Abstract: The Weizhou Island is a volcanic island in the Beibu Bay. Volcanic activity on the island can be roughly divided into two stages, mainly in the Early-Middle Pleistocene and the Late Pleistocene separately. Eruptions of the Nanwan Volcano (late stage activity of Weizhou Volcanic Province) were typical phreatomagmatic eruptions, forming a big maar and thick ring walls of pyroclastics and debris. In this paper, we reported the OSL dating result of the sandstone xenoliths, which were trapped in the two volcanic pyroclastic layers of the Nanwan Volcano. The ages revealed that the activity of the Nanwan Volcano mainly occurred in ca 30ka ago, at the end of the Late Pleistocene.

Key words: the Beibu Bay, Nanwan Volcano, sandstone xenolith, OSL dating

摘要： 涠洲岛是北部湾内的一座火山岛,火山活动初步可以分为早-中更新世和晚更新世2期。晚期南湾火山是典型的射气岩浆喷发成因的火山,文中报道了南湾火山的上、下2层火山碎屑岩中砂岩捕虏体的光释光(OSL)测年结果,提出南湾火山喷发时代为距今约3万年左右的晚更新世末期。

关键词: 北部湾涠洲岛, 南湾火山, 砂岩捕虏体, 光释光(OSL)测年