Current Research in EEPS: Dr. Marisa Palucis, Dartmouth College
How much water does it take to build a fan on a cold and wet Mars?
Alluvial fans may represent one of the last widespread signs of significant fluvial activity on Mars’ surface. Understanding the climatic conditions during the formation of these features may provide key insights on habitability and climate change on Mars.
Numerous studies have used data and theory from terrestrial fans from warm, arid, rainfall-dominated climates to estimate flow discharges, runoff rates, and total water volumes that likely built Martian fans. However, it has been suggested that Martian fans sourced water only from snowmelt, and perhaps under periglacial conditions. Thus, there is a knowledge gap about the dominant processes building fans under periglacial conditions, and importantly for Mars, a lack of understanding about the characteristic flow magnitudes during depositional events.
In this talk I will present results from a field-based terrestrial analog study involving characterization of the sedimentology and geomorphology of a periglacial alluvial fan in the Richardson Mountains, Northwest Territories, Canada. I will (1) qualitatively describe the range of sedimentary processes occurring on a periglacial alluvial fan and compare them to prior observations, (2) report measured flow discharges and runoff rates that occurred during a summer storm event, and (3) show that melt rates suggested for Mars are capable of entraining and transporting appreciable amounts of sediment by fluvial processes.