TULSA, Okla. (AP) — Experts are looking at how Oklahoma’s seismic activity impacts critical infrastructure as frequent, low-level earthquake swarms continue to pop off throughout the state.
Oklahoma had experienced 80 earthquakes of magnitude 3.0 or greater this year through Thursday morning, the Tulsa World reported . The state’s peak year was 2015, with just over 900 quakes of magnitude 3.0 or greater, according to the Oklahoma Geological Survey.
Soil, concrete and steel structures are “susceptible to fatigue and other unique failure modes” under seismic conditions that weren’t considered during design, according to an article this month in Leading Edge, a publication by the Society of Exploration Geophysicists.
“The long-term, low-level shaking associated with repeated minor to moderate magnitude earthquakes exposes infrastructure to possible failure modes not normally considered in design,” the article said.
The Tulsa-based society is hosting a forum in August.
“I know that it is really a huge issue that we are facing,” said Dwain Butler, the article’s lead author. “We tend to take the infrastructure that we have around us, that we depend on, for granted.”
Butler said a single, small earthquake won’t affect critical infrastructure like bridges, dams, oil pipelines and water treatment plants, but a structure, over time, can begin fatiguing and cracking, which allow rusting and small separations between concrete joints.
Scientists are worried especially about Cushing, an oil hub in Oklahoma with 300 storage tanks. Cushing’s many pipelines intersect and cross, significantly increasing the risk of a leak via long-term fatigue from the earthquakes, Butler said.
“Generally it may be relatively innocuous, because if you find it quickly you can repair it quickly,” he said. “But it’s still a risk.”
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Information from: Tulsa World, http://www.tulsaworld.com