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The Improvement of Earthquake Real-Time Monitoring System of Chinese National Digital Seismic Network 总被引：1，自引：0，他引：1
The earthquake real-time monitoring system of the Chinese National Digital Seismic Network has been in operation since "the Ninth Five-year Plan" period, and the stability of the system has been well tested. In recent years, with the continuous improvement of monitoring technology and increase of public demands, the original real-time monitoring system needs to be upgraded and improved in terms of timeliness, stability, accuracy and ease of operation. Therefore, by accessing a total of more than 1,000 seismic stations, reducing the seismic trigger threshold of the monitoring system, eliminating the false trigger stations and optimizing the seismic waveform display interface, the current earthquake monitoring demands can be satisfied on the basis of ensuring the stable operation of the system. 相似文献
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Hairong Lai Christopher T. Russell Hanying Wei Tielong Zhang 《Meteoritics & planetary science》2014,49(1):28-35
Asteroid 2201 Oljato passed through perihelion inside the orbit of Venus near the time of its conjunction with Venus in 1980, 1983, and 1986. During those three years, many interplanetary field enhancements (IFEs) were observed by the Pioneer Venus Orbiter (PVO) in the longitude sector where the orbit of Oljato lies inside Venus' orbit. We attribute IFEs to clouds of fine‐scale, possibly highly charged dust picked up by the solar wind after an interplanetary collision between objects in the diameter range of 10–1000 m. We interpret the increase rate in IFEs at PVO in these years as due to material in Oljato's orbit colliding with material in, or near to, Venus' orbital plane and producing a dust‐anchored structure in the interplanetary magnetic field. In March 2012, almost 30 yr later, with Venus Express (VEX) now in orbit, the Oljato‐Venus geometry is similar to the one in 1980. Here, we compare IFEs detected by VEX and PVO using the same IFE identification criteria. We find an evolution with time of the IFE rate. In contrast to the results in the 1980s, the recent VEX observations reveal that at solar longitudes in which the Oljato orbit is inside that of Venus, the IFE rate is reduced to the level even below the rate seen at solar longitudes where Oljato's orbit is outside that of Venus. This observation implies that Oljato not only lost its co‐orbiting material but also disrupted the “target material,” with which the co‐orbiting material was colliding, near Venus. 相似文献
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Zhenying Liu Zhaohui Jin Yawei Li Tielong Li Jiujun Gu Si Gao 《Environmental Geology》2007,52(5):997-1005
Sediment phosphorus (P) fractions and profile distribution at submerged macrophyte growth zone, emergent macrophyte growth
zone and open-water zone were studied in Wuliangsuhai Lake, China, as well as the correlations among water content, grain
size, and organic matter and P fractions. Among the three surveyed zones, the highest concentrations of most P forms occurred
in the surface sediment and the lowest between a depth of 12 and 22 cm, except HCl-P and NaOH-P. Sediment phosphorus was mainly
associated to inorganic forms (>50%) in three surveyed areas, and the highest value of inorganic phosphorus (IP) in the surface
sediment was obtained from submerged macrophyte growth zone. Submerged and emergent macrophytes increased the IP content by
107 and 44 μg/g, respectively, in the surface sediment compared with open-water zone. Vertical profiles of IP in the three
surveyed zones showed that the concentrations decreased from surface to 12 cm depth and then increased. There was a similar
trend in the sediment profiles of organic phosphorus (OP) and total phosphorus (TP), but the highest concentration of OP and
TP in surface sediment was obtained from the emergent macrophyte growth zone. Compared with open-water zone, the emergent
macrophyte increased TP content in surface sediment by 1.73 times to 1,320 μg/g, while submerged macrophyte enhanced TP content
in the surface sediment by 1.13 times to 865 μg/g. It was observed that in macrophyte growth zones, a strong linear correlation
existed between organic matter and OP (r > 0.98), and the maximum concentrations of OP were present in the areas with maximum concentrations of organic matter. Results
show that, although rooted macrophyte could uptake directly P from sediments, it is responsible for increasing the internal
P loading especially OP by reducing current velocities, attenuating wave energy and generating organic residue in Wuliangsuhai
Lake. 相似文献
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江西省金山金矿有机流体与金矿关系 总被引：13，自引：4，他引：9
对江西省金山金矿流体包裹体研究表明,矿区发育的包裹体有：①气－液两相盐水溶液包裹体,占包裹体总量８０％～８５％;②纯有机烃类包裹体,占包裹体总量１０％～１５％;③含盐类子矿物多相包裹体,占包裹体总量１％左右;④纯ＣＯ２包裹体（含液态ＣＯ２三相包裹体）,占包裹体总量１％以下。流体时空演化表明,成矿前深大断裂引发深部流体上侵,带来了深部的纯ＣＯ２流体和岩浆期后高盐度流体,伴随后期构造活动,大量向下循环的大气水,不仅温度升高,而且在水－岩交换过程中带来地层中的有机质。在对流体包裹体深入研究的基础上,对成矿流体种类、流体的时空演化,特别是有机流体在成矿中的作用等进行了有益的探索 相似文献
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利用河北及邻区地震台网提供的震相观测报告,使用双差定位方法,对2020年7月12日唐山古冶MS 5.1地震序列进行重新定位,并基于部分地震台站记录的波形资料,采用近震全波形方法,反演得到主震震源机制解。精定位结果显示,此次地震序列展布长度约8 km,余震自主震位置向SW扩展,震源深度优势分布范围在10—18 km,发震断层面较陡,倾向SE。震源机制解显示,主震为一次走滑型事件,结合序列展布形态和地震活动背景,SW—NE向近似直立节面为可能发震断层面,与1976年唐山MS 7.8主震断层特征基本一致。综上所述,古冶MS 5.1地震为唐山MS 7.8地震的又一次余震,属唐山老震区正常地震活动。 相似文献
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借鉴美国地质调查局（USGS）开发的Earthworm地震监测系统中自动地震定位模块的思想,将其中binder_ew软件模块功能应用到中国地震台网中心（CENC）开发的国家数字地震台网地震实时监测系统软件Ecums_rt中,运用地震震相关联方法,降低误触发地震台站对地震自动定位的干扰,从而实现软件优化,提升了Ecums_rt系统的地震事件自动定位监测能力。 相似文献