NEIU students in ESCI 211: Physical Geology set out to answer this question on November 27, 2002.
 

Simulated meteorite impact craters
Bird's eye view of simulated impact craters.  Width of photo 12 in. White powder is flour, and brown powder is cocoa.	Oblique view of simulated impact craters.
Close-up view of impact crater.  The green marble "meteorite" is visible in the bottom of the crater; this is not a very realistic aspect of the simulation.  Large meteorites would be largely vaporized on impact.	Note the raised rim of the crater and the ejecta rays radiating outwards.  Fractures are evident around the rim.

Volcanic craters produced by collapse of magma chamber (balloon deflates).
	Two members of the group "The Faults" record observations of their simulated volcanic collapse crater.  A balloon was attached to one end of the clear plastic hose, inflated, and buried inside a "mountain" of flour.  When air was released from the free end of the hose, the balloon collapsed, simulating collapse of a magma chamber.
	Bird's eye view of collapse crater.  Brown powder is cocoa powder.

 

Hey, what happens if you pop the balloon??
	Group "Hot Spots" joins "Big Bangers" and "Great Granites" to find out what happens when the balloon is popped suddenly. Getting set to bury the balloon.
	Coating the mountain surface with cocoa.
	Getting set to pop the balloon through the bottom of the pan (with a teasing needle).
	Poof!
	Another try at popping the balloon.  Here's the "before" picture.
	Good action shot!
	This is what happens when you pop a really big balloon!
	Group "Blueschist" packs the flour around their balloon...
	...and finds out the "crater" takes the shape of the balloon when you do that!

 
 
 

Examining photos of craters on Earth, Venus, and Mars.
	Group "Hot Spots" examines photographs of craters on Earth, Venus and Mars, using what they observed in the lab simulations to form hypotheses on how the craters in the photos were formed.