A Top-to-Bottom Luminescence-Based Chronology for the Post-LGM Regression of a Great Basin Pluvial Lake
A Top-to-Bottom Luminescence-Based Chronology for the Post-LGM Regression of a Great Basin Pluvial Lake
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DOI：
10.3390/quat3020011
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发表时间：
2020-04
期刊：
影响因子：
2.3
通讯作者：
J. Munroe;C. Walcott;W. Amidon;J. Landis
中科院分区：
文献类型：
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作者：
J. Munroe;C. Walcott;W. Amidon;J. Landis
本文对美国内华达州东北部的三叶草湖在末次冰期形成的一系列海岸线进行了释光测年。在最大的范围内，该湖面积为740平方公里，平均深度为16米，水量为13立方公里。湖盆中北部有10个明显的海滩脊从高位延伸到最低岸线，水平距离约1.5 km，湖泊面积减少了35%。这些山脊主要由桑迪砾石组成，高出它们所叠加的冲积扇表面约1.0 m。单颗粒发光测年的钾长石使用pIRIR SAR（后红外线红外线单等分再生剂量）协议，证实了SAR测年的石英，表明高水位海岸线建造约。16-17 ka在海因里希Stadial I（格陵兰Stadial 2，GS-2），匹配14 C年龄控制在盆地其他地方的海岸线。该湖在博灵/阿勒罗德（GI-1）期间迅速消退，在新仙女木时期（GS-1）消退速度放缓之前。最低的海岸线是由约。十公里三叶草湖到全新世早期的持久性可能反映了夏季日照最大值驱动的季风降水增强。
We applied luminescence dating to a suite of shorelines constructed by pluvial Lake Clover in northeastern Nevada, USA during the last glacial cycle. At its maximum extent, the lake covered 740 km2 with a mean depth of 16 m and a water volume of 13 km3. In the north-central sector of the lake basin, 10 obvious beach ridges extend from the highstand to the lowest shoreline over a horizontal distance of ~1.5 km, representing a lake area decrease of 35%. These ridges are primarily composed of sandy gravel and rise ~1.0 m above the alluvial fan surface on which they are superposed. Single grain luminescence dating of K-feldspar using the pIRIR SAR (post-infrared infrared single-aliquot regenerative dose) protocol, corroborated by SAR dating of quartz, indicates that the highstand shoreline was constructed ca. 16–17 ka during Heinrich Stadial I (Greenland Stadial 2, GS-2), matching 14C age control for this shoreline elsewhere in the basin. The lake regressed rapidly during the Bølling/Allerød (GI-1), before the rate of regression slowed during the Younger Dryas interval (GS-1). The lowest shoreline was constructed ca. 10 ka. Persistence of Lake Clover into the early Holocene may reflect enhanced monsoonal precipitation driven by the summer insolation maximum.