Open AccessPropagating rift model for the V‐shaped ridges south of Iceland
Author(s) -
Hey Richard,
Martinez Fernando,
Höskuldsson Ármann,
Benediktsdóttir Ásdís
Publication year - 2010
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1029/2009gc002865
Subject(s) - geology , seafloor spreading , rift , ridge , fault scarp , mid ocean ridge , rift valley , plume , rift zone , seismology , transform fault , geophysics , paleontology , tectonics , physics , thermodynamics
We present new marine geophysical data which constrain the seafloor spreading history of the Reykjanes Ridge near Iceland and the origin of its flanking V‐shaped topographic and gravity ridges. Contrary to the geometry assumed in pulsing plume models, the V‐shaped ridges are not symmetric about the Reykjanes Ridge axis, and seafloor spreading has not been symmetric about a stable axis. Thus, existing models must at least be modified to include an additional asymmetry‐producing mechanism; the best understood and documented such mechanism is rift propagation. One possibility is that plume pulses drive the propagators. However, rift propagation also produces V‐shaped wakes with crustal thickness variations, suggesting the possibility that a pulsing Iceland plume might not be necessary to explain the Reykjanes V‐shaped ridges, scarps, and troughs.