A study on Dyngjufjoll volcanic centre by Sigvaldason (2002) has investigated the relationship between crustal rebound and glacier melting at the Pleistocene-Holocene boundary. Despite being impossible to attribute geological hazards during that epoch to humans, an understanding on how climate change influences crustal dynamics is essential when looking forward into the anthropocene. In central Iceland, ice thickness amounts to 1,500-2,000 m at peak glaciation. This loading produces a 400-500 m depression on the crust. After a temperature increase and a reduction of ice load via glacial melting, rapid crustal rebound ensued as a result of low mantle viscosity at an average uplift rate of almost half a metre per year.
Tephrachoronological dating has been effective in revealing the high volcanic production rate. For example, a pumice deposit was used as a marker that was found within a sediment horizon, which signifies the Plinian rhyolitic eruption that was dated at roughly 10 ka. At the time of this eruption, volcanic activity was successive and coincides when glaciers retreated from the coastal areas of Iceland. Additionally, rhyolitic pumice was found to be distributed amongst dated tephra layers along the north and east coasts of the country. Ultimately, the likely cause of the Plinian eruption is the pressure release that occurred in response to glacial melting which triggered volatile supersaturation. The Dyngjufjoll is a complex Pleistocene volcanic structure which provides a useful case study of how the process of glacial melt, tectonic movement and crustal rebound resulted in a volcanic productivity of almost 30 times the present rate.
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