elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Dynamical effects of multiple impacts: Large impacts on a Mars-like planet

Ruedas, T. and Breuer, Doris (2019) Dynamical effects of multiple impacts: Large impacts on a Mars-like planet. Physics of the Earth and Planetary Interiors, 287, pp. 76-92. Elsevier. DOI: 10.1016/j.pepi.2019.01.003 ISSN 0031-9201

[img] PDF - Registered users only until March 2021
35MB

Official URL: http://dx.doi.org/10.1016/j.pepi.2019.01.003

Abstract

The earliest stage of the evolution of a fully assembled planet is profoundly affected by a number of basin-forming impacts large enough to change the dynamics of its deeper interior. These impacts are in some cases quite closely spaced and follow one another in short time intervals, so that their effects interact and result in behavior that may differ from a simple sum of the effects of two individual and isolated impacts. We use two-dimensional models of mantle convection in a Mars-like planet and a simple parameterized representation of the principal effects of impacts to study some of the dynamical effects and interactions of multiple large impacts. In models of only two impacts, we confirm that the dynamical effects of the impacts reinforce each other the closer they are in space and time but that the effects do not always correspond to straightforward superpositions of those of single, isolated impacts. In models with multiple (4-8) impacts with variable sizes, distances, and frequencies, the global response of the mantle is as variable as the impact sequences in the short term, but in the long term the different evolutionary paths converge for several indicator variables such as the mean flow velocity, temperature, or heat flow. Nonetheless, beyond a certain impact frequency and energy, lithospheric instabilities triggered by large impacts occur on a global scale, reinvigorate mantle dynamics for long time spans, and entail a late stage of melt production in addition to the initial melting stage that is not observed in one- or two-impact models. After one or several very large impacts, some lithospheric material may founder and sink to the core–mantle boundary, and if enough of it accumulates there, it enhances the heat flux out of the core for several hundred millions of years, with possible effects on dynamo activity.

Item URL in elib:https://elib.dlr.de/126193/
Document Type:Article
Title:Dynamical effects of multiple impacts: Large impacts on a Mars-like planet
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Ruedas, T.thomas.ruedas (at) dlr.dehttps://orcid.org/0000-0002-7739-1412
Breuer, DorisDoris.Breuer (at) dlr.dehttps://orcid.org/0000-0001-9019-5304
Date:February 2019
Journal or Publication Title:Physics of the Earth and Planetary Interiors
Refereed publication:Yes
Open Access:No
Gold Open Access:No
In SCOPUS:Yes
In ISI Web of Science:Yes
Volume:287
DOI :10.1016/j.pepi.2019.01.003
Page Range:pp. 76-92
Publisher:Elsevier
ISSN:0031-9201
Status:Published
Keywords:Mars; mantle convection; impacts
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:Space Science and Exploration
DLR - Research area:Raumfahrt
DLR - Program:R EW - Erforschung des Weltraums
DLR - Research theme (Project):R - Vorhaben Planetary Evolution and Life
Location: Berlin-Adlershof
Institutes and Institutions:Institute of Planetary Research > Planetary Physics
Deposited By: Ruedas Gomez, Thomas
Deposited On:04 Feb 2019 09:49
Last Modified:06 Sep 2019 15:19

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.