The Institute for Rock Magnetism (IRM) is a National Science Foundation Multiuser Facility housed at the University of Minnesota, serving the national and international geoscience community. The IRM’s main purpose is to advance research into the physics and chemistry of the magnetization in natural materials that result from geologic, biologic, and anthropogenic processes. It has five specific objectives:

(1) Maintaining the integrity, function, and accuracy of a suite of state-of-the-art instruments for measuring the magnetic properties of geological, biological, and synthetic materials over a wide range of temperatures (3-1000 K) and magnetic fields (0-7 Tesla), as well imaging magnetic minerals, and investigating magnetic mineral composition through Mössbauer spectroscopy. Over the course of the grant period significant investments were made in the facility and new equipment.

(2) Providing visiting researchers with access, support, and training in the use of IRM instruments, primarily through a competitive Visiting Fellowship program. An external Review and Advisory Committee, comprising an international panel of scientists, evaluates Fellowship proposals and 15-20 Fellowships are awarded annually, with Fellows ranging from undergraduate students through to senior faculty. In addition, 30-40 visitors from local colleges, within the University of Minnesota, and internationally benefit from the facility annually.

(3) Integrating education, training, and research through undergraduate senior thesis, graduate, and postdoctoral research projects, and a biennial Summer School in Rock Magnetism (instituted in 2011). The Summer School is primarily aimed at graduate students and combines lectures that teach the fundamentals of fine-particle magnetism with practical laboratory projects using facility instrumentation.

(4) Organizing the biennial IRM conference, which fosters interdisciplinary cooperation, nationally and internationally, on current and emerging problems in magnetism in the geosciences.

(5) Collecting and disseminating scientific results to the research community and the public through the IRM Quarterly newsletter and the IRM web site.

Rock magnetism has numerous applications across the geosciences, as natural materials invariably contain at least trace amounts of magnetic iron-bearing minerals or alloys. There are two foundational premises of the subject:

(1) Magnetic minerals can record and retain magnetic field information over billions of years; they have magnetic memory analogous to modern magnetic recording media. When igneous rocks cool, sediments settle, sedimentary rocks form, archaeological materials are fired, and extraterrestrial rocks form, they can record the ambient magnetic field at that time, which allows for an understanding of the evolution of Earth, including the dating of rocks and sediments, the past movements of Earth’s tectonic plates, and processes within Earth’s deep interior and other planetary bodies.

(2) The physical and chemical properties of fine magnetic particle populations serve as indicators of past processes or conditions that have affected the rocks, sediments, or soil in which they occur. These reveal information about past environmental and climatic conditions, which can often relate to major events in Earth’s history, and geological processes such as magma emplacement, sediment deposition and transport, rock deformation, faulting and the structural evolution of geological terrains. Nanometer scale magnetic particles are also found in atmospheric dust and urban environments and magnetic methods are used to assess pollution and other anthropogenic activities.

Over the duration of this grant, 188 peer-reviewed papers and five theses have been published by IRM staff, faculty, students, Visiting Fellows, and other visitors that have used data collected and/or analyzed at the IRM to research the above topics, as well as applications in physics, chemistry, material sciences, mechanical and electrical engineering, and health studies.

Last Modified: 07/24/2023
Modified by: Maxwell C Brown