1. 3/19/15

2.  Not All Rocks are the Same  “Hard” rocks (granite) weather slower than “softer” rocks (limestone)  Reason is based on minerals that make up rock type  Process of softer rock wearing away, leaving behind harder rock is known as differential weathering

3.  Differential Weathering at Work Devil’s Tower, Wyoming Believed to have looked like Currently looks like

4.  The Surface Area Effect  Weathering takes place on the outside surface of rocks  Larger surface area means more exposed surface  faster weathering  Bigger (volume) is not always better  One large rock (slow) vs Lots of smaller rocks (fast)

5.  The Climate Effect  Climate: average weather conditions of an area over a long period time  Climate can effect weathering through:  Temperature  Moisture  Elevation

6.  Temperature  Major factor in both types of weathering  MW: More freeze and thaw cycles  more ice wedging  NJ vs. Maine  CW: Lots of chemical reactions speed up in higher temperatures  Quicker break down of rock

7.  Moisture  Water can act as a MW agent and CW agent  MW: More rain  faster moving rivers  greater abrasion  CW: More moisture  more oxygen  greater oxidation  Florida vs Arizona

8.  Elevation  Elevation: how high a place is above sea level  Higher elevation (mountains)  exposure to more wind, rain, and ice  Low elevation (sea level)  exposure to ocean waves