Date of Award

2019

Document Type

Open Access Master's Thesis

Degree Name

Master of Science in Geophysics (MS)

Administrative Home Department

Department of Geological and Mining Engineering and Sciences

Advisor 1

Aleksey Smirnov

Committee Member 1

Chad Deering

Committee Member 2

Jeremy Shannon

Abstract

The magnetic properties of the ~1.88 Ga Vulcan Iron Formation and Felch Formation were investigated from samples taken from three drill cores through the Felch Trough, north of Iron Mountain, MI. The conducted analyses included measurements of natural remanent magnetization, magnetic hysteresis, first order reversal curves, magnetic anisotropy, scanning electron microscopy, and electron dispersive spectroscopy. The data is compared to the results of a previous magnetic characterization study conducted on surface outcrop samples on two members of the Vulcan formation, the Curry and Traders members, near Iron Mountain, MI. Two distinct members of the Vulcan Formation were identified in the core samples that correlated to the members from the surface samples. While there were some similarities between the surface and core samples, the core samples presented higher magnetic susceptibilities by 1-2 orders of magnitude as well as a lower ratio of hematite to magnetite than the surface samples. The discrepancy may be due to the oxidation of magnetite to hematite by surface weathering. The obtained results, particularly the higher magnetic susceptibility, will be useful for interpretation of data collected by an aeromagnetic survey conducted in the area by the USGS.

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