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泰国北部清孔地区存在着大量的火山岩,前人将其划归二叠纪-三叠纪.运用LA-ICP-MS的方法,对清孔地区代表性的火山岩进行了锆石U-Pb年代学研究.其中Doi Yao带玄武质安山岩TL-1-B和TL-31-B锆石年龄分别为241.1±6.9Ma和241.1±3.9Ma,Doi Khun Ta Khuan带流纹岩TL-32-B1锆石年龄为238.0±8.9Ma,三者均为中三叠世早期.这组U-Pb同位素年龄与云南景洪地区和泰国南邦地区的弧火山形成年龄相近,指示泰国北部清莱弧火山岩带从南邦地区,经清孔地区,向北延伸到了景洪地区的澜沧江弧火山岩带.另外,研究区还发现(1885±16～1323±13)Ma的U-Pb同位素年龄,表明该区存在古元古代-中元古代的基底.
There are a large number of volcanic rocks in the Qing Kong area in northern Thailand, which were formerly assigned to Permian-Triassic. Using the method of LA-ICP-MS, the representative volcanic rocks in the Qing Kong area were subjected to zircon U-Pb dating The zircon ages of the TL-1-B and TL-31-B zircons from the Doi Yao basaltic andesite are 241.1 ± 6.9Ma and 241.1 ± 3.9Ma, respectively. The zircons of the TL-32-B1 zircon from the Doi Khun Ta Khuan The stone age is 238.0 ± 8.9Ma, all of them are in the early Middle Triassic.The ages of U-Pb isotopes in this group are similar to the age of arc volcanoes in Jinghong, Yunnan and Lampang, Thailand, indicating that the volcanic belt From Lampang region to Qingkou region, it extends northward to the Lancangjiang arc volcanic belt in Jinghong area.In addition, the U-Pb isotopic age of (1885 ± 16 ~ 1323 ± 13) Ma was also found in the study area, indicating the existence of this area Ancient Paleo - Mesozoic basement.