吉林大椅子山火山年代学、地球化学特征及其排气量的估算

Chronological and Geochemical Features and Degassing Evaluation of the Dayizishan Volcano,Jilin Province

利用铀系组分法测得龙岗大椅子山火山喷发时间为距今 71± 9ka,属于晚更新世。各类喷发物的岩石化学、地球化学特征表明 ,它们形成于同一岩浆源。根据岩石学方法 ,结合Thordarson (1996 )等人的排气模型 ,估算此次喷发向大气层输送的HCl、HF总量分别为 7.36Mt和 5 .2 1Mt。

According to the analysis by U-series component method,Dayizishan volcano erupted at 71±9 ka B P in late Pleistocene. Petrochemical and geochemical features of the eruption products of all phases imply that they came from the same magma resource. Based on petrological methods and the degassing model devised by Thordarson in 1996,It is estimated from the measured chlorine and fluorine concentrations in the samples that the atmospheric loading of hydrochloric acid and that of hydrofluoric acid were 7.36 Mt and 5.21 Mt,respectively.