Physics
Scientific paper
Aug 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006pepi..157..139p&link_type=abstract
Physics of the Earth and Planetary Interiors, Volume 157, Issue 1-2, p. 139-149.
Physics
13
Scientific paper
Phase relations in natural mid-oceanic ridge basalt (MORB) were investigated to depths of 700 1400 km in the lower mantle, using a laser-heated diamond-anvil cell and synchrotron X-ray diffraction (XRD). The crystalline phases, their unit-cell volumes and proportions were determined from Rietveld refinement of the in situ XRD spectra. At the top of the lower mantle, Mg-rich perovskite is the most abundant phase, followed by Ca-rich perovskite and stishovite. Two Al-rich phases occur in smaller amounts, the Ca-ferrite type and the new aluminum-rich phase (or NAL). This assemblage is stable down to 1150 km, approximately. At greater depths, the new aluminum-rich phase disappears, and the assemblage of Mg-rich perovskite, Ca-rich perovskite, stishovite and Ca-ferrite phase is stable up to at least 1400 km. In view of the present phase diagram, we discuss the nature and relations of the lower mantle Al-phases in MORB composition, and their bearing on the density evolution of the oceanic crust.
Cardon Hervé
Daniel Isabelle
Fiquet Guillaume
Guignot Nicolas
Mezouar Mohamed
No associations
LandOfFree
Phase transformations of subducted basaltic crust in the upmost lower mantle does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Phase transformations of subducted basaltic crust in the upmost lower mantle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phase transformations of subducted basaltic crust in the upmost lower mantle will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1105048