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Drainage, topographic, and gravity anomalies in the Lake Superior Region: Evidence for a 1100 Ma mantle plume
Author(s) -
Allen David J.,
Hinze William J.,
Can William F.
Publication year - 1992
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/92gl02285
Subject(s) - geology , lithosphere , mantle plume , gravity anomaly , plume , rift , mantle (geology) , crust , underplating , geophysics , dome (geology) , tectonics , transition zone , geodynamics , geomorphology , seismology , paleontology , physics , oil field , thermodynamics
A topographic dome, radial drainage pattern, and regional negative gravity anomaly, all centered on Lake Superior, are vestiges of a 1100 Ma mantle plume that formed the Midcontinent Rift System of central North America. The topographic and gravimetric relations suggest that the dome is maintained isostatically by fundamental changes imprinted on the lithosphere by the plume, including magmatic underplating of the crust and depletion of the upper mantle. These changes occurred at distances of up to 500 km or more from the center of the plume, well beyond the margins of the rift.