2003 Rock Properties Database: Density, Magnetic Susceptibility, and Natural Remanent Magnetization of Rocks in Minnesota

Abstract

Geologic interpretation of gravity and magnetic anomaly data in a given area is greatly enhanced if density, magnetic susceptibility and natural remanent magnetization (NRM) data are available for representative rock-types. Along with outcrop and drill-hole information, rock property data help relate geophysical anomaly signatures to probable rock types, and provide constraints on the use of anomaly data as a tool for mapping and for modeling geology at depth.

Most of the density and magnetization data contained in this database were acquired over the last two decades by the Minnesota Geological Survey (MGS) as part of an on-going program to collect rock properties. A group of Paleozoic samples were collected from Iowa and included in the database because they provide a representative suite of data for rocks present, but not widely exposed in Minnesota. Additional data were derived from studies by the U. S. Geological Survey (Bath, 1962; Beck, 1970; Beck and Lindsley, 1969; Books, 1972; Jahren, 1965), The University of Minnesota (Bleifuss, 1952, Mooney and Bleifuss, 1952), The University of Western Ontario (Palmer, 1970), and the Geological Survey of Canada (Dubois, 1962).