Transcript C24_Resourcesx

Every year > 25,000 pounds (11.3 metric tons) of new
non-fuel minerals must be provided for you, and each
person in the US, to make the items that we use.
Human History: Stone age, Copper Age, Bronze Age, Iron Age.
7 metals of antiquity: Gold (8000 yra); copper (6200 yra); silver
(6000 yra); lead (5500 yra); tin (3750 yra); iron (3500 yra);
mercury (2750 yra)
Annual Global Consumption of Resources (Stuff!)
• In 2011, the number of cars on roads, globally,
exceeded one billion! (Projection: 1.7 billion by
2035)
• How many and what different materials were
needed to make the early cars at the start of the
20th century?
• Answer: 5 (wood, rubber, glass, steel, brass)
How many different materials are now needed to make cars?
How many different materials are now needed to make cars?
Answer: More than 40 different minerals and metals (plus
multiple plastics, organic materials, glasses, etc.)
1. Crystallization from magma
Ex/ Many minerals and rocks (granite, pumice)
2. Precipitation out of water
Ex/ Salts, gypsum, amethyst, opal, turquoise,
limestone
3. Sedimentation processes
Ex/ Sandstone, shale, limestone
4. Precipitation out of hot fluids near magma, often
associated with precipitation of quartz veins (pegmatites)
Ex/ Metal ores (gold, silver, copper, etc.), sapphire,
emerald, tourmaline
5. Crystallize within preexisting gas bubbles of volcanic
rocks
Ex/ Zircon, topaz, ruby
5. Formation at high pressures
Ex/ Marble, slate, diamond, garnet
6. Alteration of other minerals by weathering
Ex/ clay, iron and aluminum oxides
Copper – humans use 15.7 million metric tons each year!!
3 billion tons geologically available
< 200 years left ??
Ex/ Bingham copper mine in Utah
The first cell phone, 1973, weighed 2.5 pounds, could run
for 30 minutes, and took 2.5 hours to recharge.
What are some of the materials needed to make a modern
cell phone?
Cell phone electronics require many elements such as
copper, gold, palladium, platinum, silver, tungsten….
(these are expensive!)
The electronics use Rare Earth elements like neodymium,
samarium, gadolinium, dysprosium, and praseodymium
* Used for high-performance permanent magnets in
electronics, video games, military devices, disk drives, DVDs.
No good substitutes.
We import ~100% of these! (75% from China)
The receiver and amplifier use arsenic and gallium. We
import 100% of arsenic (Morocco, China, Belgium…) and
99% of gallium (Germany, Canada, UK, China…)
The casing contains magnesium compounds. We import
most of these (China, Canada, Brazil, Austria…)
The battery is made of Lithium. The largest exporter of
lithium is one big salt flat in the Atacama desert at the top
of the Andes Mountains.
Lithium plant at Salar de Uyuni
U. S. Consumption of Minerals, as a % of world use.
U.S. Imports of Minerals
Map of global net metal imports
Map of global mineral depletion
Minerals need to be
naturally concentrated
by geologic processes
to be economically
mined. (Of course, this
depends on the $$)
Ex/ gold = 3 parts per
billion (0.0000003%) of
Earth’s crust
1 wedding band = 3000
TONS of crust!
How do rocks and
minerals form?
Why is there all this copper along the western coast of the
Americas?
Why is there gold in California and Alaska, but not in Florida?
Global Map of Copper Deposits
Mid-Ocean Ridge Thermal Vents
Hydrothermal circulation concentrates certain
minerals and ores.
Erosion can also
help concentrate
minerals to
economic levels…
US Water Usage
The US use of water has leveled off, even though
populations have continued to increase
U.S. Geological Survey Circular 1268, "Estimated Use of Water in the United States in 2000."
…this is due to improvements in water use efficiency for
agriculture, power plants, and awareness of water
conservation
U.S. Geological Survey Circular 1268, "Estimated Use of Water in the United States in 2000."
• Per capita per day water use, USA
– 100 gallons
• Food production
– Pound of rice
• 250-600 gallons
– ¼ pound hamburger meat
• 3000 gallons (800)
– 1 pound cheese
• 650 gallons
• Textiles
– 9 oz cotton t-shirt
• “25 bathtubs”
When the rivers run dry, Pearce,
2006
www.globalchange.gov
Change in US precip, 1958-2008
Predicted
change by
end of
century
(high
emissions
scenario)
www.globalchange.gov
IPCC 4th Assessment Report
• Per capita per day water use, USA
– 100 gallons personal (2 bathtubs)
– (1000 gallons total)
• Rank, in order, the personal water uses in the US:
–
–
–
–
–
–
Drinking water
Taking baths
Taking showers
Washing clothes
Washing up (dishes, etc.)
Flushing toilets
Personal Water Use
– 1 liter of “Fiji” water
• 27 liters (1 + 26 for
production of bottle!)
• And 1 liter of
gasoline
• And 0.5 kg CO2
• 1/6 – 1/3 world’s population:
– No clean drinking water
– 3.3 million deaths/yr
• Major rivers don’t make it to ocean
– Colorado, Rio Grande
• UN: In 2050, 2 - 7 billion
human beings may
experience chronic water
shortages
• “If the wars of this (20th)
century were fought over oil,
the wars of the next century
will be fought over water”
(Ismail Seregeddin, vice
president, World Bank; 1995)
Rate of Groundwater depletion (black = 1 m/yr)
Consequences of overdraft
Very positive future solution: Desalination
(map of current global use)
Desalination
• ~13,000 plants worldwide
– Middle East
• US, Western Europe, Japan
• Projected to double, 2008-2016
• $1->2 to produce daily supply for two
people (US)
– (Avg. municipal water cost for that much:
$.60)
– $ Coming down…
Desalination: Distillation
Desalination: Reverse Osmosis (Barcelona, Spain)
Desalination: Reverse Osmosis
Reverse osmosis
Issues
• $$
• Energy/carbon footprint
– Energy consumption: 3kWh/thousand liters
(incl. filtering, transport)
• Vs 0.2 for surface water
• Dropped by 90% in last 40 yrs, still ~3X minimum
thermodynamic requirement
• Ecological impacts
• Groundwater contamination
• Noise