The Application of Geophysical Inversion Techniques to the Nechalacho Rare Earth Element Deposit, NT

• Main Author: Kouhi, Derek W.
• Format: Text
• Language: English
• Published: Scholarship@Western 2016
• Subjects: Inverse theory; joint inversion; geophysical modelling; Nechalacho; Thor Lake; Blatchford Lake Intrusion Complex; Geology; Geophysics and Seismology; Blatchford Lake; Canada; Yellowknife
• Online Access: https://ir.lib.uwo.ca/etd/4164; https://ir.lib.uwo.ca/context/etd/article/5847/viewcontent/auto_convert.pdf

The Nechalacho deposit is a world-class rare earth element deposit located in the Thor Lake region approximately 100 kilometers southwest of Yellowknife, NT, Canada. Located within the Blatchford Lake Intrusion Complex, this deposit has the potential to be a large-scale economic asset due to its relatively shallow and sub-horizontal geometry. In this study, geophysical inversion techniques are used to model subsurface magnetic susceptibility and density in order to delineate the deposit. Isolated and joint inversion of both magnetic and gravity data provides similar models. Each inversion procedure delineates a shallow, sub-horizontal layer of high susceptibility and density in approximately the same location. This layer is interpreted to be the Nechalacho deposit and extends further north than previously determined. Finally, magnetic susceptibilities were measured on select samples using laboratory instruments to quality check previous field measurements as well as validate and derive relationships between geophysical and mineralogical properties in the deposit.