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华北地区人工地震测深震相与地壳结构研究 总被引：27，自引：1，他引：27
主要讨论了华北地区人工地震测深中的４个（Ｐ＿ｇ，Ｐ＿ｃ，Ｐ＿ｍ，Ｐ＿ｎ）常规震相以及它所反映的构造和物性特征，这些震相反映了地壳上地幔不同层位的构造形态以及速度和速度梯度结构在纵横向的变化。还重点研究了华北地区的奇异震相以及反映在构造上的特殊性和重要意义，一些剖面局部区域的某些震相显示在视速度、振幅和出现区间等方面的异常，反映了该区域在构造上的特殊性，而这些特殊性往往与地震的孕育、发生以及矿产资源的潜在构造背景有着密切的关系 相似文献
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根据部分地区的地震测深结果，并结合前人所做的工作，使用数理统计方法建立了地壳厚度（Ｈ＿Ｍ）、重力观测值（△ｇ）、岩石加权平均密度（ρ）和纵波速度（Ｖｐ）之间的经验公式．以重力场和二维在速度模型为基础．编制出哈萨克斯坦和邻近区域的地壳基底构造等深图，并且推广到缺少深部地震剖面资料的造山地带。按照地壳基底的构造特征可大致分为三种类型，它们分别对应于地震活动区、非活动区和过渡带，反映出哈萨克斯坦和邻区的莫霍面起伏形态和理藏深度，为地震区划综合研究提供了基础资料． 相似文献
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鉴于当前国际上关于自转微椭、非均匀地球（ＳＲＥＨＩ）的固体潮汐响应的结果之间存在明显分歧，特别是Ｌｏｖｅ数ｋ及重力潮汐因子δ对纬度的依赖情况截然不同，本文借助于摄动法与张量正则分量的广义球谐展开建立起来的侧向非均匀、自转微椭、粘弹地球的潮汐模拟理论，计算了ＳＲＥＨＩ地球的潮汐形变及相应的引力位变化．结果表明，描述径向位移的Ｌｏｖｅ数的纬度依赖部分系数ｈ＿＋与球对称部分ｈ＿０＋δｈ＿０之比不大于１．０‰；对Ｏ＿１波为０．２７‰；对Ｍ＿２波为０．１９‰；对Ｍ＿３波为０．４９‰；对Ｍ＿４波为０．８８‰．描述地球引力位变化的Ｌｏｖｅ数的纬度依赖部分系数ｋ＿＋与球对称部分ｋ＿０＋δｋ＿０之比小于３．０‰；对Ｏ＿１波为２．６７‰；对Ｍ＿２波为１．８９‰；对Ｍ＿３波为２．２４‰；对Ｍ＿４波为２．７０‰． 相似文献
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用｛Ｙ＿Ｋ｝Ｋ＝１，２，…，ｎ表示量Ｙ的巳有记载，当Ｙ＿Ｋ与Ｋ相关较强时，有些文章中就由Ｙ关于序号Ｋ的回归方程，取作为Ｙ在下一步的预测或预测的过渡值。本文对这种按顺序回归的回归系数进行剖析，得知：ｎ稍大时，前期与中期的数据Ｙ＿Ｋ在序回归中起主要作用，代表新近信息的后期Ｙ＿Ｋ作用甚小，因而回归值在尾端与实际值有较大偏离。加之，系数ｂ只是增量Ｙ＿Ｋ－Ｙ＿（Ｋ－１）的一种加权平均，以ｂ为步长外延未能刻划Ｙ＿（ｎ＋１）－Ｙ＿ｎ的起伏，故地震预测中应用序回归难有良好实效。 相似文献
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以具有代表性的正旋回砂砾岩储层中，８种不岩性的典型样品，在５种含油（气）水饱和状态下测试了纵、横波速度（ＶＰ和ＶＳ）与有效覆盖压力变化关系曲线，结果表明：（１）ＶＰ和ＶＳ与ΔＰ呈指数递增，ＶＰ和ＶＳ随ΔＰ变化在低压范围比高压范围更敏感，而ＶＰ比ＶＳ的灵後工高。（２）同一状态下，同一非均质单层内的岩性变化范围控制了不同的ＶＰ－ΔＰ，ＶＳ－ΔＰ曲线族的宽度，岩性由细到粗，ＶＰ－ΔＰ曲线由低高变化，含钙 相似文献
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本文对强震前震源系统的调制比ｒ＿ｍ和调制比异常面积Ｓｒ＿ｍ随时间变化的起伏加剧现象进行回顾性研究，得到下列研究结果：（１）强震前近源区以及中强震前近源区大多出现调制比ｒ＿ｍ的起伏加剧，并大多在起伏频次达三次时有大震或中强震发生。（２）大多数中、强地震前ｒ＿ｍ异常面积Ｓｒ＿ｍ围绕震源区呈现由小至大、由大至小的过程，因此引入最小异常面积Ｓｒ＿（ｍｉｎ）和最大异常面积Ｓｒ＿（ｍａｘ）之比γ作为中、短期预报指标，根据统计得到异常指标［γ］如下式某些震例在震前出现异常面积Ｓｒ＿ｍ起伏的加剧过程，初步认为是震源区周围调整单元调整能力较差导致的结果。（３）ｒ＿ｍ、Ｓｒ＿ｍ起伏加剧开始时间与震级有关，震级愈大，起伏加剧出现愈早。根据半年步长逐月滑动得到的ｒ＿ｍ－Ｔ图，起伏加剧开始至发震的时间与震级Ｍ的统计，得到如下关系（Ｔ以月计）Ｍ＝４．２９＋０．１１Ｔ（４）强震前场区异常一般呈现随机异常型、波动型和衰减型三种。若场区某统计区出现ｒ＿ｍ的三次起伏加剧时，说明该统计区未来有强震发生。（５）由自治系统和非自治系统原理初步解释了震前震源区周围调整区调制比ｒ＿ｍ及调制比异常面积Ｓｒ＿ｍ起伏现象的周期特征。 相似文献
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本文尝试用ＣＤｓＮ的ＩＰｚ分量强震记录来测定谱震级。通过对测出的谱震级ｍ＿（Ｔ）与体波震级ｍ＿（Ｂ）、ｍ＿（ｂ）的相关分析，得出其反映震源特性的峰值，出现在周期Ｔ＝１秒左右。此外，谱震级还有随周期而变化的特性。根据谱震级与能量的关系，推导了它的通用形式为ａｍ＿（Ｔ）＝ｌｏｇ（Ｅ／Ｅ０）（式中ａ＝２，ｌｏｇＥ＿０＝５．６）。它的最高震级为９．６级。运用谱震级的通用形式对本文测定的４个谱震级进行检验，结果表明它比传统方法测定的ＩＰｚ分量体波震级ｍ＿（Ｂ）系统偏小０．３１级。因谱震级是扣除了介质滞弹性吸收影响后的产物，故这种偏差是比较合理的。 相似文献
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在具有代表性的正旋回砂砾岩储层中，８种不同岩性的典型样品，在５种含油（气）水饱和状态下测试了纵、横波速度（Ｖｐ和Ｖｓ）与有效覆盖压力（△Ｐ）变化关系曲线。结果表明：（１）Ｖｐ和Ｖｓ与△Ｐ呈指数递增，Ｖｐ和Ｖｓ随△Ｐ变化在低压范围比高压范围更敏感，而Ｖｐ比Ｖｓ的灵敏度高。（２）同一状态下，同一非均质单层内的岩性变化范围控制了不同的Ｖｐ－△Ｐ，Ｖｓ－△Ｐ曲线族的宽度。岩性由细到粗，Ｖｐ－△Ｐ曲线由低向高变化，含钙、含砾粗砂岩的Ｖｐ－△Ｐ曲线处于曲线族的上界，砾状砂岩的Ｖｐ－△Ｐ曲线低于含砾粗砂岩的Ｖｐ－△Ｐ曲线。Ｖｓ－△Ｐ曲线也有上述规律。（３）同一样品，研究５种不同饱和度状态下的Ｖｐ－△Ｐ和Ｖｓ－△Ｐ曲线，发现无论压力条件如何，波速与饱和度均呈线性关系。（４）在同一的非均质单层内，Ｖｐ－△Ｐ，Ｖｓ－△Ｐ变化曲线随着含油、气、水饱和状态的不同具有明显的分带性。气饱和Ｖｐ－△Ｐ曲线族在形态及幅度变化上明显区别于油、水饱和状态，束缚水、残余油状态的Ｖｐ－△Ｐ曲线族，Ｖｓ－△Ｐ曲线也有上述规律。气饱和状态的Ｖｐ和Ｖｓ随△Ｐ变化的敏感度高于油、水饱和状态，气饱和状态的Ｖｐ随△Ｐ变化的敏感度高于Ｖｓ。 相似文献
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THE USE OF A GAMMA LOGGER TO DELINEATE GLACIAL AND BEDROCK STRATIGRAPHY IN SOUTHWESTERN OHIO 总被引：1，自引：0，他引：1
Abstract. An evaluation was made of the usefulness of the gamma-ray logger in delineating glacial-drift and bedrock stratigraphy in southwestern Ohio. The logger was useful in delineating gross stratigraphic units in a glacial outwash aquifer. The gamma log also provided a clearer indication of the clay content of sand and gravel units than did the driller's log.
On the uplands, away from the valleys filled with glacial outwash, the logger could not be used to locate the thin, poorly-sorted, interstadial sand and gravel deposits between thicker till sheets. It could, however, be used to distinguish formational contacts in the upper Cincinnatian Series. 相似文献
On the uplands, away from the valleys filled with glacial outwash, the logger could not be used to locate the thin, poorly-sorted, interstadial sand and gravel deposits between thicker till sheets. It could, however, be used to distinguish formational contacts in the upper Cincinnatian Series. 相似文献
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Submersible data loggers are widely used for groundwater monitoring, but their application often runs the risk of hardware and data loss through vandalism or theft. During a field study in India, the authors of this article experienced that well locks attract the attention of unauthorized persons and do not provide secure protection in unattended areas. To minimize the risk of losing data loggers, a cheap and simple solution has been invented to hide the instruments and associated attachments below the ground surface, inside observation wells. It relies on attaching the logger to a length of small-diameter pipe that is submerged at the bottom of the well, instead of attaching it to the top of the well. The small-diameter pipe with the logger is connected to a small bottle containing a magnet that floats on the water surface of the well and can be recovered using another bottle also with a magnet. A logger that is concealed in this way is difficult to detect and access without knowledge of the method and adequate removal tools. The system was tested and successfully applied for monitoring shallow observation wells at three field sites in Greater Delhi, India. 相似文献
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A wide variety of sampling programmes may now be considered practical with the recent developments in data logger and water sampler technology. In ephemeral systems the water sampler remains idle for long periods between events. Two approaches are described which overcome the problems of sampling in ephemeral systems: short interval time dependent sampling (TDS) and automated flow proportional sampling (FPS). Both approaches utilize the data logger's ability to perform intermediate operations on incoming data to control the initiation of water sampling. The logger programs are described and allow many recorder/water sampler units to be controlled from one device. The relative merits of the two approaches are discussed in terms of experimental requirements and data precision. 相似文献
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A new concept in recording data from a large network of transducers in the field is described. Each transducer is equipped with an addressable switching unit enabling parallel connection by a single four wire cable and sequential interrogation from a micro-computer controlled data logger. A simple water level transducer suitable for both large stilling wells and piezometers, which returns an audio frequency signal with pulse width proportional to water level, is described. The use of audio frequency signals enables telephone grade circuits to be used and avoids many of the problems associated with direct current signals, whether current or voltage, commonly used at present. A field installation of 30 piezometers, a tipping bucket raingauge, a weir-stage recorder and logger controlled water sampler is described and examples given of the data collected from a single piezometer transect during a major storm event. 相似文献
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Detailed information on vertical variations in hydraulic conductivity (K) is essential to describe the dynamics of groundwater movement at contaminated sites or as input data used for modeling. K values in high vertical resolution should be determined because K tends to be more continuous in the horizontal than in the vertical direction. To determine K in shallow unconsolidated sediments and in the vertical direction, the recently developed direct-push injection logger can be used. The information obtained by this method serves as a proxy for K and has to be calibrated to obtain quantitative K values of measured vertical profiles. In this study, we performed direct-push soil sampling, sieve analyses and direct-push slug tests to obtain K values in vertical high resolution. Using the results of direct-push slug tests, quantitative K values obtained by the direct-push injection logger could be determined successfully. The results of sieve analyses provided lower accordance with the logs due to the inherent limitations of the sieving method. 相似文献
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OLEG F. VASILIEV 《水文科学杂志》2013,58(2):129-134
Abstract A combined snowfall and snowmelt gauge has been designed and tested to meet the particular conditions commonly found in the British Isles, where snow covers tend to be relatively shallow and short-lived. Current measurement techniques in Britain tend to underestimate both frequency and amount of snowfall. The gauge identifies and measures snow cover by a hydraulic weighing system biased to shallow covers. Snowmelt and rainfall are measured via a central drainage system. Both measurements can be attached to a data logger and could be used in a telemetry network. 相似文献
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新型数字强震仪关键技术分析 总被引：1，自引：0，他引：1
新型强震仪采用高速信号处理器为控制核心,24位∑- △A/D转换器与数字滤波器构成的3通道信号采集系统.仪器采用大容量CF卡记录采集数据,具有TCP/IP协议的网络通信接口,内置GSM通信模块,内置嵌入式网页服务器,可以通过浏览器与发送中文短信的方式对仪器进行监控.详细分析了仪器所采用的烈度算法与触发滤波器的特性和设计... 相似文献
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广州海洋地质调查局用德国产的微型温度传感器和自行研制的重力取样器组装成海底热流探针,并用该设备在中国南海北部开展了海底热流测量,这是国内首次独立开展此项工作,也是我国海洋地质和地球物理调查技术方法的新尝试.通过实测数据分析以及与1985年中美合作获得的西沙海域地热流测量剖面数据对比,表明测量数据可靠并具有良好的一致性.此项工作的成功,将有助于地热流测量工作的深入开展,进而提高我国海底天然气水合物的勘探和海洋地质基础研究的水平. 相似文献
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Laboratory and field experiments demonstrated that solid state pressure transducers are accurate and reliable devices for frequent measurements of soil suction. However, each transducer had to be individually calibrated before use and a hanging column procedure designed for this purpose is described. Analysis showed that each transducer had a linear response and that environmental conditions such as temperature had minimal influence. Twenty four tensiometers with pressure transducers were intalled in a forest soil to test their operation and their output was monitored by a data logger. An example of soil suction results measured during four storms is given to demonstrate their stability and their rapid response. The transducers were found to perform accurately and were only affected by temperatures below 0°C. 相似文献