PHYSICAL CHANGE OVER TIME PROJECT 04 LESSON 04

SOME WAYS PHYSICAL ENVIRONMENTS CHANGE Over time places change. There are processes that slowly change the physical characteristics of locations. 1. Wind Erosion 2. Water Erosion 3. Tectonic Plates 4. Deposition

WIND EROSION Wind erosion is when soil, sand, or rocks are moved by the wind, usually downhill, and away from their original location. It is sometimes referred to as the aeolian process. Excessive erosion leads to loss of soil, ecosystem damage, and a buildup of sediments in water sources. Building terraces and planting trees can help reduce erosion. The image shows a rock formation slowly eroded by wind. © Copyright Espresso Addict and licensed for reuse under CC BY-SA 2.0

WATER EROSION Water erosion is similar to wind erosion except, of course, it is caused by water. There are many ways that water can erode landforms. Some ways are through rain, rivers and streams, coastal erosion, glaciers, floods, and freezing and thawing. Image shows a cliff and road way weakened by water erosion This image is in the public domain

TECTONIC PLATES There are about twelve plates that make up the Earth’s surface. These tectonic plates have moved around on the Earth's surface through much of geologic time. The edges of the plates are marked by concentrations of earthquakes and volcanoes. Collisions of plates can produce mountains like the Himalayas, the tallest range in the world. Tectonic plates move at very slow rates of a few centimeters per year, slower than the rate at which fingernails grow. © Copyright Christian Bickel: fingalo and licensed for reuse under CC BY-SA 2.0 The image is from Þingvellir National Park in Iceland. It is located on the Mid-Atlantic Ridge between two tectonic plates. The faults and fissures are made by the rifting of the Earth’s crust.

DEPOSITION Deposition is when sediment is dropped or deposited in a new location. This occurs when there are changes in the speed of moving water, dropping sediment to pile up at the bottom of the water. This image is in the public domain The image on the left shows a small river moving sediment and depositing to build up in other locations.