河北平原第四纪火山岩时代

Timing of Quaternary volcanic rocks in Hebei plain

摘要: 提要: 河北平原第四纪火山岩时代对理解华北东部新构造运动具有重要意义, 但是对其准确年龄一直缺少研究。位于河北省海兴县附近CK3孔岩心揭示了4次第四纪的火山活动。针对第1次火山岩底部样品开展40Ar/ 39Ar测试, 其年龄为(2.36 ± 0.05) Ma。结合磁性地层研究结果, 限定了其他3次火山活动时代分别为约1.3 Ma、35~70 ka和10~15 ka。

Abstract: Abstract: It is important to date the Quaternary volcanic rocks for understanding the neotectonic activities in Hebei plain. The 500.25 meter drill hole CK3 located near Haixing Country of Hebei Province revealed 4 layers of volcanic rocks. The 40Ar/39Ar age of the first stage of Quaternary volcanic rocks is 2.36±0.05 Ma. Combined with the magnetostratigraphy of CK3 core, the time of volcanic activities in Hebei Plain should be about 1.3 Ma, 35?70 ka and 10?15 ka, respectively.