how are solid non-fuel mineral resources formed and...

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Part II: Solid Nonfuel Mineral Resources

AuCu SnO2

Marble

Gabbro

Slate Fig. 1.11, p. 11

Resources

Renewable Nonrenewable

PotentiallyRenewable

Freshair

Freshwater

Fertile

soil

Plants andanimals(biodiversity)

Directsolarenergy

Winds,tides,flowingwater

Fossilfuels

Metallicminerals

Non-Metallic

minerals & rocks(iron, gold,

copper,aluminum)

(clay, sand,marble, slate)

or “Nonrenewable

Mineral Resources”

These two are

sometimes

Called: “Solid

Nonfuel

Mineral

Resources”

What’s Environmental

Degradation?

How are solid non-fuel mineral resources

formed and concentrated?

• Rock CycleWeb Links: please read about this:

http://imnh.isu.edu/digitalatlas/geo/basics/diagrams.htm

http://www.usgs.gov/science/instance.php?term=8

A series of events / processes, both internal and external,

through which a rock changes between igneous, sedimentary

and metamorphic forms. Cycle takes millions of years and is

responsible for concentrating Earth’s Nonrenewable

Mineral Resources.

• + Plate Tectonics / Hydrologic Cycle……

How are solid non-fuel mineral resources formed and concentrated?

• Internal Processes (magma generation, hot water circulation, pressure & heat)

– Magmatic deposits

– Hydrothermal deposits

– Metamorphism

• External Processes (weathering, erosion, transport and deposition by wind and water; evaporation)

– Sedimentary deposits: wind, water, placers

– Evaporites

– Secondary Enrichment

Fig. 12-19a, p.351

Magmatic Rocks & Minerals

granite, diorite, quartz, feldspar, chromite,

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Common Magmatic Rock / Mineral Resources

& Their Use (Read later)

• Granite / Diorite / Gabbro: building materials, dimension stone,

roads, shoulders, furniture, counter tops, interior/exterior surfaces

• (FeMg)Cr2O4 Chromite: important ore of chromium, used to

harden and manufacture steel, coloring agent, making bricks,

tanning leather, dyes, also used in common materials such as cars,

planes, engines, satellites, weapons, home appliances (form from

basaltic magmas)

• Opal (Quartz): gems, abrasives, mortar, glass, silica brick,

porcelain, paints, sandpaper, scouring soaps, wood filler, radios,

watchesl

• Platinum, Magnetite, Cobalt and Manganese: also used in

manufacturing cars, planes, engines, satellites, weapons, home

appliances (form from basaltic magmas)

Hydrothermal Deposits

Metallic chemical elements, Sulfides and Oxides form

in association with magma and water.

Hydrothermal deposits often occur in “veins”

Disseminated deposits / gangue

e.g. Au rich deposits of CA Sierra Nevada.

Black Smokers (undersea hot springs) form at Oceanic

Ridges (divergent plate boundaries) and at undersea hot

spots.

Fe

Au, Cu

Pb, Zn, Ag, CuSn, Mo

FeAu,

Cu

Pb, Zn,

Ag, Cu

SnIron

Chromium

Nickel

Formation of Metals: Hydrothermal and MagmaticRead this Figure over very carefully

Know these symbols / names:

Fe = Iron

Au = Gold

Ni = Nickel

Cu = Copper

Pb = Lead

Zn = Zinc

Ag = Silver

Sn = Tin

Cr = Chromium

Iron

Copper

Zinc

Lead

Divergent

Plate BoundaryConvergent

Plate Boundary

Hydrothermal Activity

Black smokers (undersea hot

springs) form at mid-ocean

ridge/divergent boundaries.

Hydrothermal vein deposits. e.g.

rich Au deposits of CA Sierra

Nevada.

Picture taken from

Submersible Alvin,

1/7/09

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Common Hydrothermal Mineral Resources & Their UseRead later

• Fe / Iron: bikes, cars, bridges, magnets, machines, nails, tools, food

supplements

• Fe / Hematite (Fe2O3 ): ore of iron, pigments, polishing powder, jewelry

• Au / Gold: circuit boards, electronics, jewelry, planes, space shuttles, compact

discs, cameras, telephones

• Cu / Copper: electrical purposes, circuit boards, wire, sculpture,

brass = Cu and Zn, bronze = Cu + Sn and some Zn, German silver

• Pb / Galena (PbS): lead sulfide, major source of lead, used in making metals, pipe, sheets, solder, glass

• Zn / Sphalerite (ZnS): ore of zinc, important metal alloy used in making

brass, paint, zinc oxide, batteries

• Ag / Silver: photographic film and paper, photosensitive glass, mirrors,

batteries, silverware

• Sn / Tin: metals, coins, cups, plates, cans, solder, opalescent glass, enamel,

weather resistant vinyl siding



– Magmatic deposits Rare Earth Elements– Hydrothermal deposits

– Metamorphism



– Evaporites


The Rare Earth Elements

“REE”Web Link

The 17 Rare Earth Elementshttp://en.wikipedia.org/wiki/Rare_earth

_element

Ru Ruthenuim Os Osmium

Rh Rodium Ir Iridium

Pd Palladium Pt Platinum

Se Selinium

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Wide Variety of uses: medical (MRI), military, missiles, clean

energy technology, catalytic converters, magnets, hybrid car

batteries.

Consumer Products: cell phones, computer hard drives, monitors,

power tools, sun glasses, wine bottles, fluorescent light bulbs, TVs,

automobiles, SUV’s

MRI’s

missiles, drones

night vision goggles

• Also used in Cell Phones

Until the mid 1980’s, US led the world in REE production; has

~13% of world reserves.

China has ~48% of world reserves, but supplies >97% of the

world’s needs. Russia, Canada and Australia also have large

deposits.

Over 3 Square miles

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Mountain Pass Rare Earth Mine in Mountain Pass California,

Mojave Desert. Closed in 2002, re-opened in August 2012

Web Link: The Only American Mine for Rare Earth Metals

http://www.theatlantic.com/technology/archive/2012/02/a-visit-to-the-only-

american-mine-for-rare-earth-metals/253372/

Environmental Concerns• Need to excavate a lot of earth / dig huge holes / takes a lot of

energy + a lots of solid waste rock.

• Some elements associated with the REE are radioactive such as

Uranium and Thorium. They end up in slurry pools and can enter

groundwater.

• Toxic acids and chemicals are required during the refining process,

often end up in slurry pools and can enter groundwater.

• Baotou, a city in China where ~80% of REE are mined produces

~10 million tons of wastewater/year.

• Birth defects and Leukemia have been linked to rare earth refinery

in Malaysia and China

• In 2008, ~1/3 of REE in China were mined illegally by heavy

polluting, violent criminal gangs.

The Lynas Plant in Malaysia is

the world's largest processing

facility of rare earths.


Most of the world’s major metal deposits occur at past or present plate

boundaries. Surface processes also play an important role in

concentrating nonmetallic minerals and rocks.




– Metamorphism


– Sedimentary deposits

– Evaporites

– Water / Placer deposits


Metamorphism How are solid non-fuel mineral resources formed and concentrated?







– Metamorphism



– Evaporites


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Sand Mining in Monterey Bay has been occurring

since 1906, ~150,000 – 250,000 cubic yards/yr,

with no regulation until 1960s.

3 companies for ~80 years, only one is left.

A connection between mining and shoreline erosion

was determined in the mid

1980s, but still 1 company

mines ~200,000 cubic yards

each year.

Sand Mining in Monterey Bay http://coastalcare.org/2014/09/monterey-bay-california-beach-sand-mining-from-a-national-

marine-sanctuary-by-gary-griggs/

(web link)

Sedimentary Deposits: Sand and gravel accumulate in river

channels and bars, coastal offshore bars, sand dunes, beaches and

glacial outwash plains.

After deposition sediments lithify by compaction and cementation.

Materials used for: road beds, cement production, bricks, tiles, abrasives,

water filtration, glass production…..

Placer DepositsRead this slide over very carefully.

“Point Bars”

Evaporites: (Salts: halite, gypsum, borates) water evaporates

from shallow inland seas or lakes in warm arid climates.

Materials used in: making glass, ceramics, metals, preservatives,

cleaning agents, water softeners……..








– Metamorphism



– Evaporites


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Secondary Enrichment

How are mineral resources found?Understand the geologic/plate tectonic history of an area

Make Maps: rock formations, faults, structure

Drill, extract and analyze rock/sediment samples

Aerial photos and satellite images,

reveals outcrops and types of rock types

Seismic & gravitational surveys give

info about buried rock layers

Chemical analysis of water and plants

to detect minerals leached into water and

absorbed by plants

Remote sensing: (detect /analyze wave

transmitted energy) reveals outcrops and

types of rock

Measure radiation, magnetism to detect

radioactive metals, iron and other

How are Mineral Resources Extracted?

Surface Mining

machines strip away millions

of tons of “Overburden”

(rock/earth covering ore) and pile

it up as waste material

sometimes called “Spoil”

1) Open-pit mining:

commonly used surface

mining technique; used for

mining most major metal

deposits, also sand, gravel and

stone. The Palabora open pit in NE South Africa. The hard rock

allows the pit walls to be cut much steeper than is

normal in open-pit Copper mining.

Bingham Copper Mine, Utah>4km wide, 1.2 km deep, >6 billion tons of rock mined since 1906

More Surface Mining2) Hydraulic Mining: wash away overburden on hillsides;

mine uplifted placer deposits. In CA huge volumes of sediment

washed into SF-San Joaquin delta harming navigation and

agriculture, ~ 1850’s – 1890’s.

~13 billion cubic

yards of sediment

have been washed

away from the

Sierra Nevada

3) Dredging: used on underwater mineral deposits;

gold mining of CA riverbed sediments until 1960s;

leaves great piles of spoil alongside channels called

spoil banks/dredge fields.

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How are ores processed?

• Remove undesired parts of ore (gangue)

• Smelting extracts metals from other elements

• Pure metal is then converted to desired product by manufacturing

companies

Drawbacks? Results in air, water, soil pollution; solid and liquid

hazardous wastes; safety and health hazards Start Here:Surface Mining

Metal ore

Separation

of ore fromgangue

Scattered in environment

Recycling

Discarding of product

Conversion

to product

Melting metal

Smelting or “Extractive Metallurgy” is the practice of extracting metal from ore, purifying it, and recycling it

Why do we mine?Concerns? Environmental degradation from mining and processing, depletion

time, economic depletion, exhaustion, import dependence, high cost

Supply and Consumption of Mineral Resources

• Economic Depletion

– Costs more to find, extract, transport and process mineral than

deposit is worth.

– Options: 1) recycle or reuse existing supplies, 2)waste less, 3) use

less, 4) find substitute, 5) do without.

• Depletion Time:

– time it takes to use up 80% of reserves of a mineral at a given rate

of use.

• US currently imports ~50% of its most important non-fuel minerals.

– Used faster than they can be produced here

– Foreign ores are higher grade and can be extracted cheaper than

US reserves

Present

Depletiontime A

Depletiontime B

Depletiontime C

Time

Pro

du

cti

on

C

B

A

Recycle, reuse, reduceconsumption; increase

reserves by improvedmining technology,higher prices, and

new discoveries

Recycle; increase reservesby improved mining

technology, higher prices,and new discoveries

Mine, use, throw away;no new discoveries;

rising prices

how are solid non-fuel mineral resources formed and...

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