Mount Hood Hides Secret Earthquake Fault

Mount Hood, Oregon. CREDIT: NASA Earth Observatory. View full size image

Mount Hood, the tallest mountain in Oregon, has a secret, scientists revealed. Covered by trees and plants is an earthquake fault that stretches for miles from the iconic mountain.

The fault appears to have been recently active, and could be an earthquake threat today, reported the Portland Oregonian. Scientists said the last time the fault ruptured, possibly as a magnitude 6 or 7 earthquake, the ground ripped six feet (1.8 meters) apart.

The fault was discovered by scientists flying over Mt. Hood using lasers to scan the terrain. The fault is about 20 miles (32.2 kilometers) long and stretches from the northern flank of Mount Hood to the Columbia River.

Earthquakes are not a foreign concept to Oregonians. The nearby Cascadia Subduction Zone could unleash a magnitude 9 earthquake, similar to the size of the deadly earthquake that ruptured in Japan. Scientists aren't sure how big of an earthquake could rupture from the new Mount Hood fault. The research team, from the Oregon Department of Geology and Mineral Industries, are now working to estimate the threat that the fault poses to nearby communities.

"We don't know where all the seismic faults exist in Oregon. We don't know how often they cause earthquakes," Oregon State University engineer Michael Olsen, told the Oregonian. "That leads to a lot of uncertainty when we try to design buildings," he says, that are sufficiently resistant to earthquake damage.

In the coming weeks, scientists will dig a trench above the fault line so they can examine the soil for clues about past earthquakes. Looking at how the gravel and dirt has settled after past quakes could tell scientists about the size of previous quakes along the fault.

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