Toggle Main Menu Toggle Search

Open Access padlockePrints

The physical and chemical composition of the lower mantle

Lookup NU author(s): Dr Isabella Bovolo

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Abstract

This article reviews some of the recent advances made within the field of mineral physics. In order to link the observed seismic and density structures of the lower mantle with a particular mineral composition, knowledge of the thermodynamic properties of the candidate materials is required. Determining which compositional model best matches the observed data is difficult because of the wide variety of possible mineral structures and compositions. State-of-the-art experimental and analytical techniques have pushed forward our knowledge of mineral physics, yet certain properties, such as the elastic properties of lower mantle minerals at high pressures and temperatures, are difficult to determine experimentally and remain elusive. Fortunately, computational techniques are now sufficiently advanced to enable the prediction of these properties in a self-consistent manner, but more results are required. A fundamental question is whether or not the upper and lower mantles are mixing. Traditional models that involve chemically separate upper and lower mantles cannot yet be ruled out despite recent conflicting seismological evidence showing that subducting slabs penetrate deep into the lower mantle and that chemically distinct layers are, therefore, unlikely. Recent seismic tomography studies giving three-dimensional models of the seismic wave velocities in the Earth also base their interpretations on the thermodynamic properties of minerals. These studies reveal heterogeneous velocity and density anomalies in the lower mantle, which are difficult to reconcile with mineral physics data.


Publication metadata

Author(s): Bovolo CI

Publication type: Article

Publication status: Published

Journal: Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences

Year: 2005

Volume: 363

Issue: 1837

Pages: 2811-2835

ISSN (print): 1364-5021

ISSN (electronic): 1471-2946

Publisher: The Royal Society Publishing

URL: http://dx.doi.org/10.1098/rsta.2005.1675

DOI: 10.1098/rsta.2005.1675


Altmetrics

Altmetrics provided by Altmetric


Share