Minerals vs Rocks • Minerals: • Inorganic • Solid • Crystalline structure • Each classification has a specific chemical composition • Rocks: • Solid • Cluster/consolidation of minerals • Classified by formation
Types of Minerals I. Silicates • Most common mineral group…75% of the Earth’s crust • Contains Silicon and Oxygen tetrahedron
Some Types of Silicate Minerals Mica Olivine Orthoclase (feldspar)
Types of Minerals II. Non-silicates Do not consist of Si and O2 together Oxides: 02 + metal Sulfides: S + 1 or more metals Sulfates: S+O2 Halides: Cl or F + K or Na or Ca Carbonates: C + O2 Native elements: single element (Au, Ag)
Examples of Non-Silicates Magnetite (oxide) Gypsum (sulfate) Sphalerite (sulfide) Halite (halide) Gold (native element) Calcite (carbonate)
Rocks are Classified by how they were formed • Rock Types: • I. Igneous”Formed by Fire”forms from magma or lava that cools and solidifies (crystallization). • a)Intrusive: formed below the Earth’s surface • examples: • Granite • Diorite
b.) extrusive: formed at or above the Earth’s surface examples: Obsidian Pumice Rhyolite
STUFF TO KNOW ABOUT IGNEOUS ROCKS The rate of cooling of magma influences the size of the mineral crystals The faster the cooling, the smaller the crystals. The slower the cooling, the larger the crystals.
Igneous Rocks are classified by: -Chemical composition of the crystallized magma -Texture and mineral content The Bowen’s Reaction Series shows: as magma cools, minerals organize in an orderly fashion(see page 127 in textbook)
There are Five Types of Textures of Igneous Rocks • Fine grained: very small crystals • Coarse grained: majority of mineral crystals are uniform in size and large enough to see w/out a microscope • Porphyritic: has two very contrasting sizes of crystals • Glassy: no mineral crystals are developed • Fragmental: contain broken, angular fragments of rocky material produced during an explosive volcanic eruption.
II. Sedimentary Rocks:Formed from the lithification of sediment.(lithification:process of converting sediments to rocks through cementation and compaction)Examples:Conglomerate, Sandstone, Shale, Limestone conglomerate Limestone
Stuff To Know About Sedimentary Rocks The process of weathering produces sediment Q. Huh? What is sediment? A. Unconsolidated particles that are created by………..
Weathering and erosion of rockChemical precipitation from solution in water Has been transported by water, wind and/or glaciers
More about Sedimentary Rocks!!!(OH BOY!) Classifications of Sedimentary rocks: 1. Chemical (aka non-clastic) precipitated from water . Ex Limestone, Coquina 2. Detrital: (aka clastic)formed from the accumulation of material that originated and was transported in the form of solid particles derived from weathering (mechanical/chemical) Ex:Conglomerate, Breccia Sedimentary rocks make up about 75% of the ROCKS at the Earth’s surface
III.METAMORPHIC:forms from rock that has been subjected to great heat and pressure. (It has undergone a metamorphasis….get it?) Marble Slate Gneiss
2 Major Classifications of Metamorphic Rock 1.Foliated:a texture that gives the rock a layered appearance gneiss slate 2.Non-foliated: rocks that do not exhibit a layered appearance Marble quartzite
Regional Metamorphism: Large areas of rock undergo change due to great amounts of pressure (raise the pressure, the temp. raises also) Contact Metamorphism: Metamorphic rocks are created when they come into contact with magma. More On Metamorphic!!!(things just don’t get any better)