Patrick Kodman Essay

Submitted By lkjgio
Words: 665
Pages: 3

Patrick Kodman
Mr. Headley
9A
5/11/15

Internal Forces vs. External Forces of the Earth

The earth’s surface is constantly changing due to two major forces that shape its formation. Internal forces such as earthquakes and volcanoes push up rock on the earth’s surface and eternal forces that you see outside of the earth like wind and water breakdown rock surfaces. Since the flood these forces have shaped what the earth is today and created mountains and other land forms.
Internal forces like earthquakes and volcanoes are forces that work deep within the earth. These forces aren’t perfectly understood by scientists. Using sonar, a method that uses sound waves to create a picture, scientists know that these forces gather along lines on the earth’s surface even under the ocean. Scientist also have evidence that the earth is broken into in to plates. These plates are broken pieces of the earth’s crust. They believe these plates push and pull into each other releasing energy. This energy is the cause of earthquakes and volcanoes. This theory is called the Plate Tectonic Theory. These plates are still moving today. Some scientist believe the earth first broke into pieces during the Flood.
The deep lines in the earth’s surface are called fault lines. They occur when pieces of land move in different directions usually only a few inches but still cause lots of damage. Earthquakes and volcanoes are scattered across the earth’s surface clustered on these fault lines. Using sonar technology scientist can see these fault lines as they continue under the ocean.
There are two types of fault lines called thrust faults and strike-slip faults. Thrust faults are caused when lower positioned rocks push up and over higher rocks. It is often noticed because the older rocks are above the younger rock. (Wikipedia, Thrust Faults) Strike-slip faults are vertical fractures where the blocks have mostly moved horizontally. If the block moves to the right, the slip style is called a right lateral; if the block moves to the left, it is called a left lateral. (Earthquakes.usgs.gov)
Another type of tectonic movement is called folding. It happens when the earth bends up in the middle because of forces pushing on opposite sides. This process formed many of the earth’s mountains. Active volcanic forces can also build mountains when lava from the volcanoes harden.
As internal forces within the earth’s surface build landforms, external forces called weathering and erosion work to wear them away. Rock is constantly changing due to weathering and erosion. Weathering is the breakdown of rocks due to temperature changes, water and plant roots. The top layer…