Habitat caves
	Mammoth cave. Limestone capped by sandstone. Extremly stable. 390 miles of passages. Saltpeter used for fertilizer
		Kentucky Cave Shrimp
		Eastern small-footed, Indiana, gray, little brown, big brown, estern popistrelle bats. 9-12 million
		2 crickets
		Cave salamander
		2 cave fish
		crayfish
		outside: oak-hickry upland forest. beech-maple-tulip poplar in moist areas. Sycamore, silver poplar, river maple, box elder along rivers.
		
		water level controlled by external Green river.
		Nearby fisher ridge cave system (117 miles long) and i
		Martin ridge cave system (34 m long) (conneted to Mammoth by underwater systemi but may not be passable)
		

	Black Hills
		Jewel cave: late find wind. Entrance had to be enlarged.
		Wind cave: late find wind. No minerals.

	Guadalupe mtns
		lechuguilla cave (Carlsbad). guano. 90ft entrance pit, 400 ft passages then rubble
		carlsbad caverns: Natural entrance. limestone.

	Mt. St. Helens
		Ape cave. Lava tube 2mi.
	
	Mesa verde
	Canyon de chelly
	Niagara Cave, MN
	luray caverns
	
	Missouri has 6,000 caves
		Meramec caverns

	Granite caves (fomed by bolders being dropped over cliff by glaciers)
		Polar Cave, NH
	
Mines
	Copper mines on lake superior
	turquoise: mt. chalchihuitl, mexico
	oil pits; titusville, pa
	gold, silver andes of peru, bolivia, chile, argentina