Author Archives: Maggie

If a fault moves at the bottom of the ocean, can anyone hear it?

A few hundred miles off the coast of Oregon, and under several miles of sea water, lies the Blanco Transform Fault. It is between the Juan de Fuca and the Gorda tectonic ridges. Ocean transform faults such as this one connect seafloor ridges and are where volcanic activity creates new oceanic crust. This fault is more seismically active than many faults on land, generating over 1,600 earthquakes in a single year (between 2012 and 2013). Did you feel anything then?

Location and tectonic setting of the Blanco Transform Fault.

Vaclav Kuna, a doctoral candidate in seismology in the College of Earth, Ocean and Atmospheric Sciences working with Dr. John Nabelek, is studying this fault—how it slips and how it moves, and whether its motion is seismic (involving an earthquake) or aseismic (slow movement without an earthquake). A collection of movements is called a seismic swarm. The hypothesis is that prior to large, seismic motions, there are small, aseismic motions. Through his research, Vaclav hopes to decipher what occurs in a swarm, and discover if there is a pattern in the fault’s motions.

The model Vaclav is working to develop of the mode of slip of the Blanco Transform Fault. We believe that slow (non-seismic) creep occurs at depth in the fault beneath the Moho and loads the shallower part of the fault. The slip at depth most likely triggers the big earthquakes, that are preceded by foreshocks associated with creep.

This is different than predicting earthquakes. As a seismologist, Vaclav is trying to understand and report on the behavior of a fault, not predict when a certain magnitude earthquake will occur. However, other researchers can use findings like Vaclav’s to create prediction models which are necessary for earthquake damage mitigation and increasing public safety during and after earthquake events.

To look for patterns in the fault’s motions, Vaclav analyzes a year’s worth of data from seismometers and pressure gauges that were deployed from a ship to the fault at the ocean floor several years ago. The seismometers measure the velocity of a fault’s movement in three directions (two horizontal and one vertical), and the pressure gauges act as microphones capturing sound waves. The data can be decomposed into a series of many waves (like sine or cosine waves). Vaclav can track these waves in the sensors deployed along this fault and determine the variability of motion in both time and space. After the sensors are finished collecting the data, a remote control turns on an electrical circuit, that triggers a corrosion reaction and severs a wire holding a large weight that is keeping the sensors at the ocean floor—which seems like something taken right out of a spy movie.

Deployment of ocean bottom seimometers (yellow packets) at the Blanco Transform Fault. Every packet includes a 3-component seismometer and a differential pressure gauge (which acts as a microphone).

So why would a researcher monitor a fault that is miles underwater when there are faults on land? Ocean transform faults are less complex than faults on land, making them desirable to study in order to answer fundamental questions about fault behavior. In addition, they are extremely seismically active and generate earthquakes more frequently than faults on land. However, ocean transform faults are evidently more difficult to observe, and because the process of planning for and conducting fieldwork is time-intensive, most of the data Vaclav uses were gathered before he was enrolled at OSU. In turn, Vaclav helps deploy sensors and gather data for future students to analyze at a number of different faults around the world.

Vaclav at a station deployment at the Kazbegi mountain, Georgia (Caucasus mountain range).

Vaclav did his Bachelor’s and Master’s degrees in Geophysics in Prague, Czech Republic. He was motivated to study Geophysics because there is a lot that is unknown about how the Earth’s tectonic plates move, and many people living near these faults. In his spare time, Vaclav likes swimming, running, skiing and kayaking. After completing his PhD, Vaclav wants to find a job working towards hazard-related mitigation to help people who are vulnerable to the damages caused by earthquake hazards.

How high’s the water, flood model? Five feet high and risin’

Climate change and the resulting effects on communities and their infrastructure are notoriously difficult to model, yet the importance is not difficult to grasp. Infrastructure is designed to last for a certain amount of time, called its design life. The design life of a bridge is about 50 years; a building can be designed for 70 years. For coastal communities that have infrastructure designed to survive severe coastal flooding at the time of construction, what happens if the sea rises during its design life? That severe flooding can become more severe, and the bridge or building might fail.

Most designers and engineers don’t consider the effects of climate change in their designs because they are hard to model and involve much uncertainty.

Kai at Wolf Rock in Oregon.

In comes Kai Parker, a 5th year PhD student in the Coastal Engineering program. Kai is including climate change and a host of other factors into his flood models: Waves, Tides, Storms, Atmospheric Forcing, Streamflow, and many others. He specifically models estuaries (including Coos and Tillamook Bay, Oregon and Grays Harbor, Washington), which extend inland and can have complex geometries. Not only is Kai working to incorporate those natural factors into his flood model, he has also worked with communities to incorporate their response to coastal hazards and the factors that are most important to them into his model.

Modeling climate change requires an immense amount of computing power. Kai uses super computers at the Texas Advanced Computing Center (TACC) to run a flood model and determine the fate of an estuary and its surroundings. But this is for one possible new climate, with one result (this is referred to as a deterministic model). Presenting these results can be misleading, especially if the uncertainty is not properly communicated.

Kai with his hydrodynamic model grid for Coos Bay, Oregon.

In an effort to model more responsibly, Kai has expanded into using what is called a probabilistic flood model, which results in a distribution of probabilities that an event of a certain severity will occur. Instead of just one new climate, Kai would model 10,000 climates and determine which event is most likely to occur. This technique is frequently used by earthquake engineers and often done using Monte Carlo simulations. Unfortunately, flooding models take time and it takes more than supercomputing to make probabilistic flooding a reality.

To increase efficiency, Kai has developed an “emulator”, which uses techniques similar to machine learning to “train” a faster flooding model that can make Monte Carlo simulation a possibility. Kai uses the emulator to solve flood models much like we use our brains to play catch: we are not using equations of physics, factoring in wind speed or the temperature of the air, to calculate where the ball will land. Instead we draw on a bank of experiences to predict where the ball will land, hopefully in our hands.

Kai doing field work at Bodega Bay in California.

Kai grew up in Gerlach, Nevada: Population 206. He moved to San Luis Obispo to study civil engineering at Cal Poly SLO and while studying, he worked as an intern at the Bodega Bay Marine Lab and has been working with the coast ever since. When Kai is not working on his research, he is brewing, climbing rocks, surfing waves, or cooking the meanest soup you’ve ever tasted. Next year, he will move to Chile with a Fulbright grant to apply his emulator techniques to a new hazard: tsunamis.

To hear more about Kai’s research, be sure to tune in to KBVR Corvallis 88.7 FM this Sunday May, 27 at 7 pm, stream the live interview at kbvr.com/listen, or find it in podcast form next week on Apple Podcasts.

This includes you!

A graph illustrating why it is important to incorporate inclusive considerations early in the design process where they will do the most good. If it is kept for a later stage as it generally has been, the products will end up more expensive and less effectively inclusive.

Jessica Armstrong is a PhD candidate in her last year in the Design Core of the Department of Mechanical, Industrial and Manufacturing Engineering working to give product designers more information about customer needs so that they can create a more inclusive product design. Generally, products are conceived out of a need, and their design is based on the eventual user(s). The term inclusive design, similar to universal design, aims to design products for people with a varying range of abilities from the start. Making it possible to incorporate inclusive considerations early in the design process, when they will most benefit the design, and at the lowest cost, is a major part of the work. Jessica’s research goal is to build a framework that designers can follow to allow them to easily design as inclusive products as possible.

A picture of Jessica in the motion restriction suit.

To do this, Jessica, advised by Dr. Rob Stone, uses a motion restriction suit (tested during her M.S. degree at OSU) to test users’ experiences using kitchen gadgets. The suit restricts motion of the upper body by stiffening movements of the fingers, wrists, elbows, abdomen, and shoulder. They are investigating what they have termed “surrogate experiences”, or allowing a research subject (surrogate) to simulate the actual target users and their needs. Jessica is able to record a user’s experience with the kitchen gadget and identify any difficulties in products user interactions, the products actions and design, and the suit’s restriction.

 

 

 

Jessica Armstrong, at her first Design Engineering Technical Conference.

Jessica grew up in Boise, Idaho wanting to become an astronaut. Very much interested in physics and engineering, she moved to Corvallis for her Bachelor’s degree in Engineering Physics. She took a break from studying while her husband worked on his Entomology MS degree at Washington State University. During that time, she worked as a telephone interviewer for WSU’s Social and Economic Sciences Research Center where she interviewed people over the phone for the various studies they were conducting. She then moved back to OSU to pursue her MS and then PhD in Mechanical Engineering, and specifically focusing on design. She acquired a minor in IE Human Systems Engineering, as she finds the human aspect of engineering fascinating. While not working on research, Jessica sings alto and tenor in OSU’s University Choral and is the Treasurer for the OSU Physicists for Inclusion in Science group.

Her interest in space has not dissipated and she aims to work for a private space company after completing her degree. She hopes her doctoral research will eventually be used to encourage inclusivity in space travel and everyday life.

Tune in at 7 pm this Sunday March, 11 to hear more about Jessica’s research and journey to graduate school. Not a local listener? Stream the show live online!