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Rock Review

Other minerals are important for the full description of igneous rocks:

Olivine, Pyroxene, Hornblende, Biotite and Muscovite

Bowen’s Reaction Series

and Classification Common Igneous Rocks

Fine

Grained

(Extrusive)

Coarse

Grained

(Intrusive)

Felsic Intermediate Mafic

Rhyolite Andesite Basalt

Granite Diorite Gabbro

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Sediment

Classification

by Grain Size

Conglomerate

Siltstone

Sandstone

Shale

Bowen’s Reaction Series and Sedimentary Rocks

Least Common Minerals in Sandstones

Most Common Minerals in Sandstones

Metamorphic Texture Changes

Granite Gneiss

Formation of

Foliated Metamorphic Rocks

Shale Gneiss

Mic

roscope

Hand S

am

ple

Schist

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Metamorphic Texture Changes

Quartz Arenite

Quartzite

Limestone Marble

Bowen’s Reaction Series and Metamorphic Rocks

Highest Temperature Metamorphic Minerals

Lowest Temperature Metamorphic Minerals

Identifying Rocks

Foliated/Layered Non-Foliated/Non-Layered

Sedimentary Metamorphic Igneous

Identifying Rocks

Grains Crystals

Sedimentary Metamorphic Igneous

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Plate Tectonics

Pangea

Distribution of Late Paleozoic

Fossils Bathymetry of the Ocean Floor

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Volcanoes of the World

Volcanoes Correlate Globally with

Deep Earthquakes Benioff Zone of Seismicity

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Composition of the Crust

Granite Basalt,

Gabbro

Si, Al,

Na, K Si, Al,

Ca, Fe, Mg

Composition of the Earth

Plate Tectonic Model Mantle Convection

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Tectonic Plates

Plate Tectonics,

Rocks, and Metals

Average Abundance of Ore Metals

in Earth’s Crust

Metal Average Abundance in

the Crust

Silver (Ag) .050 ppm

Gold (Au) .002 ppm

Copper (Cu) 25 ppm

Iron (Fe) 350000 ppm

Nickel (Ni) 20 ppm

Lead (Pb) 20 ppm

Tin (Sn) 5.5 ppm

Zinc (Zn) 71 ppm

ppm = parts per

million

= grams per

tonne

Requirements for Ore Deposit Formation

All ore deposits require the following:

A source of metals

A means to transport the metals

A fluid

An energy source (heat or gravity)

A means to concentrate the metals at one location in

an extractable form

Change in chemical conditions

Physical sorting

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Examples of Ore Deposit Models

Magma-Related Ore Deposits

Magma as a Source of Metals (Epithermal)

Magma as a Heat Engine (VMS)

Erosion/Deposition-Related Ore Deposits

Physical Sorting of Ore Minerals (Placer)

Chemical Weathering and Concentration of

Ore Minerals (Supergene)

Epithermal Deposits

Volcanogenic Massive Sulfide

Deposits (VMS) Placer Deposits

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Plate Tectonic and Metals