Tuesday, March 29, 2011

Igneous Rock Experiment

Spark did an experiment to see how Igneous rocks are formed.  Igneous rocks are formed when magma cools and changes into solid rock.  There are two kinds of Igneous rocks, extrusive and intrusive.  Extrusive rocks are formed when a volcano erupts and the lava hardens on the surface of the earth.  Intrusive rocks are formed on the inside of the earth.  Intrusive rocks move to the top of the earth through erosion or when the earth shifts.  

To do the experiment Spark used a cup of hot water, a spoon, a square of milk chocolate, a cup of cold water and a saucer.


First the spoon needed to be heated up so he put it in the cup of hot water for about a minute.


The milk chocolate represents the rock because it melts at a rather low temperature.


He put the "rock" on the spoon and pushed it around until it got good and melty.  This was to show how the rock would have melted from either a volcano or from the temperature of the earth at 25-37  miles below ground.


Next he put the chocolate in a cup of cold water.  This didn't make his rock hard enough so he put it in the freezer for a few minutes to get the rock like it would be if it was hardened either by flowing out of a volcano or rising higher than the intense heat in the earth.  Lastly, he scraped the rock off the spoon to show how the rocks would have looked.  A little non stick spray may have made this part easier because it wouldn't come off in one piece.

No comments: