Moment of Science: Earthquakes

Earthquakes

The Earth is always moving- even the ground beneath your feet!  Luckily for us, geologists estimate the ground moves as fast as your hair grows, which is why you don’t really feel it. But when you do feel the ground shaking we call that an earthquake.

The Earth is made up of layers. What we commonly think of as the ground is the crust of the Earth – the outermost layer made up of solid rocky material. However, the crust is not one solid piece, but instead it’s broken into several pieces called tectonic plates. These puzzle-like pieces can push against each other, pull away from each other, slide across from each other, or even get stuck.

Sometimes two different plates can’t get past each other, but they keep trying to move. Over time, each movement causes pressure to build up along the fault, the area where two plates meet. Eventually, when the fault can’t hold any more pressure or stress, the plates will move – causing an earthquake.

Earthquakes are natural events that happen inside the Earth, so they have nothing to do with weather. Geologists do not have the science or technology to predict earthquakes, but there are some early warning systems around the world – alerting folks that an earthquake has struck and is on its way to them. In an earthquake-prone region like Southern California, it’s always a good idea to know what to do in case of an earthquake. Join the Discovery Cube and millions of others around the world in an annual earthquake readiness drill called “The Great Shakeout” on October 19, 2017 at 10:19 am.

Materials:

Tower

  • Small Marshmallows (any color)
  • Large Marshmallows
  • Round Toothpicks
  • Regular Wooden Ruler
  • Masking Tape Roll
  • Long Rubber Bands
  • Foam Boards or Binder Covers
  • Whiffle or Rubber Balls
  • Sheet of Bubble Wrap- 8 ½ x 11
  • Gallon Size Zip Bag- (fill with whiffle balls)

 Directions:

Step 1: Use toothpicks and marshmallows to build an earthquake safe tower at least 12 inches tall.

Step 2:  Place a sheet of bubble wrap on top of one of the foam boards or binder covers.

Step 3: Place a bag filled with a few whiffle or rubber balls on top of the second foam board. Make sure the bag stays closed.

Step 4: Use masking tape to secure a ruler on the second foam board.

Step 5: Place a second foam board over the bag of whiffle balls with the ruler facing up.

Step 6: Place a rubber band at each end of the foam boards to keep everything together.

Step 7: Test the strength of your tower using your shake table. Make sure to hold the bottom of the shake table during the testing.