Aeolian features and processes at the Mars Pathfinder landing site

The Mars Pathfinder landing site contains abundant features attributed to a eolian, or wind, processes. These include wind tails, drift deposits, dunef orms of various types, ripplelike features, and ventifacts (the first clear ly seen on Mars). Many of these features are consistant with formation invo lving sand-size particles. Although some features, such as dunes, could dev elop from saltating sand-size aggregates of finer grains, the discovery of ventifact flutes cut in rocks strongly suggests that at least some of the g rains are crystalline, rather than aggregates. Excluding the ventifacts, th e orientations of the wind-related features correlate well with the orienta tions of bright wind steaks seen on Viking Orbiter images in the general ar ea. They also correlate with wind direction predictions from the NASA-Ames General Circulation Model (GCM) which show that the strongest winds in the area occur in the northern hemisphere winter and are directed toward 209 de grees.