Premium
Effect of water on olivine‐wadsleyite phase boundary in the (Mg, Fe) 2 SiO 4 system
Author(s) -
Chen Jiuhua,
Inoue Toru,
Yurimoto H.,
Weidner Donald J.
Publication year - 2002
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 - 10.1029/2001gl014429
Subject(s) - olivine , discontinuity (linguistics) , geology , phase boundary , mantle (geology) , mineralogy , classification of discontinuities , phase (matter) , geophysics , chemistry , mathematics , organic chemistry , mathematical analysis
The phase boundary between San Carlos olivine and its high pressure phase, wadsleyite, have been studied comparatively in dry and water saturated condition. By comparing saturated and dry samples from the same experimental run, we determine that both boundaries of the two‐phase coexisting loop shift towards lower pressure or lower iron content, and the pressure width of the loop decreases to 0.3 GPa under saturated conditions at 1473 K. Thus, the presence of water in the Earth's mantle will sharpen the 410‐kilometer seismic discontinuity, shallow the depth of the discontinuity, and reduce the velocity jump across the discontinuity.