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DOI	10.1002/esp.3765
	Defining rates of landscape evolution in a south Tibetan graben with in situ-produced cosmogenic Be-10
	Rades, Eike F.; Hetzel, Ralf; Strobl, Marcus; Xu, Qiang; Ding, Lin
通讯作者	Rades, EF (通讯作者)
发表日期	2015
ISSN	0197-9337
EISSN	1096-9837
起始页码	1862
结束页码	1876
卷号	40 期号:14
英文摘要	The Tangra Yum Co graben is one of the active structures that accommodate the east-west extension of the southern Tibetan Plateau and hosts one of the largest Tibetan lakes, which experienced lake-level changes of 200m during the Holocene. In this study, cosmogenic Be-10 is employed to: (1) quantify catchment-wide denudation rates in fault-bounded mountain ranges adjacent to the Tangra Yum Co graben; (2) date palaeo-shorelines related to the Holocene lake-level decline; and (3) determine the age of glacial advances in this region. The fault-bounded, non-glaciated mountain range north of Tangra Yum Co - and presumably most other areas around the lake - erode at low rates of 10-70mm/ka. Owing to the slow erosion of the landscape, the sediments delivered to Tangra Yum Co have high Be-10 concentrations. As a consequence, accurate exposure dating of sediment-covered terraces and beach ridges is difficult, because the pre-depositional Be-10 concentration may exceed the post-depositional Be-10 concentration from which exposure ages are calculated. This difficulty is illustrated by a rather inaccurate Be-10 exposure age of 2.3 +/- 1.4ka (i.e. an error of 60%) for a terrace that is located 67m above the lake. Nevertheless, the age is consistent with luminescence ages for a series of beach ridges and provides further evidence for the decline of the lake level in the late Holocene. At Tangra Yum Co exposure dating of beach ridges via Be-10 depth profiles is not feasible, because the pre-depositional Be-10 component in these landforms varies with depth, which violates a basic assumption of this approach. Be-10 ages for boulders from two moraines are much older than the early Holocene lake-level highstand, indicating that melting of glaciers in the mountain ranges adjacent to Tangra Yum Co has not contributed significantly to the lake-level highstand in the early Holocene. Copyright (c) 2015 John Wiley & Sons, Ltd.
关键词	PRODUCTION-RATE CALIBRATION DENUDATION RATES EXPOSURE AGES QUATERNARY GLACIATION BEDROCK PENEPLAIN FLUVIAL TERRACES BEACH RIDGES TANGRA YUMCO NAM CO PLATEAU
英文关键词	cosmogenic Be-10; denudation rate; exposure dating; glaciations; Tangra Yum Co; Tibet
语种	英语
WOS研究方向	Physical Geography ; Geology
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary
WOS记录号	WOS:000363702200002
来源期刊	EARTH SURFACE PROCESSES AND LANDFORMS
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/258547
推荐引用方式 GB/T 7714	Rades, Eike F.,Hetzel, Ralf,Strobl, Marcus,et al. Defining rates of landscape evolution in a south Tibetan graben with in situ-produced cosmogenic Be-10[J]. 中国科学院青藏高原研究所,2015,40(14).
APA	Rades, Eike F.,Hetzel, Ralf,Strobl, Marcus,Xu, Qiang,&Ding, Lin.(2015).Defining rates of landscape evolution in a south Tibetan graben with in situ-produced cosmogenic Be-10.EARTH SURFACE PROCESSES AND LANDFORMS,40(14).
MLA	Rades, Eike F.,et al."Defining rates of landscape evolution in a south Tibetan graben with in situ-produced cosmogenic Be-10".EARTH SURFACE PROCESSES AND LANDFORMS 40.14(2015).