排序方式： 共有150条查询结果，搜索用时 31 毫秒
141.
中央气象局气象科学研究所数值预报组 《气象学报》1959,30(4):398-404
通过对实际资料的分析,作者发现,在0—70°N 地区北半球500mb 气候平均位势高度沿纬圈的平均值,不论冬夏,都可以很准确地用四参数来表示,其误差小于10位势米.对用三参数和二参数表示的情况也作了此较.最后还用三参数计算了逐月的气候平均情况和个别月份逐日的情况,并指出了某些特征. 相似文献
142.
用球函数展开北半球地形的计算 总被引：2，自引：0，他引：2
中央气象局气象科学研究所数值预报组 《气象学报》1959,30(4):405-413
通过计算,如取m≤36,n—m≤20,北半球地形一般可以相当精确地用球函数来表示.计算表明,除高纬度地区外,地形高度沿纬圈平均的相对误差都在0.33%以下.在计算过程中,作者还给出了检查错误的公式.对计算结果也进行了讨论. 相似文献
143.
西北地震综合预报清理攻关组 《地震工程学报》1989,11(2):61-69
本文初步总结了西北地区近十几年来地震综合预报的探索与进展。结果表明,在中长期趋势预测方面,对多数5级以上破坏性地震已具有测震学监测基础,综合预测结果基本上通过了统计检验;在短临预测方面仅对乌鲁木齐地区和兰州、银川、西安和武都范围以内发生的6 1/2级以上地震具有初步的监测基础。由19个震例获得以测震学资料为主的中长期趋势异常共73项,以地下水位、水氧、地电和地磁资料为主的短临异常共59项。本文概述了有关异常的特征和综合预报思路,讨论了有关问题和动向。 相似文献
144.
用哈佛CMT目录和中国地震震源机制目录给出了地震矩张量元素Mrr的符号的空间分布。这种空间分布图像相当于Tanimoto等 ( 2 0 0 0 )的“地壳势能变化”的空间分布图像的一种简化形式 ,Mrr的符号代表了地震震源处的应力状态。之所以进行这种简化是因为在相当多的情况下 ,地震的震源或矩心深度难以测准 ,并且震源机制目录的完整性得不到保证。将Mrr的分布图像与中国大陆岩石层地块的分布图像进行对照 ,可以发现由Mrr标志的地块内部的应力状态具有相当的一致性。地块边缘处的应力状态与地块内部的应力状态不同 ,似乎表明地块本身具有一定的整体性 ,同时地块之间存在相对运动 相似文献
145.
中国地壳运动速度场--GAMIT和GISPY解算结果比对 总被引：17，自引：9，他引：8
采用"中国地壳运动观测网络"区域网1999、2001年的观测资料,利用GAMIT和GIPSY解出了测站位移速度值,并对这两种解算结果进行了对比分析.在920个观测站中,位移速度差东西、南北分量的平均值分别为(0.25±0.08) mm/a与(1.33±0.07) mm/a,服从(0.2,2.3)、(1.3,2.2)正态分布,两者无大系统差异,但大约2/3的测站速度差幅度在2～6 mm/a之间.导致速度场差异的原因可能是实现统一参考框架的误差和观测时间间隔不长对季节性地壳变动的放大作用等. 相似文献
146.
伽师地区现今地壳运动方式、变动幅度和形变应变特征对研究该地区孕震环境具有重要作用．利用1994和1998年两次GPS大地测量,我们监测到伽师地区相对于北天山哈萨克地块的地壳缩短速率大约为19mm/a,与20世纪以来地震学（地震矩张量）资料估计的速率（约13mm/a）相比,GPS测定的速率高约50％．大地测量与地震学对南天山（伽师）地区地壳运动速率的估值差异,既可能说明该地区20世纪以来存在大量无震、震间应变,也可能表示至今与地震活动有关的断层变动尚不足以消减整个天山地区的现今变形．无论何种可能,从应力应变积累的角度看,都意味着天山西段及帕米尔东北侧一带发生强震的可能性将长期存在． 相似文献
147.
Zhang Guomin Li Li and Jiao MingruoCenter for Analysis Prediction CSB Beijing China 《中国地震研究》1999,(2)
Seismological approaches used in earthquake prediction involve many subjects. To predict large earthquakes from small to moderate foreshocks has a clear meaning in physics. Some of the main methods of earthquake prediction used in China are outlined in this paper. According to the anomalies used for earthquake prediction, seismological approaches can be divided into two groups: those that use the anomalies in seismic patterns, including the increase and decrease in regional seismicity, the appearance of seismic gaps, seismic belts, seismic swarms, and foreshocks and those that use anomalies in special values and in seismic waves, such as the anomalies in b values and f values, in the Vp/VS ratio, Q values, stress drop, and shear stress. 相似文献
148.
Wang Chengmin Zhou Shengkui Zhao Yi Wang Wei Chen Ronghua Xu Daoyi Ma Li Huang Wei and Geng JunjunCenter for Analysis Prediction CSB Beijing China SeismoIogical Bureau of Heilongjiang Province Harbin China Seismological Bureau of Shanghai Municipality Shanghai China Institute of Geology CSB Beijing China 《中国地震研究》1999,(3)
The level of present understanding of earthquake prediction of seismologists at home and abroad is very different. This is because China has opened up a special path of earthquake prediction research that has not been explored by other countries, with its own advantages and potentialities.Therefore, we considered that it is the most practical way to use the advantages and potentialities for raising the earthquake prediction level. For this purpose, we have developed a set of intelligent decision support system for earthquake prediction, with the analysis of cluster anomalies process at the core. The facts show that it can obviously raise the level of synthetic earthquake prediction. 相似文献
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150.
GUO Fuxiang Research Centre of Prediction of Hidden Ore Deposits Guilin Institute of Technology Guilin 《《地质学报》英文版》2000,74(1):1-6
The Kazakhstanian plate was near the Tarim, Sino-Korean and South China-Southeast Asian plates in the Middle-Late Cambrian and Late Ordovician, and approached the Siberian plate in the other periods of the Early Palaeozoic. The Hi and Toksun-Yamansu terranes had been split from the Tarim plate before the Middle Devonian and then went close to Angaraland in the late Early Permian. The Beishan area on the northeastern margin of the Tarim plate came close to Angaraland first in the early Early Permian. The suturing age between the Tarim and Ka-zakhstanian-Siberian plates is generally the same as that between the Turkey-Central Iran-Gangdise and South China-Southeast Asian plates. The suturing event took place in the early Early Permian, while the corresponding tectogeny occurred between the Early and Late Permian. 相似文献