The Times West Virginian

Community News Network

May 8, 2013

When the earth moves under our feet

One of the most breath-taking geologic events is a major earthquake. In just a few moments, shaking of the Earth can result in billions of dollars of damage and thousands of lives lost.

Many earthquakes are related to the movement of tectonic plates, the large chunks of the Earth’s outer surface that move with respect to each other. Plates are “born” in places like Iceland, where magma comes up from below and creates oceanic plate material. Plates “die” where one plate dives beneath another and ultimately is pulled and pushed down so deeply into the Earth it melts away. Plates vary a bit in how fast they move, but about an inch or two a year is not uncommon.

One example regarding tectonic movement is in the Pacific Northwest. The Cascadia subduction zone is the area where the Juan de Fuca plate is diving under the North American plate. The movement generates major earthquakes from time to time. The most recent mega-quake occurred in 1700. Geologists think the region is about due for another similar event.

Recently I was reading in Science News about new information regarding earthquakes and plate movement. In the Cascadia region something called “slow slip” happens about every 15 months. Slow slip occurs when the rocks on either side of a major fault move about the same amount as in a major earthquake, but they do so over weeks to months rather than almost instantaneously.  

The evidence for slow slip was documented first for Cascadia in the bedrock of Vancouver Island, British Columbia. Now that geologists know what to look for, slow slip events have been identified the world around. In Japan, some slow slip events have been documented that occur about each three to five years and last a few months, while others occur more frequently.

Text Only
Community News Network
  • Arizona's prolonged lethal injection is fourth in U.S. this year

    Arizona's execution of double-murderer Joseph Wood marked the fourth time this year that a state failed to dispatch a convict efficiently, according to the Constitution Project, a bipartisan legal group.3

    July 24, 2014

  • Police Brutality screen shot. Technology plays key part in battling police brutality (VIDEO)

    Allegations of police brutality are nothing new -- as long as there has been law enforcement, citizens have registered claims that some officers cross the line. But in the last few years, the claims of excessive force are being corroborated with new technology from cell phone cameras, police dash-cams and surveillance videos. 

    July 24, 2014 1 Photo

  • Facebook continues moneymaking trend

    Facebook seems to have figured out - for now at least - the holy grail for all media right now: how to make money selling mobile ads.

    July 24, 2014

  • Has the ipad lost its swag?

    July 24, 2014

  • Almost half of America's obese youth don't know they're obese

    The good news is that after decades of furious growth, obesity rates finally seem to be leveling off in the U.S.. The bad news is that America's youth still appear to be dangerously unaware of the problem.

    July 23, 2014

  • 072214 Diamond Llama 1.jpg Llama on the loose corralled in Missouri town

    A llama on the lam cruised Main Street Tuesday before it mistook a resident’s fenced backyard for a place to grab a meal and freshen up.

    July 22, 2014 2 Photos

  • An oncologist uses scorpion venom to locate cancer cells

    Olson, a pediatric oncologist and research scientist in Seattle, has developed a compound he calls Tumor Paint. When injected into a cancer patient, it seems to light up all the malignant cells so surgeons can easily locate and excise them.

    July 22, 2014

  • Screen Shot 2014-07-22 at 2.00.42 PM.png VIDEO: Train collides with semi truck carrying lighter fluid

    A truck driver from Washington is fortunate to be alive after driving his semi onto a set of tracks near Somerset, Ky., and being struck by a locomotive, which ignited his load of charcoal lighter fluid.

    July 22, 2014 1 Photo

  • mama.jpg What we get wrong about millennials living at home

    If the media is to be believed, America is facing a major crisis. "Kids," some age 25, 26, or even 30 years old, are living out of their childhood bedrooms and basements at alarmingly high numbers. The hand-wringing overlooks one problem: It's all overblown.

    July 22, 2014 1 Photo

  • Hospitals let patients schedule ER visits

    Three times within a week, 34-year-old Michael Granillo went to the emergency room at Northridge Hospital Medical Center in Los Angeles because of intense back pain. Each time, Granillo, who didn't have insurance, stayed for less than an hour before leaving without being seen by a doctor.

    July 21, 2014

House Ads
Featured Ads