Regions: North Slave Region
| Principal Investigator: | McPeak, Sara E (1) |
| Licence Number: | 16346 |
| Organization: | Carleton University |
| Licensed Year(s): |
2018
|
| Issued: | Jun 29, 2018 |
| Project Team: | Sara McPeak, Claire Samson, Barrett Elliott |
Objective(s): To test if passive seismics can be used to map the thickness of overburden in a permafrost-rich environment; and, to compare overburden thickness derived from passive seismic data and known overburden thickness from drilling.
Project Description: The objectives of this project are to test if passive seismics can be used to map the thickness of overburden in a permafrost-rich environment; and, to compare overburden thickness derived from passive seismic data and known overburden thickness from drilling. This project will test to see if the earth’s natural vibration can be used to determine how much sand, gravel, soil and permafrost are at a given location. Taking these measurements involves digging a 5 cm deep hole to place a passive seismic instrument and leaving it to take measurements for around half an hour. These measuring instruments only measure vibrations from the earth. This will be done at around 200 locations in a buried bedrock valley somewhere in the Yellowknife area. The Tromino seismometer will be the instrument used to estimate the overburden thickness. Closely-spaced measurements (~25m station spacing) will be completed along the transects. Several transects will be studied to evaluate the performance of passive seismics in different situations: thin versus thick overburden, permafrost of variable thickness, and overburden of different composition. Measurements will also be taken near boreholes where the depth to bedrock is known, to validate the passive seismic data. This information will be correlated with borehole data and used in forward modelling in order to estimate the shear wave velocity versus depth profile. This work will be done in collaboration with the Northwest Territories Geological Survey. Results of the field work of July 2018 will be presented at the Yellowknife Geoscience Forum in November 2018. The fieldwork for this study will be conducted from July 1, 2018 to July 31, 2018.
