Planetary Geology pdf - NASA

10. Based on your three sketches of the sugar cone, diagram the effect the cone has on the wind movement. Do this
by imagining you can see the wind. Draw arrows to show how you think the wind moves around the cone.
Part Two
Clean up all the sugar on the table. Form another 5 cm high cone of sugar in the spot of greatest wind movement.
Place obstacles (keys, small rocks, eraser, etc.) at different locations on the table downwind of the cone of
sugar. Place the obstacles at different orientations to the wind. For example, with a long side parallel, perpendicular
or at an angle to the wind; flat or on its side. Turn on the fan at the same speed as in part one. After three minutes
turn the fan off and observe the deposition and erosion of sugar around the obstacles.
11. Make a sketch (include both a top and side view) of each obstacle and the sugar surrounding it. Add arrows
to indicate the movement of the wind around each obstacle. (use Sketch Area B).
Sketch Area B
12. Where does most of the deposition occur at the obstacle? Where does most of the erosion occur?
Part Three
Remove the obstacles and clean up all the sugar on the table. Form a thin (few grains thick) layer of sugar
20 cm by 20 cm in size and make a 3 cm high cone of sugar in the center. Make sure the cone is in the spot of
maximum wind. Use the ball to form a bowl-shaped crater on the pile. Remove the ball and make an initial
sketch of the crater. Include a top and side view.
13. Initial Sketch (use Sketch Area C):
In this part of the activity, you will be turning the fan on and off for three one-minute intervals to monitor
the progress of erosion of the crater. Turn on the fan at the same speed used previously, producing
moderate movement of the sugar. After one minute, turn off the fan and observe what changes have
occurred to the crater and the surrounding area. Sketch what you observed. Include a top and side view,
as well as arrows indicating the wind movement over and around the crater.
14. a. Sketch after first one-minute interval (use Sketch Area C):
b. Sketch after second one-minute interval (use Sketch Area C):
c. Sketch after final one-minute interval (use Sketch Area C):
15. How is the movement of the wind around the crater different from the movement of the wind around
the cone in Part One?
Exercise Nine: Aeolian Processes
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EG-1998-03-109-HQ Activities in Planetary Geology for the Physical and Earth Sciences