Deglaciation and weathering of Larsemann Hills, East Antarctica
Deglaciation and weathering of Larsemann Hills, East Antarctica
复制标题
DOI：
10.1017/s0954102009002028
复制
发表时间：
2009-08
影响因子：
1.6
通讯作者：
K. Kiernan;D. Gore;D. Fink;D. White;A. McConnell;I. A. Sigurdsson
中科院分区：
文献类型：
--
作者：
K. Kiernan;D. Gore;D. Fink;D. White;A. McConnell;I. A. Sigurdsson
摘要原位宇宙成因10 Be暴露测年、放射性碳测定、盐和沉积物地球化学以及岩石风化观测表明，东南极拉斯曼丘陵的部分地区在末次冰期循环的大部分时间里一直暴露在地表下，末次冰期发生在100 ka bp之前。盐增强的陆上风化，加上缺乏冰川erratics，暴露年龄测定具有挑战性。在某些地方，快速的地表下降意味着某些暴露年龄可能低估了真正的冰川消退年龄。尽管存在这种不确定性，但这些数据与末次冰期最大冰盛期（距今20-18 ka bp）没有被厚冰盖覆盖的情况是一致的。
Abstract In situ cosmogenic 10Be exposure dating, radiocarbon determinations, salt and sediment geochemistry, and rock weathering observations indicate that parts of Larsemann Hills, East Antarctica have been subaerially exposed throughout much of the last glacial cycle, with the last glaciation occurring prior to 100 ka bp. Salt-enhanced subaerial weathering, coupled with a paucity of glacial erratics, made exposure age dating challenging. Rapid subaerial surface lowering in some places means that some exposure ages may underestimate the true age of deglaciation. Despite this uncertainty, the data are consistent with the absence of overriding by a thick ice sheet during the Last Glacial Maximum ∼20–18 ka bp.