Glaciovolcanism in the Tharsis volcanic province of Mars: Implications for regional geology and hydrology

The Tharsis region of Mars is a vast volcanic plateau which hosts the immense Tharsis Montes shield volcanoes. The Tharsis region is suggested by multiple lines of morphologic and modeling evidence to have been a site of coincident volcanic and glacial activity throughout the majority of the geologic history of Mars. The prolonged and overlapping histories of volcanism and glaciation within the Tharsis region raise the likelihood of widespread surficial glaciovolcanism, a possibility which is supported by the recognition of glaciovolcanic landforms in the region by past investigations. Given this likelihood, we perform an exploratory study to assess the potential role that surficial glaciovolcanism may have played in the geologic and hydrologic history of the Tharsis region. We first review the history and characteristics of volcanism and glaciation in the Tharsis region, as well as previously documented evidence for past glaciovolcanic activity, in order to outline relevant conditions and parameters. The outlined volcanic and glacial conditions are then used in conjunction with results and predictions from past modeling of surficial glaciovolcanic processes to assess the potential role of glaciovolcanism in the formation of the Tharsis region's major tectonic and hydrologic features. We conclude that surficial glaciovolcanism may plausibly have contributed to the formation of many of the tectonic and fluvial features in the Tharsis region, offering advantages over prior formation models, particularly for the large basin/chaos-sourced outflow channels concentrated in the area. The formation of a range of investigated features in the Tharsis region by surficial glaciovolcanism does not require ambient warm and wet climate conditions therefore suggesting potential consistency between the observed features and a predominantly cold and icy climate. Consequently, this analysis represents an incremental contribution to better understanding the climatic and hydrologic evolution of Mars. However, analyses performed in this work indicate that the glaciovolcanic origin models we considered are unable to viably account for the complete range of explored features, indicating that future work is required to better resolve the processes involved in their formation.