Aerodynamic and vorticity erosion of Mars: Part I. The formation of channels

Abstract

Wind-erosion processes may include much more than generally realized. Besides abrasion caused by sand-grain impact and saltation, there are several other processes that can be classed as aerodynamic. Three of the most important are vorticity, inter-facial flow, and aerodynamic lift. Using suspended particles as the tools of erosion, the first two of these modes of erosion account for the development of pits, pit chains, and ultimately linear erosion trends. Aerodynamic lift, which occurs in both negative flow and vorticity, is a means of rendering materials airborne in response to differential pressure at extremely low velocity and without need for saltation. Aerodynamic processes provide system to erosion. Hence, shapes of features in most cases define the flow patterns which produced them. This paper is designed to demonstrate how to utilize clues that show aerodynamic influence in the shaping of features, how to make assessments of regional flow systems as related to major topographic features, and how to use the data of aerodynamic and vorticity erosion in assessing the origins of certain features on Mars.