Plume Activity and Tidal Deformation on Enceladus Influenced by Faults and Variable Ice Shell Thickness

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F17%3A10367151" target="_blank" >RIV/00216208:11320/17:10367151 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1089/ast.2016.1629" target="_blank" >http://dx.doi.org/10.1089/ast.2016.1629</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1089/ast.2016.1629" target="_blank" >10.1089/ast.2016.1629</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Plume Activity and Tidal Deformation on Enceladus Influenced by Faults and Variable Ice Shell Thickness

Popis výsledku v původním jazyce

We investigated the effect of variations in ice shell thickness and of the tiger stripe fractures crossing Enceladus&apos; south polar terrain on the moon&apos;s tidal deformation by performing finite element calculations in three-dimensional geometry. The combination of thinning in the polar region and the presence of faults has a synergistic effect that leads to an increase of both the displacement and stress in the south polar terrain by an order of magnitude compared to that of the traditional model with a uniform shell thickness and without faults. Assuming a simplified conductive heat transfer and neglecting the heat sources below the ice shell, we computed the global heat budget of the ice shell. For the inelastic properties of the shell described by a Maxwell viscoelastic model, we show that unrealistically low average viscosity of the order of 1013 Pa s is necessary for preserving the volume of the ocean, suggesting the important role of the heat sources in the deep interior. Similarly, low viscosity is required to predict the observed delay of the plume activity, which hints at other delaying mechanisms than just the viscoelasticity of the ice shell. The presence of faults results in large spatial and temporal heterogeneity of geysering activity compared to the traditional models without faults. Our model contributes to understanding the physical mechanisms that control the fault activity, and it provides potentially useful information for future missions that will sample the plume for evidence of life. KeyWords: Enceladus-Tidal deformation-Faults-Variable ice shell thickness-Tidal heating- Plume activity and timing. Astrobiology 17, 941-954.

Název v anglickém jazyce

Plume Activity and Tidal Deformation on Enceladus Influenced by Faults and Variable Ice Shell Thickness

Popis výsledku anglicky

We investigated the effect of variations in ice shell thickness and of the tiger stripe fractures crossing Enceladus&apos; south polar terrain on the moon&apos;s tidal deformation by performing finite element calculations in three-dimensional geometry. The combination of thinning in the polar region and the presence of faults has a synergistic effect that leads to an increase of both the displacement and stress in the south polar terrain by an order of magnitude compared to that of the traditional model with a uniform shell thickness and without faults. Assuming a simplified conductive heat transfer and neglecting the heat sources below the ice shell, we computed the global heat budget of the ice shell. For the inelastic properties of the shell described by a Maxwell viscoelastic model, we show that unrealistically low average viscosity of the order of 1013 Pa s is necessary for preserving the volume of the ocean, suggesting the important role of the heat sources in the deep interior. Similarly, low viscosity is required to predict the observed delay of the plume activity, which hints at other delaying mechanisms than just the viscoelasticity of the ice shell. The presence of faults results in large spatial and temporal heterogeneity of geysering activity compared to the traditional models without faults. Our model contributes to understanding the physical mechanisms that control the fault activity, and it provides potentially useful information for future missions that will sample the plume for evidence of life. KeyWords: Enceladus-Tidal deformation-Faults-Variable ice shell thickness-Tidal heating- Plume activity and timing. Astrobiology 17, 941-954.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10500 - Earth and related environmental sciences

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Astrobiology

ISSN

1531-1074

e-ISSN

—

Svazek periodika

17

Číslo periodika v rámci svazku

9

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

14

Strana od-do

941-954

Kód UT WoS článku

000410801300011

EID výsledku v databázi Scopus

—