唐山地震前后水氡变化率动态图象的特征分析   总被引：1，自引：0，他引：1       下载免费PDF全文

张素欣  王吉易  郑云贞 《地震工程学报》1998,20(3):22-26

讨论了唐山地震前后水氡变化率动态图象的时空演化特征．用水氡月均值的变化率做参量,绘制每月的变化率平面等值线图,得到水氡的变化率动态图象．研究表明,唐山地震前震中周围出现水氡变化率≥０．０６的异常特征区．异常特征区的面积具有“扩展—收缩”的特点,并显示出阶段性．  相似文献   

TCM-90现场试验台风能量频散波列特征   总被引：13，自引：5，他引：8  

徐祥德  陈联寿  解以扬  亢迪 《气象学报》1998,56(2):129-138

采用ＴＣＭ－９０（台风运动－９０）台风现场科学试验资料,对台风ＦＬＯ,ＥＤ个例进行了诊断分析,并做了有关数值试验研究。分析研究结论揭示了台风涡旋作为一动力、热力强迫源或ＣＩＳＫ不稳定结构,其与环境场相互作用可激发出动能频散波列;台风扰源通过频散机制可构成类似２维Ｒｏｓｓｂｙ波的经向波列;台风涡旋的移动路径与上述能量传播特征有一定的相关关系。  相似文献   

德国大陆科学钻探计划的测井成就   总被引：3，自引：2，他引：1  

王祝文  李舟波 《世界地质》1998,17(2):67-72

德国大陆科学钻探计划（ＫＴＢ）经过８年多的努力,钻探了先导孔（ＶＢ）和主孔（ＨＢ）两口举世瞩目的科学钻孔。地球物理测井技术在这个计划中起到了不忽视的作用,本文简要介绍了在德国大陆学科钻探计划（ＫＴＢ）实施过程中,地球物理测井所取得的主要成就。  相似文献   

河东煤田中南部煤层气地质及其勘探开发前景   总被引：1，自引：0，他引：1  

韦重韬  桑树勋 《华北地质矿产杂志》1998,13(3):243-248

通过对煤层生,储,盖,构造演化史及水文地质特征的研究,讨论了研究区煤层气开发的前景。结果表明：区内主要煤层具有良好的生气潜能,储集和盖层封盖性能,构造演化和水文地质条件是影响煤层气富集的主要因素;煤层气藏的浅部区主要以中小规模构造圈闭气藏的形式存在,深部区的较大规模的水动力圈团或复合圈闭气藏;柳林西南煤层６００～１５００ｍ埋深区域是目前进行进一步开发工作的首选区域。  相似文献   

Exploration of an alluvial aquifer in Oman by time-domain electromagnetic sounding   总被引：1，自引：0，他引：1  

M. E. Young  R. G. M. de Bruijn  A. Salim Al-Ismaily 《Hydrogeology Journal》1998,6(3):383-393

 One-third of the population of Oman depends upon groundwater extracted from the alluvium of the Batinah Plain, on the coast of the Gulf of Oman. Deep geophysical exploration techniques were used to determine the depth and nature of the alluvium and the boundaries of the aquifer. The base and structural controls of the alluvial basin at its contact with Tertiary marine sediments and Cretaceous ophiolite were mapped with seismic reflection data, recorded originally for oil exploration. The base of the alluvium dips northward from the foothills of the Northern Oman Mountains, reaching a maximum depth of 2000 m at the coast. The varying facies of the alluvium are grossly characterised by different, overlapping ranges of electrical resistivity, depending largely on the clay content and degree of cementation. Resistivities near the coast are reduced by saline intrusion. These variations of resistivity were mapped with time-domain electromagnetic sounding along 400 km of profile, to distinguish among the three zones of the alluvial aquifer. The wedge of saline intrusion was also delineated, up to 10 km from the coast. The thickness of the saturated gravel aquifer ranges from 20–160 m in an area greater than 600 km². Received, April 1997 · Revised, January 1998 · Accepted, April 1998  相似文献   

长江三峡地区地球物理异常带地表地质特征     

王清云  李安然  张秋文 《大地测量与地球动力学》1998,(1)

通过长江三峡地区（巴东－宜昌段）水系发育、航卫片判读、野外地质调查等方面的研究,认为沿长江北西西向地球物理异常带在地表没有相应的特殊地质构造显示。中、新生代沉积盖层中未发现规模较大的北西－北西西向断裂通过,地表上这一走向的线性破裂或裂隙密集带及其他相关变形也不甚发育。因此,地下深处与地球物理异常带相对应的基底断裂至少中生代以来没有明显活动。  相似文献   

勘探地球物理层析成像软件系统及其应用   总被引：2，自引：1，他引：1  

朱介寿  严忠琼  曹俊兴  张雪梅 《物探与化探》1998,22(2):90-98

本文对人工场源激发的地震波、声波、电磁波及电阻率分布而重建地下物理参数图像的理论、正反演算法、计算机软件、实验室超声波模型实验、电阻率实验等做了大量的研究,完成了由Windows95支持的勘探地球物理层析成像软件系统的研制,并介绍了三个勘探应用实例。  相似文献   

吉林夹皮沟本区金矿床成矿预测     

毛德宝  沈保丰  李双保  李俊建 《华北地质》1998,21(4):2

本文概要介绍了笔者在夹皮沟本区开展成矿预测的研究成果。通过化探原生晕、伽马能谱、变频缴电法测量等找矿方法的综合研究,认为夹皮沟本区仍然具有较大的找矿远景,提出41个异常点段,预测金储量约6吨。  相似文献   

新生代浮游有孔虫整体变化趋势     

郝治纯  雷新华 《现代地质》1990,4(3):1-12

新生代浮游有孔虫在确定地层时代和推断古沉积环境等方面有着极其重要的实用价值,本文利用新生代浮游有孔虫数据库,对其中的属种资料进行了大量的分析和总结,初步了解了新生代浮游有孔虫整体特征的变化趋势及其在各地史时期中的面貌,使我们有可能建立一种以浮游有孔虫分类特征为基础的“模式”。这样,我们不仅把握了新生代浮游有孔虫的宏观特征,而且有可能找到一种只要对某些特征组合面貌进行判断即可大致确定地层时代的快速方法。  相似文献   

The Microphysical Characteristics of Wintertime Cold Clouds in North China     

Xuexu WU  Minghuai WANG  Delong ZHAO  Daniel ROSENFELD  Yannian ZHU  Yuanmou DU  Wei ZHOU  Ping TIAN  Jiujiang SHENG  Fei WANG  Deping DING 《大气科学进展》2022,39(12):2056-2070

The microphysical characteristics of wintertime cold clouds in North China were investigated from 22 aircraft observation flights from 2014 to 2017, 2020, and 2021. The clouds were generated by mesoscale weather systems with little orographic component. Over the mixed-phase temperature range (–40°C to 0°C), the average fraction of liquid, mixed-phase, and ice cloud was 4.9%, 23.3%, and 71.8%, respectively, and the probability distribution of ice mass fraction was a half-U-shape, suggesting that ice cloud was the primary cloud type. The wintertime mixed-phase clouds in North China were characterized by large cloud droplet number concentration, small liquid water content (LWC), and small effective diameter of cloud droplets. The main reason for larger cloud droplet number concentration and smaller effective diameter of cloud droplets was the heavy pollution in winter in North China, while for smaller LWC was the lower temperature during flights and the difference in air mass type. With the temperature increasing, cloud droplet number concentration, LWC, and the size of ice particles increased, but ice number concentration and effective diameter of cloud droplets decreased, similar to other mid-latitude regions, indicating the similarity in the temperature dependence of cloud properties of mixed-phase clouds. The variation of the cloud properties and ice habit at different temperatures indicated the operation of the aggregation and riming processes, which were commonly present in the wintertime mixed-phase clouds. This study fills a gap in the aircraft observation of wintertime cold clouds in North China.  相似文献