Looking to the east you can see the weathering that is taking place in the sandstone. Use what you see to answer the following questions.
1-Looking at the different layers, do the weaker layers seem to be the same thickness as each other? Or do they appear to vary.
2-Looking closely at the weathered layer and the non weathered layer do you see any differences or similarities in them?
3-Would you guess the weathering is Physical other chemically related? explain?
4-Can you see anything that appears to be common in the more eroded vs the less eroded layers?
Weathering
What a rock is made of effects the weathering a great deal. Quartz, basalt, and other very hard rocks weather very slowly. Where rocks that are chemically bonded together (sandstones and limestones) will erode much quicker. If you have two types of rocks together, the rocks that are harder will be left behind while the others remain, or break free.
How a rock is exposed to the weather, and how much of a softer surface is exposed can effect the the weathering greatly. A rock under a waterfall, fast running stream, or coastal cliff, will erode faster than a rock that is in a desert environment.
Chemical Weathering
Chemical weathering is the process of erosion that is based on chemicals breaking down the rock, or some particles of the rock. Acid rain is one of the best known chemical weathering processes.
In chemical weathering rain that contains some acid will fall on rocks that break down under the acid. This is most common in limestones. However many caves are worn by the acids seeping through them.
Another process is rust. Iron and other metals can oxidize (rust) and slowly erode away.
Water is another type of chemical erosion. This can be from rain or from water that is washing some of the material away, or causing some of the material to dissolve.
Physical Weathering
Block or Granular. This is a block, cobble, or stone that may break off of a cliff or another rock.
Wind. Wind can carry material that will erode other stones in the area.
Frost and freezing. This is a process where the freezing of the water may break off a number of particles. This can also get between larger stones and break them apart.
Exfoliation. This happens in very warm environments. Those that reach over 100 degrees. The rock can start to break up as the heat expands the rock at a different rates
Salt Weathering. Similar to frost, but salt crystals form rather than ice.
At this location
If you look to the east you can see the sandstone hills. This was a flood plain at one time. The sediments that were deposited varied on the time of year, and the flood conditions. So we see different compositions of the different layers.causing them to wear at different rates. The two photos Below are by NASA from the Curiosity Rover.
On Mars
Not only does this happen on earth, but on Mars. A study by geologists
