高精度温度计在同层水温平行观测中的互相干扰现象     

邱永平 《中国地震》2016,32(1):151-156

在2015年4月24日一次意外供电故障中,发现宁波地震台高精度温度计在井水温度同层平行观测中有明显的互相干扰现象。认为目前水温观测到的是水井内实际温度与传感器工作时的"升温值"之和,而"升温值"是动态值,其取决于每套仪器的系统特性,一般可能会在0.01℃以上;相互影响可能在0.005℃以上,如果是捆绑式平行观测可能会更高。所以水温测值的波动范围为10~(-4)℃的观测井中,这种干扰不可忽视,并可能影响前兆异常的提取。因此,在水温波动比较小的观测井(泉)中,不主张做同层平行对比观测。最好在一个传感器内安装2套探测温度装置,既免互相干扰,又可相互验证。  相似文献   

Strong ground motion simulation for the 2013 Lushan M_W6.6 earthquake,Sichuan, China,based on the inverted and synthetic slip models     

Wenhao Shen  Qiu Zhong  Baoping Shi 《地震学报(英文版)》2014,(4):377-389

It is well known that quantitative estimation of slip distributions on fault plane is one of the most important issues for earthquake source inversion related to the fault rupture process. The characteristics of slip distribution on the main fault play a fundamental role to control strong ground motion pattern. A large amount of works have also suggested that variable slip models inverted from longer period ground motion recordings are relevant for the prediction of higher frequency ground motions. Zhang et al. （Chin J Geophys 56：1412-1417, 2013） and Wang et al. （Chin J Geophys 56：1408-1411,2013） published their source inversions for the fault rupturing process soon after the April 20, 2013 Lushan earthquake in Sichuan, China. In this study, first, we synthesize two forward source slip models： the value of maximum slip, fault dimension, size, and dimension of major asperities, and comer wave number obtained from Wang＇s model is adopted to constrain the gen- eration of k-2 model and crack model. Next, both inverted and synthetic slip models are employed to simulate the ground motions for the Lushan earthquake based on the stochastic finite-fault method. In addition, for a comparison purpose, a stochastic slip model and another k-2 model （k 2 model II） with 2 times value of comer wave number of the original k-2 model （k 2 model I） are also employed for simulation for Lushan event. The simulated results characterized by Modified Mer- calli Intensity （MMI） show that the source slip models based on the inverted and synthetic slip distributions could capture many basic features associated with the ground motion patterns. Moreover, the simulated MMI distributions reflect the rupture directivity effect and the influence of the shallow velocity structure well. On the other hand, the simulated MMI bystochastic slip model and k 2 model II is apparently higher than observed intensity. By contrast, our simulation results show that the higher frequency ground motion is sensitive to the degree of sli  相似文献   

几种甘草（Glycyrrhiza）光合特性、形态特征及生物量比较   总被引：1，自引：0，他引：1  

叶菊  蔺海明  邱黛玉  张汉平  王升元  闫立本  赵贵亮 《中国沙漠》2014,34(2):456-463

采用TPS-2型光合测定仪对乌拉尔甘草（Glycyrrhiza uralensis）、胀果甘草（G.inflata）、刺果甘草（G.pallidiflora）、光果甘草（G.glabra）和黄甘草（G.eurycarpa）栽培植株上部叶片光合日变化特征进行研究,对光合色素、形态和生物量进行测定和分析,并比较上述指标的种间差异,为甘草栽培技术和综合利用模式提供科学依据。结果表明：（1）各种的叶片净光合速率、蒸腾速率、水分利用率和气孔导度日变化均呈“双峰”型,峰值分别出现于12：00和16：00,14：00存在明显的光合“午休”现象;叶片细胞间隙CO₂浓度日变化均呈“W”型,峰值分别出现于08：00、14：00和18：00,低谷出现于12：00和16：00;叶片温度日变化均呈“倒V”型,峰值出现于14：00,低值出现于08：00和18：00;且各种上述指标存在不同程度的差异性。（2）各种的叶片叶绿素a、叶绿素b、类胡萝卜素含量及叶绿素总量和叶绿素a含量/叶绿素b含量大小各不相同,其中叶绿素a含量存在种间显著差异。（3）各种的主茎分枝数、叶片数、主茎高、主根长、地上部分干重、地下部分干重及总生物量存在一定的差异性。（4）净光合速率日均值与气孔导度、蒸腾速率、水分利用效率、叶面温度日均值和叶绿素a含量正相关,相关系数分别为0.984、0.977、0.927、0.909和0.933,与胞间CO₂浓度负相关,相关系数为-0.972。乌拉尔甘草具有较高的光合性能和经济产量,适于在该区大规模推广栽培;胀果甘草、光果甘草和刺果甘草总生物量较大,除地下部分药用外,应加强对其地上部分的开发利用;黄甘草光合性能、经济产量和总生物量均显著低于其他种,但地上部分鲜嫩,建议对其加强畜牧业方面的开发利用。  相似文献   

探讨农村雷电灾害的成因及防雷减灾对策   总被引：8，自引：0，他引：8  

朱明  丘志彪  蔡木民  刘开道 《气象研究与应用》2012,33(1):90-92

总结了农村雷电灾害事故发生的现状;分析阐述了农民防雷科学知识贫乏、观念淡薄,防雷设施滞后,防雷管理不到位及雷电预警信息发布不畅等因素是导致农村雷电灾害事故频发的根本原因;针对上述存在的问题,提出了做好农村防雷减灾工作的四点对策是加强防雷知识宣传,创新管理模式,加快雷电预警信息发布和强化责任落实,对加强农村防雷减灾工作具有很好的指导意义。  相似文献   

The Evolution of a Meso-β-Scale Convective Vortex in the Dabie Mountain Area   总被引：1，自引：0，他引：1       下载免费PDF全文

XU Wenhui  NI Yunqi  WANG Xiaokang  QIU Xuexing 《Acta Meteorologica Sinica》2012,26(5):597-613

The evolution of a mesoscale convective system (MCS) that caused strong precipitation in the northern area of Dabie Mountain during 21-22 June 2008 is analyzed, along with the evolution of the associated meso-β-scale convective vortex (MCV). The mesoscale reanalysis data generated by the Local Analysis and Prediction System (LAPS) at a 3-km horizontal resolution and a 1-h time resolution during the South China Heavy Rainfall Experiment (SCHeREX) were utilized. The results show that two processes played key roles in the enhancement of convective instability. First, the mesoscale low-level jet strengthened and shifted eastward, leading to the convergence of warm-wet airflow and increasing convective instability at middle and low levels. Second, the warm-wet airflow interacted with the cold airflow from the north, causing increased vertical vorticity in the vicinity of steeply sloping moist isentropic surfaces. The combined action of these two processes caused the MCS to shift progressively eastward. Condensation associated with the MCS released latent heat and formed a layer of large diabatic heating in the middle troposphere, increasing the potential vorticity below this layer. This increase in potential vorticity created favorable conditions for the development of a low-level vortex circulation. The vertical motion associated with this low-level vortex further promoted the development of convection, creating a positive feedback between the deep convection and the low-level vortex circulation. This feedback mechanism not only promoted the maturation of the MCS, but also played the primary role in the evolution of the MCV. The MCV formed and developed due to the enhancement of the positive feedback that accompanied the coming together of the center of the vortex and the center of the convection. The positive feedback peaked and the MCV matured when these two centers converged. The positive feedback weakened and the MCV began to decay as the two centers separated and diverged.  相似文献   

南海西北部陆坡H1事件的磁学记录     

李明坤  欧阳婷萍  朱照宇  田成静  彭莎莎  邱燕  彭学超  钟和贤  陈泓君 《第四纪研究》2019,39(4):927-937

Heinrich 1(H1)事件,是末次冰消期内一个重要的千年尺度的古气候事件.南海不同海域沉积物磁学性质对H1事件的响应存在差异,因而磁学参数的多解性应予以关注.本文选取南海西北部陆坡具有良好年龄框架的PC338岩芯顶部370 cm段(底部年龄20. 5 ka B. P.),进行详细的磁学性质分析,并利用IRM获得曲线组分分离方法和高场磁化率值等参数,试图为区域气候变化的沉积物磁学响应给出合理解释.结果表明,在H1事件发生时,碎屑成因的磁铁矿(IRM (C2+C3))和顺磁性组分(xp)明显降低,这反映了源区化学风化的减弱,指示南海北部冷干的气候条件;另外, H1事件发生时,南海西北部陆坡的赤铁矿含量较高,这与海平面降低造成的红河源区的赤铁矿输入增多和暴露的大陆架处于氧化条件有关. H1事件时期,东亚季风区呈现末次冰消期以来最干旱的气候特征,主要受控于大西洋经向翻转环流的减弱迫使热带辐合带南移和热带太平洋类La Nina的气候条件这两个因素.  相似文献   

Application and Verification of Joint Probability Method in Potential Forecast for Severe Convective Weather in Anhui Province     

Yuejia Zhu  Rui Xing  Mingjia Zhu  Dongyong Wang  Xuexing Qiu 《地球科学进展》2019,34(7):731-746

In consideration of large uncertainties in severe convective weather forecast, ensemble forecasting is a dynamic method developed to quantitatively estimate forecast uncertainty. Based on ensemble output, joint probability is a post-processing method to delineate key areas where weather event may actually occur by taking account of the uncertainty of several important physical parameters. An investigation of the environments of little rainfall convection and strong rainfall convection from April to September (warm season) during 2009-2015 was presented using daily disastrous weather data, precipitation data of 80 stations in Anhui province and NCEP Final Analysis (FNL) data. Through ingredients-based forecasting methodology and statistical analysis,four convective parameters characterizing two types of convection were obtained, respectively, which were used to establish joint probability forecasting together with their corresponding thresholds. Using the ECMWF ensemble forecast and observations from April to September during 2016-2017, systematic verification mainly based on ROC and case study of different weather processes were conducted. The results demonstrate that joint probability method is capable of discriminating little rainfall convection and non-convection with comparable performance for different lead times, which is more favorable to identifying the occurrence of strong rainfall convection. The joint probability of little rainfall convection is a good indication for the occurrence of regional or local convection, but may produce some false alarms. The joint probability of strong rainfall convection is good at indicating regional concentrated short-term heavy precipitation as well as local heavy rainfall. There are also individual missing reports in this method, and in practice, 10% can be roughly used as joint probability threshold to achieve relative high TS score. Overall, ensemble-based joint probability method can provide practical short-term probabilistic guidance for severe convective weather.  相似文献   

China's Urbanization and Its Ecological Environment Challenges in the 21st Century   总被引：1，自引：1，他引：0  

Guoyu Qiu  Xiaonan Zhang 《地球科学进展》2019,34(6):640-649

Urbanization is a worldwide historical process. Although China's urbanization started late, it is fast, large in scale, high in resource and energy consumption, and leads to a series of water and thermal environment problems. This paper systematically sorted out the ecological environment challenges faced by Chinese cities under the dual pressures of global climate change and urbanization, such as water shortages and water pollution, increasingly serious urban heat island issues and ecological hydrological disasters. It proposed to solve the problem of urban ecological environment with the theory and means of urban ecohydrology, improve the quality of urbanization in China, and realize livable cities.  相似文献   

中国东部中、新生代含油气盆地火成岩油气藏成藏机制   总被引：17，自引：1，他引：16  

吴昌志顾连兴  任作伟陈振岩  赵明邱津 《地质学报》2005,79(4):522-530

中国东部中、新生代盆地油气资源丰富,其地层中广泛发育着以玄武质及粗面质为主的火成岩。这些火成岩既可为油气提供储集空间也可作为油气藏的盖层,形成了一定量与火山岩及潜火山岩相关的油气藏。与火山岩有关的油气藏主要有火山岩储层型、火山岩盖层型和风化壳型,而与潜火山岩有关的油气藏主要有拱张裂缝型、隐爆角砾岩型、原生裂缝型、蚀变破碎型和侧向隔挡型。本文评述了这些火成岩型油气藏的成藏机制,提出了中国东部中、新生代含油气盆地中的火成岩油气藏综合成藏模型,以期这类油气藏在今后的油气勘探工作中得到充分重视。  相似文献   

利用磷灰石裂变径迹研究塔里木盆地中部地区的热历史   总被引：12，自引：1，他引：11  

李慧莉  邱楠生  金之钧 《地质科学》2005,40(1):129-132

利用磷灰石裂变径迹反演计算了塔里木中部地区3口井志留纪以来的热历史。研究认为,塔中地区志留纪以来的大地热流变化不大,为56～62mW/m²。志留纪、泥盆纪大地热流较低,约为58mW/m²;石炭纪大地热流略有增高,二叠纪时大地热流可能达到62mW/m²;中生代期间,大地热流逐渐降低,中生代末约为57mW/m²;新生代期间,大地热流略有增高,现今大地热流约为60mW/m²。塔中地区的热历史与其构造演化史密切相关。  相似文献