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闽南地区综合防震减灾示范工程厦门地震台地震前兆观测(地形变学科)数字化改造基础工程建设工作于4月上旬完工,近日通过福建省地震局验收。厦门地震台地震前兆观测(地形变学科)数字化改造工程的建设目标是将厦门地震台建设成为我国东南沿海地区地壳形变观测基本台。在2000年度,厦门地震台将配备安装目前国内最先进的数字化ＳＳＹ型伸缩仪;ＤＳＱ型水管仪,ＶＳ型垂直摆倾斜仪、ＤＺＷ微伽重力仪和德国生产的具国际先进水平的ＤｉＮｉ11电子水准仪,目前已签订完成了全部仪器的订购合同并已预付首期合同款。这次厦门地震台地震前兆观测数字化改… 相似文献
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本文主要介绍我省地震地下流体前兆观测台网的现状 ,并对已完成地下流体前兆观测“十五”数字化改造的台站和测项进行分析 ,阐述了地下流体数字化改造中存在的问题。 相似文献
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目前在地震前兆的观测方面，普遍趋向于将最突出的地震前兆根据可能有的预警时间归类于一种地震发生的模型．例如，Rikitakc(1987)最近收集了418个日本的地震前兆异常，并按照前兆时间作了分类．虽然在可靠性和统计意义上变动很大，但是这种经验观测至少可以分出4种截然不同的类型， 相似文献
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为地震地下水前兆观测技术实现数字化和综合化这一发展目标 ,性能先进的数字化观测仪器和功能优良的综合观测平台是相辅相成的两个基本方面。本文在分析已有综合观测体系模式的基础上 ,应用最新研究成果 ,提出了新一代综合观测模式 ,给出了单井综合观测平台结构设计。该平台在与地下水各测项的数字化观测仪器对接后 ,可实现静水位、水化学和水温三者均处在理想观测状态条件下的自动化单井综合观测 相似文献
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《地壳构造与地壳应力文集》2003,(1)
一、引言 2001年11月14日17时26分,在新疆、青海交界的昆仑山口西(北纬36.2°,东经90.9°)发生了8.1级地震。这是继1950年8月15日西藏察隅8.6级地震后,中国大陆发生的最大地震。昆仑山口西8.1级地震前,首都圈及华北北部部分地温测点观测到了明显的前兆异常和同震效应。本文对这些前兆异常和同震效应进行了初步分析和研究,这对进一步分析研究地温观测资料的前兆特征,提高地温观测资料预报地震水平是十分有益的。 相似文献
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数字化形变台站日常下载、处理直至管理数据,都应用《数字化通讯控制软件》、《形变前兆台站(网)数据处理系统》及《形变前兆数据库服务软件(台站版)》等三个软件交互进行,在实际使用过程中会遇到一些棘手的问题。本文结合我台的观测工作的实践,总结经验,以供台站同行共享。 相似文献
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经过约25个世纪的时间，人们观察到了大量的地震前兆现象，并收集和记录了有关的资料，有的工作是专门的人员完成的：有的是由于偶然的机会或者由间接的原因形成的。最近120年以来，这方面的资料得到了系统的收集；近30年来，这项工作和深入地研究与地震发生的物理化学现象相结合，成了地震预报应用研究的一项工作。引入时间、空间的概念，重新建立了详细记录地震、地震前兆和地震预报研究的主要方法。在地震前兆的研究中，对起促进作用和阻力作用的科学上和经济上的限定因素已经有所考虑及评论。 相似文献
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甘肃西秦岭新生代钾霞橄黄长岩中的球状分凝体及地幔流体反演 总被引：1，自引：0，他引：1
地幔流体在地质过程中的作用日益受到人们的重视,成为地球科学研究的一个前缘课题。提供了甘肃西秦岭新生代钾霞橄黄长岩中各种形态分凝体详细的岩相学、矿物学和矿物化学的资料,对分凝体的性质、深部地幔流体的成分及成因机制进行了讨论。研究表明,钾霞橄黄长岩中分凝体是软流圈地幔流体活动的记录,其成因机制与岩浆作用对软流圈的开放和软流圈上涌的条件下,原生钾霞橄黄长岩浆的分异作用（特别是液态不混熔作用）,以及岩浆的抽提作用、动态熔融作用等综合作用有关。 相似文献
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The generation of a near-global set of orthometric height data derived from satellite altimetry has allowed for the first time an independent evaluation of the accuracy of existing Global Digital Elevation Models (GDEMs) on a near-global scale. This paper presents results from an intercomparison of GLOBE v1, GLOBE β and JGP95E with altimeter based datasets derived from the ERS-1 geodetic mission, together with ERS-1 and ERS-2 35 day data.One result of this research is the identification of common error signatures, where correlated height differences are seen to exist between the altimeter data and several of the DEMs. The ability to identify such erroneous ground truth data using altimetry facilitates the improvement of these global and regional models. Having targetted regions where the height data are inaccurate, it enables examination of these data for mis-registration and reference datum errors, which can then be corrected using altimetry derived heights. 相似文献
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K Narahari Rao 《Journal of Earth System Science》1995,104(2):257-271
It is observed that the daily mean temperature of the soil is linear with depth and the variation of the temperature is sinusoidal
with a period of a day. Based on these observations the one-dimensional heat conduction equation for the soil can be solved
which gives the amplitude and phase variation of the temperature wave with depth. Given the temperature data at three levels
below the surface, the amplitude and phase variation and hence the surface temperature variation over the day are estimated.
The daily mean temperature of the surface is estimated from linear extrapolation of the daily means at the three levels below
the surface. Estimated values of soil thermal diffusivity show a subtantial change after sudden and heavy rains. 相似文献
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Packets of freshly harvested liveSpartina alterniflora were placed on the marsh surface, in a tidal ditch, in a pool contacting sides and bottom, and in the center-bottom of the same pool in September 1972. Rates of loss were the same for all four sites through day 242. After that packets on the marsh surface decomposed slower. A second experiment was begun in July only at the marsh surface and pool side sites. These lost dry weight much more rapidly than packets started in September. Populations of bacteria, fungi, diatoms, flagellates, ciliates and nematodes within the packets peaked within 60 days then decreased proportionately with the loss of dry weight in packets through day 242. After this, bacterial numbers decreased more rapidly presumably in response to a qualitative change in the packet material. Populations of flagellates and ciliates also declined rapidly after day 300. This decline occurred in new packets at around this date as well. In a limited set of samples 12 taxa were analyzed for date or detritus-age dependent occurrence. Of these, eight were data dependent, two were dependent on packet age, and two could not be determined from the data. 相似文献
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The Cretaceous aquifers underlying the central part of the North Carolina Coastal Plain are used extensively as the preferred
source of water for municipalities, industries, and agriculture. Regional decline in head in the middle parts of the system
(the Upper Cape Fear and Black Creek aquifers) began in the late 1950s to early 1960s. The trends in head during the 1960s,
together with data on land subsidence, were analyzed to demonstrate the value of using early data, in conjunction with conceptual
models, before collecting additional data. The sources of withdrawals from the Cretaceous aquifers identified in the conceptual
model are: (1) movement of water (recharge) across confining beds, (2) reduction in natural discharge, (3) release of water
from aquifer storage, (4) drainage of water from fine-grained lenses in aquifers and confining beds, and (5) release of water
resulting from advance of the salt-water front. Estimates of the amounts derived from each of these sources resulted in a
reduction of the estimated safe yield of the Cretaceous aquifers in the 2,486-mi2 (6,439-km2) area of the central Coastal Plain from 75 mgd (million gallons per day) (284,000 m3/day) to less than 5 mgd (19,000 m3/day).
Electronic Publication 相似文献
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《Applied Geochemistry》1999,14(2):197-221
Lead–lead isotope data from whole rock samples are used to investigate the recent (last few million years) mobility of U and Th. The method is based on the comparison of the calculated present day U and Th concentrations required to yield the Pb isotope composition in the samples with the actual present day concentrations of U and Th obtained by direct measurement. The geological formations studied include the Neoproterozoic carbonate sediments of the Bambuı́ Group, Archean/Paleoproterozoic granite–greenstone terrain of the Contendas–Mirante Complex and a Proterozoic ortho-gneisses hosting U deposit in Lagoa Real. All these formations are in the São Francisco Craton, Brazil. The data show high U mobility in the carbonate sediments and in the deformed ortho-gneisses set in a ductile shear zone. Infiltration of groundwater through fault zones seems to have facilitated the U mobility. The Pb isotope approach is a useful technique complementing U-series disequilibrium studies and may be included for site characterization studies for radioactive waste disposal. 相似文献
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2006年春季我国东部海域气溶胶光学厚度与沙尘天气 总被引：1，自引：0，他引：1
结合船基的太阳光度计观测资料和空基卫星遥感的MODIS气溶胶光学厚度资料,研究了我国东部海域气溶胶光学厚度与沙尘天气的关系。通过对不同天气条件下500 nm气溶胶光学厚度的分析,得出晴天(背景天气)、有云和浮尘以及只有浮尘时的平均值分别约为0.2、0.6和1.3以上;将MODIS的气溶胶光学厚度与船基观测资料进行对比之后发现,两者随时间的变化趋势非常一致,但前者在数值上明显偏高;利用订正后的MODIS资料,分析了2006年春季我国东部海域气溶胶光学厚度的时空分布特征,并与我国北方发生的沙尘天气进行了对比,发现两者之间关系密切。 相似文献
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扬子克拉通古大陆边缘Mo同位素特征及对有机埋藏量的指示意义 总被引：5，自引：0，他引：5
通过对扬子克拉通古大陆边缘不同时期沉积岩的Mo同位素进行测定,结合Mo微量元素组成,对古大陆边缘Mo的自生作用规律进行了研究,并根据Mo丰度对原始有机碳堆积速率进行了计算.结果表明,其原始有机碳堆积速率在0.17～0.67mmol/m2/day之间.利用已建立的现代大陆边缘δ98Mo与有机碳埋藏速率模型,对该区不同时期沉积岩的有机碳埋藏速率进行恢复.结果表明,扬子克拉通显生宙不同时期沉积岩的有机碳埋藏速率有较大的变化范围(0.43～2.87mmol/m2/day),并与原始有机碳堆积速率具有明显的相关性,因此,δ98Mo有可能成为评价有效烃源岩的潜在指标. 相似文献
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Ramesh Sivanpillai X. Ben Wu R. Srinivasan Charles T. Smith Michael G. Messina 《GeoJournal》2008,71(4):211-220
Comparing satellite data derived map products are affected by differences in data characteristics, image acquisition dates,
processing techniques, and classification schemes used for assigning pixels to a thematic class. By comparing two forest maps
generated from Landsat Enhanced Thematic Mapper Plus (ETM+) and Advanced Very High Resolution Radiometer (AVHRR) images acquired
on the same day, and processed using identical classification scheme and methods these differences were minimized. The ETM+
derived map had higher classification accuracy values and more precise area estimates than the AVHRR derived map. In the ETM+
derived map, 87 of the 599 verification data were misclassified, whereas in the AVHRR derived map, 155 of the 469 verification
data were misclassified. Detailed error analyses by land cover class revealed that a land use based definition of forest accounted
for 74% (64 out of 87) and 57% (89 out of 155) of the classification errors in ETM+ and AVHRR derived maps, respectively. 相似文献