Federal Study of East Coast Earthquake Had to Move Fast
James R. Martin II, an earthquake expert was tasked August 26 with leading an investigative team of U.S. scientists and engineers to document aftereffects of the August 23 East Coast earthquake centered near Mineral, Va. His investigation team had to move fast to take samples, create maps and photograph regional damage to subsurface and infrastructure locations. Hurricane Irene made landfall August 27.
The August 23 earthquake measured 5.8 on the Richter magnitude scale. It was felt across not only Virginia, but as far south as Georgia and as far north as New Hampshire, according to a myriad of news reports and social media status updates. Structural damage was relatively light.
“The most pressing issue has been collecting perishable data ahead of Hurricane Irene,” Martin said August 30, a week after the earthquake rattled the East Coast and three days after Hurricane Irene soaked it with flooding rains, followed up by high winds. “In this effort, we have successfully leveraged many geotechnical engineering firms and relevant contacts throughout the region.”
A professor of civil and environmental engineering at Virginia Tech, Martin’s team comprises members of the Geotechnical Extreme Events Reconnaissance Association. It is coordinating investigation efforts with key agencies and organizations such as the Earthquake Engineering Research Institute, U.S. Geographical Survey, Virginia’s state Geological Survey, and the departments of transportation in Virginia, Maryland and Washington, D.C., among others.
“We feel we documented the most important findings, although minor features that may have been present along some rivers and stream may have been lost due to heavy rains and subsequent rises in rivers and streams,” he said.
Martin was asked last week by the National Science Foundation to coordinate the investigation of the earthquake’s geotechnical impacts. Efforts included a myriad of tools and methods: Field observations, detailed mapping, and surveying of damaged areas, among others.
“Beyond technical findings, the event can also teach us much about the need for greater preparedness for and better awareness of eastern U.S. earthquake hazards,” he said.
Damage from the August 23 event was relatively light. Two Washington, D.C., landmarks suffered some effects: The Washington Monument and the National Cathedral. Martin said additional damage reports came in from as far away as New York City, some 320 north on Interstate 95 from Mineral, Va. The earthquake also triggered the shutdown of the nuclear reactors at the North Anna Power Plant located near the epicenter, in Louisa County, Va.
“While significant geotechnical failures are not anticipated, it is nonetheless important to carefully document regional performance,” Martin said. “Particular focus is upon river and stream deposits typically the most vulnerable, waterfront structures, bridges, dams and embankments, earth-retaining systems, monuments and institutions that were damaged, and critical facilities such as major airports and the power plant. It will also be important to study how soil and geologic conditions may have influenced selective damage patterns in the epicentral region and more distant locations such as Washington, D.C., and New York.”
Work to collect evidence from the earthquake is continuing post-Hurricane Irene. Martin and his team have an open budget for now, with focus on preparing a preliminary report for the National Science Foundation within two or so weeks. A more detail report will follow in the next few months. After field investigations are complete, observations, findings and images will be posted on the Geotechnical Extreme Events Reconnaissance Association website, with photo links visible via Google Earth.