CaltechAUTHORS
  A Caltech Library Service

Post-shock temperatures in minerals

Raikes, Susan A. and Ahrens, Thomas J. (1979) Post-shock temperatures in minerals. Geophysical Journal of the Royal Astronomical Society, 58 (3). pp. 717-747. ISSN 0016-8009. http://resolver.caltech.edu/CaltechAUTHORS:20141111-152226628

[img]
Preview
PDF - Published Version
See Usage Policy.

1721Kb

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20141111-152226628

Abstract

An experimental technique has been developed for the measurement of post-shock temperatures in a wide variety of materials, including those of geophysical interest such as silicates. The technique uses an infrared radiation detector to determine the brightness temperature of samples shocked to pressures in the range 5 to ∼ 30 GPa; in these experiments measurements have been made in two wavelength ranges (4.5 to 5.75 μm; 7 to 14 μm). Reproducible results, with the temperatures in the two wavelength bands generally in excellent agreement, have been obtained for aluminium-2024 (10.5 to 33 GPa; 125 to 260°C), stainless steel-304 (11.5 to 50 GPa; 80 to 350°C), crystalline quartz (5.0 to 21.5 GPa; 80 to 250°C), forsterite (7.5 to 28.0 GPa; ∼ 30 to 160°C) and Bamble bronzite (6.0 to 26.0 GPa; ∼ 30 to 225°C). These results are generally much higher at low pressures (where they may even be in excess of the calculated shock temperatures) than the values calculated assuming a hydrodynamic rheology and isentropic release parallel to the Hugoniot but tend towards them at higher pressures. In aluminium-2024, the theoretical post-shock temperatures, assuming a fluid-like rheology, are 35 to 218°C, for the pressure range 10.5 to 33 GPa. However, the results are in considerably better agreement with values calculated assuming elasto-plastic behaviour (80 to 270°C) which probably also causes the high measured temperatures for stainless steel. In forsterite the measured values ranged from 65°C at 9.6 GPa (there was no detectable rise at 7.5 GPa) to 156° at 28.0 GPa, whereas the ‘hydrodynamic values’ were 30 to 120°C. Values obtained for quartz were in excellent agreement with those calculated by Mashimo et al. using release adiabat data. It is concluded that release adiabat data should be used, wherever available, for calculations of residual temperature, and that adequate descriptions of the shock and release processes in minerals need to be more complex than generally assumed.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1111/j.1365-246X.1979.tb04804.xDOIArticle
http://gji.oxfordjournals.org/content/58/3/717.abstractPublisherArticle
Additional Information:Copyright © 1979 The Royal Astronomical Society. Received 1979 February 5; in original form 1978 September 12. The authors thank Raymond Jeanloz and Gregory Lyzenga for many interesting and stimulating discussions; they are also indebted to Wayne Miller and Victor Nenow, who designed and built the variable gain amplifier used with the InSb detector, and to the staff of the Santa Barbara Research Centre, Goleta, California for their advice concerning detector operation. We thank D. Stöffler for both his comments on impact metamorphism, and the final version of the manuscript. This work was supported by NASA under grant NGL 05-002-105. Contribution No. 3143, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA.
Funders:
Funding AgencyGrant Number
NASANGL 05-002-105
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Caltech Division of Geological and Planetary Sciences3143
Record Number:CaltechAUTHORS:20141111-152226628
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20141111-152226628
Official Citation:Susan A. Raikes and Thomas J. Ahrens Post-shock temperatures in minerals Geophys. J. Int. (1979) 58 (3): 717-747 doi:10.1111/j.1365-246X.1979.tb04804.x
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:51607
Collection:CaltechAUTHORS
Deposited By: George Porter
Deposited On:11 Nov 2014 23:35
Last Modified:13 Feb 2019 18:06

Repository Staff Only: item control page