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矿物和结构分析揭示了南极洲乔治王岛柯林斯冰帽一支 80 .2 m冰芯中的 9层深褐色沉积物的火山灰特征。本文从冰川处于稳定状态的假定出发 ,根据 Dansgaard- Johnsen流动模式断代结果 ,建立了南设得兰群岛火山喷发序列。依冰芯记录判断 ,该区 1 650年以来的 340年间 ,共有 7轮火山喷发。1 875～ 1 92 5年间似为火山活跃期 ,喷发地点可能主要在欺骗岛 ;1 650～ 1 80 0年间为一相对平静期 ;此后一个世纪不太稳定 ;而过去的 1 0 0年间基本平静 ,只是世纪初和 50～ 70年代间各有一段动荡期。冰芯中记载的大多数火山喷发可在该区有关文献中找到记录。没有记录在案的几例喷发事件需进一步调查。冰芯中缺失 1 967～ 1 970年欺骗岛火山灰层位表明 ,研究得到的火山序列仍未包含所有的喷发事件。但本文展示的该区过去 340年间火山活动基本趋势并不因此而改变。
Mineralogy and structural analysis revealed volcanic ash characteristics of nine deep-seated sediments in an 80.2-m ice core of the Collins ice cap in the Island of George in Antarctica. Based on the assumption that the glacier is in a stable state, the South Shetland volcanic eruption sequence was established based on the Dansgaard-Johnsen flow pattern dating. Judging from Bing Bing’s records, a total of seven volcanic eruptions occurred in 340 years since 1 650 in the area. 1875-1 92 years as a volcano active period, the eruption may be mainly deception island; 1 650 ~ 180 years as a relative calm period; after a century is not very stable; the past 100 years of basic calm , But there was a period of turmoil between the beginning of the century and the 1950s and 1970s. Most volcanic eruptions recorded in ice cores can be found in the relevant literature in this area. There are no documented cases of eruptions requiring further investigation. The absence of delusional volcanic ash from 1967 to 1970 in the ice core indicates that the volcanic sequence obtained from the study did not yet contain all the eruptions. However, the basic trend of volcanic activity in the past 340 years in this area is not shown in this article.