Seismology

  • What Was That Shaking?

    What Was That Shaking?
    The first person to study earthquakes was Massachusetts Governor John Winthrop, who's often referred to as the "Father of Seismology."
  • The Birth Of An Idea

    The Birth Of An Idea
    Scottish geologist David Milne suggested the idea of a machine that could measure seismic activity.
  • The Seismometer

    The Seismometer
    It was David Milne who coined the word "seismometer" to describe an instrument designed by James David Forbes that responds to ground noises and shaking.
  • First Time Recording Seismograph

    First Time Recording Seismograph
    The first time-recording seismograph was built in Italy, this device was used to measure the time between each seismic wave.
  • Mallet's Scientific Theories

    Mallet's Scientific Theories
    Robert Mallet, an engineer from Ireland, studied and developed theories about earthquakes. His original thought was that an earthquake moved outward from a central focal point.
  • Fault Lines

    Fault Lines
    American geologist Karl Gilbert discovered that earthquakes occur near fault lines.
  • Seismology Goes International

    Horizontal pendulums, used as a seismograph, recorded an earthquake in Japan from Germany.
  • First North American Seismograph

    First North American Seismograph
    The first seismograph in North America is installed at Lick Observatory near San Jose, California.
  • The Mercalli Intensity Scale

    The Mercalli Intensity Scale
    A seismologist named Giuseppe Mercalli created a device to measure the intensity or likelihood of damage that may be caused by an earthquake.
  • The Moho Boundary

    The Moho Boundary
    The boundary between the Earth's crust and the mantle. It is defined by the distinct change in velocity of seismological waves as they pass through changing densities of rock.
  • The Richter Scale

    The Richter Scale
    Charles Richter makes the Richter Scale to determine the magnitude of earthquakes using numerical values.