the speed rocks weather depends on a few factors… check em out
TRANSCRIPT
The speed rocks weather depends on a few factors… check em out
Granite:
Igneous & Resistant
Limestone:
Sedimentary &
Non-resistant
1. Mineral Composition: The harder the minerals that make up a rocks composition, the slower the rate of weathering
2. Rock Type: Some rocks are more resistant to weathering based on how they formed
- Igneous and Metamorphic Rocks have minerals strongly bonded together and are resistant
- Sedimentary Rocks are less resistant rocks b/c of weak bonds holding them together
4. Climate
a. Cold and Humid: Physical weathering is dominate at high latitudes & altitudes
b. Hot and Humid: Chemical weathering is dominate at low latitudes & altitudes.
Hot Humid Climates favor:
1. Chemical weathering - oxidation
2. Plant Action
“Lichens” live off of minerals in the rocks and produce more soil than anything else on Earth.
Chemical weathering occurs when lichens secret acid which breaks down rock.
Physical weathering is dominate at high latitudes & altitudes.
The process leads to smaller and smaller rock fragments and over time develops rock into soil
Products of Weathering:
Weathering produces sediments and soils
2. Soil Types: a. Residual: Soils formed from the local bedrock and have the same mineral composition.
b. Transported: Soil that has been moved & the sediments do not have the same composition as the local rock
Soil Horizons:
A. Top layer rich in organics (Humus) & minerals
B. Sediments found here have minerals that were dissolved from above, & infiltrated when it rained
C. Mostly particles from the local bedrock
Soil development: Soils are the result of weathering and biological activity over long periods of time.
Stage 1: Mostly un-weathered bedrock
Stage 2: Development of top soil by biologic activity
Stage 3: Thick and well developed
soil horizons (A,B,C)
- Soils are considered non-renewable resources in most areas since only 1 inch is made every 100 years.
- Different climates will produce different soil types at different rates
