RIS4E at Kilauea’s December 1974 (D1974) Flow: In Situ Geochemical Analysis and Laboratory Spectral Characterization of Fumarolic Alteration.

Abstract:

The December 1974 (D1974) flow in the SW rift zone at Kilauea Volcano, Hawaii, has been established as a Mars analog due to its physical and chemical properties as well as its interaction with the outgassing plume from the primary Kilauea caldera. The RIS4E (Remote, In Situ and Synchrotron Studies for Science and Exploration) node of the SSERVI (Solar System Exploration Research Virtual Institute) program has conducted two field campaigns to the D1974 flow in an effort to study both its morphology and emplacement history as well as its geochemical and mineralogical signature. Several field portable instruments were deployed at the field site, including handheld x-ray fluorescence, field portable x-ray diffraction, a multispectral imager, Light Detection and Ranging, Ground Penetrating Radar, and a kite capable of producing high-resolution images and Digital Terrain Model data products.

This study specifically focuses on the combination of field data with laboratory infrared spectra acquired in the MIR and VNIR ranges. We focus on the solfatara site which consists of hydrothermally-altered basalt deposited in and around an actively degassing volcanic vent situated directly adjacent to the D1974 flow on its NW side. Preliminary laboratory results indicate that the samples exhibit IR signatures consistent with various sulfates (K, Ca, Mg, Na, Al, Fe⁺³, Cu, Zn, Sr), clay minerals, amorphous silica, Fe-oxides, and/or sulfur. This data will give us a rich understanding of the solfatara site and enable us to make inferences about the hydrothermal alteration products formed in similar Martian environments.