Interpretations of geoid anomalies around the Iceland hotspot

• Published in: Geophysical Journal International
• Main Author: Marquart, G.
• Format: Text
• Language: English
• Published: Oxford University Press 1991
• Subjects: Articles; Greenland; Iceland; North Atlantic
• Online Access: http://gji.oxfordjournals.org/cgi/content/short/106/1/149; https://doi.org/10.1111/j.1365-246X.1991.tb04608.x

Geoid height anomalies around the Iceland hotspot in an area extending between 50°W to 14°E and 45°N to 72°N have been investigated to search for evidence of an upper mantle thermal anomaly. After removing wavelengths longer than 3800 km, the effect of the cooling lithosphere was eliminated by low-pass filtering of age data and applying the boundary model. The effects of the various platforms and swells in the North Atlantic were removed by an Airy model, since the geoid-to-topography ratio is lower than 1.5 m km-1 for all areas of elevated topography independent of their origin. The residual geoid shows a large positive anomaly with a steep constant slope towards a location (north)west of Iceland beneath Greenland. The amplitude of the anomaly can be estimated to at least 8 m. The geoid-to-topography ratio reaches a value of 7 m km-1 which is in good agreement with a plume-related anomaly.