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1.
宁波软土盾构隧道施工地表沉降分析   总被引:4,自引:2,他引:2       下载免费PDF全文
通过对轨道交通1号线望春桥站—泽民站区间盾构施工地表沉降测试,分析了宁波软土盾构隧道施工引起的地表沉降规律,进而采用Peck公式、Celestino法、Vorster法、Sagaseta法、LoganathanPoulos法、Chi法、Park法、Yoshikoshi法、VerruijtBooker法、Loganathan法对横向地表沉降,采用Sagaseta法、修正Sagaseta法、Yoshikoshi法、修正Yoshikoshi法对纵向地表沉降分别进行拟合分析,结果表明:在宁波软土地层条件下,监测断面4D范围内的地表沉降发展较快,沉降变化速率较大;Peck公式、Celestino法、Vorster法、Chi法、Yoshikoshi法及Loganathan法对横向地表沉降拟合效果较好,纵向地表沉降宜采用修正Yoshikoshi法和修正Sagaseta法,为宁波以轨道交通盾构隧道施工地表沉降控制提供依据。  相似文献   

2.
董湘龙  丁卫撑  张文 《地质论评》2019,65(Z1):303-304
正土壤氡及其子体测量可用于寻找铀矿,寻找与放射性元素或断裂构造有内在联系的金属和非金属矿床,寻找地下水和地热资源,以及地震预报、断层确认、滑坡探测、民用建筑工程氡浓度调查等。当前测氡方法主要分为瞬时法和累积法,瞬时法包括Ra A卡法、α能谱法、闪烁瓶法等,累积法包括钋-210法、活性炭法、径迹法、热释光法、α杯法等。瞬时法成本低、操作简单、高效  相似文献   

3.
本文根据地热物探科研室近年来地热物探工作经验,提出一个简便、有效的城区地热物化探工作方法系列,即1米测温法、汞法、钋法加电法的方法系列。其中,以前三种方法组成一体为主,电法为辅,视条件允许配合。电法又包括了双极—双偶极法、电测深法、电剖面法和自然电场法,以双极—双偶极法为佳。文中简介了该方法系列的实质、特点和实验研究的效果与成果。  相似文献   

4.
一、前言水、空气、土壤中氡的测定方法有电离室法、活性炭吸附法,闪烁室法,双滤膜法、气球法及活性炭滤纸法等。目前在国内铀矿普查和勘探过程中,广泛采用的是电离室法,活性炭吸附法和闪烁室法。其仪器多数采用CГ-11,FD-118及FD-3002等测氡仪。这些方法的灵敏度和准确度仍然不能说是很高的。  相似文献   

5.
较系统评述了现有的各种命名与判定宝石颜色的方法,如命名法中的二名法、类似法、色度法和三要素法;判定法中的目测法、仪器测量法和对比法。指出它们均存在有不同程度的缺点,但相对比较起来,用色谱图系的对比法是目前较好的方法。  相似文献   

6.
张忠苗 《物探与化探》1990,14(2):101-107
近年随着在软土层上大量建设高层建筑,桩基础被广泛应用,而新的地基处理方法要求对每根桩的质量都须确保,由此一系列经济、快速、可靠的桩检方法应运而生。本文概要地阐述了桩的分类、作用、性能特征和十二种桩检方法,即理论公式法、静荷载法、静力经验公式法、动力公式法、锤击贯入法,机械阻抗法、应力波分析法、水电效应法、球击动测法、基频法、声波及其它测井法、波速动刚度法。指出多种方法综合检测的必要性。  相似文献   

7.
近年随着在软土层上大量建设高层建筑,桩基础被广泛应用,而新的地基处理方法要求对每根桩的质量都须确保,由此一系列经济、快速、可靠的桩检方法应运而生。本文概要地阐述了桩的分类、作用、性能特征和十二种桩检方法,即理论公式法、静荷载法、静力经验公式法、动力公式法、锤击贯入法,机械阻抗法、应力波分析法、水电效应法、球击动测法、基频法、声波及其它测井法、波速动刚度法。指出多种方法综合检测的必要性。  相似文献   

8.
测定非饱和土土-水特征曲线的溢出水校正称量法   总被引:1,自引:0,他引:1  
陈辉  韦昌富  李幻  曹华峰  吴二林 《岩土力学》2010,31(7):2141-2145
在利用压力板仪测定非饱和土的土-水特征曲线时,常用的取样称量法、溢出水称量法分别存在实测试样质量与实际试样质量不相等、实测排水量与实际排水量不相等等问题,从而造成试验结果失真。为此,溢出水校正称量法被引入用来消除取样称量法及溢出水称量法中存在的问题。通过取样称量法、溢出水称量法、溢出水校正称量法的对比研究发现,在同一基质吸力作用下,由取样称量法、溢出水称量法确定的试样饱和度均小于由溢出水校正称量法确定的试样饱和度,并对该现象进行了解释。随后,对取样称量法、溢出水称量法、溢出水校正称量法的适用范围进行了探讨。  相似文献   

9.
钻孔下套管方法综述   总被引:1,自引:0,他引:1  
本文介绍国外各种先进的下套管方法,包括ODEX法、SIM-CAS法、双回转器下套管法、CHRISTENSEN法、CABLE-O-CASING法以及套管冲击器下套管法.阐述了各种下套管法的工作原理、钻具结构及其优缺点.  相似文献   

10.
地下水污染调查中的地球物理方法   总被引:2,自引:0,他引:2  
钟秋 《地下水》2014,(2):57-58
地下水污染调查是国内外环境保护工作的重要研究课题。通过查阅前人的研究成果。总结了地下水污染调查的地球物理应用基础,主要的地球物理方法及其应用。主要的地球物理方法主要有电阻率法、大地电磁法、地质雷达法、放射性法、核磁共振法、地震勘探法等,这些方法对于不同的污染物有不同的特点,如电阻率法、大地电磁法多用于垃圾填埋场的污染,地质雷达法、核磁共振法和地震勘探法多用于有机污染。充分研究和合理选择这些方法,将使地球物理方法在地下水污染调查中发挥更重要的作用。  相似文献   

11.
太平洋北部铁锰结核富集区沉积物的元素地球化学特征   总被引:2,自引:1,他引:2  
鲍根德 《沉积学报》1990,8(1):44-56
本文对太平洋北部铁锰结核富集区沉积物的元素地球化学作了较为详细的研究。因子分析提供的信息表明,元素的分布主要受三个因子控制:(1)粘土及Fe、Mn氧化物水化物胶体的吸附作用;(2)生物化学作用过程有关的自生沉积作用;(3)海底页岩风化及附近海区的火山喷发作用。元素的来源:(1)Fe、Mn、Cu、Co、Ni、Zn、Cr、Cr、Mg、Al、Ti、K共生,主要来自粘土吸附;(2)C有机、N、Sr、Na及Si、Ca、Sr主要来自生物化学过程沉积;(3)Pb主要来源于岩石碎屑(火山喷发碎屑)。  相似文献   

12.
Prediction and search for gold deposits in the east of the Siberian Platform are problematic because the study area is overlain by a thick cover of MZ-KZ deposits. Search for gold deposits by the largest geological institutions using conventional methods have not yielded positive results, because the main attention was focused on the discovery of ancient gold-bearing conglomerates of the Witwatersrand type and on the evaluation of the gold ore potential of basic magmatism. Typomorphism of placer gold bears huge information about the genesis of native gold, both its primary endogenous origin and its exogenous transformation, which makes it possible to identify the formation type of mineralization, increases the reliability of the prediction of gold deposits, and ensures their purposeful search in the platform areas. The revealed indicative features of placer gold made it possible to substantiate the formation of the gold ore sources of Precambrian low-sulfide gold-quartz, gold-iron-quartzite, porphyry gold-copper, and gold-PGE mineralization and Mesozoic gold-silver, gold-rare-metal, and gold-sulfide-quartz mineralization in the east of the Siberian Platform. We have established that high-fineness placer gold with microinclusions of pyrite, arsenopyrite, quartz, and carbonates with recrystallized structures and lines of plastic deformation is specific to the ore sources of low-sulfide gold-quartz mineralization. A high content of Cu (up to 4%) in flaky high-fineness gold is one of indicators of porphyry gold-copper mineralization. The angular shape of gold grains, the fine fraction and high fineness of gold, its completely recrystallized and regrown internal structure, and the permanent presence of Fe, Bi, and Cu microimpurities and hematite, ilmenite, and corundum microinclusions are typical of gold-iron-quartzite mineralization. Flaky and laminated high-fineness gold particles with steady Pt, Pd, and Ni impurities and Pt-mineral phases and Au-Pt intergrowths in them testify to the ore sources of gold-PGE mineralization. Laminated and cloddy gold fractions of > 0.25-2.0 mm, the medium and low fineness of gold, its single-crystal or, sometimes, porous internal structure, the wide range of microimpurities (Pb, Zn, As, Sb, Cu, Te, etc.), and microinclusions of native Ag, adularia, Sr-barite, and calcite are indicators of gold-silver mineralization. Laminated, dendritic, and cloddy-angular gold grains, wide variation in gold fineness (307-950‰), and the presence of microinclusions of native bismuth, maldonite, arsenopyrite, and silver tellurides are indicative of gold-rare-metal mineralization. Laminated and cloddy gold grains, their size varying from dust to > 0.25 mm, their mono- and coarse-grained internal structure, wide variation in gold fineness (600-900‰), and the presence of Hg microimpurities (up to 6% and more) and microinclusions of quartz, calcite, pyrite, arsenopyrite, tellurides, selenides, and REE phosphates point to gold-sulfide-quartz mineralization. The established placer gold indicators of the particular formation types of ore sources in the east of the Siberian Platform made it possible to predict Precambrian gold deposits with low-sulfide-gold-quartz mineralization similar to the Kirkland Lake and Porcupine mines and gold deposits with Mesozoic gold-silver mineralization similar to the Cripple Creek mine. The developed criteria for determining the types of mineralization by indicative features of placer gold give an insight into the ore genesis and can be successfully applied to prediction and search for gold deposits and to evaluation of their gold resources.  相似文献   

13.
2004年新疆地质矿产勘查进展及2005年工作思路   总被引:3,自引:2,他引:3  
2004年新疆地质勘查工作在铜镍、金、铅锌、锑、钨、铁、煤和非金属等矿产勘查方面取得了重要进展,发现了一批矿产地,扩大了矿床远景,增加了资源储量,确定了一批有找矿前景的重要成矿区带、基础地质研究工作也有新发现和新认识,2005年地质勘查工作将继续坚持“主攻天山,深化阿尔泰山,开拓昆仑、阿尔金山”的总体布局和“区划、区调、物化探、勘查、科研五统一”的工作原则,主攻煤、富铁、铜镍、富铅锌、金、铀等国家和自治区急需的矿产及具有大型.超大型找矿前景和显开发效益的矿床.围绕找矿部署,开展基础性地质矿产调查工作和矿产资源评价工作;服务矿山开发,开展商业性矿产勘查工作;采取突出重点、加大投入、强化综合找矿、加强生产科研联合攻关等措施,努力实现地质找矿新突破。  相似文献   

14.
The primary halos of porphyry copper deposits are characterized by compositional zoning in three dimensions. Two ideal zoning patterns can be divided in accordance with the shape of primary halos in space: bell-shaped and anticline-shaped. In the process of alteration-mineralization, K, Si, (OH), Fe, Cu, Mo, Ag, S, Ba, Rb, Pb, Zn, As, etc. were imported, while Na, Ca, Mg, Fe, Al, Ti, Mn, V, Co, Sr, Pb, Zn, etc. were exported or became activated, and then transported and reprecipitated. Both import and export of Fe, Pb and Zn may have taken place. The fundamental factors controlling the zoning of primary halos are: the stability of complexes and the activity of elements; pH, Eh, the behaviour of sulfur and the sulphophile character of elements; the concentration of components and the regularities of isomorphism; temperature and pressure; and tectonic setting and lithological characters of wallrocks. The authors consider that the zoning patterns of primary halos in porphyry copper deposits are the outcome of integrated effects of various factors.  相似文献   

15.
流体构造动力学及其研究现状与进展   总被引:14,自引:1,他引:14  
流体构造动力学是介于流体地质学和构造地质学之间的一个重要前沿领域 ,主要研究由流体的温度和压力等物理状态及其变化、流体的迁移与运动和流体与岩石矿物发生化学反应等物理与化学过程所引起的构造作用和动力学机制 ,研究内容涉及流体与构造的关系、流体的构造作用方式、流体构造类型与动力学成因机制。对流体构造动力学主要研究方向的研究成果进行了总结和回顾 ,介绍了流体构造动力学的一些研究进展 ,并指出流体是地壳运动、造山作用及岩石的褶皱和断裂等构造过程的重要参与者和组织者。  相似文献   

16.
Variations in the composition and mineral assemblages of boronaluminosilciates (serendibite, grandidierite, kornerupine, and tourmaline) were studied in the abyssal and hypabyssal skarns of New York and California, United States, the Taezhnyi deposit of southern Yakutia, and deposits of the Pamirs, and compared to their occurrences around the world. The genesis of the boronaluminosilicates depends on the facies of the replaced skarns and the calcareous-skarn alteration of the primary composition of the host rocks. The substitution between Mg and Fe, as well as between Al, Si, and B, was studied in complex boronaluminosilciates and associated minerals. It was shown that f of serendibite is determined by that in the replaced skarn minerals (pyroxenes, spinel, sapphirine, and grandidierite) and is inherited in the replacing tourmaline and late silicates. Unlike serendibite, kornerupine is a typomorphic mineral of only bimetasomatic skarns of the abyssal facies. Serendibite, grandidierite, kornerupine, and tourmaline crystallized during the postmagmatic stage of the evolution of boron mineralization at skarn deposits of both the abyssal and the hypabyssal facies, at contact with magnesian carbonate sequences and desilicified aluminosilicate rocks.  相似文献   

17.
堵海燕  申维 《江苏地质》2015,39(4):609-616
从下列研究方向探讨了数学地球科学的新进展,即数据分析与数据挖掘(多点地质统计学,数据同化方法,数据挖掘和展示,时间序列分析,基于不规则数据集方法,数值分析方法与新算法)、非线性科学(多重分形模型,自组织临界理论,混沌理论,系统固有的复杂性,非线性随机过程的动态建模)、遥感(差分干涉合成孔径雷达,最先进雷达遥感,新的星载和地基微波技术,与遥感相结合的地理信息系统环境建模)、建模(新的数学变形模型与方法,地下蓄水层的流动与运送的预测模型,新油气发现模型,石油采收数学模型,空间与时间建模)、资源环境定量评价(复杂储存环境的地震特性综合反演,油井与储藏动态数据的实时同化处理,不确定性评估储藏动态新方法,资源评价和风险分析的新模式,环境地球化学,定量环境地质学)等  相似文献   

18.
白中科 《地学前缘》2021,28(4):1-13
国土空间生态保护与修复是实现美丽中国、关系中华民族永续发展的根本大计。本文采用文献资料综合分析法、系统回顾法、实证分析法、类比分析法、趋势外推法、政策环评等相结合的方法开展了一系列工作:从国家方略、顶层设计两个方面,梳理了国土空间生态保护与修复的脉络;从国土空间生态修复规划、技术路经与方法、野外台站和科研样地等角度,阐明了国土空间生态保护与修复研究的方法论;举例辨析了国土空间生态保护与修复的若干“伪生态”和“假技术问题”;指出了国土空间生态保护与修复发展的战略方针、战略目标、战略方向、战略原则、战略重点、战略对策;从生态保护与修复的重大科学问题和热点、语境分析、分区分类、差异化、生态补偿机制等5个方面,提出了助推中国国土空间生态保护与修复需要的科技支撑;讨论了“两屏三带”、科学推进生态修复,以及管理逻辑与技术逻辑融合问题。研究结果为破解国土空间“整体保护、系统修复与综合治理”过程中生态要素的综合性与管理事权的部门化、生态空间的连续性与区域的政区化、生态工程的长期性与行政管理的届次化三大矛盾,提供了科学依据。  相似文献   

19.
天山志留纪生物地理特征及分区   总被引:1,自引:0,他引:1  
天山志留纪生物丰富,包括笔石、珊瑚、腕足类、层孔虫等10多个门类,由于伊塞克—伊犁板块的阻隔和尼古拉耶夫—图拉苏断裂带的影响,天山南北具有两种不同的古地理环境。根据生物组合和沉积相特征,将天山归入古亚洲域,并细分为2个省,3个亚省:I_1准噶尔—哈萨克斯坦省,包括博罗科努山、那拉提山、北山、西准噶尔和哈萨克斯坦;I_1~1西准噶尔—北天山亚省,包括早志留世笔石相碎屑岩,中志留世珊瑚、腕足相碳酸盐岩和晚志留世杂色碎屑岩夹碳酸盐岩,局部含少量珊瑚腕足类;I_2南天山省,包括新疆南天山和原苏联南天山和中亚;I_2~1土尔克斯坦—哈尔克山亚省,包含早志留世碎屑岩和碳酸盐岩,局部含笔石,中晚志留世碳酸盐岩和碎屑岩,含丰富的珊瑚、腕足类、层孔虫,常形成珊瑚-层孔虫礁,火山岩不发育。I_2~2努腊套—费尔干纳亚省。整个志留纪为笔石相砂页岩沉积,火山活动微弱。  相似文献   

20.
Although the Chinese people have, through continuous efforts, built the constantly improving Yellow River flood control system, and created a miracle which has been tranquil for over 50 years, the tendency for the downstream watercourse of the Yellow River to uplift every year has not been fundamentally curbed, and the aboveground river is still the “scourge” of the sons and daughters of the Yellow River. By the use of a variety of modern investigation and survey methods, the geological environment characteristics of the downstream of the Yellow River have been identified basically, including the environmental and geological factors affecting the stability of aboveground rivercourse of the lower Yellow River such as the active fracture of the lower Yellow River, crustal uplift, land subsidence, seismic activity, geological conditions of dike foundation engineering, hydrodynamic conditions of rivers, and geomorphology of watercourses. After a comprehensive analysis of the inability mode of aboveground river on the downstream of the Yellow River and its corresponding impact factors, by using the fuzzy comprehensive evaluation method, we have evaluated the crustal stability of the aboveground river, dike foundation stability, watercourse landform stability and overall stability. The results of comprehensive results show that the stability of downstream aboveground rivercourse of the Yellow River can be divided into four grades and 11 sections, i e. “basically stable, unstable, very unstable and extremely unstable”. On the basis of the stability segmentation, we consider the influence of integrally the future structural faults, earthquakes, the difference of watercourse between forward and backward heights of dikes, river regime and river type, historical crevasses, foundation soil liquefaction and seepage deformation, and find out 17 most unstable danger points. Finally, from 17 danger points, we select 7 danger points which are most prone to instability including Wuzhi, Zhongmou, Kaifeng, Fengqiu, Dongming, Changyuan and Dong’e. The calculation and analysis of the range and area inundated by 7 danger points, area, and number of people threatened, possible economic loss, and environmental damage, the inability caused by any one of 7 points could bring disastrous consequences to the downstream.  相似文献   

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