【摘要】 龙门山北部3条不同走向的断裂带所围限的三角地区是我国陕甘川交界地区研究地震活动的重要场所.通过对区内秦岭南缘断裂、平武—青川断裂、岷江断裂及虎牙断裂活动特征研究和活动时代分析认为:秦岭南缘断裂,包括迭部—舟曲断裂、武都—康县—略阳断裂及茶店—勉县断裂在晚更新世曾有过活动,在全新世活动不明显;龙门山断裂带东北段平武—青川断裂最后一次活动发生在晚更新世,表现为右旋走滑的逆断裂,全新世活动不明显;岷江断裂和虎牙断裂不但在晚更新世活动强烈,而且在全新世继续活动;龙门山北部这个三角地区依然是未来地震活动关注的重点地区.更多还原

【Abstract】 The triangle structure area surrounded by three different strike fault zones in northern part of Longmenshan is one of the important areas associated with earthquake activity in China.This paper studies the activity characteristics and active age of some primary fault zones,such as the southern margin fault zone of Qinling,Pingwu--Qingchuan fault,Minjiang fault and Huya fault.The conclusions are as follows:① The southern margin fault zone of Qinling is composed of Diebu--Zhouqu fault,Wudu--Kangxian--Lüeyang fault and Chadian--Mianxian fault.The last fault activity was in Late Pleistocene and faults were steady in Holocene.② Pingwu--Qingchuan fault in northeastern segment of Longmenshan fault zone is a thrust fault with dextral strike-slip component.The last fault activity was in Late Pleistocene and steady in Holocene.③ Minjiang fault and Huya fault were strongly active from Pleistocene to Holocene.④This area is still one of important areas for studying earthquake activity in the future.更多还原