NWT RESEARCH DATABASE

Regions: Sahtu Settlement Area

Tags: physical sciences, geochemistry, rock, pegmatites, mineralization

Objective(s): To constrain the connection between the niobium-yttrium-fluorine and lithium-cesium-tantalum pegmatites and assess the parental connections to the granite batholith which will provide insight into the evolution of melt over time and to analyze the age of mineralization which will help place these pegmatites in a temporal context with regional events

Project Description: This licence has been issued for the scientific research application No.5299. The main objectives of this fieldwork are to: 1) constrain the connection between the Niobium-Yttrium-Fluorine (NYF) and Lithium-Cesium-Tantalum (LCT) pegmatites; 2) assess the parental connections to the granite batholith which will provide insight into the evolution of melt over time, leading to a deeper understanding of the O’Grady rocks and of pegmatites in general; 3) analyze the age of mineralization which will help place these pegmatites in a temporal context with regional events; and 4) map their extent which will reveal information on why they are found in their modern day location. Drawing these research questions, this project aims to constrain the age, extent, and geochemical origins of the NYF and LCT mixed pegmatite suite at the O’Grady batholith. During the proposed 12-day visit to the O’Grady batholith we will assess the extent of pegmatite mineralization while collecting a representative sample set to ensure that high-quality analyses can be obtained. Field-based detailed mapping will reveal the extent and different types of minerals within the pegmatite field and will allow detailed notes to be taken regarding pegmatite evolution. It is unusual to gain lithium enrichment within pegmatites of hornblende granitic origins; therefore, post fieldwork geochemical analysis (including X-ray diffraction, scanning electron microscope, and electron microprobe analysis) of minerals and microscope analyses will provide insight into the origins and evolution of melt in the region. The use of age dating (geochronological) techniques, such as zircon, apatite and columbite group mineral dating, will reveal an accurate age of mineralization from which the evolution of the pegmatite can be assessed. After completing analyses and interpretation, the research team will write a paper based on the results and submit it to a peer-reviewed international scientific journal (for example The Canadian Mineralogist). The team will also present the findings at the NWT Geoscience Conference. If possible the team would like to engage the Sahtu indigenous community (the ancestral inhabitants of the region in which our research will be based) by presenting the finding in a community lecture in order to inform an audience which has been an underrepresented group in science. The fieldwork for this study will be conducted from July 26, 2022 to August 08, 2022