Shock-darkening in ordinary chondrites: Determination of the pressure-temperature conditions by shock physics mesoscale modeling

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985831%3A_____%2F17%3A00481577" target="_blank" >RIV/67985831:_____/17:00481577 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1111/maps.12935" target="_blank" >http://dx.doi.org/10.1111/maps.12935</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1111/maps.12935" target="_blank" >10.1111/maps.12935</a>

Result language

angličtina

Original language name

Shock-darkening in ordinary chondrites: Determination of the pressure-temperature conditions by shock physics mesoscale modeling

Original language description

We determined the shock-darkening pressure range in ordinary chondrites using the iSALE shock physics code. We simulated planar shock waves on a mesoscale in a sample layer at different nominal pressures. Iron and troilite grains were resolved in a porous olivine matrix in the sample layer. We used equations of state (Tillotson EoS and ANEOS) and basic strength and thermal properties to describe the material phases. We used Lagrangian tracers to record the peak shock pressures in each material unit. The post-shock temperatures (and the fractions of the tracers experiencing temperatures above the melting point) for each material were estimated after the passage of the shock wave and after the reflections of the shock at grain boundaries in the heterogeneous materials. The results showed that shock-darkening, associated with troilite melt and the onset of olivine melt, happened between 40 and 50 GPa with 52 GPa being the pressure at which all tracers in the troilite material reach the melting point. We demonstrate the difficulties of shock heating in iron and also the importance of porosity. Material impedances, grain shapes, and the porosity models available in the iSALE code are discussed. We also discuss possible not-shock-related triggers for iron melt.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Meteoritics & Planetary Science

ISSN

1086-9379

e-ISSN

—

Volume of the periodical

52

Issue of the periodical within the volume

11

Country of publishing house

US - UNITED STATES

Number of pages

16

Pages from-to

2375-2390

UT code for WoS article

000414860200006

EID of the result in the Scopus database

2-s2.0-85033241577