TY  - JOUR
A1  - Reitze, Maximilian P.
A1  - Weber, Iris
A1  - Morlok, Andreas
A1  - Hiesinger, Harald
A1  - Pasckert, Jan Hendrik
A1  - Schmedemann, Nico
A1  - Bauch, Karin E.
A1  - Stojic, Aleksandra N.
A1  - Helbert, Jörn
T1  - Mid‐Infrared Spectroscopy of Feldspars From the Bühl Basalt (Northern Hesse, Germany) Formed Under Reducing Conditions as Terrestrial Analogue of Mercury for MERTIS
Y1  - 2023-05-24
VL  - 10
IS  - 6
SP  - 
EP  - 
JF  - Earth and Space Science
DO  - 10.1029/2023EA002903
PB  - 
N2  - <title xmlns:mml="http://www.w3.org/1998/Math/MathML">Abstract</title><p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en">The MErcury Radiometer and Thermal Infrared Spectrometer instrument onboard the BepiColombo spacecraft is designed to investigate Mercury’s surface in the mid‐infrared (mid‐IR). Based on MESSENGER data and modeling, Mercury is thought to be evolved under highly reducing conditions (e.g., McCubbin et al., 2017, <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.1002/2017JE005367">https://doi.org/10.1002/2017JE005367</ext-link>; Namur &amp; Charlier, 2017, <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.1038/ngeo2860">https://doi.org/10.1038/ngeo2860</ext-link>). The modeling also indicates that Mercury's surface is rich in feldspar. However, it is unknown if reducing conditions during the emplacement of volcanic melts have an influence on the IR properties of feldspars. Therefore, we investigated basaltic samples from the Bühl quarry in northern Hesse, Germany, that evolved under reducing conditions in the mid‐IR and compared the spectra with samples that experienced more oxidizing conditions during their formation. The Bühl samples are feldspar‐rich and contain metallic iron in some areas. Our investigations show that there are no differences between feldspars that formed under different oxidizing conditions. All spectral properties could be explained by well‐known factors that affect mid‐IR spectra of silicates.</p>
N2  - Plain Language Summary: ESA's and Japan Aerospace Exploration Agency’s spacecraft BepiColombo is equipped, beside other instruments, with a thermal infrared (IR) radiometer and spectrometer called MErcury Radiometer and Thermal Infrared Spectrometer (MERTIS). For the accurate interpretation of the data from the MERTIS instrument, laboratory analog material is necessary. This analog material must fulfill different characteristics, such as different chemical and mineralogical compositions. Another not yet studied property is the availability of oxygen during the formation of the minerals. Depending on how much oxygen is available, different minerals form. However, this is an important feature, because Mercury is thought to have evolved under highly reducing conditions, as opposed to Earth where nearly all material formed significant more oxidizing conditions. One phase that is strongly associated with reducing magma formation conditions is metallic iron. There are only few natural outcrops on Earth, were stronger reducing conditions were present so that metallic iron could be formed. One of these outcrops is the Bühl quarry in northern Hesse, Germany. From there we used different samples to analyze the effect of oxygen availability on mid‐IR spectra of plagioclase feldspars.</p>
N2  - Key Points: <list list-type="bullet"> <list-item> <p xml:lang="en">We present infrared spectra of basaltic samples from the Bühl, Hesse, Germany in preparation of the MERTIS experiment</p></list-item> <list-item> <p xml:lang="en">Comparison of feldspars formed at different oxygen fugacities showed no spectral differences</p></list-item> <list-item> <p xml:lang="en">This is an important result for MERTIS, which will investigate Mercury that formed under reducing conditions</p></list-item> </list> </p>
UR  - http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/11317
ER  -