Embed Size (px)
Citation preview
ROCKS AND MINERAL
RESOURCESGeology
The Walker School
Essential Questions
What elements are important for our society?
What is the average crustal content of common
minerals?
To what extent must a metal be concentrated above
its average crustal content to make mining it
economically viable?
Rocks
A rock is an
aggregate of one or
more minerals.
There are over a
1,000 different types
of rocks on Earth.
Rock Classifications
Physical Properties
Chemical Composition
Specimen of Tourmaline and Quartz
Rock Formation Cycle
WHAT MINERALS ARE
IMPORTANT TO OUR
SOCIETY?
Minerals
A mineral is a naturally
occurring, inorganic
solid with an orderly
crystalline structure and
a definite,
homogeneous chemical
composition.
Medieval Manuscripts
Much of the ink used in
these brilliantly colored
manuscripts came from
various minerals.
Economically Important Minerals
Aluminum
Coal
Copper
Iron
Lead
Salt
Tin
MATTER, ELEMENTS, AND
BODING
Periodic Table of Elements
Fig. 3-4, p. 74
Types of Bonds
Ionic Bonds
Covalent Bonds
Metallic Bonds
Van Der Waals BondsIncrease
In
Bond
Strength
Ionic Bonds in Minerals
Fig. 3-6a, p. 76
Covalent Bonds
Fig. 3-7, p. 76
Covalent Bonds in
Graphite
Covalent Bonds in
Diamonds
Sheering
TO WHAT EXTENTS MUST A
MINERAL BE CONCENTRATED
TO BE ECONOMICALLY
VIABLE?
Common Elements in Earth’s Crust
Fig. 3-11, p. 80
Mineral Contents of Common Rocks
About 0.0001 to 0.008 weight percent of copper,
lead, zinc and tin
About 0.00001 to 0.000002 weight percent of
platinum, silver, and gold
About 6.0 weight percent of iron
Economic Determinants of Viable Mineral Deposits
Mining Technologies
Market Value
Economically Viable Deposits
25 x crustal content for iron
60 x crustal content for copper, lead, zinc, and tin
Only several parts per million for gold and
platinum
HOW ARE MINERALS
FORMED?
Mineral Formation Processes
Sedimentation (coal)
Precipitation (salts, metals)
Crystallization from Magma Plutons (ores)
Changes in Temperature and Pressure (ores)
Fluid Inclusions (ores)
Sedimentation of Coal
Crystallization from Magma Plumbs
Fluid Inclusions
Mineral Groups
Silicates Contain
Silicon
Oxygen
Quartz (SiO2)
Carbonates Contain
Carbon
Oxygen
One or More Metallic
Elements
Dolomite
Oxides Contain
Oxygen
One or More Other
Elements (Usually
Metals)
Iron Oxide
Sulfates and Sulfides Contain
Sulfur
One or More Other
Elements
Iron Sulfide - Pyrite
Halides Contain
Halogen Ion
chlorine, fluorine,
bromide and iodine
One or More Other
Elements
Fluorite
WHAT ARE THE PROPERTIES
OF MINERALS AND HOW ARE
THEY IDENTIFIED?
Mineral Identification
Crystalline Structure
Hardness
Luster
Color
Streak
Cleavage
Fracture
Specific Gravity
Fluorescence
Magnetism
Tenacity
Radioactivity
Piezoelectricity
Reactivity to Dilute
Acids
Color
Imperial Topaz - Al2F2SiO4
Streak
Hematite is Fe3O4
Luster
Minerals are Crystalline
Fig. 3-8, p. 78
Most minerals atoms are arranged in regular,
3D frameworks
Typical of Halite Typical of Pyrite Typical of
Diamonds
Typical of
Quartz
Cleavage Patterns
Fig. 3-17, p. 88
WHAT ARE NONRENEWABLE
MINERAL RESOURCES?
Metallic Mineral Resources
Iron
Tin
Copper
Aluminum
Gold
Platinum (PGE’s)
Tin Mine, Bolivia
Non-Metallic Mineral Resources
Salt
Clay
Sand
Phosphates
Soil
Phosphate Mine,
Florida
Energy Resources
Coal
Oil
Natural Gas
Uranium
The Rössing Uranium Mine; located in the Namib
Desert, Erongo Region, Namibia.
HOW ARE BURIED MINERAL
DEPOSITS FOUND?
Underground Detective Work
Aerial Photos
Satellite Image
Radiation-Measuring Equipment
Magnetometer
Gravimeter
InfoTerra - Satelliteshttp://www.infoterra.co.uk/applications_ogm_mineral.php
Example Mineral Analysis
Mineral Resource GIS Databasehttp://gdr.nrcan.gc.ca/minres/data_e.php
Magnetometer Survey
Measures changes in the
Earth’s magnetic field
caused by magnetic
minerals, such as iron ore.
Deep-Ocean Gravimeter
Measures differences in
gravity caused by
differences in density
between an ore deposit
and the surrounding rock.
HOW ARE BURIED MINERAL
DEPOSITS REMOVED?
Mining Strategies
Surface Mining
Sub-Surface Mining
Surface Mining Methods
Open-Pit Mining
Glory-Hole Mining
Dredging
Area Strip Mining
Contour Strip Mining
Mountaintop Removal
Appalachian Mountain Top Removal of Coalhttp://www.appvoices.org/index.php?/site/mtr_overview/
Mineral Deposits Associated with
Magma Intrusions
Located in Siberia,
the mine in the
picture is apparently
the world's largest
diamond mine.
Kimberlites
Mineral Deposits Associated with Plate
Boundaries
Fig. 2-26, p. 62
Escondida Copper Mine, Chili
is today the world's largest producing mine with 750,000 metric tons of production which was 5.6% of the world's production in 2000.
Sub-Surface Mining Methods
Digging Deep Vertical Shafts
Blast Subsurface Tunnels
Use Machinery to Remove Ore
WHAT ARE THE ENVIRONMENTAL
IMPACTS OF USING MINERAL
RESOURCES?
Impacts (mining, processing, use)
Scarring and disruption of land surface
Collapse of land above mines
Wind or water erosion of toxic mineral wastes
Thermal water pollution
Acid mine drainage
Emission of toxic chemical into atmosphere
Noise Pollution
Nickel Tailings in a River
