Unit 3 Rocks, Soil, Erosion and Mass Movements

Unit 3 Rocks, Soil, Erosion and Mass Movements Including the Geological History of North Carolina!

Classification of Rock Most rocks have a number of minerals in common. Rocks are grouped on the basis of their physical and chemical properties, but most importantly, their origin. 1. Sedimentary Rocks Most form under water. Layering (“stratification”) will indicate this.

Classification of Rock Most rocks have a number of minerals in common. Rocks are grouped on the basis of their physical and chemical properties, but most importantly, their origin. 1. Sedimentary Rocks Most form under water. Layering (“stratification”) will indicate this. Sedimentary rocks are classified according to the way they were formed

Classification of Rock Most rocks have a number of minerals in common. Rocks are grouped on the basis of their physical and chemical properties, but most importantly, their origin. 1. Sedimentary Rocks Most form under water. Layering (“stratification”) will indicate this. Sedimentary rocks are classified according to the way they were formed and what was deposited:

Classification of Rock Most rocks have a number of minerals in common. Rocks are grouped on the basis of their physical and chemical properties, but most importantly, their origin. 1. Sedimentary Rocks Most form under water. Layering (“stratification”) will indicate this. Sedimentary rocks are classified according to the way they were formed and what was deposited: A. Clastics – weathered particles from pre-existing rocks

Classification of Rock Most rocks have a number of minerals in common. Rocks are grouped on the basis of their physical and chemical properties, but most importantly, their origin. 1. Sedimentary Rocks Most form under water. Layering (“stratification”) will indicate this. Sedimentary rocks are classified according to the way they were formed and what was deposited: A. Clastics – weathered particles from pre-existing rocks The particles were lithified

Classification of Rock Most rocks have a number of minerals in common. Rocks are grouped on the basis of their physical and chemical properties, but most importantly, their origin. 1. Sedimentary Rocks Most form under water. Layering (“stratification”) will indicate this. Sedimentary rocks are classified according to the way they were formed and what was deposited: A. Clastics – weathered particles from pre-existing rocks The particles were lithified (turned into rock) by:

Classification of Rock Most rocks have a number of minerals in common. Rocks are grouped on the basis of their physical and chemical properties, but most importantly, their origin. 1. Sedimentary Rocks Most form under water. Layering (“stratification”) will indicate this. Sedimentary rocks are classified according to the way they were formed and what was deposited: A. Clastics – weathered particles from pre-existing rocks The particles were lithified (turned into rock) by: compaction – great pressure from

Classification of Rock Most rocks have a number of minerals in common. Rocks are grouped on the basis of their physical and chemical properties, but most importantly, their origin. 1. Sedimentary Rocks Most form under water. Layering (“stratification”) will indicate this. Sedimentary rocks are classified according to the way they were formed and what was deposited: A. Clastics – weathered particles from pre-existing rocks The particles were lithified (turned into rock) by: compaction – great pressure from the layers of sediment above. It can only work if the sediments are

Classification of Rock Most rocks have a number of minerals in common. Rocks are grouped on the basis of their physical and chemical properties, but most importantly, their origin. 1. Sedimentary Rocks Most form under water. Layering (“stratification”) will indicate this. Sedimentary rocks are classified according to the way they were formed and what was deposited: A. Clastics – weathered particles from pre-existing rocks The particles were lithified (turned into rock) by: compaction – great pressure from the layers of sediment above. It can only work if the sediments are small (e.g. shale & siltstone from clay and silt)

Cementation – is needed for larger particles.

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles).

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified,

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils.

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils. These help indicate what conditions existed at the time of sedimentation.

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils. These help indicate what conditions existed at the time of sedimentation. • Chemical Sedimentary rocks formed from material that was

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils. These help indicate what conditions existed at the time of sedimentation. • Chemical Sedimentary rocks formed from material that was dissolved in the water.

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils. These help indicate what conditions existed at the time of sedimentation. • Chemical Sedimentary rocks formed from material that was dissolved in the water. When the water gets saturated, the minerals precipitate out and form solid rock layers.

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils. These help indicate what conditions existed at the time of sedimentation. • Chemical Sedimentary rocks formed from material that was dissolved in the water. When the water gets saturated, the minerals precipitate out and form solid rock layers. alabaster

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils. These help indicate what conditions existed at the time of sedimentation. • Chemical Sedimentary rocks formed from material that was dissolved in the water. When the water gets saturated, the minerals precipitate out and form solid rock layers. alabaster limestone

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils. These help indicate what conditions existed at the time of sedimentation. • Chemical Sedimentary rocks formed from material that was dissolved in the water. When the water gets saturated, the minerals precipitate out and form solid rock layers. Evaporites will form if the rate of evaporation is great.

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils. These help indicate what conditions existed at the time of sedimentation. • Chemical Sedimentary rocks formed from material that was dissolved in the water. When the water gets saturated, the minerals precipitate out and form solid rock layers. Evaporites will form if the rate of evaporation is great. halite

Cementation – is needed for larger particles. A cement (a mineral that dissolves in water - - CaCO3) holds the sediments together (e.g. sandstone & conglomerate from sand & pebbles). Clastics are usually stratified, and often contain fossils. These help indicate what conditions existed at the time of sedimentation. • Chemical Sedimentary rocks formed from material that was dissolved in the water. When the water gets saturated, the minerals precipitate out and form solid rock layers. Evaporites will form if the rate of evaporation is great. • All chemical sedimentary rocks are monomineralic.

Organic sedimentary rocks form as a result of biologic processes

Organic sedimentary rocks form as a result of biologic processes (decay of plant material [e.g. coal]

Organic sedimentary rocks form as a result of biologic processes (decay of plant material [e.g. coal] or cementing of shell material [e.g. fossil limestone]).

Organic sedimentary rocks form as a result of biologic processes (decay of plant material [e.g. coal] or cementing of shell material [e.g. fossil limestone]). Oolitic limestone

Organic sedimentary rocks form as a result of biologic processes (decay of plant material [e.g. coal] or cementing of shell material [e.g. fossil limestone]). The shell material, however, is not organic.

2. Nonsedimentary Rocks

2. Nonsedimentary Rocks A. Igneous -

2. Nonsedimentary Rocks • Igneous - form as lava or magma cools & solidifies.

2. Nonsedimentary Rocks • Igneous - form as lava or magma cools & solidifies. 1. Intrusive (plutonic) rocks formed

2. Nonsedimentary Rocks • Igneous - form as lava or magma cools & solidifies. • Intrusive (plutonic) rocks formed under the earth’s surface.

2. Nonsedimentary Rocks • Igneous - form as lava or magma cools & solidifies. • Intrusive (plutonic) rocks formed under the earth’s surface. It usually takes a long time to cool, so the minerals crystallize at different temperatures and separate.

2. Nonsedimentary Rocks • Igneous - form as lava or magma cools & solidifies. • Intrusive (plutonic) rocks formed under the earth’s surface. It usually takes a long time to cool, so the minerals crystallize at different temperatures and separate. Dark colors (mafic) harden first (higher temp); while light colors (felsic) harden last.

2. Nonsedimentary Rocks • Igneous - form as lava or magma cools & solidifies. • Intrusive (plutonic) rocks formed under the earth’s surface. It usually takes a long time to cool, so the minerals crystallize at different temperatures and separate. Dark colors (mafic) harden first (higher temp); while light colors (felsic) harden last. • The longer it takes for magma to cool, the _____ the crystals will be

2. Nonsedimentary Rocks • Igneous - form as lava or magma cools & solidifies. • Intrusive (plutonic) rocks formed under the earth’s surface. It usually takes a long time to cool, so the minerals crystallize at different temperatures and separate. Dark colors (mafic) harden first (higher temp); while light colors (felsic) harden last. • The longer it takes for magma to cool, the larger the crystals will be (coarse grained).

Intrusive Igneous Rocks granite

Intrusive Igneous Rocks diorite

Intrusive Igneous Rocks gabbro

Intrusive Igneous Rocks Pegmatite

All molten rock originates in the upper mantle and lower crust.

All molten rock originates in the upper mantle and lower crust. Heat comes from pressure and radioactive decay of the materials deep within the earth.

All molten rock originates in the upper mantle and lower crust. Heat comes from pressure and radioactive decay of the materials deep within the earth. When magma is forced through cracks in the bedrock, intrusions are formed.

Unit 3 Rocks, Soil, Erosion and Mass Movements