Heavy noble gases (Ar/Xe/Kr) from ALHIC1901, 1902, and 1903 ...
Between about 2.8-0.9 Ma, Earth’s climate was characterized by 40 kyr cycles, driven or paced by changes in the tilt of Earth’s spin axis. Much is known about the 40k world from studies of deep-sea sediments, but our understanding of climate change during this period and the transition between the 4...
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| Format: | Dataset |
| Language: | English |
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U.S. Antarctic Program (USAP) Data Center
2025
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| Online Access: | https://dx.doi.org/10.15784/601895 https://www.usap-dc.org/view/dataset/601895 |
| Summary: | Between about 2.8-0.9 Ma, Earth’s climate was characterized by 40 kyr cycles, driven or paced by changes in the tilt of Earth’s spin axis. Much is known about the 40k world from studies of deep-sea sediments, but our understanding of climate change during this period and the transition between the 40kyr glacial cycles from 2.8-0.9 Ma and the 100kyr glacial cycles of the last 0.9 Myr is incomplete because we lack records of Antarctic climate and direct records of atmospheric greenhouse gas concentrations. We propose to address these issues by building on our recent studies of >1 Ma ice discovered in shallow ice cores in the Allan Hills Blue Ice Area (BIA), Antarctica. During the 2015-2016 field season we recovered ice from two nearby drill cores that dates to > 2 million years in age using the 40Ar/38Ar ratio of the trapped gases. Our discovery of ice of this antiquity in two cores demonstrates that there is gas-record quality ice from the 40k world in the Allan Hills BIA. To further characterize the ... |
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