Analysis of Palaeogene strike-slip tectonics along the southern East Greenland margin (Sødalen area)

• Published in: Geological Survey of Denmark and Greenland (GEUS) Bulletin
• Main Author: Guarnieri, Pierpaolo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Geological Survey of Denmark and Greenland (GEUS) 2011
• Subjects: Greenland; Sødalen; East Greenland
• Online Access: https://geusbulletin.org/index.php/geusb/article/view/4868; https://doi.org/10.34194/geusb.v23.4868

This paper describes structural data collected during field work in southern East Greenland, a region characterised by a complex tectonic history. Here, 3D photogeology based on aerial and oblique photographs using high-resolution photogrammetry of a 150 km2 area in Sødalen in southern East Greenland shows ESE–WNW-trending faults cross-cutting Paleocene rift structures and flexure-related normal faults. The kinematic analysis highlights oblique and left-lateral strike-slip movements along faults oriented 120°. Strike-slip and dip-slip kinematic indicators on the walls of the chilled contacts between alkaline E–W-oriented dykes and the volcanic host rocks suggest that the faults and dykes formed at the same time, or maybe the faults were re-activated at a later stage. Palaeostress analysis, performed by inversion of fault-slip data, shows the presence of three different tectonic events. Coupling the 3D photogeological tool with structural analysis at key localities is a fundamental way to understand better the tectonic history of such a large area.