THE MEDUSAE FOSSAE FORMATION, MARS: SEARCHING FOR THE FORMER EXTENT OF A PUTATIVE VOLCANICALLY AEOLIAN DEPOSIT

The Medusae Fossae Formation (MFF) is an unconformable deposit that covers approximately 2.1x10⁶ km² over the equatorial region of Mars. MFF ranges in thickness from tens to thousands of meters without a definitive source. Based on previous work, common characteristics of MFF include aeolion landforms such as: yardangs, herringbone textures, and pedestal craters. Hypotheses of its origin include, but are not limited to, massive singular volcanic eruptions (with various assumptions of magma composition) and global climate-altering events caused by changes in Mars’ obliquity. By examining the surface adjacent to the currently mapped MFF, we seek evidence to determine whether the MFF once covered a larger area, and if so, how much larger, and at what time in the past. Constraining a more accurate areal extent of the present and past MFF deposit will improve our understanding of how the MFF was emplaced, and the rate at which it has eroded.

We created 4 transects (3 in a N-S orientation, 1 in an E-W orientation) all of which surround presently mapped boundaries of the MFF. Each transect consists of 1° x 1° boxes; the transects are 3° wide and sufficiently long to extend past the previously mapped MFF outcrops. Each 1° box is examined for previously unrecognized outcrops of MFF. We used the Java Mission-planning and Analysis for Remote Sensing (JMARS) and relied most heavily on Context Camera (CTX; ~5 m/px resolution) images to investigate each of the boxes. Preliminary results suggest that these areas contain previously unidentified outcrops of MFF that represent a larger expanse of the formation than is currently mapped.