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2020 Annual Meeting Seismological Society of America Technical Sessions 27–30 April Albuquerque Convention Center Albuquerque, New Mexico Annual Meeting Announcement, 1095 2020 Annual Meeting Seismological Society of America Technical Sessions 27–30 April Albuquerque Convention Center Albuquerque, New Mexico PROGRAM COMMITTEE Tuesday, 28 April • Technical Sessions. The Co-Chairs of the 2020 SSA Annual Meeting are Rick • SSA Luncheon (open to all attendees). Awards Ceremony Aster of Colorado State University and Brandon Schmandt of to follow. Noon–1 pm, Hall 3. University of New Mexico. • Mentoring Luncheon (RSVP required with registration). Noon–1 pm, Hall 3. Meeting Contacts • SSA Awards Ceremony. 1:15–2:15 pm, Kiva Auditorium. • Lightning Talks. 6:30–7:30 pm, Kiva Auditorium (see page Technical Program Co-Chairs 1096). Rick Aster and Brandon Schmandt • Early-Career and Student Reception. 7:30–8:30 pm, [email protected] Ballroom B. Abstracts Wednesday, 29 April Rikki Anderson • Technical Sessions. 510.559.1784 • SSA Luncheon (open to all attendees). Public Policy [email protected] Lecture to follow. Noon–1 pm, Hall 3. • Women in Seismology Luncheon (RSVP required with Registration registration). Noon–1 pm, Hall 3. Mattie Adam • Public Policy Lecture. Speaker: Terry Wallace, Director 510.559.1781 Emeritus, Los Alamos National Laboratory, 1:15–2:15 pm, [email protected] Kiva Auditorium (see page 1100). • Joyner Lecture. Lecturer: Julian Bommer, Imperial Media Registration and Press Releases College of London. 6:15–7:15 pm, Kiva Auditorium (see Becky Ham page 1100). 602.300.9600 • Joyner Reception. 7:15–8:45 pm, Outdoor Plaza. [email protected] • Special Interest Group: Seismic Tomography 2020: What Comes Next? 8–9:30 pm, Room 215 + 220 (see page 1098). Exhibit and Sponsorship Opportunities • Special Interest Group: SOS: Save Our Seismograms. 510.525.5474 8–9:30 pm, Room 230 + 235 (see page 1098). [email protected] Thursday, 30 April PRELIMINARY SCHEDULE • Technical Sessions. Monday, 27 April • Luncheon. Noon–1:15 pm, Hall 3. • Workshops (see page 1097). Friday, 1 May • SSA Board of Directors Meeting • Field Trips (see page 1099). • Registration. 3–7:30 pm, Outside Ballroom C • Post-Meeting Workshop (see page 1098). • Welcome Reception. 5–6:30 pm, Ballroom B • Opening Lecture: Ross S. Stein, Ph.D., CEO & Cofounder of Temblor, Inc. (see page 1100). 6:30–7:30 pm, Room 115 doi: 10.1785/0220200043 Volume 91 • Number 2B • March/April 2020 • www.srl-online.org Seismological Research Letters | 1095 EVENTS Multi-Signature Ground- and Space Borne Observations: A Quick Forensic Analysis of the 21 Lightning Talks June 2019 Philadelphia Energy Solutions Refinery The Lightning Talks comprise an hour of 10 five-minute talks. Explosion The talks start at 6:30 pm on Tuesday, 28 April. Joshua Carmichael ([email protected]) On 21 June 2019 08:22 UTC, a fire at an oil refinery in Real-Time, Real Magnitudes, Why We Need GNSS Philadelphia, PA climaxed in the detonation of vaporized in Earthquake Early Warning propane fuel that produced an explosion and fireball (https:// Kathleen Hodgkinson ([email protected]) www.youtube.com/watch?v=yCXysi2g61Q). This fireball was Real-time GNSS measurements indicated the 2019 M7.1 resolved in the infrared band of the spaceborne Geostationary Ridgecrest, California, earthquake was ~M6.9 within 13 sec- Operational Environmental Satellite (GEOS) weather radar onds of the origin time. Why did it work so well for Ridgecrest? (https://www.space.com/philadelphia-refinery-fireball-seen- What does GNSS record that seismic doesn’t? We make the from-space.html), far above meteorological background levels. case for real-time GNSS in EEW. Residents located kilometers away from the refinery that did not all witness this fire tweeted that multiple explosions rattled The M6.4 Indios Sequence from the Trenches their homes during the time of the fire. While the United States Elizabeth A. Vanacore ([email protected]) Geological Survey catalogued no earthquakes coincident with Beginning on December 28th, 2019, holiday celebrations this event, seismic and infrasound stations recorded clear Puerto Rico were disrupted by earthquake activity along the waveforms ≤ 177 km from the refinery at times that acoustic Punta Montalva Fault. What followed was a complex earth- waves are predicted to arrive from-source, after the explosion quake sequence encompassing multiple faults in southwestern origin time. These seismic waveforms show consistent ellip- Puerto Rico including a M6.4 event on January 7, 2020. This tically-polarized correlation in the 2-10Hz band and provide sequence, now called the M6.4 Indios Sequence, included mul- strong evidence of Rayleigh waveforms. The presence of such tiple destructive earthquakes and generated fear amongst the seismo-acoustic signals at local distances (≤ 200 km) after the local populace. At the Puerto Rico Seismic Network, the staff explosion suggests that blast-generated air waves provided the and students ran a delicate balance between locating events, source of these ground-coupled, low group velocity Rayleigh maintaining operations, communicating with press and public waves. We promote these cumulative space-borne and ground and trying to find time to do the necessary science to provide observations that include unconventional sources (Twitter) as critical information to emergency responders and government a forensic, multi-signature testbed dataset for urban centered officials. Here the experience of the M6.4 sequence from the explosions on the East Coast. point-of-view of the responding regional network, PRSN, will be presented. Crowd-Sourcing Tsunami Warnings with Ship Position Data Fear and Loathing in Machine Learning Anne F. Sheehan ([email protected]) Sarah Albert ([email protected]) The high cost associated with deployment and main- The popularity of machine learning has increased dramat- tenance of cabled ocean bottom instrumentation and low ically in recent years. In seismology, peer-reviewed machine latency tsunami buoys is a limiting factor to subduction zone- learning research ranges from automated phase picking and wide expansion of tsunami warning systems. In the interim, event discrimination to the digitizing of analog records. non-traditional observation strategies have been suggested Despite these peer-reviewed studies, there is still a large including instrumentation of ship traffic in coastal regions. amount of skepticism surrounding its usefulness. Skeptics Ships routinely broadcast an automatic identification sys- argue that there is no way to tie results to the physical prop- tem (AIS) signal, which is used in vessel tracking and colli- erties of a signal, making the whole discipline a “black box” sion avoidance. These AIS signals are picked up by satellites, where anything goes. Far from it! Machine learning is a statis- including the recent proliferation of CubeSat constellations. At tical tool that can be powerful when used in the right context. any given time there are many tens of ships offshore Cascadia. This talk will introduce the statistical theory behind machine Here we illustrate what can be done with ship heading and learning algorithms with the goal of dissolving the “black box”. position data in a tsunami data assimilation framework. In the Steps to aid in determining whether a problem is suited for data assimilation method, long used in weather forecasting, machine learning and potential applications within the field of real-time observations are continuously assimilated to pro- seismology will also be discussed. SNL is managed and oper- duce a forecast. In tsunami data assimilation, seafloor pressure ated by NTESS under DOE NNSA contract DE-NA0003525. data, GPS buoy data, ship position data and other sources can be used to forecast a coastal tsunami, and a tsunami source model is not required. Future observation platforms for these 1096 | Seismological Research Letters www.srl-online.org • Volume 91 • Number 2B • March/April 2020 kinds of forecast systems might even include GNSS on floating With the advances in computer image processing, it is now offshore windfarms. possible to digitize these records more quickly than ever, and utilize them like almost any other modern digital time series. Oh Moment, Where Art Thou? Here, we present a brief overview of different media used to Peter M. Powers ([email protected]) record/store seismograms, and how analog data can be taken And other questions arising from a ten year odyssey in from paper to digital time series for exciting research. National Seismic Hazard Model development. Also, some unapologetic plugs for USGS products. The Great Lisbon Earthquake and the Problem of Evil The Potential of Using Fiber Optic Arrays for Daniel C. Bowman ([email protected]) Earthquake Magnitude Estimation According to Gottfried Leibniz, the problem of evil—why Noha S. Farghal ([email protected]) bad things happen to good people—was surely solvable, or Recent work showed the potential of using borehole at least understandable, in this “best of all possible worlds.” strainmeter records to estimate earthquake magnitudes Then came the Great Lisbon Earthquake of 1755, a catastro- and associated ground motions. These recent achievements phe not only for the city but for philosophy itself. This disaster show the value of the strain measurement in characterizing convinced many that moral and natural law are irrevocably earthquakes. However, installing a strainmeter in a borehole divorced. This separation persists to the present day, but we is costly and not always feasible, since it may not always be are not powerless. We
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