Grand Rapids (MI)

Survey type M/R-D (magnetic; radiometric; collected in digital form)
Flown by EG&G
Line spacing 9.66 (km)
Altitude 121.92 (m)
Total distance 3,310 (km)
Counties Cook - Lake - Allegan - Barry - Berrien - Branch - Calhoun - Cass - Clinton - Eaton - Hillsdale - Ingham - Ionia - Jackson - Kalamazoo - Kent - Lenawee - Livingston - Ottawa - Saint Joseph - Shiawassee - Van Buren - Washtenaw - Kenosha - Milwaukee - Racine
Overlapping surveys

Data: Magnetic, radiometric (NURE) (NURE)