Geologic Mapping of Ascraeus Mons, Mars

Abstract:

Ascraeus Mons is one of the three large shield volcanoes in the Tharsis Montes province on Mars. We are conducting geologic mapping of Ascraeus in ArcMap 10.3 at 1:1,000,000 scale using a CTX dataset as a primary basemap. The CTX dataset is supplemented by HRSC, HiRISE, THEMIS, and MOLA data. Our objective is to determine the areal extent, distribution, and age relationships of different lava flow morphologies on the main flank, rift apron, and associated small-vent field of Ascraeus Mons to: (1) identify and understand changes in effusive style across the volcano, and (2) provide insight into martian magma production rates. Our mapping, thus far, at a CTX resolution (~6 m/pixel) shows a variety of effusive styles on the flanks, rift aprons, and plains on and around Ascraeus Mons. Our plan to address (1) is to create a geologic map of Ascraeus Mons. We will use this map to determine where and how different lava flows were emplaced on the flanks and surrounding plains of Ascraeus Mons. We will determine relative ages of units using the emplacement of different geological units, impacts, tectonics, and erosion via superposition relations. We will relate eruptive styles by comparing how different flows are oriented around Ascraeus Mons. Our plan for (2) is to use CTX, MOLA and HRSC datasets to determine volumes of the emplaced lava flows. The volumes will be used to calculate yield strengths and viscosities of each flow. The yield strengths and viscosities will be used to calculate magma production rates. These will prove important to better understand the history and creation of Ascraeus Mons and other volcanoes on other planetary bodies.