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通过对山西省离石地震台数字化水平摆SSQ-2I与模拟水平摆SQ-70B的观测资料进行对比分析,认为从资料的完整性、稳定性、可靠性以及观测精度方面,数字化水平摆SSQ-2I均优于模拟水平摆SQ-70B。数字化水平摆能实现远距离快速传输、及时准确地发现异常,实现资源共享。 相似文献
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Self-potential (SP) surveys were conducted on 10 island-arc-type volcanoes in Japan. Large-scale SP anomalies that covered entire volcanic edifices and had simple shapes were observed. Neglecting the local fluctuations, we named the SP anomaly that shows voltage gradients anywhere on the flank a long spatial wavelength (LSW) SP anomaly. We first classified these anomalies into three types: 1) no anomaly (SP profile is flat): 2) “W”-shaped profile: and 3) “V”-shaped profile. In some volcanoes, one flank with a flat SP profile and another with half of the W-shaped SP profile coexist. Next, we compared LSW-SP anomalies with various factors that may be related to SP generation and found that the SP profile is approximately flat on the flank where geothermal manifestations exist. This relationship, which is new aspect of the SP data on volcanoes, is important because it can impose a constraint on the model for SP generation and the subsurface structure. Based on the discussion that SP is generated by an electrokinetic mechanism, we propose that resistivity, zeta potential, and hydraulic radius are the possible parameters that control the existence of LSW-SP anomalies. The new relationship between SP and geothermal manifestation are understood in terms of the presence of hydrothermal system. Although the structure of volcanic edifice is probably spatially complicated, the insight into the SP data presented in this study implies that the flanks with flat SP profiles are relatively weak and have high potential for sector collapse. 相似文献
175.
Audray Delcamp Benjamin van Wyk de Vries Mike R. James 《Journal of Volcanology and Geothermal Research》2008
Gravitational volcano spreading is caused by flow of weak substrata due to volcanic loading, and is now a process known to affect many edifices. The process produces extension in the upper edifice, evidenced by gräben and normal faults, and compression at the base, seen in strike–slip faults and thrusts. Where spreading is identified, host volcanoes have a range of fault densities, variable rift and gräben shapes, and different degrees of structural asymmetry. Previous studies have suggested a link between edifice shape and structure and the proportion of brittle to ductile material in the substrata or lower edifice. We study this link using refined sand cone analogue models standing on a brittle–ductile/sand–silicone substrata. Two scenarios have been investigated, the first mainly represents oceanic volcanoes with a ductile layer within the edifice (type I), where there is an outer ductile free surface. The second represents most continental volcanoes that have ductile substrata (type II). We apply the model results to natural examples and develop quantitative relationships between slope, brittle–ductile ratio fault density, spreading rate and structural style. Displacement fields calculated from stereophotogrammetry show significant differences between different slope models. We find that more faults are produced when the cone is initially steeper, or when the brittle substratum is thinner. However, the effect of the brittle layer dominates over that of slope. The strike–slip movements are found to be an essential feature in the spreading mechanism and the gräben are in fact transtensional features. Strike–slip and graben faults make a conjugate flower pattern. The structures produced are well-organised for type II edifices, but they are poorly organised for type I models. Type I models represent good analogues for oceanic volcanoes that are commonly affected by large slumps bounded by an extensional zone and lack of well-formed sector gräben. The well-observed connection between oceanic volcano rifts and large landslide-slumps is confirmed to be a consequence of spreading. 相似文献
176.
1986年3月30日至12月25日为期271天的冬季地震观测中,中国南极长城站地震台共记录到各种震动3000余次,其中大部分为长城湾冰层破裂产生的微震,4次为南设得兰群岛邻近海域中的浅源地震以及5月7日阿留申群岛发生的8.1级地震和4月14日南桑韦奇群岛发生的6.4级地震。冰震与构造地震具有明显的差异。1986年11月16日的地震记录为分析冰震与构造地震的区别提供了很好的例证。冰震具有初动尖锐、频率高和衰减快的特征。根据初动和波型很容易将冰震与构造地震区分开。 相似文献
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在全球能源低碳转型的背景下,白银不仅广泛应用于电子电气、钎焊合金等传统工业领域以及首饰银器和投资领域,更是与光伏、电动汽车和5G技术等绿色清洁能源领域密切相关。本研究采用部门分析法分别预测在既定政策情景(STEPS)、宣布承诺情景(APS)和2050年净零排放情景(NZE)三种情景下光伏、电动汽车领域的白银需求,并使用ARIMA模型分析传统工业领域需求,预测至2035年全球白银需求。研究结果表明,三种情景下, 2035年工业领域对白银的需求量分别为19 360 t、21 621 t和26 894 t。在中情景下(APS情景)低碳领域白银需求量将在2031年超过传统工业领域白银需求量;在高情景下(NZE情景)低碳领域需求量将在2024年超过传统工业领域白银需求量。 相似文献
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中国地震报告数据处理系统 总被引:1,自引:0,他引:1
地震观测报告是一份具有广泛使用价值的地震基础资料。中国地震报告数据处理系统是提高中国地震报告质量的关键一环。其主要水平反映在:数据采集和处理自动化;采用最先进的数值计算方法;采用最先进的激光照排技术;用磁介质进行数据传递。 相似文献