Densities of fertile and sterile garnet peridotites
- 1 September 1976
- journal article
- Published by American Geophysical Union (AGU) in Geophysical Research Letters
- Vol. 3 (9) , 509-512
- https://doi.org/10.1029/gl003i009p00509
Abstract
Densities of a fertile peridotite (PHN 1611) and a depleted sterile peridotite (PHN 1569) have been calculated to be 3.39 and 3.30, respectively. These densities were calculated from the cell dimensions of the component minerals, the mineral analyses, and the bulk rock analyses. Studies of kimberlite nodules suggest that lighter, sterile peridotites overlie heavier, more fertile peridotites uniformly in the upper mantle beneath southern Africa. A temperature difference of 500°C reduces the density of fertile peridotite PHN 1569 to approximately 3.33, which is insufficient to cause it to float in sterile peridotite. However, if fertile peridotite PHN 1569 undergoes 25% partial melting and the garnet is dissolved, its zero pressure density would be reduced to approximately 3.2, which is less than that of depleted, sterile mantle.This publication has 7 references indexed in Scilit:
- Is there an Icelandic mantle plume?Nature, 1975
- Origins of the ultramafic nodules from some kimberlites of northern Lesotho and the Monastery Mine, South AfricaPhysics and Chemistry of the Earth, 1975
- Linear island chains in the Pacific: Result of thermal plumes or gravitational anchors?Journal of Geophysical Research, 1973
- A pyroxene geothermGeochimica et Cosmochimica Acta, 1973
- Estimating Proportions in Petrographic Mixing Equations by Least-Squares ApproximationScience, 1969
- SECTION 6: THERMAL EXPANSIONPublished by Geological Society of America ,1966
- SECTION 4: DENSITY OF ROCKSPublished by Geological Society of America ,1966