Mercury’s Low Reflectance Material — Evidence for Graphite Flotation in a Magma Ocean?

Rachel Klima,Nancy Chabot,Carolyn Ernst,Sebastien Besse,Marc Fries,Kathleen Vander Kaaden

doi:10.3847/25c2cfeb.59bdf057

Abstract

Whitepaper #265 submitted to the Planetary Science and Astrobiology Decadal Survey 2023-2032. Topics: interior evolution and volcanism; Mercury and/or the Moon; solar system formation, dynamics processes, and chronology

Highlights

Mercury was revealed by the MESSENGER mission to be an enigmatic and exciting planet
Elemental measurements confirm an extremely low abundance of iron in Mercury’s crust (Nittler et al, 2011; Evans et al, 2012; Weider et al, 2014), and, based on visible and NIR measurements, the small amount of iron that is detected may be contained in sulfides or even reduced as iron metal
Vander Kaaden et al (2017) used the available elemental data to compute the cation norms for nine geochemical regions, and their results showed that the high reflectance plains (HRP) contain ~58% plagioclase and a mixture of low and high-Ca pyroxene, with almost 8% quartz in Caloris

Summary

Introduction

Mercury was revealed by the MESSENGER mission to be an enigmatic and exciting planet. Elemental measurements confirm an extremely low abundance of iron in Mercury’s crust (Nittler et al, 2011; Evans et al, 2012; Weider et al, 2014), and, based on visible and NIR measurements, the small amount of iron that is detected may be contained in sulfides or even reduced as iron metal.

Results

Conclusion