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151.
152.
数字地震仪(或雷达)的文件格式及其转换方法 总被引:3,自引:0,他引:3
详细介绍了SEG新规定的SEG-2标准及其文件结构,这一标准不但适用于数字地震仪,而且也适用于地质雷达等数字化记录设备。同时给出了一个在IBM-PC环境不读取SEG-2数据文件的C语言示范程序,根据这个示范程序,用户可以很方便地将SEG-2数据文件转换成适用于特定应用软件的数据格式。 相似文献
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基于2021年、2022年中国5.0级及以上地震目录,结合应急管理部、有关省(自治区、直辖市)地震局的地震灾害评估报告和相关资料,对中国大陆地震灾害情况、主要地震灾害事件及其特点进行了总结和分析。此外,按省份总结了各省地震灾害事件及地震灾害特点。其中,云南省中强震多、强震少,震区房屋抗震能力较高,人员伤亡较小; 四川省中强震少、强震多,次生灾害较为发育,造成严重人员伤亡; 青海省虽然震级高、破坏性强、致灾范围广,但震区地广人稀,房屋抗震设防等级较高,人员伤亡少。最后,结合历史震害统计数据,分析对比近2年中国大陆地震灾害致灾特点。 相似文献
156.
选取福建地震台网"十五"观测系统2009—2015年记录的748个M_L≥1.0地震事件,采用多台和达法计算福建区域波速比值和泊松比值,并绘制二者空间等值线图,分析其分布特征,讨论波速比值高低与震级大小和震源深度的关系,结果发现,波速比大小与二者关系不大。 相似文献
157.
Multivariate properties of extreme precipitation events in the Pearl River basin,China: Magnitude,frequency, timing,and related causes 总被引:1,自引:0,他引:1
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Daily precipitation/temperature data collected at 74 weather stations across the Pearl River basin of China (PRBC), for the years 1952–2013, were used to analyse extreme precipitation (EP) processes at annual and seasonal scales in terms of precipitation magnitude, occurrence rates, and timing. Peak‐over‐threshold sampling, modified Mann‐Kendall trend tests, and Poisson regression model were utilized in this study. Causes driving the observed statistical behaviours of EP were investigated, focusing particularly on the impacts of temperature change and the El Niño–Southern Oscillation (ENSO). EP events, which occur mainly during April and September, are most frequent in June. At an annual scale, they are subject to relatively even interannual distributions during the wet season. Significant trends were observed in the magnitude, frequency, and timing of EP events during the dry seasons, although no such trends were seen during the wet seasons. Seasonal shifts in EP can easily trigger sudden flood or drought events and warming temperatures, and ENSO events also have significant impacts on EP processes across the PRBC, as reflected by their increased magnitude and frequency in the western PRBC and decreased precipitation magnitudes in the eastern PRBC during ENSO periods. These results provide important evidence of regional hydrological responses to global climate changes in terms of EP regimes in tropical and subtropical zones. 相似文献
158.
Variation in soil saturated hydraulic conductivity along the hillslope of collapsing granite gullies 总被引:2,自引:0,他引:2
Saturated hydraulic conductivity (Ks) affects the soil hydrological process and is influenced by many factors that exhibit strong spatial variations. To accurately measure Ks and its scale, spatial variability and relationship with collapsing gullies, we analysed four double-ring infiltrometer diameters in three soil layers during in situ experiments designed to measure Ks in two typical collapsing gullies (three slope sites) in Tongcheng County of China. The results showed that Ks increased with increasing inner ring diameter, but no significant difference existed between inner diameters of 30 and 40 cm. The Ks in red soil layers was higher than that in sandy soil layers, the transition layers had the lowest values. Ks also varied with slope position, gradually decreasing with distance from the gully head. The suggestion is that the spatial variation in Ks is affected not only by the intrinsic soil properties but also by the interaction with the collapsing gully. 相似文献
159.
针对数字化地震台网JOPENS软件系统的技术特点及功能需求,在对当前各种主流云计算平台进行比较的基础上,基于较为合适的阿里云计算平台,提出了在云环境下部署JOPENS系统的应用方案。测试结果表明JOPENS系统部署在云环境下能够提升测震台网中心运行的稳定性及可扩展性,并节约运行维护成本。该研究对于当前三网融合新形势下云南省地震台网的建设及运行工作具有借鉴意义。 相似文献
160.
The focal mechanism solution on the seismic fault plane can reflect the geometric and kinematic characteristics of faults, and it is an important way to further study the fine structure of fault plane. From the focal mechanism solution of the earthquakes around the Dujiangyan fault in Longmenshan fault zone, we derived the average dip angle of Dujiangyan fault is 45.1° based on the seismic moment tensor theory. In order to refine the fault geometry structure, this paper decomposed it into multiple sub-fault planes along the length and width of the fault plane and forms a number of models A13, B13, A23 a, A23 b, A23 c, B23 a,B23 b and B23 c, then calculated the sub-fault's dip of each model. In order to clarify exactly which one of the fault models is closest to the real fault model, the fault slip was carried out for each model in turn, then compared the surface displacement of each model with GPS observations. The results show that B23 c model with high dip in shallow and small dip in deep is the best model, the lengths of each subfault of Dujiangyan fault from south to north are 33 km, 21 km and 46 km, respectively. When the depth of the fault bottom is about 11 km, the dip angles are 70.56°, 67.41° and 45.55°.When the depth of the fault bottom is about 30 km, The fault dip angles are 44.55°, 29.18° and 44.25°. 相似文献