Katla (Icelandic pronunciation: [ˈkʰaʰtla]) is a large volcano in southern Iceland. It is very active; twenty eruptions have been documented between 930 and 1918, at intervals of 20–90 years. It has not erupted violently for 103 years, although there may have been small eruptions that did not break the ice cover, including ones in 1955,1999, and 2011.

^{https://en.wikipedia.org/wiki/Katla_(volcano)}

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28,560 seconds 

Ice core dates A difficulty in ice core dating is that gases can diffuse through firn, so the ice at a given depth may be substantially older than the gases trapped in it. As a result, there are two chronologies for a given ice core: one for the ice, and one for the trapped gases. To determine the relationship between the two, models have been developed for the depth at which gases are trapped for a given location, but their predictions have not always proved reliable.^[39][40] At locations with very low snowfall, such as Vostok, the uncertainty in the difference between ages of ice and gas can be over 1,000 years.

Soviet ice drilling projects began in the 1950s, in Franz Josef Land, the Urals, Novaya Zemlya, and at Mirny and Vostok in the Antarctic; not all these early holes retrieved cores.^[108] Over the following decades work continued at multiple locations in Asia.^[109] Drilling in the Antarctic focused mostly on Mirny and Vostok, with a series of deep holes at Vostok begun in 1970.^[110] The first deep hole at Vostok reached 506.9 m in April 1970; by 1973 a depth of 952 m had been reached. A subsequent hole, Vostok 2, drilled from 1971 to 1976, reached 450 m, and Vostok 3 reached 2202 m in 1985 after six drilling seasons.^[111] Vostok 3 was the first core to retrieve ice from the previous glacial period, 150,000 years ago.

https://en.wikipedia.org/wiki/Ice_core

Katla (Icelandic pronunciation: [ˈkʰaʰtla]) is a large volcano in southern Iceland. It is very active; twenty eruptions have been documented between 930 and 1918, at intervals of 20–90 years. It has not erupted violently for 103 years, although there may have been small eruptions that did not break the ice cover, including ones in 1955,1999, and 2011.

^{https://en.wikipedia.org/wiki/Katla_(volcano)}

5,400 seconds 

28,560 seconds 

Ice core dates A difficulty in ice core dating is that gases can diffuse through firn, so the ice at a given depth may be substantially older than the gases trapped in it. As a result, there are two chronologies for a given ice core: one for the ice, and one for the trapped gases. To determine the relationship between the two, models have been developed for the depth at which gases are trapped for a given location, but their predictions have not always proved reliable.^[39][40] At locations with very low snowfall, such as Vostok, the uncertainty in the difference between ages of ice and gas can be over 1,000 years.

Soviet ice drilling projects began in the 1950s, in Franz Josef Land, the Urals, Novaya Zemlya, and at Mirny and Vostok in the Antarctic; not all these early holes retrieved cores.^[108] Over the following decades work continued at multiple locations in Asia.^[109] Drilling in the Antarctic focused mostly on Mirny and Vostok, with a series of deep holes at Vostok begun in 1970.^[110] The first deep hole at Vostok reached 506.9 m in April 1970; by 1973 a depth of 952 m had been reached. A subsequent hole, Vostok 2, drilled from 1971 to 1976, reached 450 m, and Vostok 3 reached 2202 m in 1985 after six drilling seasons.^[111] Vostok 3 was the first core to retrieve ice from the previous glacial period, 150,000 years ago.

https://en.wikipedia.org/wiki/Ice_core