Publikationsdatum:
1998-07-31
Beschreibung:
Simultaneous sound velocity measurements and x-ray diffraction studies were made on wadsleyite (beta-Mg2SiO4) to 7 gigapascals and 873 kelvin. The calculated adiabatic bulk (K) and shear (G) moduli yield K (at room conditions) = 172(2) gigapascals, dK/dP = 4.2(1), and dK/dT = -0.012(1) gigapascals per kelvin, and G (at room conditions) = 113(1) gigapascals, dG/dP = 1.5(1), and dG/dT = -0. 017(1) gigapascals per kelvin, respectively. The data imply that the P and S wave velocity contrasts between olivine and wadsleyite require an olivine amount of 38 to 39 percent in the upper mantle to satisfy the observed 410-kilometer discontinuity, but 55 to 60 percent to account for the velocity increase through the transition zone.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Li -- Liebermann -- Weidner -- New York, N.Y. -- Science. 1998 Jul 31;281(5377):675-7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉B. Li, Center for High Pressure Research and Mineral Physics Institute, State University of New York, Stony Brook, NY 11794-2100, USA. R. C. Liebermann and D. J. Weidner, Center for High Pressure Research and Department of Geosciences, State.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/9685255" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Digitale ISSN:
1095-9203
Thema:
Biologie
,
Chemie und Pharmazie
,
Informatik
,
Medizin
,
Allgemeine Naturwissenschaft
,
Physik
