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531.
长白山火山最新监测信息 总被引:7,自引:1,他引:6
长白山火山最新监测结果显示,自2010年5月份开始,聚龙温泉2个泉点水温同步上升了3℃;2010年长白山北坡垂直位移量打破了火山锥体每年升高4mm左右的规律:与2009年相比,火山锥体的位移在垂向上发生逆转,海拔最高的水准点在1年内突降12.72mm.本文针对上述2个最新的火山监测信息进行了报道,并对造成这种变化的可能原因进行了讨论.火山活动进入活跃时段的标志是大量火山地震、震群的发生,以及幔源岩浆气体He含量的大幅度上升.然而,现阶段长白山火山区并未出现这2种现象.因此,本文讨论的2个异常还不足以作为长白山火山已经进入新的活跃时段的证据,准确的预测应该密切关注火山地震和幔源气体含量的变化.最后通过N2-He-CO2三角图解初步研究了天池火山气体来源,结果显示:2002~2005年火山出现“初始扰动”,深部气体He含量升高,三角图解中气体向He角运移;2005年后火山转入平静状态,气体组份又开始向N2角运移.He浓度的变化特征反应了岩浆房内岩浆成分的变化过程. 相似文献
532.
Settlement is one of the most important deformation characteristics of a high concrete-face rockfill dam (CFRD) and is regarded as a key indicator of dam safety. The time-dependent settlement behavior of the Shuibuya CFRD is studied on the basis of in situ settlement-monitoring records and displacement back-analysis. The goal of this work is to characterize actual deformation of the dam and to verify the back-analysis method used in this paper. The settlement-monitoring records were from seven control stations at the crest and 38 monitoring points inside the body of the dam and covered the construction period, the initial filling of the reservoir and 2 years of operation. A displacement back-analysis for parameters is performed by hybrid generic algorithms (HGAs) and finite element method (FEM). Comparative studies of monitoring data and back-analysis show good agreement between measured settlements and computed settlements. Furthermore, the deformation in the next 3 years is predicted on the basis of back-analysis. Overall, it is demonstrated that the deformation of the Shuibuya CFRD is basically stable and that the technique used to control the dam deformation is successful. 相似文献
533.
随着金属工业和科技的迅猛发展,尾矿库安全生产和环境安全等过程中暴露出的问题日益显现,而我省尾矿库自动监测方面起步较晚。本文依据《尾矿库安全监测技术规范》的相关要求,针对在建尾矿库溃坝原因、监测指标、安全监测与预警系统体系结构和各监测项目实施方案进行比较和探索。进一步说明尾矿库在线监测系统的重要意义。 相似文献
534.
本文在研究我国西部各垂直形变监测区形变特征及其演变的基础上,提出了垂直形变趋势面的概念。据此对我国西部七十年代以来垂直形变进行了阶段划分,并讨论了其与构造应力场变化及地震大形势的关系。进而结合青藏块体近年地震群体特征,对我国西部近期震情进行了分析。 相似文献
535.
Ionospheric variation may be considered as a stationary time series under quiet conditions. However, the disturbance of a
stationary random process from stationarity results in the bias of corresponding samples from the stationary observations,
and in the change of statistical model parameters of the process. From a general mathematical aspect, a new method is presented
for monitoring ionospheric variations, based on the characteristic of time-series observation of GPS, and an investigation
of the statistical properties of the estimated auto-covariance of the random ionospheric delay when changing the number of
samples in the time series is carried out. A preliminary scheme for monitoring ionospheric delays is proposed.
Received: 18 August 2000 / Accepted: 12 April 2001 相似文献
536.
Since the commencement of mining at the Himmetoğlu coal mine, northwest Turkey, serious stability problems have led to interruptions
in mining and some environmental effects. A geotechnical investigation was initiated in 1997 and the significant factors that
influence the stability have been defined. This paper outlines the results of the field and laboratory studies associated
with the causes and mechanism of the slope instabilities and their environmental impacts. The possible remedial measures to
improve the stability and to minimize the environmental problems are also described. Back-analyses and data from long-term
monitoring indicate that the failures occur along two or three planar surfaces by combination of faults and localized strata
steepening adjacent to the faults. The stability is sensitive to changes in length of the lower part of the basal sliding
surface and shear strength of the bedding surfaces in the overburden. Suitable remedial measures include slope flattening
(i.e. staged bench stripping), proper drainage and spreading of a rock blanket on the pit floor to increase spoil pile stability.
Received: 18 April 2000 · Accepted: 15 August 2000 相似文献
537.
本文研究了FY-1BVHRSR的三个可见光通道和一个近红外通道监测1991年夏天中国江淮地区洪水的能力。分析该区域不同水体的各个通道的光谱状况表明,VHRSR第二通道区别水、陆(植被)边界十分显著,VHRSR第一通道有感应洪水泥沙含量信息的能力,VHRSR的第三、四通道(海洋通道)则可以获得水深信息。文中针对FY-1B的波段的特点设计了几种信息增强方法,从而有效地识别出水陆边界,计算了洪水深度及洪水浑浊度的相对等级,精确地统计出洪水的面积。结果表明FY-1B在洪水监测中大有潜力。 相似文献
538.
本文简要介绍了地电自动测量系统C-ATS中所采取的技术措施,系统结构和它在地震前兆观测中广泛的应用前景。 相似文献
539.
This paper describes the simulation and real data analysis results from the recently launched SAR satellites, ALOS-2, Sentinel-1 and Radarsat-2 for the purpose of monitoring subsidence induced by longwall mining activity using satellite synthetic aperture radar interferometry (InSAR). Because of the enhancement of orbit control (pairs with shorter perpendicular baseline) from the new satellite SAR systems, the mine subsidence detection is now mainly constrained by the phase discontinuities due to large deformation and temporal decorrelation noise.This paper investigates the performance of the three satellite missions with different imaging modes for mapping longwall mine subsidence. The results show that the three satellites perform better than their predecessors. The simulation results show that the Sentinel-1A/B constellation is capable of mapping rapid mine subsidence, especially the Sentinel-1A/B constellation with stripmap (SM) mode. Unfortunately, the Sentinel-1A/B SM data are not available in most cases and hence real data analysis cannot be conducted in this study. Despite the Sentinel-1A/B SM data, the simulation and real data analysis suggest that ALOS-2 is best suited for mapping mine subsidence amongst the three missions. Although not investigated in this study, the X-band satellites TerraSAR-X and COSMO-SkyMed with short temporal baseline and high spatial resolution can be comparable with the performance of the Radarsat-2 and Sentinel-1 C-band data over the dry surface with sparse vegetation.The potential of the recently launched satellites (e.g. ALOS-2 and Sentinel-1A/B) for mapping longwall mine subsidence is expected to be better than the results of this study, if the data acquired from the ideal acquisition modes are available. 相似文献
540.