An ice core is a core sample that is typically removed from an ice sheet or a high mountain glacier.
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15 Facts About Ice core
2.
An ice core is a vertical column through a glacier, sampling the layers that formed through an annual cycle of snowfall and melt.
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3.
Ice core is lost at the edges of the glacier to icebergs, or to summer melting, and the overall shape of the glacier does not change much with time.
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4.
Since retrieval of each segment of Ice core requires tripping, a slower speed of travel through the drilling fluid could add significant time to a project—a year or more for a deep hole.
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5.
The Ice core barrel is hoisted to the surface, and the Ice core removed; the barrel is lowered again and reconnected to the drill assembly.
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6.
The Ice core is then extracted from the drill barrel, usually by laying it out flat so that the Ice core can slide out onto a prepared surface.
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7.
The Ice core must be cleaned of drilling fluid as it is slid out; for the WAIS Divide coring project, a vacuuming system was set up to facilitate this.
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8.
The surface that receives the Ice core should be aligned as accurately as possible with the drill barrel to minimise mechanical stress on the Ice core, which can easily break.
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9.
The Ice core is then bagged, often in polythene, and stored for shipment.
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10.
Isotopic composition of the oxygen in a core can be used to model the temperature history of the ice sheet.
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11.
Dragging them down the length of the Ice core, and recording the conductivity at each point, gives a graph that shows an annual periodicity.
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12.
Vostok 3 was the first core to retrieve ice from the previous glacial period, 150,000 years ago.
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13.
The Dome C Ice core had very low accumulation rates, which mean that the climate record extended a long way; by the end of the project the usable data extended to 800,000 years ago.
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14.
The cores were dated by potassium-argon dating; traditional ice core dating is not possible as not all layers were present.
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15.
The Ice core provided climatic data back to 123,000 years ago, which covered part of the last interglacial period.
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