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重庆市南川铝土矿整装勘查项目是全国第一批整装勘查项目之一,ZK4321钻孔是该矿区目前已施工的最深钻孔。介绍了该钻孔钻探施工工艺,为以后在同类地层钻孔施工提供了经验。 相似文献
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贵州正安旦坪铝土矿大精查项目位于黔北典型岩溶区,为在钻探施工中有效避开岩溶,减少损失,提高勘查效率,达到铝土矿勘探定孔目的,在基本掌握研究区地质背景与地球物理特征的基础上开展物探瞬变电磁法测量。本文简单介绍了物探瞬变电磁法(TEM)的工作原理及探测方法,着重通过在已知钻遇溶洞钻孔ZK14604开展方法性试验,选取合适观测参数,再结合地质、钻探资料对物探断面及平面切图视电阻率异常特征进行综合研究定孔,根据已知到未知的原则,逐步对矿区其他拟布钻孔展开测量。据钻探成果资料显示,研究区已施工物探定孔均有效避开隐伏岩溶,物探成果得到了有效验证。表明利用瞬变电磁法在岩溶区铝土矿勘查定孔中能取得较好效果,可为今后岩溶地区矿产勘查隐伏岩溶调查提供方法借鉴。 相似文献
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在岩溶矿区钻探过程中,由于揭露、钻遇岩溶发育地层会使冲洗液在岩溶地层中流通,引起井漏、涌水等各种事故,同时揭露和沟通不同含水层,会造成初始岩溶含水系统的破坏。以贞丰县者相二金矿区为例,为避免钻孔施工对矿区内饮用水源龙井(S24)的影响,需查清其径流带在矿区的分布情况,本文针对矿区内龙井(S24)岩溶暗河出口,首先利用水文地质调查手段,初步判决岩溶发育程度、覆盖层厚度及结构,然后采用充电法和高密度电法组合进行深部探测研究,再将物探反演结果与水文、地质等资料进行综合对比分析、解释,揭示矿区内龙井(S24)岩溶暗河的空间形态、规模,指导钻探施工,后经钻探工程验证,未对龙井水(S24)造成影响,有效降低矿区勘探对浅部岩溶水系统的影响,实现了矿区从水文地质、物探勘查到钻探施工各个环节的绿色勘查。 相似文献
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铲子坪金矿为板溪群构造破碎带蚀变岩型金矿床。钻探施工中,因地层复杂、岩石坚硬及孔斜超差,严重影响着钻探效率和质量。1988年后,积极引入受控定向钻探等新技术,因地制宜、综合治理,工艺技术逐渐配套完善,取得了较好的地质成果与社会经济效益,为矿区地质工作的全面开展提供了有效的技术保证。 相似文献
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考虑核电厂地基-基础的动力相互作用,应用显式动力有限差分法分析了地震作用下极软岩、较软岩、坚硬岩上核电厂建筑结构基础的地震响应特征,比较了岩石坚硬程度对基础加速度反应谱的影响。研究表明:随着岩石坚硬程度的提高,核电厂建筑物结构基础的地震响应有增加的趋势;在周期轴上,基础处的加速度反应谱曲线会随着岩石坚硬程度的提高逐渐向短周期(高频段)方向移动。在高频段,建造于较坚硬岩石上基础结构的加速度反应谱值偏大;在中等频段,建造于较软岩石上基础结构的加速度反应谱值偏大;在低频段,岩石坚硬程度对加速度反应谱的影响不显著。 相似文献
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Ivan V. BRAGIN Georgy A. CHELNOKOV Oleg V. CHUDAEV Natalia A. KHARITONOVA Sergey V. VYSOTSKIY 《《地质学报》英文版》2016,90(1):276-284
Studied waters belong to warm(T=30-50℃),alkaline(pH=8.9-9.3),low mineralized(TDS235 mg/1)Na-HCO_3 or Na-SO_4-HCO_3 thermal waters with high content of SiO_2(up to 81 mg/l)and F(up to 3.9 mg/1),occur on modern volcano-tectonic rejuvenated areas of Eastern Sikhote-Alin orogenic belt.Low~3He concentration as well as N_2/O_2 and N_2/Ar ratios exclude influence of deep mantle fluid.New rare earth element data constrain our understandmg of water-rock interaction occurring in the water source region.Meteoric origin of waters is proved by stable isotope values varying from-71‰to-136.1‰and from-10.8‰to-18.8‰forδ~2U andδ~(18)O respectively.REE patterns reflect high pH,resultfing from water-rock interaction and oxidative conditions.Calculations of deep aquifer temperature using Na-K and quartz geothermometers show 116.8-131.1°C and 82.2-125.8℃respectively.Presence of deep faults both with abnormal thermal gradient(~45-50 K/km)define unique geochemical shape of thermal waters of Sikhote-Alin,area,where no present volcanic activity is registered. 相似文献
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M. D. Sharma 《Journal of Earth System Science》2004,113(2):247-257
Three dimensional scattering of near-field is studied for dilatation and rotation in the time domain. The perturbation method
is applied to solve the equation of motion for the first order scattering from a weak inhomogeneity in an otherwise homogeneous
medium. The inhomogeneity is assumed close enough to the point source so that the near-field intermediate wave is dominating
over the far-field sphericalP andS pulses. The integral expressions are derived to relate dilatation and rotation of scattering to the radial fluctuations of
velocities and density in the inhomogeneity. These integrals are solved to calculate the strains of scattering from (a part
of) an inhomogeneous spherical shell of arbitrary curvature. Variable curvature may allow the shape of inhomogeneity volume
element to change uniformly from spherical to rectangular. Rotation of scattering from a spherical shell is independent ofP wave velocity inhomogeneity. Dilatation of scattering does not involveS wave velocity inhomogeneity but its gradient. The back scattering results are obtained as a special case. Strains are computed
numerically, for hypothetical models to study the effects of various parameters viz., velocity inhomogeneity, distance of
source from inhomogeneity and from receiver, and thickness of inhomogeneity. The curvature of the spherical shell is varied
to study the effects of the shape of inhomogeneous volume element on scattering. 相似文献
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地震次生地质灾害风险评估集对态势分析 总被引:2,自引:0,他引:2
5.12四川汶川8级强震引发了大量次生地质灾害,加剧了灾情并严重影响抗震救灾。地震次生地质灾害受多重因素制约,其孕育与致灾过程具有不确定性。利用集对分析原理与方法,对地震次生地质灾害进行同异反态势分析,拟定了风险评估的集对分析同一度、差异度、对立度等指标体系的构建原则与赋值标准,对承灾体系统的不确定性及其作用作了刻画与分析,建立了不同风险分区代表性的集对分析联系度表达式,为地震灾害研究提供了可资借鉴的新思路和技术方法。 相似文献
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下扬子区三叠纪古地理演化 总被引:2,自引:2,他引:0
下扬子区在三叠纪期间接受了早-中三叠世海相碳酸盐沉积、中-晚三叠世海陆交互相和陆相湖沼沉积.沉积相带的空间分布和古地理格局的变迁明显地受到区域构造的控制.区内盆地发育与演化是在华南板块与扬子板块、扬子板块与华北板块相互作用的背景下进行的.早-中三叠世末期的印支运动是下扬子区构造-古地理格局改变的决定性因素,使下扬子海盆闭合,沉积类型由海相沉积变为陆相沉积.下扬子区三叠纪古地理的演化特征也为板块碰撞提供了沉积证据. 相似文献
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Isothermal thermogravimetric experiments have been carried out to determine the reaction kinetics of the dehydration processes
in fuller's earth, a natural Ca-montmorillonite. Dehydration in swelling clays is a complex reaction, and analysis of the
thermogravimetric data using empirical rate equations and time-transformation analysis reveals that the nature of the rate
controlling mechanism is dependent upon both the temperature regime of the sample as well as the extent of reaction. For fuller's
earth, we find that the dehydration kinetics are dominated by a nucleation and growth mechanism at low temperatures and fractions
transformed (stage I), but above 90 °C the last stages of the reaction are diffusion controlled (stage II). The activation
energy for dehydration during stage I is around 35 kJ · mol−1, whereas the removal of water during stage II requires an activation energy of around 50 kJ · mol−1. These two stages of dehydration are associated with primary collapse of the interlayer (stage I) and movement of water that
is hydrated to cations within the interlayer (stage II).
Received: 28 August 1998 / Revised, accepted: 27 January 1999 相似文献