Mineral & Fossil Fuel Formation and Extraction

Mineral & Fossil Fuel Formation and Extraction APES 2012

Warmup… • How does the uneven distribution of minerals and resources impact social and political relationships between different countries?

Uneven distribution of Minerals • Oxygen, silicon, aluminum, and iron are unevenly distributed over 88 percent of the crust • Ores consist of concentrated accumulation of economically valuable minerals and metals

Global mineral distribution

Types of mining • Two kinds of mining take place on land: • SURFACE MINING • Strip Mining • Open-pit Mining • Mountaintop Removal • Placer mining • SUBSURFACE MINING

Surface mining • STRIP MINING • Removes strips of soil and rock to expose ore. • Used when ore is relatively close to the Earth’s surface • (ex. Sedimentary materials such as coal and sand)

Surface mining • OPEN-PIT MINING • Creates a large pit or hole in the ground. • Used when resource is close to the surface but extends beneath the surface horizontally and vertically (ex. Copper mines) Kennecott Bingham Canyon Mine near Salt Lake City, UT one of the largest open-pit mines in the world

Surface mining • MOUNTAINTOP REMOVAL • Miners remove the entire top of a mountain with explosives. • Large earth-moving equipment removes the resource and deposits the tailings in lower-elevation regions nearby, often in or near rivers and streams • (ex. Coal) The Last Mountain

Surface mining • PLACER MINING • The process of looking for metals and precious stones in river sediments. • River water is used to separate heavier items like diamonds, tantalum, and gold, from lighter items like sand and mud. (ex. California gold rush)

SUBsurface mining • Used when resources are more than 100 meters (328 feet) below Earth’s surface. • (ex. Coal, diamonds, and gold)

Turn and talk… • What are some possible environmental impacts of mining? • Which type of mining causes the most harm to the environment? • Which type of mining creates the least amount of damage to the environment?

Mining safety and the environment • The extraction of mineral has various environmental impacts and human health consequences • Deposit of spoils and tailings could cause contamination and the blocking or changing the flow of rivers.

Mining safety and the environment • Subsurface mining can cause acid mine drainage, where lower pH water from the mine is pumped and drained above ground, lowering the pH of nearby soils and streams. Acid Mine drainage

Mining safety and the environment • Subsurface mining accidents are extremely dangerous to miners, while long term exposure to gases and particles can cause respiratory diseases. • Human impact Subsurface mining

Turn and talk… • How will the growth of human populations and industrialization affect the demand for mined resources? • How will this impact the environment? • Are mineral resources considered renewable or non-renewable? Why?

Mining legislation • Governments have sought to regulate the mining process for many years: • The Mining Law of 1872 (General Mining Act) – regulates the mining of silver, copper, and gold ore as well as fuels, including natural gas and oil, on federal lands. Written to encourage development and settlement in the western United States, it contains very few environmental protection provisions. • The Surface Mining Control and Reclamation Act of 1977– regulates surface mining of coal and the surface effects of subsurface coal mining. The act mandates that land be minimally disturbed during the mining process and reclaimed after mining is complete • Mining legislation does not uniformly regulate all of the practices that can have harmful effects on air, water, and land.

Working towards sustainability • In the U.S. the Surface Mining Control and Reclamation Act of 1977 requires coal mining companies to restore the lands they have mined. Regulations also require other types of mining operations to do some level of restoration. • Fill in the hole or depression in the landscape. • Fill material must be relatively free of metals, acids, and other compounds and shaped to follow the preexisting contours. • The land must be replanted to re-create the communities of organisms that inhabited the area before mining. • Properly completed reclamation makes the soil physically stable so that erosion does not occur and water infiltration and retention can proceed.

And then there’s oil • Oil drilling explained –

Fossil fuel formation

Fossil Fuels COAL • between layers of sediment. • As surface coal reserves deplete, subsurface mining techniques are used to mine for coal ores.

Environmental impacts of extraction - coal • Burning fossil fuels… • Removing surfaces from a mountaintop…. • Chemical runoff from strip mining…

Coal mining legislation • Mountain top extraction is the “worst” for the environment • In the US, mining companies must “restore” strip mined land (is that even possible?) • In 2002, the US loosened regulations on mountaintop removal, allowing companies to dump removed and slide material into river valleys • The rest of the world has even looser regulations

Fossil Fuels PETROLEUM • A fluid mixture of hydrocarbons, water, and sulfur that occurs in underground deposits. Petroleum removed from the ground is known as crude oil and contains natural gas. • Formed as the remains of ocean-dwelling phytoplankton (microscopic algae) that died 50 million to 150 million years ago get trapped between porous sedimentary rock and nonporous rocks. • Petroleum fills the pore spaces in the rock over millions of years and migrates up to the highest point of the porous rock, where it is trapped by nonporous rock. • Petroleum is generally extracted through the use of pumps through drilled wells. • Once extracted petroleum is transferred through pipelines and tankers to various refineries where it is refined into tar, asphalt, gasoline, diesel, and kerosene.

Primary and secondary extraction • Primary extraction: Easiest and cheapest. Whatever oil can be pumped without extra effort • Secondary extraction: Input more energy/matter to force the oil out. Much more expensive and energetically demanding. • Secondary extraction methods are only economically feasible if primary extraction is not possible

Petroleum environmental impacts • Burning fossil fuels adds CO2 to the atmosphere (usage) • Pollution of water through oil spills and leakage (extraction)….sludge • Drilling can alter local ecosystem health: (vegetation, wildlife, etc). For example, drilling in Alaska has been shown to adversely affect bird populations and reproductive success and affect caribou and polar bear populations

Fossil fuels NATURAL GAS • Exists as a gaseous deposit on its own as well as a component of petroleum. • 80 to 95 percent methane (CH4) and 5 to 20 percent ethane, propane, and butane. • Mostly extracted in association with petroleum but direct drilling for natural gas has recently been explored. • One way of extracting natural gas is through fracking Fracking CNN

Natural gas environmental impacts Extraction can: • Contaminate groundwater (for drinking!) • Alter air quality (for breathing!) • Bring harmful chemicals to the surface

Fossil Fuels OTHER FOSSIL FUELS • Oil Sands and Liquefied Coal are two types of fossil fuel deposits that contain a great deal of energy but are not readily available. • Oil sands are slow-flowing, viscous deposits of bitumen mixed with sand, water, and clay • Oil sands can be extracted by surface mining, which have serious negative environmental impacts. • Requires large amounts of water to extract, can be inefficient, and releases more CO2 than conventional oil production • Liquefied Coal is created from converting solid coal into a liquid fuel through a process known as CTL (coal-to-liquid) • With more goal reserves than petroleum reserves, liquefied coal can help alleviate the world’s dependence on petroleum • However, emissions from liquefied coal are more than twice of those from conventionally produced oil.

In your notebooks… • What are some environmental impacts of extracting these fossil fuels? • Do you think the extraction methods for one are worst than the others? Why or why not? • Can you think of any major controversies in recent years over extraction of certain fossil fuels? • Are these fuels considered renewable resources? Why or why not?

Mineral & Fossil Fuel Formation and Extraction