Geology Reference
In-Depth Information
Exposed, unweathered parent material -
consolidated bedrock
or
unconsolidated material
(e.g. glacial drift; alluvium)
Physical weathering of parent material -
decrease of particle size, but little or no chemical alteration
Chemical / biological weathering of parent material -
formation of secondary minerals
Soil formation
-
incorporation of organic matter into surface layers
soil forming processes in subsoil -weathering, leaching, etc.
slowly weathering parent material
Figure 1 Weathering sequence in soil
Atmosphere
Biosphere
Biomass
Humus
Soil air
Soil
Rocks and
minerals
Soil water
Lithosphere
Hydrosphere
Figure 2 Components of soil
