NWT RESEARCH DATABASE

Regions: North Slave Region

Tags: geology, petrology, Structural geology, #structuralgeology #mapping, paleomagnetism

Objective(s): The team proposes to target the areas near Bell Lake and between Dwyer/Homer Lakes. The objective would be to carry out high resolution (10s -100s of metre scale) geological mapping of igneous intrusions and folds and localized strain/alteration to identify the best possible targets for paleomagnetic research. Oriented samples will be collected from across igneous intrusions, or around folds, in order to verify whether records of magnetization pre-date these geological events.

Project Description: This licence has been issued for the scientific research application No. 5997. The team proposes to target the areas near Bell Lake and between Dwyer/Homer Lakes, since these are well-studied, with high resolution geological maps already published in the literature and new U-Pb ages have recently been acquired for many of the rocks here, which will be key for interpreting the age of magnetization in collected samples. The objective would be to carry out high resolution (10s -100s of metre scale) geological mapping of igneous intrusions and folds and localized strain/alteration to identify the best possible targets for paleomagnetic research. Once these targets have been identified, the team will collect oriented samples from across igneous intrusions, or around folds, in order to verify whether records of magnetization pre-date these geological events. Geological mapping would be carried out using iPads to survey the area. No samples will be taken during this part of the project, only observational data, such as rock-type and structural measurements. The team will carry out 2 - 3 days of geological mapping, aiming to cover an area between 6 - 10 km^2 at each site. This mapping will allow us to identify specific areas that are promising for paleomagnetic research (well-dated, low degree of metamorphism/local deformation). The team would then spend 1-2 days collecting oriented samples either as block samples taken with a sledge hammer, or using a rock-coring drill (https://www.ascscientific.com/products/pomeroy-ez-core-d261-c-drill) to sample 2.5-cm diameter cores with a depth of 10 - 15 cm. The team would aim to collect 20 - 30 samples per site (approx 15 - 25 kg of material) and would aim to target a maximum of 3 or 4 sites around Bell Lake and Dwyer/Homer Lakes. The team appreciates that drilling must be done with the upmost care, and would strive to not drill obvious faces of outcrop, and to hammer out or fill in drill holes where possible. If drilling is not deemed permissible then sampling will be undertaken as block sampling only, although this will impact the quality of our results as sampling resolution will be lower. The team will spend time in Yellowknife at the beginning and end of our trip and would welcome advice on the best way to engage with the Yellowknife Dene First Nation. Members of this community will be employed to act as bear monitors during our fieldwork, and could offer outreach talks, Q&A sessions with the community, and one-on-one or small group meetings to explain our research, or provide a more general overview on our geological research to audiences ranging from school children to adults. The PI has been in touch with Bobby Drygeese at B Dene Adventures and Peter Crookedhand at Ek' edia Services to discuss employment as bear monitors, as well as having written to the Yellowknives Dene First Nation via their contact form on their website to explain the purpose of my fieldwork and to ask if a meeting/outreach activities would be of interest to them. A response has yet to be received. The fieldwork for this study will be conducted from: September 01 - September 16, 2024