Happy Tuesday Pull out a ½ sheet of paper
1. Physical properties of a mineral are predominantly related to 1. the external conditions of temperature, pressure, and amount of space available for growth. 2. the chemical composition and the internal arrangement of the atoms that make up the mineral. 3. crystal form, hardness, cleavage and fracture, and density. 4. all of the above.
2. The color of a mineral is predominantly related to: A. its chemical composition. B. its internal arrangement of atoms. C. its luster. D. temperature and pressure conditions at the time of crystallization.
3. The silicates are the most common and abundant mineral group, because silicon and oxygen are: A. the hardest elements on Earth s surface. B. the two most abundant elements in Earth s crust. C. found in the mineral quartz. D. formed in a tetrahedral structure.
4. The property of a mineral to break along planes of weakness is referred to as A) cleavage. B) hardness. C) fracture. D) bond strength.
8) Mohs scale is based on minerals that have different A) cleavage directions. B) colors. C) hardnesses. D) shapes.
1. Physical properties of a mineral are predominantly related to 1. the external conditions of temperature, pressure, and amount of space available for growth. 2. the chemical composition and the internal arrangement of the atoms that make up the mineral. 3. crystal form, hardness, cleavage and fracture, and density. 4. all of the above.
2. The color of a mineral is predominantly related to: A. its chemical composition. B. its internal arrangement of atoms. C. its luster. D. temperature and pressure conditions at the time of crystallization.
3. The silicates are the most common and abundant mineral group, because silicon and oxygen are: A. the hardest elements on Earth s surface. B. the two most abundant elements in Earth s crust. C. found in the mineral quartz. D. formed in a tetrahedral structure.
4. The property of a mineral to break along planes of weakness is referred to as A) cleavage. B) hardness. C) fracture. D) bond strength.
8) Mohs scale is based on minerals that have different A) cleavage directions. B) colors. C) hardnesses. D) shapes.
Today Salt crystal ACT The Rock cycle Rock types ACT Thursday Finish Rock cycle PP Lab # 3 Rock types
The Formation of Minerals Minerals crystallize systematically based on their respective melting points. The first minerals to crystallize from a magma are those with the highest melting point and the lowest amount of silica. The last minerals to crystallize from a magma are those with lower melting points and higher amounts of silica. Feldspars and quartz
This is a rock
ROCK: Naturally occurring mixture of minerals
How to Describe Rocks Photo: E. Puris
APPEARANCE OF A ROCK defined by 1) color; 2) mineralogy; 3) size of crystals
Source: Tom Bean
Sediment Rock fragments, shells, etc.
Bedrock Hand Sample Outcrop
Geologic Map of Oregon
Source: USGS
Three Rock Types
Igneous rocks Formed by the solidification of magma Distinguished from each other using: Texture Grain size Composition
Igneous Rock Texture Aphanitic- too small to see (sugar cookies) Porphyriticboth large grains and groundmass (chocolate chip cookie) Phaneritic- Large interlocking grains (rice crispy treat)
IGNEOUS ROCKS GRAIN SIZE: -Extrusive: cool above ground (tiny crystals) -Intrusive: cool below ground (large crystals)
Igneous Rock Composition Name (Color light to dark) Felsic- Light Granite (Explosive, ash, pyroclastic volcanoes) Intermediate- diorite (Subduction zone volcanoes) Mafic-Dark Basalt (Slow flowing lava; Hawaii volcanoes) Ultramafic- Very Dark peridotite (mantle) Silica content (SiO 2 ) High (>65%) Intermediate Low Very low (<40%) Magnesium oxide, Iron oxide content (MgO), (FeO) Low Intermediate High High
Hawaii Felsic or Mafic? Intrusive or extrusive? Texture?
Mt St Helens Felsic or Mafic? Intrusive or extrusive? Texture?
Solidified Lava Flow This is an example of an: 1. Intrusive igneous rock 2. Extrusive igneous rock 3. Sediment
Volcanic Rocks in the PNW
Frozen Magma Chambers in California are: 1. Intrusive igneous rocks 2. Extrusive igneous rocks 3. Sediment
Igneous Rocks Granite Andesite Basalt
Global Distribution of Igneous Rocks
Sedimentary Rock Cemented fragments of sediment (clastic) or Precipitation of a mineral (chemical) Only type of rock to contain fossils
Where do you find sediment?
Modern Mississippi Delta Source: World Perspectives/Gamma
Strata and Bedding
SEDIMENTARY ROCKS: result from surface processes (weathering, erosion, precipitation of dissolved minerals)
Sedimentary Rocks Shale Sandstone Limestone
Distribution of sedimentary rock
Metamorphic Rock Sedimentary or igneous rock changed by pressure, temperature or both Foliated Non foliated
Strata can be tilted.
Strata can be folded
Formation of METAMORPHIC ROCKS
Metamorphic Rocks Slate Marble Gneiss
Mountain Building Creates Metamorphic Rocks
Distribution of Metamorphic Rocks
Igneous Rocks Magma Heat & Pressure Sediments Burial, Compression &Lithification Melting Sedimentary Rocks Melting Metamorphic Rock Heat & Pressure