汶川8级地震后对地震数据远程传输方式的思考     

康宏  王余伟  吴彤 《地震地磁观测与研究》2010,31(4):32-38

2008年5月12日汶川8.0级特大地震,是继1976年唐山大地震后的又一人间悲剧。灾难过后,痛定思痛,如何保证在非常时期将地震数据可靠地传输回台网管理中心,为研究人员提供完整的数据波形,是地震观测技术人员在这次地震后应该慎重思考的问题之一。本文收集比较了中国地震部门常用的4种地震数据传输方式在8.0级特大地震中的表现,供同行参考。  相似文献   

Geochemistry of organic carbon and nitrogen in surface sediments of coastal Bohai Bay inferred from their ratios and stable isotopic signatures   总被引：6，自引：0，他引：6  

Gao X  Yang Y  Wang C 《Marine pollution bulletin》2012,64(6):1148-1155

Total organic carbon (TOC), total nitrogen (TN) and their δ(13)C and δ(15)N values were determined for 42 surface sediments from coastal Bohai Bay in order to determine the concentration and identify the source of organic matter. The sampling sites covered both the marine region of coastal Bohai Bay and the major rivers it connects with. More abundant TOC and TN in sediments from rivers than from the marine region reflect the situation that most of the terrestrial organic matter is deposited before it meets the sea. The spatial variation in δ(13)C and δ(15)N signatures implies that the input of organic matter from anthropogenic activities has a more significant influence on its distribution than that from natural processes. Taking the area as a whole, surface sediments in the marine region of coastal Bohai Bay are dominated by marine derived organic carbon, which on average accounts for 62±11% of TOC.  相似文献   

卫星地震台站的电源设计与应用     

王翠芳  王余伟 《地震地磁观测与研究》2014,(3):215-219

从设备功耗、气象条件、太阳能板、蓄电池规格等方面设计卫星传输方式所需电源方案,并用于实际传输。由3个月考核运行期的运行率表明：卫星传输方式的电源设计是成功的、合理的,保证卫星地震台站稳定可靠的运行。  相似文献   

阶跃响应测定地震计周期与阻尼的精度研究     

邵玉平  王翠芳  王余伟  张勇 《地震地磁观测与研究》2014,(1):213-218

对阶跃响应波形的时域测定与频域测定两种方法进行对比计算,结果表明,频域测定法的计算精度提高约1个数量级。研究地震计周期与阻尼参数的影响因素,应优先选用频域测定法。  相似文献   

临武碉楼建筑特征及功能探析     

何峰  李雨薇  陈征 《热带地理》2016,36(2):208-215

临武碉楼是湘南地区一类独特的历史文化遗存,历史悠久,在临武乡村分布极为广泛,但目前遗存不足10座。这些建筑通常选址于村口下方数十至数百米之处的古道旁或水塘间,被当地人称为“水口”“下守”。临武碉楼外形封闭坚固,四面墙体从上而下布满了排列有序的长方形射击孔,军事防御功能明显。此外,临武人还赋予碉楼宗教神殿、书院私塾、亭台楼阁和风水守护等功能。临武碉楼为研究临武古代军事防御体系、社会文化、建筑艺术、民俗风情等提供了珍贵的实物史料,具有极高的历史、科学和艺术价值。  相似文献   

抽水蓄能电站综合防雷设计探讨     

马刚  郑绍勋  田金华  张玉伟 《气象与环境科学》2008,31(3):90-93

雷电是严重威胁电站安全的最大自然灾害,通过研究南阳回龙抽水蓄能电站雷电发生规律和发展过程,并对电站多次雷击进行分析,判定发电设备雷击的原因,经理论计算,提出发电设施综合防雷设计方案,以达到电站管理控制系统和设备安全防雷的目的.  相似文献   

Crustal Structure and Extension from Slope to Deepsea Basin in the Northern South China Sea     

Hu Dengke  Zhou Di  Wu Xiangjie  He Min  Pang Xiong  Wang Yuwei 《中国地质大学学报(英文版)》2009,20(1)

The newly acquired long-cable multi-channel seismic (MCS) lines were used to study the crustal structure and extension in an NW-SE elongated 150 km by 260 Van strip from the slope to the deepsea basin in the northern South China Sea (SCS).These profdes are of good penetration that Moho is recognizable in ～70% length of the lines.Seismostrattgraphic interpretation and time-depth conversion were conducted.A power function D = atb+ c was used in the time-depth conversion,which avoided the under-or over-estimation of the depths of deep-seated interfaces by cubic or quadratic polynomial functions.Contour maps of basement depth,Moho depth,crustal thickness,and crustal stretching factor were obtained for the study area.In the dip direction,the Moho depth decreases stepwisely from 28 km in the outer shelf southwards to 19,15,and 12 km in the deepsea basin,with ramps at the shelf break,lower slope,and the continent ocean boundary (COB),respectively.Accordingly,the crustal thickness decreased southwards from 3,and 7 km spectively.Under the center of the Balynn (白云) sag,the crust thins significantly to ＜ 7 kin.The crustal stretching factor βc was calculated by assuming the original crust thickness of 30 km.In the centers of the Baiyun sag,βc exceeds 5.Tertiary and Quaternary volcanic activities show a general trend of intensifying towards the COB.An important finding of this study is the along-strike variation of the crustal structure.A Moho rise extends from the COB NW-ward until the shelf break,about 170 km long and 50-100 km wide,with Moho depth ＜ 20 kin.This is called the Balyun Moho Nose,which is bounded to the east,west,and north by belts of high Moho gradients indicative of crustal or even lithospheric faults.The doming of Moho in the nose area might he the cause of the W-E segmentation of the crustal and geological structures along the slope of the northern South China Sea,and the cause of the strong crustal stretching in the Baiyun and Liwan (荔湾) sags.  相似文献   

Lead isotopic composition and genesis of Phanerozoic metal deposits in China     

Yuwei Chen  Cunxiao Mao  Bingquan Zhu 《中国地球化学学报》1982,1(2):137-158

Lead isotopic compositions of more than 130 galena specimens from Phanerozoic metal deposits in China have been analyzed with a standard deviation of less than 0.5%. The ranges of isotopic composition are from 17.8 to 19.3 for Pb²⁰⁶/Pb²⁰⁴, 15.2 to 16.0 for Pb²⁰⁷/Pb²⁰⁴ and 37 to 40.8 for Pb²⁰⁸/Pb²⁰⁴. These values overlap those of MORB, pelagic chemical sediments and intra-oceanic arcs of western Pacific in plots of Pb²⁰⁷/Pb²⁰⁴ vs. Pb²⁰⁶/Pb²⁰⁴ and Pb²⁰⁸/Pb²⁰⁴ vs. Pb²⁰⁶/Pb²⁰⁴. This indicates that mixing between mantle and crustal materials due to partial melting of the Pacific subduction slab is the principal mechanism for ore genesis. On the basis of global Precambrian conformable leads, together with that of Guanmenshan, Pengjiapu and Baiyun deposits in China, it is suggested that mantle lead was developed in a single stage with a (U²³⁸/Pb²⁰⁴) value of 7.8. If the ages of igneous rocks associated with these deposits are adopted as formation ages, the mean Th/U of the second stage of crust-mantle evolution can be calculated with a lead mixing model. The meanμ value of China continent is 9.98±0.78, which is in agreement with that of global conformable leads, 9.81±0.58. The mean Th/U ratio of 4.27 is distinctly larger than the global value (3.81), indicating that the China continent is rich in Th. Simultaneously, mean formation ages have also been obtained of the continental crusts in various regions, ranging from 3,000 to 3,800 m.y. and from 2,500 to 2,700 m.y., which are comparable with the age distribution of global Archaean cratons.  相似文献   

Rare earth elements in sediments of the China continental shelf     

Zhao Yiyang  Wang Jintu  Qin Zhaoyang  Chen Yuwei  Wang Xianjue  Wu Mingqing 《中国海洋湖沼学报》1989,7(1):70-78

Determination of the concentrations of, 15 rare earth elements (REE) in China continental shelf sediments by X-ray fluorescent spectral analysis of selected representative sediment samples showed that REE concentration in the sediments is 156 ppm, similar to that in China loess and Fujian granite, but different from that in Pacific sediments. The shelf REE have the characteristic distribution pattern of typical continental crust REE and evidently philo-continental property. The above findings suggest that weathered materials transported from the China continent are the main source of the REE in China continental shelf sediments. Experiments show that REE exist mainly in the crystal lattices of clay minerals (<2μ) as isomorphs and that REE have close relation with most elements (Al, Ti, K, Rb, Fe, etc.) related with clay minerals, but have negative correlation with the biophile elements Ca and Sr. Contribution No. 1520 from the Institute of Oceanology, Academia Sinica.  相似文献   

正负地震差值Se值在华东地震中期预报的应用   总被引：1，自引：0，他引：1  

陈宇卫  张军  庆梅  闫素萍 《地震地磁观测与研究》2003,24(1):49-54

使用反映应力调制作用的正负地震差值Se值对华东地区进行空间扫描。结果表明，中强地震前，华东陆地5级地震前1－3a会出现正负地震差值Se值异常，未来地震会发生在异常单元150km区域内或周边地区，而霍山地区出现Se值异常后，能较好的对应华东海域和陆地5级以上地震。因此，该方法在华东地区具有较好的预报效果。  相似文献