Late Quaternary tephrostratigraphy of southern Chile and Argentina

QUATERNARY SCIENCE REVIEWS

卷:89

Article

Fontijn, Karen¹  Lachowycz, Stefan M.¹  Rawson, Harriet¹  Pyle, David M.¹  Mather, Tamsin A.¹  Naranjo, Jose A.²  Moreno-Roa, Hugo³ 

[1] Univ Oxford, Dept Earth Sci, Oxford OX1 3AN, Oxon, England

[2] Serv Nacl Geol & Min, Santiago, Chile

[3] Serv Nacl Geol & Min, Observ Volcanol Los Andes Sur, Temuco, Chile

关键词: Tephra;    Tephrostratigraphy;    Tephrochronology;    Southern Volcanic Zone;    Austral Volcanic Zone;    Andes;    Patagonia;    Lake sediment core;    Peat core;    Tephra correlation;    Tephra preservation;   

DOI  :  10.1016/j.quascirev.2014.02.007

来源: Elsevier

【 摘 要 】

The Southern and Austral Volcanic Zones of the Andes comprise 74 volcanic centres with known postglacial activity. At least 21 of these have had one or more large explosive eruptions in the late Quaternary, dispersing tephra over vast areas. These tephra layers therefore have great potential as tephrochronological marker horizons in palaeoenvironmental studies in southern Chile and Argentina, a region that is particularly useful to study climate dynamics of the southern hemisphere. However, to date tephrochronology has rarely been fully utilised in this region as a correlation and dating tool. Here we review the existing post-glacial tephrostratigraphic record of the Southern and Austral Volcanic Zones, and compile a database of known occurrences of tephra from these volcanoes in ice and lacustrine, marine, peat, and cave sediment records. We address the inconsistencies in and revisions of the tephrostratigraphies presented in prior literature, and discuss the challenges in correlating tephras and the limitations of the tephrostratigraphic record in this area. This study highlights the many gaps that still exist in our knowledge of the eruptive histories of these volcanoes, but also reveals the largely underutilised potential of tephra as a correlation tool in this region. This is exemplified by the severe lack of adequate geochemical analysis of tephra layers preserved in many lacustrine and peat sediment sections, which are particularly important tephrostratigraphic records in southern Chile and Argentina due to the paucity of surface preservation. (C) 2014 The Authors. Published by Elsevier Ltd.

【 授权许可】

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