Title | Mapping the Eastern Denali and Tintina faults for geothermal energy exploration |
| |
Author | Finley, T; Salomon, G; Nissen, E; Stephen, R; Cassidy, J F ; Menounos, B |
Source | American Geophysical Union Geophysical Monograph 2022, 1 pages |
Links | Online - En ligne
|
Image |  |
Year | 2022 |
Alt Series | Natural Resources Canada, Contribution Series 20220254 |
Publisher | American Geophysical Union |
Meeting | AGU Fall Meeting; Chicago; US; December 12-16, 2022 |
Document | serial |
Lang. | English |
Media | paper; digital; on-line |
File format | pdf |
Province | Yukon |
NTS | 115G/06; 105A/02 |
Area | Burwash Landing; Watson Lake |
Lat/Long WENS | -139.5000 -139.0000 61.5000 61.2500 |
Lat/Long WENS | -128.5000 -128.5000 60.2500 60.0000 |
Subjects | tectonics; energy resources; energy; faults; mapping techniques; seismic risk; seismology; Denali Fault; Tintina Fault; Geothermal energy |
Program | Public Safety Geoscience Assessing Earthquake Geohazards |
Released | 2022 12 13 |
Abstract | The communities of Burwash Landing and Watson Lake in the Yukon seek geothermal energy resources to improve energy and food security. These two communities are respectively situated adjacent to the
Eastern Denali fault (EDF) and Tintina fault (TF); both faults are theorized to act as conduits for geothermal water to the near surface. The modern strain rate, kinematics, and geometry of faults are key controls on permeability and are thus highly
relevant to geothermal exploration. The EDF is known to have hosted at least four > M6 earthquakes in the past 6800 years, but a lack of high-resolution imagery or lidar coverage has hindered understanding of its kinematics and prevented detailed
mapping of its trace. No paleoseismic studies have been conducted on the TF, although a slip rate of 0.5 mm/yr has been estimated from geodetic measurements. Here, we present new mapping of segments of these faults using lidar datasets collected with
a rotary-wing drone and crewed fixed-wing aircrafts. Along the EDF, we map 70 km of the Holocene surface rupture in detail and identify segments that would be more likely to be permeable (i.e., zones of localized extension). We also improve
constraints on kinematics and earthquake recurrence; stream-channels and risers are observed to be dextrally offset between 5-75 m, with greater offsets on older geomorphological surfaces, implying that cumulative offset from multiple ruptures can be
distinguished. Along the inferred trace of the TF near Watson Lake, the lidar reveals a previously unmapped fault scarp dextrally offsetting an early Holocene glaciofluvial outwash channel; this is the first modern surface rupture ever to be
identified along the TF. Notably, the scarp is spatially coincident with a small outcrop (< 0.1 km3) of Pleistocene (~200-600 ka) basalt flow, which may indicate a localized zone of extension along the fault. Our results will help guide decisions
about geothermal drilling and exploration along the EDF and TF, and also highlight the need to consider seismic hazard along these fault zones. |
Summary | (Plain Language Summary, not published) In this study we use new lidar datasets (collected by both drone and fixed-wing aircraft) to map the Eastern Denali Fault and the Tintina Fault in the
Yukon. In both areas we find evidence for Holocene fault offsets - which provides valuable information for both geothermal energy exploration and assessment of earthquake hazards. |
GEOSCAN ID | 330632 |
|
|