Site Characterization of Alaska Transportable Array Stations in the Yukon, Canada Using H/V Ratios from Noise and Earthquake

Session: Near-Surface Effects: Advances in Site Response Estimation and Its Applications [Poster]
Type: Poster
Date: 4/28/2020
Time: 08:00 AM
Room: Ballroom
Description: 

The Northern Canadian Cordillera in the Northern Yukon Province comprises the North American Craton to the east and several sedimentary basins to the west of the Richardson Mountains. We investigate site amplifications using H/V ratios from noise windows in the Yukon, Alaska, at 23 Alaska Transportable Array seismic stations and two permanent stations. Preliminary results from pre-earthquake noise windows show relatively flat amplitude spectrums at frequencies from 1-10 Hz at three stations located just south of the Mackenzie Mountains, Yukon, Canada. The majority of the sites show peaks in amplitude at 1-3 Hz centered at 2 Hz. Two stations located on opposite sides of the Richardson Mountains show high amplitude ratio peaks of ~3 at 2 Hz. These amplifications are related to surface and subsurface geology and any impedance contrasts that exist beneath the stations. We plan to lengthen the time observation windows to 60 seconds around a database of S-wave arrivals developed for a separate study and calculate the ratio using the same time window on the vertical component. We also plan to expand the range of frequencies examined and correlate peaks in the spectra with geological maps and topography in the Yukon.

Presenting Author: Nicole L. Clizzie

Authors