Vinsamlegast notið þetta auðkenni þegar þið vitnið til verksins eða tengið í það: http://hdl.handle.net/1946/17125
Lava flows are a common product in various volcanoes on Earth, and are a product of non-explosive extrusions. Modelling of their properties and potential emplacement is important in many locations around the world, given the proximity of inhabited and agricultural areas to active volcanoes. Even if the area around Hekla is sparsely populated, Hekla is one of the most active volcanic systems in Iceland and is well known for its mixed eruptions. Hekla has erupted about 23 times since the settlement of Iceland. Lavas have been produced in at least 22 out of the 23 eruptions. In the past, some of these lavas have affected farms in the area.
In this thesis we use new topographic data to obtain improved estimates of lava flow thicknesses around Hekla Volcano. Thickness is one of the parameters important for recalculation of flow volumes and potential assessment of hazards around Hekla and other similar volcanoes. We calculate the thicknesses along the margins of the flows using a high-resolution Digital Elevation Model based on new radar data. Additionally, we compiled a map of the recent historical lavas at Hekla based on previous lava maps, recent aerial images, and the new radar data.
We tested the method on the 1980-1981 lava and we obtained an area of 23,04 km2, which is consistent with previous studies. Our volume estimate of 0,07 km3 is significantly lower that previous estimates. Finally, we used this method to calculate the area and volume for the 1878 and 1913 lavas. Our volume estimates are 0,03 km3 and 0,02 km3 respectively.
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