Evaluating an impact origin for Mercury's high-magnesium region

Elizabeth A. Frank, Ross W.K. Potter, Oleg Abramov, Peter B. James, Rachel L. Klima, S. Mojzsis, Larry R. Nittler

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

During its four years in orbit around Mercury, the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft's X-ray Spectrometer revealed a large geochemical terrane in the northern hemisphere that hosts the highest Mg/Si, S/Si, Ca/Si, and Fe/Si and lowest Al/Si ratios on the planet. Correlations with low topography, thin crust, and a sharp northern topographic boundary led to the proposal that this high-Mg region is the remnant of an ancient, highly degraded impact basin. Here we use a numerical modeling approach to explore the feasibility of this hypothesis and evaluate the results against multiple mission-wide data sets and resulting maps from MESSENGER. We find that an ~3000 km diameter impact basin easily exhumes Mg-rich mantle material but that the amount of subsequent modification required to hide basin structure is incompatible with the strength of the geochemical anomaly, which is also present in maps of Gamma Ray and Neutron Spectrometer data. Consequently, the high-Mg region is more likely to be the product of high-temperature volcanism sourced from a chemically heterogeneous mantle than the remains of a large impact event.

Original languageEnglish
Pages (from-to)614-632
Number of pages19
JournalJournal of Geophysical Research: Planets
Volume122
Issue number3
DOIs
Publication statusPublished - Mar 1 2017

Fingerprint

Geochemistry
Mercury
mercury
Mercury surface
Magnesium
magnesium
aerospace environments
geochemistry
Neutron spectrometers
Gamma ray spectrometers
basins
spectrometers
X ray spectrometers
Earth mantle
Planets
spectrometer
basin
Topography
mantle
Spacecraft

Keywords

  • geochemistry
  • impact
  • Mercury
  • MESSENGER

ASJC Scopus subject areas

  • Geophysics
  • Oceanography
  • Forestry
  • Aquatic Science
  • Ecology
  • Condensed Matter Physics
  • Water Science and Technology
  • Soil Science
  • Geochemistry and Petrology
  • Earth-Surface Processes
  • Physical and Theoretical Chemistry
  • Polymers and Plastics
  • Atmospheric Science
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science
  • Materials Chemistry
  • Palaeontology

Cite this

Frank, E. A., Potter, R. W. K., Abramov, O., James, P. B., Klima, R. L., Mojzsis, S., & Nittler, L. R. (2017). Evaluating an impact origin for Mercury's high-magnesium region. Journal of Geophysical Research: Planets, 122(3), 614-632. https://doi.org/10.1002/2016JE005244

Evaluating an impact origin for Mercury's high-magnesium region. / Frank, Elizabeth A.; Potter, Ross W.K.; Abramov, Oleg; James, Peter B.; Klima, Rachel L.; Mojzsis, S.; Nittler, Larry R.

In: Journal of Geophysical Research: Planets, Vol. 122, No. 3, 01.03.2017, p. 614-632.

Research output: Contribution to journalArticle

Frank, EA, Potter, RWK, Abramov, O, James, PB, Klima, RL, Mojzsis, S & Nittler, LR 2017, 'Evaluating an impact origin for Mercury's high-magnesium region', Journal of Geophysical Research: Planets, vol. 122, no. 3, pp. 614-632. https://doi.org/10.1002/2016JE005244
Frank, Elizabeth A. ; Potter, Ross W.K. ; Abramov, Oleg ; James, Peter B. ; Klima, Rachel L. ; Mojzsis, S. ; Nittler, Larry R. / Evaluating an impact origin for Mercury's high-magnesium region. In: Journal of Geophysical Research: Planets. 2017 ; Vol. 122, No. 3. pp. 614-632.
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