Airborne geophysical surveys

Survey name	Type	Altitude	Spacing	Flight line distance
Burlington	M/R-D	121.92 m	9.66 km	2,742 km
Southern Iowa	M-A	609.6 m (barometer)	1.61 km	8,546 km
North Missouri Ground Mag	M-Dz	Ground m at ground level	1.61 km	km