆臂误差是制约对准精度与速度的主要因素,机动性强的轨迹能够加快对准速度,基于速度矢量的解算方案能够有效减弱姿态角收敛过程中的抖动,以提高对准效率.  相似文献   
63.
The Anshan–Benxi iron producing area, which is located at the northeastern margin of the North China Craton, is the main distribution area of Archaean BIFs in China. In their eastern part, including the Gongchangling and Waitoushan deposits, BIFs mainly are hosted in the Archaean middle Anshan Group. Amphibolites are widely distributed in the iron‐bearing rock series, reflecting the tectonic setting of BIFs. Amphibolites not only have MORB‐like compositional characteristics, but also have island arc‐like ones, and they are consistent with back‐arc basin basalts (BABB). In the study area, the protolith of amphibolites belongs to Okinawa‐type BABB; it indicates that tectonic setting of BIFs is the intra‐continental back‐arc basin. In the study area, the formation of sedimentary basins for BIFs had been associated with oceanic plate subduction. Amphibolites from Gongchangling deposit are characterized by relative enrichments in LILE and LREE, and depletions in HFSE. This indicates that they had a relatively large influence of subduction in their formation. Amphibolites from Waitoushan deposit are characterized by relative enrichments in LILE without conspicuous depletions in HFSE, indicating relatively low subduction rates. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
64.
65.
泥石流流域岩性的坚固系数与暴发频率的关系   总被引:2,自引:0,他引:2  
鲁科  余斌  韩林  谢洪 《地球科学进展》2011,26(9):980-990
坚硬岩性地区的泥石流暴发频率较低在定性上基本可以概括岩性与泥石流暴发频率的关系,但目前还没有定量地描述岩性与泥石流暴发频率的关系。以四川省17个泥石流流域作为研究对象,通过现场调查研究泥石流形成区和堆积区粗化层颗粒的岩性、硬度以及泥石流的暴发频率,得出:①泥石流堆积区岩性组成特征基本可以代表形成区的岩性组成特征;②用地...  相似文献   
66.
火是地球系统的重要组成部分,与气候、植被、生物地球化学循环和人类活动密切相关。火对全球气候和生态系统的影响已成为目前全球变化研究的一个热点。火灾发生后会在周围的环境中留下许多燃烧产物,如黑碳、木炭屑、多环芳烃、左旋葡萄糖等,它们广泛存在于海洋、湖泊、河流、土壤和陆地风成沉积物中;还会留下一些火灾痕迹,如树木火疤、土壤磁...  相似文献   
67.
王志章  韩海英 《地学前缘》2011,18(5):296-302
现代油藏描述提倡勘探开发一体化,真正实现测井与地震信息匹配,实现静态信息与动态信息结合,最终由定性走向定量。重点阐述了现代油藏描述中,通过集成高分辨率的岩石物理数据、中分辨率的测井数据及低分辨率的地震数据,采用储层自动划分对比及储层结构分析技术、沉积微相自动识别技术、波形差异分析法预测高产气区技术对不同勘探开发阶段、不...  相似文献   
68.
复合地基是通过褥垫层的调整作用,充分发挥桩间土的承载作用,使桩土共同承担荷载的地基。基于复合地基的实际工况,设计了一种单桩复合地基静载荷试验系统,既体现了褥垫层的调整作用,又可测得复合地基中桩体、桩问土、复合地基的荷载与其相应的沉降,同时可得出复合地基受力过程中桩土荷载分配过程与桩土应力比,提示了复合地基工作机理。通过工程实例测试,探讨了复合地基的工作机制,为复合地基的科研、设计与检测提供了依据。  相似文献   
69.
In an effort to evaluate the Cretaceous magnetostratigraphy for the Korean Peninsula and to establish the tectonic coherence of its various elements, we collected paleomagnetic data from 121 samples from 20 sites within the Chilgok Formation (108.3–109.9 Ma) in the Gyeongsang Basin. Together with previously published data, we evaluate the results from a total of 163 sites in the basin.We combine our age model with results from recent stratigraphic, paleomagnetic and radiometric geochemical studies. In this study, we found that two distinct declination shifts decrease with younging direction, indicating two clockwise rotational events of the Korean Peninsula with respect to the Eurasia continent. The earlier event took place during 130–100 Ma (Phase I, newly termed “Goguryeo Disturbance”) and a later one during 80–50 Ma (Phase III, belonging to “Bulguksa Orogeny”). The mean rotation rate in the interval from 115.2 to 103.8 Ma (Phase I) is about 0.74°/Ma, while the rate from 90.9 to 79.8 Ma (Phase II) is 0.19°/Ma. Based on paleolatitude change during Phase I, we infer that the Korean Peninsula (eastern part of the Sino-Korea Block) migrated southward about 300 km after the complete amalgamation of the Sino-Korea Block into the Eurasian continent resulting in N–S compression within the Korean peninsula and Manchuria. Large-scale strike-slip faults (e.g., Tan-Lu Fault, Okcheon Boundary Fault) were probably rejuvenated in the Sino-Korea Block during Phase I.  相似文献   
70.
The Hanjiang River, the largest tributaries of the Changjiang (Yangtze) River, is the water source area of the Middle Route of China’s South-to-North Water Transfer Project. The chemical and strontium isotopic compositions of the river waters are determined with the main purpose of understanding the contribution of chemical weathering processes and anthropogenic inputs on river solutes, as well as the associated CO2 consumption in the carbonate-dominated basin. The major ion compositions of the Hanjiang River waters are characterized by the dominance of Ca2+ and HCO3 , followed by Mg2+ and SO4 2−. The increase in TDS and major anions (Cl, NO3 , and SO4 2−) concentrations from upstream to downstream is ascribed to both extensive influences from agriculture and domestic activities over the Hanjiang basin. The chemical and Sr isotopic analyses indicate that three major weathering sources (dolomite, limestone, and silicates) contribute to the total dissolved loads. The contributions of the different end-members to the dissolved load are calculated with the mass balance approach. The calculated results show that the dissolved load is dominated by carbonates weathering, the contribution of which accounts for about 79.4% for the Hanjiang River. The silicate weathering and anthropogenic contributions are approximately 12.3 and 6.87%, respectively. The total TDS fluxes from chemical weathering calculated for the water source area (the upper Hanjiang basin) and the whole Hanjiang basin are approximately 3.8 × 106 and 6.1 × 106 ton/year, respectively. The total chemical weathering (carbonate and silicate) rate for the Hanjiang basin is approximately 38.5 ton/km2/year or 18.6 mm/k year, which is higher than global mean values. The fluxes of CO2 consumption by carbonate and silicate weathering are estimated to be 56.4 × 109 and 12.9 × 109 mol/year, respectively.  相似文献   
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