22-EPN3-129: In-situ and laboratory spectroscopic characterisation of Icelandic lava flows
January 22, 2024

22-EPN3-129: In-situ and laboratory spectroscopic characterisation of Icelandic lava flows; an analogue of Venus – VERITAS mission preparation

Nils Mueller and Akin Domac (German Aerospace Center (DLR), Germany) to TA1 – Iceland Field Sites, MATIS
Dates of visit: 1-7 August 2023

As part of collaborative field work of the VERITAS science team, Nils Mueller and Akin Domac visited several locations with partially sediment covered lava flows in the vicinity of Askja, Vatnajokull National Park, Iceland. This was done simultaneously with an airborne radar campaign by the German Aerospace Center {DLR. e.V.) acquiring synthetic aperture radar images at X- and S-band, the wavelengths of the radar instruments on the Venus orbiters VERITAS and Magellan, respectively. The objective of the field­work was to document the nature and extend of sediment cover on lava flows and how it affects scattering and roughness at radar wavelengths. This will improve the combined Magellan/VERITAS SAR image interpretation by providing in-situ data that can be tied to specific S and X band backscatter values. Another aspect is change detection as the same airborne radar collected data of the near pristine Holuhraun lava flow in 2015.

The field work data collected includes photos, notes, LIDAR scans of SxS m2 patches, and clast and sediment samples from the the surface and, if possible, from 20 cm depth. The initial observations show that parts of the Holuhraun lava flow have been significantly modified by aeolian sediments in the 8 years since the end of the eruption. These sediments affect the roughness on radar wavelengths but also radar backscatter via changes in composition, density, clast size, and water content. Whether the changes are notable in the radar images remains to be seen, as the interpretation is ongoing.

Photos from the campaign can be found in the DLR Flickr Album: VERITAS – Expedition for NASA & ESA Missions to Venus: