The Pryor Times

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 | Photo Reprints
Community News Network
  • Why a see-through mouse is a big deal for scientists

    A group of Caltech researchers announced in Cell Thursday their success in making an entire organism transparent. Unfortunately, this isn't any kind of "Invisible Man" scenario: The organism in question is a mouse, and the mouse in question is quite dead.

    July 31, 2014

  • Screen Shot 2014-07-31 at 2.12.55 PM.png VIDEO: Five-year-old doesn't want her brother to grow up

    Sadie, an adorable 5-year-old from Phoenix, wants her brother to stay young forever, so much so that her emotional reaction to the thought of him getting older has drawn more than 10 million views on YouTube.

    July 31, 2014 1 Photo

  • lockport-police.jpg Police department turns to Facebook for guidance on use of 'negro'

    What seems to be a data entry mistake by a small town police department in western New York has turned into a social media firestorm centered around the word "negro" and whether it's acceptable to use in modern society.

    July 31, 2014 3 Photos

  • The virtues of lying

    Two computational scientists set out recently to simulate the effects of lying in a virtual human population. Their results, published in the Proceedings of the Royal Society B, show that lying is essential for the growth of a cohesive social network.

    July 31, 2014

  • Sunburn isn't the only sign of summer that can leave you itchy and blistered

    You've got a rash. You quickly rule out the usual suspects: You haven't been gardening or hiking or even picnicking, so it's probably not a plant irritant such as poison ivy or wild parsnip; likewise, it's probably not chiggers or ticks carrying Lyme disease; and you haven't been swimming in a pond, which can harbor the parasite that causes swimmer's itch.

    July 30, 2014

  • Survey results in legislation to battle sexual assault on campus

    Missouri U.S. Sen. Claire McCaskill joined a bipartisan group of senators Wednesday to announce legislation that aims to reduce the number of sexual assaults on college campuses.

    July 30, 2014

  • An alarming threat to airlines that no one's talking about

    It's been an abysmal year for the flying public. Planes have crashed in bad weather, disappeared over the Indian Ocean and tragically crossed paths with anti-aircraft missiles over Ukraine.

    July 30, 2014

  • Sharknado.jpg Sharknado 2 set to attack viewers tonight

    In the face of another "Sharknado" TV movie (the even-more-inane "Sharknado 2: The Second One," premiering Wednesday night on Syfy), there isn't much for a critic to say except to echo what the characters themselves so frequently scream when confronted by a great white shark spinning toward them in a funnel cloud:
    "LOOK OUT!!"

    July 30, 2014 1 Photo

  • 20140729-AMX-GIVHAN292.jpg Spanx stretches into new territory with jeans, but promised magic is elusive

    The Spanx empire of stomach-flattening, thigh-slimming, jiggle-reducing foundation garments has expanded to include what the brand promises is the mother of all body-shaping miracles: Spanx jeans.

    July 29, 2014 1 Photo

  • Medical marijuana opponents' most powerful argument is at odds with a mountain of research

    Opponents of marijuana legalization are rapidly losing the battle for hearts and minds. Simply put, the public understands that however you measure the consequences of marijuana use, the drug is significantly less harmful to users and society than tobacco or alcohol.

    July 29, 2014