The impact of variability in the rheological activation parameters onlower-mantle viscosity stratification and its dynamics

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F11%3A10105458" target="_blank" >RIV/00216208:11320/11:10105458 - isvavai.cz</a>

Výsledek na webu

—

DOI - Digital Object Identifier

—

Jazyk výsledku

angličtina

Název v původním jazyce

The impact of variability in the rheological activation parameters onlower-mantle viscosity stratification and its dynamics

Popis výsledku v původním jazyce

The recently discovered spin-state crossover in iron in major mantleminerals at high pressures should exert dramatic influences on transport properties, such as the activation creep parameters in the deep mantle. Wentzcovitch et al. (2009) have computedthe elastic parameter of ferropericlase that is affected by this crossover, the bulk modulus, at high realistic conditions, using first principles density functional theory plus Hubbard U. As a consequence of the spin crossover there is a significant softening of the bulk modulus and an attendant reduction of the activation energy in the creep law. Using a parameterized model capturing the basic physics, we have studied the dynamical consequences within the framework of a 2-D Cartesian convection model.Our models reveal a series of asthenospheres and are characterized first by a low-viscosity channel below the 670 km boundary (''second asthenosphere'') caused by an increase of temperature and decrease in grain size reduction (superplas

Název v anglickém jazyce

The impact of variability in the rheological activation parameters onlower-mantle viscosity stratification and its dynamics

Popis výsledku anglicky

The recently discovered spin-state crossover in iron in major mantleminerals at high pressures should exert dramatic influences on transport properties, such as the activation creep parameters in the deep mantle. Wentzcovitch et al. (2009) have computedthe elastic parameter of ferropericlase that is affected by this crossover, the bulk modulus, at high realistic conditions, using first principles density functional theory plus Hubbard U. As a consequence of the spin crossover there is a significant softening of the bulk modulus and an attendant reduction of the activation energy in the creep law. Using a parameterized model capturing the basic physics, we have studied the dynamical consequences within the framework of a 2-D Cartesian convection model.Our models reveal a series of asthenospheres and are characterized first by a low-viscosity channel below the 670 km boundary (''second asthenosphere'') caused by an increase of temperature and decrease in grain size reduction (superplas

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

DE - Zemský magnetismus, geodesie, geografie

OECD FORD obor

—

Projekt

<a href="/cs/project/GAP210%2F11%2F1366" target="_blank" >GAP210/11/1366: Materiálové vlastnosti a dynamika spodního pláště Země</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2011

Kód důvěrnosti údajů

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

Název periodika

Physics of the Earth and Planetary Interiors

ISSN

0031-9201

e-ISSN

—

Svazek periodika

188

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

8

Strana od-do

1-8

Kód UT WoS článku

000297086400001

EID výsledku v databázi Scopus

—