&
present
2022-2023 Geophysics Seminar Series

 

  Location: In-person (ES2093) and/or Zoom

Time: Tuesday afternoons (4-5 pm during school year, 4-5 for KEGS Virtual meeting, 3-4 pm during summer, unless otherwise noted)

Schedule (Temporary)
Rachel Newrick (CSEG Distingished Lecturer), Oct 20th TBA (hybrid)
Carl Tape (UAF), Oct 26th/TBA (hybrid)
Xiaowei Chen (Texas A\&M), Nov 15th/TBA (virtual)
Heiner Igel (LMU), Feb 9, 2023, Physics Colloquium
end of Feb: J. Tuzo Wilson Lecture
KEGS Talks (09/13, 10/11, 11/8, 12/13, 01/10, 02/14, 03/14, 04/11)
Kyubo Noh (University of Toronto): Jan-Mar 2023
Next year TBA: Lyal Harris, INRS, Quebec City


Dates reserved for KEGS talks: second Tuesday afternoon of the month
Important Dates: 09/08: fall classes start; 10/10: Thanksgiving; 11/7-11: fall reading week; 12/08: last day of fall classes; 01/09: spring classes start; 02/20-24: winter reading week; 04/10: last day of classes.

Other relevant seminar series at UofT: ES seminar (Thu noon), ES Rockfest (Fri 4pm, run by grads), Physics Colloquium (Thu 4pm), Brewer-Wilson Seminar (Fri noon, run by grads), Center for Global Change Science (CGCS) Seminars (dates: 09/27, 10/11, 10/25, 11/15, 11/29, 12/06, 01/17, 01/31, 02/14, 02/28, 03/14, 03/28, 04/11, every second Tue 4 pm), Centre for Research in Earth System Science Seminars (CRESS) at UTSC (Friday 4pm), UTM CPS Colloquium (Wed 3-4 pm)
For a list of Geoscience events across GTA, check out the GTA Geoscience Events Calendar. Also check out the websites for Toronto Geological Discussion Group (TGDG), Canadian Exploration Geophysical Society (KEGS) and KEGS Foundation.

External webinars of interest: IRIS webinars (Youtube Channel), CIG webinars (Youtube Channel), AGU Webinars, SEG Near surface global lecturers, SEG ON DEMAND (you may need to be an SEG member to view)


Upcoming Talks

Title: Great earthquake rupture segmentation at the eastern Alaska Aleutian megathrust by subducted seamounts

Date/Time: Nov 29, 2022, 4-5 pm
Location: ES2093
Speaker: Prof. Mladen Nedimovic
Affiliations: Dalhousie University/span>




Title: Probing earthquake triggering and source processes through multiscale analyses of induced seismicity

Date/Time: Nov 15, 2022, 4-5 pm
Location: virtual only (see email for zoom link)
Speaker: Prof. Xiaowei Chen
Affiliations: Texas A\&M University

Abstract: In the past decade, the seismicity rate in Oklahoma experienced rise, peak, and decline as a result of varying industry operations. This large-scale “unintentional” earthquake experiment provided us with rich datasets to further probe earthquake triggering and source processes. In this presentation, I present multi-scale analyses of induced seismicity in Oklahoma by combining several studies, and their implications for better understanding of earthquake processes in different tectonic settings. Spatiotemporal patterns of seismicity at regional scale shows systematic regional variations of hydraulic properties of the Arbuckle Group within different pressure units. Spatiotemporal patterns of seismicity within individual sequences exhibit similar behaviors with natural earthquake swarms in tectonically active regions. Systematic large-scale analyses of stress state show that a majority of reactivated seismogenic faults are optimally oriented. However, detailed analyses of stress state evolutions within representative sequences reveal diverse fault planes distributions within swarm-type sequences, and that fault architecture influences sequence evolutions. Focusing on the well-recorded Guthrie sequence in central Oklahoma, diverse triggering mechanisms are observed. The largest event in this sequence shows considerable rupture complexity using finite slip inversion methods. Comparison with slip inversions for earthquakes in different tectonic regions indicates that the level of complexity is similar to earthquakes in low deformation rate regions, suggesting fault characteristics control rupture patterns.


Title:

Date/Time: Jan 17, 2022, 4-5 pm (Tentative)
Speaker: Dr. Bryan James
Affiliations:

Abstract: TBA


Physics Colloquium: Earth's Rock and Roll: Rotational Motion in geodesy and seismology

Date/Time: Feb 16th (Thursday), 2023, 3-4 pm
Speaker: Prof. Heiner Igel
Affiliations: Department of Earth and Environmental Science, Ludwig-Maximilians-University Munich, Germany

Abstract: The unwanted noise of ring lasers (whenever seismic wave fields perturb their measurements of Earth’s rotation rate) has led to a new field: rotational seismology. The additional ground motion components (i.e. rotation around three orthogonal axes) had been widely ignored, as they are very difficult to measure. Yet, when combined with collocated standard seismometers (three components of displacement) a wealth of information can be recovered from the wavefield. We will report on these new developments with applications in seismic tomography, earthquake physics, planetary seismology, engineering, and other fields. The bottom of the tetradedral-shaped ROMY ring laser measuring Earth’s rotation and rotational ground motions. The sensor is located in the Geophysical Observatory Fürstenfeldbruck near Munich. (Youtube Video from Science Magazine; further Info)


Title: 2022-2023 J. Tuzo Wilson Lecture

Date/Time:Feb 28 2023, 7:30-9 pm
Location: Isabel Bader Theatre, Victoria University
Speaker: Prof. Roel Snieder
Affiliations: Colorado School of Mines

Abstract:


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Past Talks


Title: Alaska Earthquakes and Earth Structure in the EarthScope Era (2014-present)

Date/Time: Oct 26, 2022, 3-4 pm (Wednesday)
Speaker: Prof. Carl Tape
Affiliations: University of Alaska, Fairbanks

Abstract: The subsurface structure of Alaska contains clues to its formation and evolution over geologic time. Today, tectonic forces of subduction and collision are manifest in earthquake activity across the entire state. The NSF-sponsored EarthScope Seismic Array was fully deployed in 2017, enabling new high-quality geophysical data collection in large, remote regions of the state. I will discuss recent and ongoing studies of earthquakes and seismic imaging in Alaska, with a focus on crustal faulting. I will also convey how 3D seismic wavefield simulations can be used to understand the complexities of the recorded wavefield, as well as to guide improvements to tomographic models of crustal and upper mantle structure.


2022 CSEG Distingished Lecture: Geophysics..the future is so bright, we have to wear shades

Date/Time: Oct 20th 2022 (Thursday), 4-5 pm
Speaker: Dr. Rachel Newrick


Abstract: The world is facing many global challenges: poverty, insufficient clean water supply, hunger and a lack of energy security amongst others. To tackle them, the world needs critical thinkers, who are curious and inventive. Utilizing a variety of skills and technologies, geophysicists play a significant role in helping the world meet the 2030 UN sustainable development goals. Geophysicists interrogate the subsurface to locate oil, gas, minerals, water, brine, subsurface reservoirs for carbon sequestration, and to improve our understanding of hazards, earthquakes etc. The thought process that we use in exploration can be used as we look forward to the future, progressing oddities to leads and prospects. The future is bright for geophysicists, and for the world because geophysicists are helping address many global challenges.