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61.
面积平衡法与川东大池干推覆带区域滑脱面预测 总被引:3,自引:3,他引:0
本文详细介绍了面积平衡法的原理与方法,并将该方法应用于川东大池干构造的解释。利用面积平衡法,本文预测出在该地区可能有三个较大的区域滑脱面,它们分别位于3.53km处的中三叠统(由石膏、盐岩和泥页岩组成),7.79km处的下寒武统(由页岩、石膏和岩盐层组成),以及8.67km处的下寒武统(由页岩、石膏和岩盐层组成)地层之中。根据以上滑脱面的分析结果,作者认为大池干构造可以解释为滑脱褶皱和断层转折褶皱两种成因模式。在滑脱褶皱模式中,主滑脱面为8.67km处的非能干层;在断层转折褶皱模式中,该地区被认为具有上下两个滑脱面,其上滑脱面为3.53km处的非能干层,而其下滑脱面为7.79km处的非能干层。两种模式所对应的面积深度直线都具有较好的相关性,表明两种构造解释都具有内部岩层一致性,剖面达到平衡,故具有相对的合理性。 相似文献
62.
63.
This paper introduces a new method for GPS signal acquisition, which is based on the repeatability of successive code phase
measurements and the M-of-N search algorithm. The performance of the proposed method in terms of probability of signal detection
is similar to that of traditional methods, except that the calculation of the probability of detection does not rely on the
noise distribution or the Carrier-to-Noise ratio (C/N0). The code phase repeatability-based method is presented along with equations for probability of detection and probability
of false detection. If the distribution of the noise is known, it also provides an estimate of the C/N0. The proposed method is illustrated for coherent and non-coherent acquisition and C/N0 estimation. 相似文献
64.
对河南省栾川县大练沟泥石流治理的经验总结 总被引:1,自引:0,他引:1
随着国民经济迅速发展,对矿产资源的需求日益增多,20世纪七、八十年代的开采只追求产量和经济效益,而忽视了对环境的保护,开采的矿渣乱排乱放现象非常严重,严重破坏了环境,象这样的矿山在全国各地有很多,随着时间的发展,松散堆积的矿渣在洪水的作用下顺着沟道倾泻而下,形成泥石流,对下游的人民生命财产造成严重的破坏和威胁,矿山泥石流逐步发展,进入发展期和活跃期,必将造成更大的危害。因此对这样的泥石流沟进行研究和治理是很有必要的。在对河南省栾川县大练沟泥石流的治理过程中,得出以下几点体会,现总结归纳出来,希望对类似泥石流沟的治理提供借鉴。 相似文献
65.
三维可视化及物探新技术在矿山接替资源勘查中的应用——以铜陵狮子山矿田为例 总被引:1,自引:0,他引:1
在矿山发现和勘查过程中往往积累了大量地质、物探等资料,随着地质体三维可视化和物探新处理方法的发展,利用这些方法对已有资料进行深度挖掘与开发可以提炼出新的有利找矿的信息,避免工作量的重复投入,可为矿山接替资源勘查提供有力的技术支持.本研究以铜陵狮子山矿田为例,收集了其勘探阶段积累下来的地质钻探及物探资料,采用地质体三维可视化建模技术对这些资料进行了二次处理,建立了冬瓜山铜矿的三维矿床模型.在可视化环境下,分析了矿体与各成矿地质要素之间的关系,结合新处理方法对已有重磁资料再处理获取的信息,圈定出了寻找同类矿床的靶区一前冲靶区,并采用EH-4等物探方法进行了验证,通过钻探验证表明,采用三维可视化、物探处理新方法对已有资料进行深度挖掘与开发,不但可以为矿山接替资源勘查提供找矿信息,还能节约大量时间和资金. 相似文献
66.
Akinobu Miyakoshi Takeshi Hayashi Atsunao Marui Yasuo Sakura Shinichi Kawashima Masafumi Kawai 《International Journal of Earth Sciences》2008,97(2):401-411
Information on the distribution of subsurface temperature and hydraulic heads at 24 observation wells in and around the Tokyo
Lowland, the eastern part of the Tokyo Metropolitan area, were examined to make clear the relationship between groundwater
and the subsurface thermal environment in the urban area. Minimums in temperature–depth logs due to subsurface temperature
increasing at shallow parts were recognized in 21 wells. This fact shows subsurface temperature is affected by ground surface
warming in almost all of this area. Deeper than minimums, where the effects of surface warming became relatively small, regional
variation is observed as follows: high temperatures are shown in the central part to the southern part, and low temperatures
shown in the inland to eastern part. The high temperature area corresponds to an area where the lower boundary of groundwater
flow is relatively shallow. This area corresponds also to an area with severe land subsidence resulting from excessive groundwater
pumping. It is considered that this high temperature area is formed by the effects of upward groundwater flow affected by
hydrogeological conditions and pumping. On the other hand, a comparison between past data (1956–1967) and present data (2001–2003)
revealed widespread decreasing temperature in the inland area. This is explained by downward groundwater flow based on an
analysis of temperature–depth logs. This fact suggests that subsurface temperature is not only increasing from the effects
of surface warming but also decreasing from the effects of groundwater environment change due to pumping. 相似文献
67.
分析了浅埋藏砂岩的成岩环境,并从岩石学、矿物学、同位素及质量平衡估算方面论证硅质碎屑砂岩中的胶结物主要来源于砂岩浅埋藏期间的地下水,进而分析浅埋藏带内地下水的流动机制及早期胶结作用对晚期成岩作用的影响。 相似文献
68.
葛焕称 《地震学报(英文版)》1995,8(1):57-63
OnsomeproblemsofseismiccrustalphaseHuan-ChengGE(葛焕称)(SeismologicalBureauofJiangsuProvince,Nanjing210014,China)Abstract:Inthis... 相似文献
69.
本文在系统分析静海台井下地震记录图的基础上,发现并解决了具有一定实际和理论意义的两个问题:其一是证明了最初误认为是干扰的“双脉冲”图形实际上均是微地震。从而指出研究静海周围地区的地震活动性应考虑微震活动问题。其二确认静海周围地区微震波形的4个主要震相是P、PP、S和SS,并对地面反射波PP和SS能够观测到的条件作了初步分析,其结果进一步说明井下地震记录较之地面记录更为“逼真”,复杂和丰富。 相似文献
70.
We theoretically study the scattering ofP, SV andSH waves by a zonal distribution of cracks, which simulates a fault fracture zone. An investigation is conducted how the geometrical properties of the crack distribution and the frictional characteristics of the crack surface are reflected in the attenuation and dispersion of incident waves, as well as in the amplitudes of the transmitted and reflected waves from the zone. If the crack distribution within the fault zone changes temporally during the preparation process of the expected earthquake, it will be important for earthquake prediction to monitor it, utilizing the scattering-induced wave phenomena.We consider the two-dimensional problem. Aligned cracks with the same length are assumed to be randomly distributed in a zone with a finite width, on which elastic waves are assumed to be incident. The distribution of cracks is assumed to be homogeneous and sparse. The crack surface is assumed to be stress-free, or to undergo viscous friction; the latter case simulates fluid-filled cracks. The opening displacement of the crack is assumed to be negligibly small. The idea of the mean wave formalism is employed in the analysis, and Foldy's approximation is assumed.When the crack surface is stress-free, it is commonly observed for every wave mode (P, SV andSH) that the attenuation coefficientQ
–1 peaks aroundka1, the phase velocity is almost independent ofk in the rangeka<1 and it increases monotonically withk in the rangeka>1, wherek is the intrinsicS wavenumber anda is the half length of the crack. The effect of the friction is to shift the peak ofQ
–1 and the corner of the phase velocity curve to the low wavenumber range. The high wavenumber asymptote ofQ
–1 is proportional tok
–1 independently of model parameters and the wave modes. If the seismological observation thatQ
–1 ofS waves has a peak at around 0.5 Hz in the earth's crust is combined with our results, the upper limit of crack size within the crust is estimated about 4 km. The information regarding the transmitted and reflected waves, such as the high wavenumber limit of the amplitude of the transmitted wave etc., allows estimation of the strength of the friction. 相似文献