Mercury's crust likely made of magnesium-rich basalt

Jan 29, 2013
Mercury. Credit: NASA

With both x-ray and gamma-ray spectrometers, the MErcury Surface, Space ENvironment, GEochemistry and Ranging probe (MESSENGER), which entered orbit around Mercury in 2011, is well equipped for carrying out a detailed compositional analysis of Mercury's crust, the understanding of which could help determine the nature of the planet's formation, and of its volcanic past.

Using spectrometric measurements and of Mercury surface-analogue samples, Stockstill-Cahill et al. determine that the upper layers of Mercury's crust most closely resemble magnesian basalt , though with lower iron concentrations. To make their determination, the authors used a software package known as MELTS to simulate the cooling and crystallization of potential Mercurian lavas with different chemical compositions, estimating the temperatures at which minerals would crystallize out of the and the abundances of different mineral species. Similarly, the authors simulated the cooling of magnesium-rich terrestrial rocks and of meteoritic samples.

Based on their chemical compositional analysis, the authors infer a number of properties for an early lava on Mercury. They suggest that the lava would have had a very low viscosity, streaming across the surface in widespread but thin layers. Further, they calculate that the temperatures required to produce the magnesium-rich lava would have been much higher than for terrestrial rocks not enriched in magnesium.

The authors say that the low-viscosity lava would leave tell-tale marks on the planet's surface that could be identified through further MESSENGER observations.

Explore further: Two Galileo satellites lose their way

More information: Magnesium-rich crustal compositions on Mercury: Implications for magmatism from petrologic modeling, Journal of Geophysical Research-Planets, doi: 10.1029/2012JE004140, 2012 http://onlinelibrary.wiley.com/doi/10.1029/2012JE004140/abstract

add to favorites email to friend print save as pdf

Related Stories

Characterizing the surface composition of Mercury

Sep 17, 2012

The MESSENGER spacecraft, which has been orbiting Mercury since March 2011, has been revealing new information about the surface chemistry and geological history of the innermost planet in the solar system. ...

Mercury's magnetic field measured by MESSENGER orbiter

May 15, 2012

Researchers working with NASA's Mercury Surface, Space Environment, Geochemistry, and Ranging (MESSENGER) spacecraft report the frequent detections of Kelvin-Helmholtz (KH) waves at the edge of the innermost ...

Recommended for you

Two Galileo satellites lose their way

3 hours ago

Two European Galileo satellites launched as part of a navigation system designed to rival GPS have failed to locate their intended orbit, launch firm Arianespace said Saturday.

SpaceX rocket explodes during test flight

12 hours ago

A SpaceX rocket exploded in midair during a test flight, though no one was injured, as the company seeks to develop a spacecraft that can return to Earth and be used again.

Amazing raw Cassini images from this week

Aug 22, 2014

When Saturn is at its closest to Earth, it's three-quarters of a billion miles away—or more than a billion kilometers! That makes these raw images from the ringed planet all the more remarkable.

Europe launches two navigation satellites

Aug 22, 2014

Two satellites for Europe's rival to GPS were lifted into space on Friday to boost the Galileo constellation to six orbiters of a final 30, the European Space Agency (ESA) said.

SpaceX gets 10-year tax exemption for Texas site

Aug 22, 2014

Cameron County commissioners have agreed to waive 10 years of county taxes as part of an agreement bringing the world's first commercial site for orbital rocket launches to the southernmost tip of Texas.

User comments : 0