Mizzou Engineering digging further into earthquakes
Mizzou Engineering researchers have begun digging more deeply into what triggers earthquakes, thanks to a powerful new device that simulates the enormous forces bearing down on rocks about a kilometer below the ocean floor.
Engineering’s geotechnical group in mid-April installed a $16,800 high-pressure soil compression test device, jointly financed by a $4,000 donation from Kansas City, Mo.-based Burns & McDonnell Inc. and MU’s civil and environmental engineering and geological sciences departments. The new device can place as much as 10,000 pounds of force on a rock sample, compared to the 2,000-pound capacity of the group’s other devices, said William J. Likos, a civil and environmental engineering assistant professor who worked to obtain the equipment.
“That’s sufficient to simulate the pressures associated with about one kilometer below the sea floor,” Likos said.
Those types of enormous pressures shaped the samples Mizzou researchers collected last year during a research drilling expedition organized by the Integrated Ocean Drilling Program (IODP), a marine research organization including the United States, Japan, Europe, China and South Korea.
Likos and MU geology Professor Michael Underwood were among eight American scientists who joined the IODP’s November 2007 expedition #315 to drill into and sample the ocean floor in a well-known fault system in the Nankai Trough, off Japan’s coastline. The fault system periodically produces devastating earthquakes and tsunamis, most recently during the 1940s.
With the high-pressure soil compression test device, MU engineers and geologists can analyze how deep-sea stresses and changes in sediment and rock properties help produce earthquakes.
“It’s a very complex system, and if we can understand the stresses in this complex system, then we can develop a better understanding of earthquakes,” Likos said.
That understanding of deep material properties along active faults may well help geologists figure out earthquakes closer to home, such as the quake that shook Illinois and its neighboring states on May 1, Underwood said.