August 20, 2009
A weekly feature provided by scientists at the Hawaiian Volcano Observatory.
HVO gets a brief look at seismology's promising future.
Opportunities to meet and become better acquainted with new colleagues are important and valuable in all organizations. This week, the Hawaiian Volcano Observatory (HVO) had the opportunity to welcome David - or Dave- Shelly, currently a post-doctoral researcher with the U. S. Geological Survey's (USGS) earthquake hazards group in California. He will soon join the USGS volcano hazards team as part of the Long Valley (California) Observatory.
The focus of Dave's recent research has been low-frequency earthquakes and seismic tremor in non-volcanic environments, and especially their relationship to the faulting cycle of large earthquakes. This includes "slow earthquakes," or significant fault movement that has been observed between large earthquakes. Dave's work has been a big part of a Pacific-wide if not global search for, and study of, these seismic signals and relationships to episodic fault movement. For the innovation that is associated with, and the insights that have resulted from his work, the Seismology Section of the American Geophysical Union (AGU) awarded to Dave its 2008 Keiiti Aki Young Scientist Award.
While he was a graduate student at Stanford, Dave spent the summer of 2005 in Japan, studying and working at the Graduate School of Science of the University of Tokyo. This exchange visit was supported by the U.S. National Science Foundation (NSF) and the Japan Society for the Promotion of Science (JSPS).
That summer, Dave shared an office at the University of Tokyo with Takuji Yamada. Takuji's Ph.D. research focused on relationships between small and large earthquakes, with an opportunity to study earthquakes from deep gold mines in South Africa. In the gold mine, it is possible to record earthquakes on instruments that are quite close, where the recorded signals more purely reflect the physics of the earthquake.
Takuji has been working in Hawai`i at HVO as a JSPS research associate since April 2008. His work at HVO has led to a recently completed study of the October 2006 Kiholo Bay earthquake and its aftershocks and how details of the fault movement correlate with aftershock locations and properties. In recognition of his earlier work, the Seismological Society of Japan named Takuji its recipient of the 2008 Early Career Seismologist Award. Takuji received the award in May 2009, and in October he will return to Japan to give a lecture as part of this special recognition.
Although HVO enjoys a large number of visitors, having these two highly regarded young seismologists here who share their earlier connection may be unusual, even for us. It's probably not coincidental that they are both exploring aspects of the basic physics of earthquakes, and we look forward to, and hope to learn very much from, their very promising future work.
Kīlauea Activity Update
Lava continues to erupt from the TEB vent, on Kīlauea's east rift zone, and flows through tubes to the ocean at Waikupanaha. A series of deflation-inflation cycles (DI events) over the past week disrupted the supply of lava through the tube system. As a result, surface flows on the pali have been largely absent over the past week, though a few small breakouts were reported.
Faint glow above the vent at Kīlauea's summit remains visible at night, and an incandescent hole is visible on the floor of the vent after dark in the Halema`uma`u Overlook webcam. Lava has not yet reappeared. Volcanic gas emissions remain elevated, resulting in high concentrations of sulfur dioxide downwind.
Three earthquakes beneath Hawai`i Island were reported felt this past week. A magnitude-1.8 earthquake occurred at 8:34 p.m., H.s.t., on Friday, August 14, 2009, and was located 7 km (4 miles) WNW of Pohakuloa at a depth of 16 km (10 miles). A magnitude-2.9 earthquake at 4:18 a.m., H.s.t., on Saturday, August 15, was located 5 km (3 miles) N of Ka`ena Point at a depth of 10 km (6 miles). A magnitude-2.4 earthquake at 4:29 p.m., H.s.t., on Sunday, August 16, was located 2 km (1.2 miles) ENE of Pu`ulena Crater at a depth of less than 1 km (0.6 miles).
Visit our Web site (http://hvo.wr.usgs.gov) for detailed Kīlauea and Mauna Loa activity updates, recent volcano photos, recent earthquakes, and more; call (808) 967-8862 for a Kīlauea activity summary; email questions to askHVO@usgs.gov.
Updated: October 2, 2009 (pnf)