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祁连山西端GL值动态演化特征与强震预测
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作者 苏宏伟 肖淑娟 《地震地磁观测与研究》 2012年第5期40-43,共4页
用地震活动非均匀度GL值作参数,使用1980—2011年祁连山西端M≥3.0地震资料进行GL值的空间扫描。结果表明,祁连山地区74%的M≥5地震前1—2年,在未来震中周围均有GL值异常出现,用R值对其进行评分,可以通过检验。
关键词 GL值方法 M≥5地震 中短期预测 祁连山西端
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阿尔金断裂东端白垩纪火山岩地球化学特征及其地质意义 被引量:10
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作者 汤文豪 张志诚 +2 位作者 李建锋 晨辰 李可 《地学前缘》 EI CAS CSCD 北大核心 2012年第4期51-62,共12页
在阿尔金断裂与祁连山北缘逆冲断裂交汇处的昌马盆地和酒西盆地内,产出一套中基性火山岩,多为玄武岩和粗面玄武岩,属于碱性玄武岩系列。火山岩富集轻稀土元素,(La/Yb)N比值为7.28~18.01,富集大离子亲石元素(K、Rb和Ba等),亏损高场强元... 在阿尔金断裂与祁连山北缘逆冲断裂交汇处的昌马盆地和酒西盆地内,产出一套中基性火山岩,多为玄武岩和粗面玄武岩,属于碱性玄武岩系列。火山岩富集轻稀土元素,(La/Yb)N比值为7.28~18.01,富集大离子亲石元素(K、Rb和Ba等),亏损高场强元素(Nb、Ta等),显示出与OIB类似的地球化学特征。阿尔金断裂带东端火山岩的Sr同位素较高,87Sr/86Sr值在0.706~0.708,Nd同位素较低,εNd(t)值多为负值(0.53~-6.13),显示出EMⅡ型富集地幔来源的特征。K-Ar同位素年代学测试结果表明,阿尔金断裂带东端火山岩形成于(120.1±2.5)~(102.2±2.9)Ma,属于早白垩世晚期。火山岩的地球化学特征反映其形成于一个广泛的陆内伸展环境中,区域上可能受到阿尔金断裂带的影响,是阿尔金断裂白垩纪再活化的重要佐证。 展开更多
关键词 火山岩 早白垩世 K-Ar年代学 阿尔金断裂带 祁连山西端
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Temporal and spatial variations in extreme temperatures in the Qilian Mountains-Hexi Corridor over the period 1960-2013 被引量:1
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作者 JIA Wen-xiong 《Journal of Mountain Science》 SCIE CSCD 2016年第12期2224-2236,共13页
Based on daily maximum and minimum temperatures at 18 meteorological stations in the Qilian Mountains and Hexi Corridor between 1960 and 2013,temporal and spatial variations in extreme temperatures were analysed using... Based on daily maximum and minimum temperatures at 18 meteorological stations in the Qilian Mountains and Hexi Corridor between 1960 and 2013,temporal and spatial variations in extreme temperatures were analysed using linear trends,tenpoint moving averages and the Mann-Kendall test.The results are as follows:The trends in the majority of the extreme temperature indices were statistically significant,and the changes in the extreme temperatures were more obvious than the changes in the extreme values.The trends were different for each season,and the changes in rates and intensities in summer and autumn were larger than those in spring and winter.Unlike the cold indices,the magnitudes and trends of the changes in the warm indices were larger and more significant in the Hexi Corridor than in the Qilian Mountains.Abrupt changes were detected in the majority of the extreme temperature indices,and the extreme cold indices usually occurred earlier than the changes in the extreme warm indices.The abrupt changes in the extreme temperatures in winter were the earliest among the four seasons,indicating that these temperature changes were the most sensitive to global climate change.The timing of the abrupt changes in certain indices was consistent throughout the study area,but the changes in the cold indices in the Hexi Corridor occurred approximately four years before those in the Qilian Mountains.Similarly,the changes in the warm indices in the western Hexi Corridor preceded those of the other regions. 展开更多
关键词 Extreme temperature Interannual change Climate change Qilian Mountains Hexi Corridor
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