Analyzing Compositional, Mineralogical, and Petrological Variations in Syrtis Major Planum Lava Flows Throughout Martian Time

The volcanic record of Mars is of great importance because of what it can indicate about the development of the planet and how it compares to Earth. However, compositions of most major martian volcanic regions are difficult to study with thermal infrared (TIR) spectroscopy given that dust covering the lava flows serves to mask spectral signatures. Syrtis Major Planum is a low-relief shield volcano with a minimal dust content and represents the best example of a Surface Type 1 dominated volcanic region. While no longer volcanically active, the lava flows that were generated from Syrtis can serve as a reflection of the processes that were occurring in its magmatic source. This study aims to identify compositional, mineralogical, and petrological variations between temporally and spatially distinct flows to determine the extent of any differentiation throughout the volcanic record of Syrtis. Thermal Emission Spectrometer (TES) data was utilized from various lava flows as mapped in Demchuk (2021). Spectral endmembers were input into a linear deconvolution algorithm and used to model TES spectra. Modeled endmember percentages are interpreted to be representative of mineral modes. These were used to derive rock types and bulk chemistries. Preliminary deconvolution results are consistent with previous studies that have identified mafic igneous rocks dominated by high Ca-pyroxene and plagioclase feldspar. Extensive comparisons of different-aged lava flows are being made in an effort to track variations across martian geologic time. A lack of compositional, mineralogical, and/or petrological variation would indicate limited or nonexistent magmatic evolution and would raise the question of what processes would lead to this lack of differentiation. Alternatively, evidence for significant variations of overall or individual attributes between flows may represent magmatic evolution in Syrtis Major and could imply large-scale changes to martian volcanism during the Noachian – Hesperian transition.