Equations of state of the high-pressure phases of a natural peridotite and implications for the Earth's lower mantle

Mathematics – Logic

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

17

Peridotite, Pyrolite, Orthorhombic Perovskite, Magnesiowüstite, Calcium Perovskite, High Pressure, X-Ray Diffraction, Lower Mantle

Scientific paper

To help determine the chemical composition of the Earth's mantle, we characterised the high-pressure mineral assemblage of an undepleted natural peridotite-thought to be representative of the Earth's upper-mantle-to 107 GPa using high-resolution X-ray diffraction. At lower-mantle conditions, the peridotite transforms to the assemblage 76 (+/-2)% (Mg0.88Fe0.052+Fe0.013+Al0.12Si0.94)O3 orthorhombic perovskite by volume (at zero pressure), 17 (+/-2)% (Mg0.80Fe0.20)O magnesiowüstite and 7 (+/-1)% CaSiO3 perovskite. The measured room-temperature bulk properties of this high-pressure assemblage, together with a range of estimates of thermal properties of the constituent minerals, appear to be inconsistent with seismological constraints on the density and bulk modulus of the lower mantle. Our results suggest that the lower mantle differs in bulk composition (e.g., richer in iron, Mg#~0.85) from current estimates for the upper mantle, requiring some amount of segregation between the upper and lower mantle over geological history.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Equations of state of the high-pressure phases of a natural peridotite and implications for the Earth's 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 Equations of state of the high-pressure phases of a natural peridotite and implications for the Earth's lower mantle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Equations of state of the high-pressure phases of a natural peridotite and implications for the Earth's lower mantle will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1009205

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.