centre d'expansion des fonds océaniques

CONT: Minéralisation de sulfures hydrothermaux des centres d'expansion des fonds océaniques.
OBS: centre de renouvellement des fonds océaniques : terme en usage à Ressources naturelles Canada - Secteur des sciences de la Terre.
PHR: Centre d'expansion des fonds océaniques actif.

CONT: In 1963, F. Vine and D.H. Matthews reasoned that, as basaltic magma rises to form new ocean floor at a mid-ocean spreading center, it records the polarity of the magnetic field existing at the time magma crystallized. As spreading pulls the new oceanic crust apart, stripes of approximately the same size should be carried away from the ridge on each side ... Basaltic magma forming at mid-ocean ridges serves as a kind of ""tape recorder"", recording the Earth's magnetic field as it reverses through time. If this idea is correct, alternating stripes of normal and reversed polarity should be arranged symmetrically about mid-ocean spreading centers.
CONT: Buoyant flow beneath oceanic spreading centres can be driven by density gradients due to thermal expansion and compositional gradients arising from the extraction of melt.
OBS: oceanic spreading centre: term used at Natural Resources Canada - Earth Sciences Sector.