2012 lecture 1 slides - university of washingtoncourses.washington.edu/ess212/lecture_files...why is...

Earth Materials!

ESS 212!5 CREDITS!

ESS 212: EARTH MATERIALS (5 credits) Instructor: Olivier Bachmann (bachmano@uw.edu) TA: Frances Rivera-Hernandez (riveraf@uw.edu),

Nicholas Castle (ncastle@uw.edu) TA2: Pamela Wichgers Lectures (SIG 225): M W F 10:30 - 11:20 Laboratory (JHN 127): T Th 3 sessions starting 8:30 am Office hours: tbd Textbook: Nesse, William D. (2000 or 2012) Introduction to Mineralogy. Oxford Univ. Press Other book for mineralogy: Wenk and Bulakh (2004), Minerals: Their Constitution and Origin. Cambridge Univ Press Source book for petrology: Blatt, H., Tracy, R.J. & Owens, B.E. (2006) Petrology: Igneous, sedimentary, and metamorphic, 3rd edition. Freeman Course website: http://courses.washington.edu/ess212 MSA website: http://www.minsocam.org/

Organization and Grading!

ü 1/2 mineralogy, 1/2 petrology!ü Lectures (3 hours a week)!

ü  I do most of the work!!ü Mid-term and final exam!

ü Lab (4 hours a week)!ü  You do most of the work!!ü Mid-term and final exam!ü  Lab reports to turn in!

Grading!

ü Mid-term exam => 30% of your grade ü Final examination => 35% of your grade ü Labs (Assignment, mid-term, final) =>

35% of your grade

Mineralogy!

A 5-week intro!

Introduction!

ü Chapter 1 of Nesseʼs book!

Why is a knowledge of mineralogy important?

• Physical and chemical properties of minerals determine the way the earth behaves e.g., elastic properties determine seismic velocities

thermal properties control melting/crystallization processes magnetic properties determine the earth’s magnetic field, etc. etc.

• Minerals are the source of noble metals (Au, Pt, Ag…), base metals (Cu, Ni, Pb, Zn, Hg, Ti, Al, Cr, Si…), industrial minerals, (gypsum, asbestos, diamond, graphite…), gems (diamond, emerald, ruby,…), fertilizer (phosphate minerals), etc. etc.

• Minerals play a key role in climate control, e.g., via the weathering process involving the production of clay minerals, sequestration of CO2 in carbonate minerals. Minerals are increasingly important as nuclear waste repositories.

• The entire solid earth and much of all the planets are made up of minerals

• Minerals we eat. http://www.mtnhigh.com/minrals.html

How many minerals?!

ü ~4300 (Hazen and al., Am Min 2008)!ü Only ~ 100 that are common !ü Only ~ 15 that can be called rock-forming minerals (see hand-out for lab)!

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Definition of a mineral!

ü  Naturally occurring ü  Homogeneous (single phase) ü  Crystalline solid = Ordered, repeated arrangement of

atoms/ions making up the mineral ü  Definite (but generally not fixed) chemical

composition, i.e., fixed stochiometry ü  *[inorganic] This property is often included in the

definition but many organisms secrete minerals such as calcite and aragonite into their tests and shells, forming minerals no different from their inorganic equivalents.!

History of mineralogy!

When did humans start to get interested in minerals?!

ü >40,000 years ago!ü For art and trading!

Paleolithic wall paintings in the Lascaux Cave, France ~ 17000 years ago!

Oldest Mine in the world?!

Lion’s Cave (Swaziland) > 43,000 years ago

From Greeks to Renaissance!

ü Earliest-preserved books!ü Theophrastus (~300 BC)!ü Pliny the Elder (~70 AD)!ü Georgius Agricola (1522-1555)!

ü De Re Metallica (1556) - Hand sample identification (see pdf on website)!

De Re Metallica!

17th century onwards!

ü Crystallography (Steno, Werner, Hauy)!ü Optical mineralogy!ü X-rays!

Early methods!

New methods!

Chuquicamata!

Selling!

ü Old!

ü New!

Mineral evolution!ü  The mineralogy of terrestrial planets evolved as a consequence of varied

physical, chemical and biological processes (Hazen et al. 2008). ü  ~12 nano-scale mineral phases in pre-stellar dense molecular clouds ü  ~60 primary chondrite minerals ü  ~250 different minerals in altered chondrites, achondrites and differentiated asteroids. ü  Earthʼs subsequent prebiotic mineral evolution involved a sequence of geochemical and

petrologic processes, which resulted in ~ 1500 different mineral species.

ü  Biological processes, starting in the Archean, changed atmospheric and ocean chemistry (e.g., Paleoproterozoic “Great Oxidation Event” and Neoproterozoic increases in atmospheric O2) and are responsible for most of Earthʼs 4300 known mineral species.

ü  Mineral evolution arises from three primary mechanisms: (1) progressive separation and concentration of elements from their original relatively uniform distribution; (2) an increase in range of intensive variables such as pressure, temperature, and the activities of H2O, CO2 and O2; and (3) generation of far-from-equilibrium conditions by living systems.

Minerals in Washington!

ü Many localities!ü Visit http://www.washingtonminerals.com/!