Understanding Natural Recurrence of Earthquakes and Slip over Time: How Can Geologic Slip, Slip-Rate and Paleoseismic Data Advance Earthquake Models?
Date: June 1-3, 2026
Location: Pismo Beach, CA
Workshop Organizers: Sally McGill, Kim Blisniuk, Michael Oskin, Scott Marshall
SCEC Award: 26054
Workshop: This SCEC workshop, to be held in Pismo Beach, California on June 2-3, 2026, will convene earthquake geologists and modelers to address key limitations in how geologic observations of faulting and past earthquakes are incorporated into earthquake-cycle, seismic hazard, and geodetic models. A central focus will be the improved curation, organization, and interpretation of geologic and geometric fault and earthquake datasets to better support model testing and validation.
The specific goals of the workshop are to:
The primary outcome of the workshop will be a written planning document that defines the scientific and data priorities for a new community effort focused on Understanding Natural Recurrence of Earthquakes and Slip over Time (UNREST). The UNREST plan will articulate priorities for new or enhanced open‑source geologic cyberdatabases needed by the modeling community, and will outline collaborative research directions to be pursued jointly by geologists and modelers.
Field Trip (optional): An optional all-day field trip is planned for June 1, with check-in at 07:30 and departure at 08:00 from the hotel. The itinerary begins with a visit to the Carrizo Plain to examine key features of the San Andreas Fault. Stops will focus on constraints on fault slip rate, evidence of recent surface-rupturing earthquakes, and implications for earthquake timing. The trip will then proceed westward toward the central Coast region, with additional observations of active fault systems and regional seismic hazard considerations. The day concludes at the Diablo Canyon Nuclear Power Facility near Pismo Beach, where discussions will address the interaction between active tectonics, site characterization, and infrastructure risk assessment.
Participants: We welcome applications from, and aim to achieve a balanced representation of, participants from two complementary research communities:
We also seek a balance across career stages, including graduate students, early-career researchers, and established investigators, to promote cross-generational exchange and collaboration. Workshop capacity is limited to 35 participants, who will be selected based on their statement of interest and the potential contribution to the workshop objectives.
Accepted participants will be notified by April 24, 2026, with details on registration payments, hotel reservations, and additional travel support if applicable.
The workshop registration fee is $135, which covers venue expenses, lunch, and coffee breaks on the workshop days (June 2-3).
The optional field trip is an additional $110 fee, which covers transportation, lunch and snacks during the field trip on June 1.
Applicants should complete the travel support section carefully as part of the application process. Students, early‑career researchers, and participants without institutional funding are especially encouraged to apply for travel support. Subject to available funding, SCEC travel support may include travel to the workshop venue, lodging and/or meal expenses.
All times below Pacific Time (UTC -7)
| Time | Agenda Item | Speaker | |
|---|---|---|---|
| 17:00 - 20:00 | Arrival and check-in for those going on optional June 1 field trip | ||
| Time | Agenda Item |
|---|---|
| 07:30 - 08:00 | Field trip check-in |
| 08:00 - 17:00 | Field trip to Diablo Canyon Power Plant and San Simeon fault, led by Kim Blisniuk and Mike Oskin |
| 17:00 - 20:00 | Arrival and check-in for those attending June 2-3 workshop only |
| Time | Agenda Item | Presenter |
|---|---|---|
| 08:00 - 08:15 | Introduction: overview of the workshop goals and agenda | |
| Session 1: Geologic data needed for improvement of time independent seismic hazard models | ||
| 08:15 - 08:30 | Invited: TBD | Ned Field |
| 08:30 - 08:45 | Invited: Use of earthquake geology data in the USGS National Seismic Hazard Model | Alex Hatem |
| 08:45 - 09:00 | Invited: Do earthquake ruptures propagate through the creeping section of the San Andreas Fault? Evidence from geology | Belle Philibosian |
| 09:00 - 09:10 | TBD (Impact of omitting questionable events in paleoseismic records) | Devin McPhillips |
| 09:10 - 09:15 | Quantifying Fault Offset Uncertainty from Displaced Landforms: Case Studies from Western North America | Veronica Prush |
| 09:15 - 10:00 | Large‑group discussion | |
| 10:00 - 10:15 | Break | |
| Session 2: Geologic data needed for validation of earthquake catalog simulators and time-dependent seismic hazard models | ||
| 10:15 - 10:30 | Invited: Earthquake simulators and geological data constraints: current uses and opportunities for further valuable inputs | Bruce Shaw |
| 10:30 - 10:45 | Invited: TBD (Long paleoseismic records and modes of earthquake cycle behavior) | Mike Oskin |
| 10:45 - 11:00 | Invited: TBD (incremental slip-rate behavior of isolated faults with faults embedded within complex systems of mechanically complementary faults) | James Dolan |
| 11:00 - 11:05 | TBD (Episodic deformation in Santa Maria Basin) | Nate Onderdonk |
| 11:05 - 12:00 | Large group discussion | |
| 12:00 - 13:00 | Lunch at the hotel (hosted by SCEC) | |
| Session 3: Geologic data needed for comparison to geodetic and/or mechanical deformation models | ||
| 13:00 - 13:15 | Invited: TBD | Kaj Johnson |
| 13:15 - 13:25 | TBD (Viscoelastic earthquake cycle models, 'ghost transients', and how large earthquakes and long interevent times are required to perturb the interseismic velocity field enough to affect geodetically-inferred slip rates.) | Liz Hearn |
| 13:25 - 13:35 | Invited: TBD (Why we need a slip-rate database and more than one rate per fault) | Scott Marshall |
| 13:35 - 13:45 | TBD (SoCal traction evolution, pre-earthquake stress conditions and incomplete stress drops) | Grasshopper (Emery) Anderson-Merritt |
| 13:45 - 14:45 | Large group discussion | |
| 14:45 - 15:00 | Break | |
| Session 4: Setting priorities for the UNREST community effort (Part 1) | ||
| 15:00 - 15:30 | TBD (Setting priorities for the proposed UNREST TAG and explanation of tasks for breakout groups) | Mike Oskin |
| 15:30 - 16:00 | General discussion | |
| 16:00 - 17:00 | Small‑group breakout discussions (assigned groups) | |
| Group A: Geologic data needed for improvement of time independent seismic hazard models | ||
| Group B: Geologic data needed for validation of earthquake catalog simulators and time-dependent seismic hazard models | ||
| Group C: Geologic data needed for comparison to geodetic and mechanical models | ||
| Group D: Geologic data needed for validation of dynamic rupture models and multi-cycle earthquake models |
| Time | Agenda Item | Presenter |
|---|---|---|
| 08:00 - 08:15 | Introduction to Day 2 | |
| Session 5: Geologic data needed for validation of dynamic rupture models and multi-cycle earthquake models | ||
| 08:15 - 08:30 | Invited: TBD | Alice Gabriel |
| 08:30 - 08:45 | Invited: TBD (Synchronization and alternation as modes of fault interaction) | Alba Rodriguez Padilla |
| 08:45 - 08:55 | TBD (The past 1100 years of large earthquakes on the San Andreas fault system) | Tom Rockwell |
| 08:55 - 09:05 | TBD (Integration of geologic data into dynamic rupture models) | Julian Lozos |
| 09:05 - 09:15 | Use of SAF-SJF paleoseismic data in multicycle earthquake models | Kate Scharer |
| 09:15 - 09:20 | TBD (Dynamic rupture modeling of the Newport Inglewood fault: explaining complex rupture paths) | David Oglesby |
| 09:20 - 09:25 | TBD (Splay faulting as a potential indicator of rupture direction) | Nadine Reitman |
| 09:25 - 09:30 | TBD (3D frictional-viscous earthquake-cycle modelling of the Cascadia subduction zone) | Zhang Wenqiang |
| 09:30 - 10:15 | Large Group Discussion | |
| 10:00 - 10:30 | Break | |
| Session 6: Setting priorities for the UNREST community effort (Part 2) | ||
| 10:30 - 11:45 | Small-group break-out sessions (sign up for the group of your choice) | |
| Group A: Geologic data needed for improvement of time independent seismic hazard models | ||
| Group B: Geologic data needed for validation of earthquake catalog simulators and time-dependent seismic hazard models | ||
| Group C: Geologic data needed for comparison to geodetic and mechanical models | ||
| Group D: Geologic data needed for validation of dynamic rupture models and multi-cycle earthquake models | ||
| 11:45 - 13:00 | LUNCH in breakout groups at the hotel (hosted by SCEC) | |
| Session 7: Building and sustaining the UNREST community | ||
| 13:00 - 13:20 | TBD (Cyberinfrastructure for SCEC-hosted databases: slip-rate, paleoseismology, historic ruptures, date of latest event, fault geometry, others?) | Scott Marshall |
| 13:20 - 13:50 | Large-group discussion | |
| 13:50 - 14:10 | Summaries (up to 5 minutes each) from break-out groups A, B, C and D | |
| 14:10 - 15:10 | Large group discussion and concluding remarks |
The Statewide California Earthquake Center (SCEC) fosters a diverse and inclusive community where everyone feels safe, productive, and welcome. We expect all participants in SCEC-supported events to uphold this commitment by adhering to the SCEC Activities Code of Conduct.
The SCEC Annual Meeting brings together 400-500 participants worldwide to share breakthroughs, assess progress, and chart a collaborative path for earthquake science. All of the Center activities are presented, analyzed, and woven into a set of priorities for SCEC to pursue in the future.