BSL Research into the Dynamic Earth
Research Update: Aseismic Creep on the Mendocino Fault Zone
Continuing their research on repeating earthquakes at the Mendocino Triple Junction, the place where the Pacific, North American, and Gorda plates collide, BSL researchers Kathryn Materna, Taka'aki Taira, and Roland Bürgmann have further characterized the "creep" on the Mendocino Fault Zone at the edges of the Pacific and Gorda plates. Their most striking finding suggests a region of persistent aseismic slip on the Mendocino Fault Zone just offshore of northern California. Their research also identifies sequences of repeating earthquakes that can be used in the future to study transient aseismic creep events, such as triggered creep in response to nearby earthquakes. They present their findings in this month's Geophysical Research Letters. Read more about their research.
Seismic Noise: Taka'aki Taira, Michael Manga, and others are studying the speed of seismic waves beneath the Salton Sea to learn more about very shallow earth structure. This new tool is giving us clues to the inner workings of volcanoes and geothermal fields.
Fluids in Geophysical Processes: Why do volcanoes (only sometimes) erupt explosively? How do distant earthquake affect volcanic and geyser eruptions? How do pyroclastic flows interact with water? The Manga group studies geological processes involving fluids, including problems in physical volcanology, hydrogeology, and geomorphology, in an attempt to develop a better quantitative understanding of physical processes operating in the Earth.
InSAR and the Hayward Fault: The Bürgmann group modeled the Hayward and Calaveras Faults using InSAR radar satellite measurements. Results indicate the faults should be treated as a single system with potential to generate events with magnitudes significantly greater that 7, posing a higher seismic hazard than previously considered.
Seismic Sources: The seismic source (Dreger) group focuses on the use of seismic waveform data to investigate seismic sources (tectonic and non-tectonic), wave propagation, and various geophysical inverse problems, as well as developing robust automated procedures to analyze earthquakes as they occur. Current projects include studying induced seismicity at the Louisiana sinkhole and monitoring seismicity and ambient noise at the Geyers geothermal field.
ShakeAlert: ShakeAlert is the earthquake early warning system under construction in the United States. The BSL has been part of this effort since its inception in 2001, and continues to work towards public alerts.
MyShake MyShake is a global smartphone-based seismic network from the Allen group. The goal: provide global earthquake early warning.
Alaska: Alaska is the last frontier for Earthscope. As the dense USArray spreads across the state we start to observe the dynamic processes responsible for the region’s earthquakes and volcanoes.
Fluids in Geodynamics: How does the internal structure of the mantle affect the formation and evolution of mantle plumes? Are there compositionally distinct layers at the base of the mantle? and do they influence the formation of plumes? Michael Manga's group studies the role of fluids in geodynamics.
Cascadia: The enigmatic Cascadia Subduction Zone lacks the continuous seismic activity seen at most convergent plate boundaries. The Allen group uses a variety of Earth imaging techniques to understand tectonic processes in the region.
Earthquakes and the Rainfall Cycle
Chris Johnson and Roland Bürgmann's research is featured in the video below.