Technical Short Course
Strain Accumulation and Release from GNSS
June 15-17, 2026
Time: 9 AM–1 PM PT
Virtual
About
Program Overview
Led by members of the Coupling, Seismicity, and Slow Slip (C3S) working group, this technical short course provides requisite tools for recognizing how earthquake cycle signatures in the Cascadia Subduction Zone are expressed in geodetic observations. It will introduce basic processing of geodetic time series to interpret longer-term strain accumulation processes and slow slip events. It will cover extracting velocities and displacements from geodetic time-series observations and introduce basic inverse methods to use geodetic data to constrain fault slip patterns. Analysis of geodetic data offers opportunities for students to gain geoscience-specific skills, but also data science skills, and will contribute to improving our understanding of the spectrum of slip processes on the subduction interface.
The course will include lectures and introduction to Python computing tools, as well as free time for participants to gain hands-on experience with the tools using Jupyter notebooks.
Learning Objectives
By the end of this short course, participants will be able to:
- Understanding basic GNSS time series signals
- Load and visualize GNSS time series data
- Use algorithms to estimate interseismic, coseismic, and slow slip signatures
- Use geodetic displacement fields to estimate fault slip patterns
- Use geodetic velocity fields to estimate interseismic coupling patterns
- Understand how viscoelastic processes influence observed deformation
Highlight Your Skills with a Digital Badge: Participants who attend 100% of the course earn a credential through Credly issued by EarthScope Consortium that verifies your achievements. The badge showcases the knowledge and skills you’ve gained and can be shared online, added to resumes, or displayed on professional and social media profiles to support your career growth.
Agenda
The course runs from June 15–17 and includes 3 main sessions over 3 days, with each daily session lasting 4 hours.
Day 1: Monday June 15
- 9:00 AM = GNSS Scientific Motivation & Highlights
- Overview of Course Topics & Activities
- 10:00 AM = Basic Ranging & Positioning
- 10:30 AM = 10 minute break
- 10:40 AM = Time Series & Decomposition
- Build up a time series with noise, linear, annual & semi-annuals, offsets terms
- Decompose that synthetic time series into its individual terms, make sure they match
- Decompose ALBH.lat, lon & rad into its component pieces, discuss
- 11:50 AM = 10 minute break
- 12:00 PM = C3S Transient Exercise
- 1:00 PM = Course adjourns for the day
- 1:00 PM – 1:30 PM = OPTIONAL Q&A
- Each instructor will join a breakout room to answer follow-up questions about the course material or related topics. Participants are welcome to join the breakout room of the instructor they would like to speak with. This will provide an opportunity for more focused discussions and individual questions.
Day 2: Tuesday June 16
- 9:00 AM = Fault Modeling Fundamentals
- Relating fault slip to surface displacement
- Representing fault geometry
- 10:00 AM = Forward Model Exercise
- 10:30 AM = 10 minute break
- 10:40 AM = Inverse Modeling Exercise
- Regularization
- Assessing fit to data
- Assessing estimated slip distribution
- 11:50 AM = 10 minute break
- 12:00 PM = Block Modeling Demonstration
- Theoretical background
- Demonstration of tools for model construction, estimation, and result visualization
- 1:00 PM = Course adjourns for the day
- 1:00 PM – 1:30 PM = OPTIONAL Q&A
- Each instructor will join a breakout room to answer follow-up questions about the course material or related topics. Participants are welcome to join the breakout room of the instructor they would like to speak with. This will provide an opportunity for more focused discussions and individual questions.
Day 3: Wednesday June 17
- 9:00 AM = Earth Structure Effects and Slip Inversion Modeling with GeoSlip2D
- “Higher order” Earth structure effects on surface deformation and 2D model approximations
- Introduction to GeoSlip2D python package
- Demonstration of slip inversion notebook
- Exercise: experiment with slip inversion parameters, fault geometry, etc.
- 10:00 AM = Layered Elastic Models
- Motivation and demonstration of layered elastic models notebook
- Exercise
- 10:30 AM = 10 minute break
- 10:40 AM = Compliant Wedge Model
- Motivation and demonstration of compliant wedge model notebook
- Exercise: explore influence of compliant wedge and subducting slab compliance
- 11:50 AM = 10 minute break
- 12:00 PM = Viscoelastic Earthquake Cycle Models
- Motivation and demonstration of viscoelastic earthquake cycle models notebook
- Exercise: compute a range of cycle models for different viscosities, recurrence times, and times since last earthquake
- 12:50 PM = Wrap Up
- 1:00 PM = Course adjourns for the day
- 1:00 PM – 1:30 PM = OPTIONAL Q&A
- Each instructor will join a breakout room to answer follow-up questions about the course material or related topics. Participants are welcome to join the breakout room of the instructor they would like to speak with. This will provide an opportunity for more focused discussions and individual questions.
Application
Prerequisites
- This course is for upper-level undergraduate students, graduate students, postdocs, and professionals in the field of geodesy and tectonics who have specific research or application needs for using geodetic data to image fault slip processes.
- An individual computer that has an internet browser and a minimum stable internet connection speed of 5 Mb/s.
- Ability to explain how this course aligns with your current research or technical goals.
Recommended Background
To get the most out of this course, participants are encouraged to have:
- Intermediate Python computing skills including:
- Use of numpy and pandas
- Familiarity with working in a development environment (conda, pixi, etc.)
- Proficient knowledge in Jupyter notebooks
- General understanding of linear algebra and inverse theory
- Basic understanding of the earthquake cycle and tectonic settings
The application closes April 15, 2026 at 11:59 pm Pacific Daylight Time.
For questions contact GEI Program Manager Shannon Fasola (sfasola@uoregon.edu).
Instructors
Jack Loveless: Smith College
Brendan Crowell: Ohio State University
Kaj Johnson: Indiana University Bloomington
Tim Melbourne: Central Washington University