CSES 2040-EXAM 1 UPDATED ACTUAL Questions and CORRECT Answers
The unconsolidated mineral or organic material on the immediate surface of the
Earth that serves as a natural medium for the growth of land plants.
Soil is a natural body comprised of solids (minerals and organic matter), liquid, and
What is SOIL? gases that occurs on the land surface, occupies space, and is characterized by one
or both of the following: horizons, or layers, that are distinguishable from the initial
material as a result of additions, losses, transfers, and transformations of energy and
matter or the ability to support rooted plants in a natural environment.
Homogeneous inorganic compounds - have a definite chemical formula
Minerals
• Two main groups: Primary and Secondary minerals
Primary minerals Formed as molten lava cools and solidifies, not chemically altered by weathering
Secondary minerals recrystallization and/or alteration of primary minerals
weather less rapidly
Primary Minerals - light colored • Quartz
aluminosilicates examples • Feldspars
• Muscovite mica
weather more rapidly
• Biotite mica
Primary Minerals - dark colored ferro-
• Hornblende
magnesium minerals examples
• Dioside
• olivine
Heavy weather and low pH
1. Al & Fe (metal) oxides and hydroxides (sesquioxides) Geothite - FeOOH
Hematite - Fe2O3
Gibbsite - Al(OH)3 These are very stable soil minerals, dominate in old soils.
Secondary Minerals 2. Aluminosilicate clay minerals - very common and complex (we will spend more
time on these later)
3. Salts
calcite (lime)- CaCO3
gypsum - CaSO4
, Geothite FeOOH
Hematite Fe2O3
Gibbsite Al(OH)3
calcite (lime) CaCO3
gypsum CaSO4
• Igneous
Rocks - Mixtures of Minerals • Sedimentary
• Metamorphic
• Formed when molten lava cools
• Example is granite, which contains the primary minerals quartz and feldspar
Igneous Rocks
• Another example is basalt, which contains the minerals hornblende, augite and
biotite
Sedimentary deposition and re-cementation of weathering products from other rocks.
Metamorphic igneous or sedimentary rocks transformed by high heat or pressure.
Softer:
Shale
Sedimentary examples
Sandstone
Limestone
Harder:
Slate
Metamorphic examples
Quartzite
Marble
Disaggregation of fragmentation of rocks. No change in composition (chemical
alteration.)
Freeze-thaw cycles
Physical weathering
Root impacts
Pressure release
Abrasion
Change in the chemical composition. These are reactions with minerals, water, and
air.
Hydrolysis
Dissolution
Hydration
Carbonation
Chemical weathering
Oxidation-reduction
• Alters the composition of minerals
• Converts primary minerals to secondary and secondary to other secondary
• Most rapid in warm temperatures, high precipitation - such as Alabama
• Water is REQUIRED
• Five different chemical weathering processes
Process with living things, and so can include physical or chemical processes.
Worms
Biological weathering Burrowing animals
Microbial activity
Moss Lichen
The unconsolidated mineral or organic material on the immediate surface of the
Earth that serves as a natural medium for the growth of land plants.
Soil is a natural body comprised of solids (minerals and organic matter), liquid, and
What is SOIL? gases that occurs on the land surface, occupies space, and is characterized by one
or both of the following: horizons, or layers, that are distinguishable from the initial
material as a result of additions, losses, transfers, and transformations of energy and
matter or the ability to support rooted plants in a natural environment.
Homogeneous inorganic compounds - have a definite chemical formula
Minerals
• Two main groups: Primary and Secondary minerals
Primary minerals Formed as molten lava cools and solidifies, not chemically altered by weathering
Secondary minerals recrystallization and/or alteration of primary minerals
weather less rapidly
Primary Minerals - light colored • Quartz
aluminosilicates examples • Feldspars
• Muscovite mica
weather more rapidly
• Biotite mica
Primary Minerals - dark colored ferro-
• Hornblende
magnesium minerals examples
• Dioside
• olivine
Heavy weather and low pH
1. Al & Fe (metal) oxides and hydroxides (sesquioxides) Geothite - FeOOH
Hematite - Fe2O3
Gibbsite - Al(OH)3 These are very stable soil minerals, dominate in old soils.
Secondary Minerals 2. Aluminosilicate clay minerals - very common and complex (we will spend more
time on these later)
3. Salts
calcite (lime)- CaCO3
gypsum - CaSO4
, Geothite FeOOH
Hematite Fe2O3
Gibbsite Al(OH)3
calcite (lime) CaCO3
gypsum CaSO4
• Igneous
Rocks - Mixtures of Minerals • Sedimentary
• Metamorphic
• Formed when molten lava cools
• Example is granite, which contains the primary minerals quartz and feldspar
Igneous Rocks
• Another example is basalt, which contains the minerals hornblende, augite and
biotite
Sedimentary deposition and re-cementation of weathering products from other rocks.
Metamorphic igneous or sedimentary rocks transformed by high heat or pressure.
Softer:
Shale
Sedimentary examples
Sandstone
Limestone
Harder:
Slate
Metamorphic examples
Quartzite
Marble
Disaggregation of fragmentation of rocks. No change in composition (chemical
alteration.)
Freeze-thaw cycles
Physical weathering
Root impacts
Pressure release
Abrasion
Change in the chemical composition. These are reactions with minerals, water, and
air.
Hydrolysis
Dissolution
Hydration
Carbonation
Chemical weathering
Oxidation-reduction
• Alters the composition of minerals
• Converts primary minerals to secondary and secondary to other secondary
• Most rapid in warm temperatures, high precipitation - such as Alabama
• Water is REQUIRED
• Five different chemical weathering processes
Process with living things, and so can include physical or chemical processes.
Worms
Biological weathering Burrowing animals
Microbial activity
Moss Lichen
