期刊
QUATERNARY SCIENCE REVIEWS
卷 203, 期 -, 页码 90-101出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.quascirev.2018.10.018
关键词
Varve; Geochronology; Age model; Tephra; Alaska
资金
- NSF [1418000, 1602106]
- Research Foundation Flanders (FWO-Vlaanderen grant) [G042812N]
- Directorate For Geosciences
- Division Of Earth Sciences [1602106] Funding Source: National Science Foundation
- Office of Polar Programs (OPP)
- Directorate For Geosciences [1418000] Funding Source: National Science Foundation
Developing robust chronological frameworks of lacustrine sediment is central to reconstructing past environmental changes. We present varve chronologies from five sites extending back 2300 years from Eklutna Lake, in the Chugach Mountains of south-central Alaska. The chronologies are built from image analysis of high-resolution photographs and CT scans of sediment cores. The age uncertainty of each record is tested by three methods. We first present varve chronologies from individual sites and reconcile the difference in varve delimitation from two observers. The varve chronologies from each site are then compared to each other using a series of marker beds that can be traced across the lake basin. Finally, using a new Bayesian probabilistic model, we develop age models that incorporate information regarding age uncertainty from the multiple-observer method and the age distribution of marker layers from multiple cores. To evaluate the accuracy of the Bayesian model output, we used seven radiocarbon ages from terrestrial macrofossils and four tephra layers traceable across the core sites. The major-element geochemistry of the tephra layers and their ages are presented here for the first time. The Bayesian age model offers a new approach to quantifying age uncertainty in inter-correlated cores of varved sediment. (C) 2018 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据