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Geological Development of the Jan Mayen Micro Continent and its Continental Margins
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The Jan Mayen micro continent is isolated from other continental crust central in the North Atlantic. This master thesis is a seismic interpretation study of the northern part of the micro continent, using 2D seismic reflection data. Broadband seismic surveys from 2012 and 2011 are used together with older data in order to get an overview of the geological history of the micro continent, with emphasis on the continental margins.The method of interpretation was initial observation of the seismic lines, then mapping of the important features such as major truncation-surfaces and strong basal reflectors. Finally, the mapped lines were interpreted and linked to geological processes. Five seismic lines that displayed important features were included in the thesis. The general features displayed on these lines were put together and used to create one profile which displays the geological development of the micro continent. The general development of the micro continent is strongly linked to the continental break ups between Greenland and Eurasia in the Early Eocene and between Jan Mayen and East-Greenland in the Early Miocene.The result of the Early Eocene breakup was a volcanic margin on the eastern margin of the Jan Mayen area. Accumulation space in the Jan Mayen area was filled in with sediments from Greenland as Greenland and Norway drifted apart, identified in a pre-breaking sequence. Subsequently, the area became subject to significant extension. Sedimentation continued throughout the extensional phase, which was identified in a syn-rifting sedimentary sequence. Eventually, the sea floor spreading to the east of Jan Mayen died out, and a non-volcanic break on the western margin of the Jan Mayen area separated the micro continent from Greenland, and a post rifting sequence was deposited. It is suggested in this thesis that an increase in melt production post-break-up lead to an extensive distribution of volcanic intrusions throughout the Jan Mayen Basin, as well as the area above the eastern continent-ocean transition. The intruded areas are thought to have been areas of weakness in the crust, making propagation for the intrusion easier.