Geology: Processes, Hazards, and Soils

1
Geology Processes, Hazards, and Soils
G. Tyler Millers Living in the Environment 13th
Edition Chapter 10
Dr. Richard Clements Chattanooga State Technical
Community College
2
Key Concepts

• Internal geologic processes

• External geologic processes

• Minerals, rocks, and the rock cycle

• Earthquakes and volcanoes

• Soil structure and formation

• Soil conservation

3
Geologic Processes

• Structure ofthe Earth

Fig. 10-2 p. 204
4
Features of the Crust
Fig. 10-3 p. 205
5
Internal EarthProcesses

• Plate tectonics

• Divergent boundary

• Convergent boundary

• Subduction zone

• Transform fault

• Ring of Fire

Refer to Fig. 10-5 p. 207
Fig. 10-6 p. 208
6
External Earth Processes

• Erosion

• Mechanical weathering

• Frost wedging

• Chemical weathering

Refer to Fig. 10-7 p. 209
7
Minerals and Rocks

• Mineral (diamond, bauxite)

Rock Types

• Igneous (granite, lava)

• Sedimentary (limestone, sandstone)

• Metamorphic (marble, slate)

8
The Rock Cycle
Heat, Pressure
External Processes
Internal Processes
Heat, Pressure
Igneous Rock Granite, Pumice, Basalt
Magma (Molten Rock)
Refer to Fig. 10-8 p. 210
9
Natural Hazards Earthquakes

• Features

• Magnitude

• Aftershocks

• Primary effects

• Secondary effects

Fig. 10-9 p. 210
10
Expected Earthquake Damage
Fig. 10-10 p. 211
11
Natural Hazards Volcanic Eruptions
Fig. 10-11 p. 211
See Introductory Essay p. 203
12
Soils Formation

• Soil horizons

• Soil profile

• Humus

Fig. 10-12 p. 212
13
Soil Properties

• Infiltration

• Leaching

• Porosity/permeability

• Texture

• Structure

• pH

14
Table 10-1 p. 216
Texture Nutrient Infiltration Water-Holding Aerati
on Tilth Capacity Capacity Clay Good Poor Good
Poor Poor Silt Medium Medium Medium Medium Medium
Sand Poor Good Poor Good Good Loam
Medium Medium Medium Medium Medium
Refer to Fig. 10-15 p. 215
15
Soils Erosion

• Sheet erosion

• Rill erosion

• Gully erosion

See Fig. 10-18 p. 217
16
Global Soil Erosion
Fig. 10-19 p. 218
17
Soils Degradation

• Desertification

• Salinization

• Waterlogging

Fig. 10-22 p. 221
18
Solutions Soil Conservation

• Conventional-tillage

• Conservation tillage

• Cropping methods

• Windbreaks

Refer to Fig. 10-26 p. 224

• Land Classification

19
Soil Restoration

• Organic fertilizer

• Animal manure

• Green manure

• Compost

• Crop rotation

• Commercial inorganic fertilizer