Higher earthquake risk for eastern US
19 July BBC
A new US geological survey indicates that some parts of the US are at
an increased risk of earthquakes, especially along the east coast.
New seismic hazard maps updated for the first time since 2008 show
highest risk west but also increased risk east.The eastern US has the
potential for larger and more damaging earthquakes than considered in
previous maps and assessments," the report states.The East Coast
experienced one of its largest quakes for 100 years in 2011.The 5.8
magnitude quake was centred on rural Virginia but was felt by hundreds
of thousands of people, including in Washington DC.Parts of states
including Alaska, Hawaii, Oregon and California remain at the highest
risk of seismic activity.
Major fault lines exist along the entire US West Coast, as well as in
the Midwest near Illinois and Missouri.While all states have some
potential for earthquakes, 42 of the 50 states have a reasonable chance
of experiencing damaging ground shaking from an earthquake in 50 years,"
the new report finds.
"The hazard is especially high along the West Coast, intermountain
west, and in several active regions of the central and eastern US." The
16 states at highest risk are: Alaska, Arkansas, California, Hawaii,
Idaho, Illinois, Kentucky, Missouri, Montana, Nevada, Oregon, South
Carolina, Tennessee, Utah, Washington, and Wyoming.Meanwhile, several
states saw their risk of seismic activity lower, including Texas,
Oregon, Utah and New York.
Earthquakes caused by fracking utilising a mixture of water, sand and
chemicals pumped underground at high pressure to crack open sedimentary
rocks and release the fuels within were not included in the analysis.
Several hundred earthquakes have hit Oklahoma so far this year, with
fracking named a primary culprit, although the impact of fracking on
earthquake risks is disputed. |