Online Research Seminars – Solid Earth 2

Following last week’s Hydrology session, we are pleased to announce the second Solid Earth session for this Friday, July 24, 2020 starting at 2:30 pm eastern time. Please note that due to scheduling conflict, the starting time of the remainder of the seminar series will no longer be 2 pm eastern time. The webinars will continue most Fridays this summer, with the next series of talks scheduled for Friday, July 31. A full schedule of the summer series can be found here. We invite you to follow the series on our FacebookTwitter and/or LinkedIn pages for the latest information.

The CGU-wide Annual General Meeting will follow next week’s talks from 3:45 pm to 4:45 pm eastern time. Other sections’ AGMs will follow over the coming weeks.

To attend this week’s research talks, please join via this link:

Passcode: 938442

Or iPhone one-tap :
    US: +13126266799,,85224561693#,,,,,,0#,,938442#  or +13462487799,,85224561693#,,,,,,0#,,938442#
Or Telephone:
    Dial(for higher quality, dial a number based on your current location):
        US: +1 312 626 6799  or +1 346 248 7799  or +1 408 638 0968  or +1 646 876 9923  or +1 669 900 6833  or +1 253 215 8782  or +1 301 715 8592
Webinar ID: 852 2456 1693
Passcode: 938442
    International numbers available:

You could also attend by watching our YouTube livestream.

This week’s research talks include:

“Seismic Anisotropy Variations Across Greenland: Evidence From Shear Wave Splitting”
Speaker: Mélanie Mathieu
Affiliation: Université du Québec à Montréal (student talk)
Time: 2:30 pm – 2:45 pm EDT
Session: Cratons and craton margins – formation, evolution and interactions
– New data for the seismic anisotropy beneath Greenland showed an interesting variation of the result which can be explained by more than one origin
– The results confirm the presence of two layers of anisotropy which increases the complexity of the results

“Evolution of the November 2018 M 4.5 seismicity sequence induced by hydraulic fracturing in Dawson Creek (British Columbia, Canada): Reactivation of multiple fractures”
Speaker: Andres Peña Castro
Affiliation: McGill University (student talk)
Time: 2:50 pm – 3:05 pm EDT
Session: Induced seismicity in North America
Hydraulic fracturing activities triggered earthquakes in deep and shallow faults.

“Investigating and comparing shear wave velocity structure and seismic anisotropy beneath the Tanzanian, Wyoming and North American cratons”
Speaker: Riddhi Dave
Affiliation: Université du Québec à Montréal
Time: 3:10 pm – 3:25 pm EDT
Session: Cratons and craton margins – formation, evolution and interactions
In this presentation, we take a detailed look at the seismic structure and radial anisotropy of the lower crust and uppermost mantle beneath the Tanzanian craton and provide a comparison with Wyoming and North American cratons.

“Linking subslab asthenospheric buoyancy and subduction dynamics to surface processes: Results from amphibious teleseismic tomography of the Cascadia subduction zone”
Speaker: Miles Bodmer
Affiliation: University of Oregon
Time: 3:30 pm – 3:45 pm EDT
Session: Multidisciplinary Studies of Subduction Zone Processes: Cascadia and beyond
I will present recent onshore-offshore teleseismic P-wave tomography results from the Cascadia subduction zone which show localized low-velocity anomalies beneath the subducting slab. These anomalies are interpreted to be localized upwellings and regions of increased buoyancy subslab. I will discuss how these buoyant features may influence the slab morphology, megathrust behavior, and forearc evolution, and what role they have in the along-strike segmentation of the Cascadia margin.

“Statistics and Forecasting of Aftershocks during the 2019 Ridgecrest, California, Earthquake Sequence”
Speaker: Robert Shcherbakov
Affiliation: University of Western Ontario
Time: 3:50 pm – 4:05 pm EDT
Session: Seismic Hazard and Earthquake Site Response
The 2019 Ridgecrest, California, earthquake sequence represents a complex pattern of seismicity that is characterized by the occurrence of a well defined foreshock sequence followed by a mainshock and subsequent aftershocks. In this work, a detailed statistical analysis of the sequence is performed. In addition, the problem of constraining the magnitude of the largest expected aftershocks to occur during the evolution of the sequence is addressed. The results indicate that the inclusion of the foreshock sequence into the analysis produces higher probabilities for the occurrence of the largest expected aftershocks after the M7.1 mainshock. Several statistical tests are applied to verify the forecast.