1. Soil Formation

2. What is soil made of? Weathered rock Organic material (humus) Air
Soil has 4 components:
Weathered rock
Organic material (humus)
Air
Water

3. Soil is formed from weathered rock and organic material (HUMUS)
PARENT MATERIAL is what the soil forms from
When the parent material is the underlying bedrock of the area the soil is called RESIDUAL SOIL (residual = what is left behind when the bedrock weathers)
If the soil was formed in one place and carried elsewhere (by wind, water, glaciers, etc…) then the soil is called TRANSPORTED SOIL
MUCH OF THE SOIL IN NYS IS TRANSPORTED SOIL LEFT BEHIND BY GLACIERS!

4. Cross section of soil layers
Each layer is called a HORIZON
Horizon O/A = Topsoil (mostly Humus, some weathered rock)
Horizon B = Mostly weathered rock, some organic material (mineral rich zone)
Horizon C = Broken Bedrock
BEDROCK

5. HORIZON A
HORIZON B
HORIZON C

6. IT TAKES 100-400 YEARS FOR 1cm OF TOPSOIL TO FORM!!!!
Plants hold the soil together and prevent soil erosion

7. MOVEMENTS OF THE EARTH CAUSED BY THE FORCE OF GRAVITY
MASS MOVEMENTS
MOVEMENTS OF THE EARTH CAUSED BY THE FORCE OF GRAVITY

8. CREEP Very slow downward movement of soil
Only noticeable by the results of trees, fence posts, telephone poles, etc… that are tilted downhill

10. LANDSLIDE
RAPID mass movement of soil downhill (usually a very steep slope)
AVALANCHE – landslide made of Ice & Snow as well as Soil
SLUMP – small areas of land move downhill - especially along roadways that cut into the side of hills

16. MUDFLOW or LAHAR
Very fast & Dangerous movement of water saturated soil (MUD)

18. Even though rapid mass movement is more noticeable than slow mass movement, overall, more material is transported via creep than all others combined