气候变化领域集成服务门户(CCPortal): A 14.5-million-year record of East Antarctic Ice Sheet fluctuations from the central Transantarctic Mountains, constrained with cosmogenic 3He, 10Be, 21Ne, and 26Al

CCPortal

DOI	10.5194/tc-14-2647-2020
	A 14.5-million-year record of East Antarctic Ice Sheet fluctuations from the central Transantarctic Mountains, constrained with cosmogenic 3He, 10Be, 21Ne, and 26Al
	Balter-Kennedy A.; Bromley G.; Balco G.; Thomas H.; Jackson M.S.
发表日期	2020
ISSN	19940416
起始页码	2647
结束页码	2672
卷号	14 期号:8
英文摘要	The distribution of moraines in the Transantarctic Mountains affords direct constraint of past ice-marginal positions of the East Antarctic Ice Sheet (EAIS). Here, we describe glacial geologic observations and cosmogenic-nuclide exposure ages from Roberts Massif, an ice-free area in the central Transantarctic Mountains. We measured cosmogenic 3He, 10Be, 21Ne, and 26Al in 168 dolerite and sandstone boulders collected from 24 distinct deposits. Our data show that a cold-based EAIS was present, in a configuration similar to today, for many periods over the last ∼ 14.5 Myr, including the mid-Miocene, late Pliocene, and early to Middle Pleistocene. Moraine ages at Roberts Massif increase with distance from, and elevation above, the modern ice margin, which is consistent with a persistent EAIS extent during glacial maxima and slow, isostatic uplift of the massif itself in response to trough incision by outlet glaciers.We also employ the exceptionally high cosmogenic-nuclide concentrations in several boulders, along with multi-isotope measurements in sandstone boulders, to infer extremely low erosion rates (≪5 cm Myr-1) over the period covered by our record. Although our data are not a direct measure of ice volume, the Roberts Massif glacial record indicates that the EAIS was present and similar to its current configuration during at least some periods when the global temperature was believed to be warmer and/or atmospheric CO2concentrations were likely higher than today. © 2020 American Society of Civil Engineers (ASCE). All rights reserved.
英文关键词	aluminum; beryllium isotope; cosmogenic radionuclide; glacioisostasy; helium isotope; historical record; Miocene; moraine; neon; paleoclimate; paleoenvironment; Pleistocene; Pliocene; Antarctic Ice Sheet; Antarctica; East Antarctic Ice Sheet; East Antarctica; Transantarctic Mountains
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202023
作者单位	School of Earth and Climate Sciences, University of Maine, Orono, ME, United States; Climate Change Institute, University of Maine, Orono, ME, United States; Geography, National University of Ireland Galway, Galway, Ireland; Berkeley Geochronology Center, Berkeley, CA, United States
推荐引用方式 GB/T 7714	Balter-Kennedy A.,Bromley G.,Balco G.,et al. A 14.5-million-year record of East Antarctic Ice Sheet fluctuations from the central Transantarctic Mountains, constrained with cosmogenic 3He, 10Be, 21Ne, and 26Al[J],2020,14(8).
APA	Balter-Kennedy A.,Bromley G.,Balco G.,Thomas H.,&Jackson M.S..(2020).A 14.5-million-year record of East Antarctic Ice Sheet fluctuations from the central Transantarctic Mountains, constrained with cosmogenic 3He, 10Be, 21Ne, and 26Al.Cryosphere,14(8).
MLA	Balter-Kennedy A.,et al."A 14.5-million-year record of East Antarctic Ice Sheet fluctuations from the central Transantarctic Mountains, constrained with cosmogenic 3He, 10Be, 21Ne, and 26Al".Cryosphere 14.8(2020).