mineral physics

 

  • The most common tool is a diamond anvil cell, which uses diamonds to put a small sample under pressure that can approach the conditions in the Earth’s interior.

  • It was known that the average density of the Earth was about twice that of the crust, but it was not known whether this was due to compression or changes in composition in
    the interior.

  • [citation needed] Properties of materials Equations of state[edit] To deduce the properties of minerals in the deep Earth, it is necessary to know how their density varies
    with pressure and temperature.

  • First, temperatures below 1200 °C are difficult to measure using this method.

  • [9]: 107–109  History The field of mineral physics was not named until the 1960s, but its origins date back at least to the early 20th century and the recognition that the
    outer core is fluid because seismic work by Oldham and Gutenberg showed that it did not allow shear waves to propagate.

  • Creating high temperatures Achieving temperatures found within the interior of the earth is just as important to the study of mineral physics as creating high pressures.

  • Several methods are used to reach these temperatures and measure them.

  • A very useful heuristic was discovered by Francis Birch: plotting data for a large number of rocks, he found a linear relation of the compressional wave velocity of rocks
    and minerals of a constant average atomic weight with density :[10][11] .

  • Creating high pressures Shock compression[edit] Many of the pioneering studies in mineral physics involved explosions or projectiles that subject a sample to a shock.

  • Laboratory work in mineral physics require high pressure measurements.

  • Pressures as high as any in the Earth have been achieved by this method.

  • The concentration of pressure at the tip of the diamonds is possible because of their hardness, while their transparency and high thermal conductivity allow a variety of probes
    can be used to examine the state of the sample.

  • Laser heating is continuing to extend the temperature range that can be reached in diamond-anvil cell but suffers two significant drawbacks.

  • Second, large temperature gradients exist in the sample because only the portion of sample hit by the laser is heated.

  • The apparatus is very bulky and cannot achieve pressures like those in the diamond anvil cell (below), but it can handle much larger samples that can be quenched and examined
    after the experiment.

  • First principles calculations[edit] Main article: Prediction of crystal properties by numerical simulation Using quantum mechanical numerical techniques, it is possible to
    achieve very accurate predictions of crystal’s properties including structure, thermodynamic stability, elastic properties and transport properties.

  • The latter is one of many Grünheisen parameters that play an important role in high-pressure physics.

  • The conditions of the experiment must be interpreted in terms of a set of pressure-density curves called Hugoniot curves.

  • Williamson and Adams assumed that deeper rock is compressed adiabatically (without releasing heat) and derived the Adams–Williamson equation, which determines the density
    profile from measured densities and elastic properties of rocks.

 

Works Cited

[‘Ahrens, T. J. (1980). “Dynamic compression of Earth materials”. Science. 207 (4435): 1035–1041. doi:10.1126/science.207.4435.1035. PMID 17759812. S2CID 21791428.
^ Kawai, Naoto (1970). “The generation of ultrahigh hydrostatic pressures by a split sphere
apparatus”. Review of Scientific Instruments. 41 (8): 1178–1181. doi:10.1063/1.1684753.
^ Kubo, Atsushi; Akaogi, Masaki (2000). “Post-garnet transitions in the system Mg4Si4O12–Mg3Al2Si3O12 up to 28 GPa: phase relations of garnet, ilmenite and perovskite”.
Physics of the Earth and Planetary Interiors. 121 (1–2): 85–102. doi:10.1016/S0031-9201(00)00162-X.
^ Zhang, Jianzhong; Liebermann, Robert C.; Gasparik, Tibor; Herzberg, Claude T.; Fei, Yingwei (1993). “Melting and subsolidus relations of silica
at 9 to 14 GPa”. Journal of Geophysical Research. 98 (B11): 19785–19793. doi:10.1029/93JB02218.
^ “Studying the Earth’s formation: The multi-anvil press at work”. Lawrence Livermore National Laboratory. Archived from the original on 28 May 2010.
Retrieved 29 September 2010.
^ Zhai, Shuangmeng; Ito, Eiji (2011). “Recent advances of high-pressure generation in a multianvil apparatus using sintered diamond anvils”. Geoscience Frontiers. 2 (1): 101–106. doi:10.1016/j.gsf.2010.09.005.
^ Hemley,
Russell J.; Ashcroft, Neil W. (1998). “The Revealing Role of Pressure in the Condensed Matter Sciences”. Physics Today. 51 (8): 26. doi:10.1063/1.882374.
^ Yan, J., Doran, A., MacDowell, A.A. and Kalkan, B., 2021. A tungsten external heater for BX90
diamond anvil cells with a range up to 1700 K. Review of Scientific Instruments, 92(1), p.013903.
^ Jump up to:a b Poirier 2000
^ Birch, F. (1961). “The velocity of compressional waves in rocks to 10 kilobars. Part 2”. Journal of Geophysical Research.
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^ Birch, F. (1961). “Composition of the Earth’s mantle”. Geophysical Journal of the Royal Astronomical Society. 4: 295–311. doi:10.1111/j.1365-246X.1961.tb06821.x.
^ Burnley, Pamela. “Synchrotron
X-Ray Diffraction”. Science Education Resource Center. Carleton College. Retrieved 18 September 2015.
^ Jump up to:a b Thomas, Sylvia-Monique. “Infrared and Raman Spectroscopy”. Science Education Resource Center. Carleton College. Retrieved 18 September
2015.
^ Thomas, Sylvia-Monique. “Brillouin Spectroscopy”. Science Education Resource Center. Carleton College. Retrieved 18 September 2015.
^ Burnley, Pamela. “Ultrasonic Measurements”. Science Education Resource Center. Carleton College. Retrieved
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^ Price, G. David (October 2007). “2.01 Overview – Mineral physics: past, present, and future” (PDF). In Price, G. David (ed.). Mineral Physics. Elsevier. pp. 1–6. ISBN 9780444535764. Retrieved 27 September 2017.
^ Jump up to:a
b c Hemley, Russell J. (April 2006). “Erskine Williamson, extreme conditions, and the birth of mineral physics”. Physics Today. 59 (4): 50–56. doi:10.1063/1.2207038.
^ Prewitt, Charles T. (2003). “Mineral Physics: Looking ahead”. Journal of Mineralogical
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^ Liebermann, Robert Cooper; Prewitt, Charles T. (March 2014). “From Airlie House in 1977 to Granlibakken in 2012: 35Years of evolution of mineral physics”. Physics of the Earth and Planetary
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