Fossil Fuels Flashcards
What are the different forms of petroleum?
Gas, oil, tar sand and oil shale
What’s the significance of fossil fuels having high energy density?
Transportation cheaper, easier to produce higher temp, small amount of fuel
What are the high temperatures produced from coal commonly used for?
Smelting of ores, generation of electricity
How do fossil fuels impact the level of technological development?
Many applications that use energy have been developed to use fossil fuels such as cars, trucks, ships, aircraft and most power stations
Why are significant amounts of coal and oil unexploitable?
Deposits are too deep, found in small amounts or located in areas which are difficult to reach
Where is natural gas contained?
Trapped in fine grained impermeable shale deposits
What is oil shale?
Fine grained sedimentary rock containing solid hydrocarbons
What does oil shale yield?
Oil and combustible gas upon destructive distillation
Why can availability be limited?
Economic viability, unacceptable pollution, habitat damage and extraction processes can cause local earth tremors
What is the basis of most of the world’s energy?
Crude oil
How is coal formed?
Plant remains accumulate and undergo bacterial decay, this is buried by sediment at high temp and pressure, increasing carbon content and the plant material is metamorphosed into coal
How can coal be mined?
Open-cast mining, adit mining and deep mining
What are the features of open cast mining?
Heavily mechanised, more economically viable and coal must be close to the surface
What is Adit mining and why is it no longer extensively used?
Removing coal horizontally from a valley and creating cooling heaps on the valley, Aberfan 1966 is an example of why it’s unsafe
What are the features of deep mining?
Labour intensive so relatively expensive
How does deep mining work?
A vertical shaft is sunken into the ground, the miners then dig horizontal galleries away from the shaft. The coal is then removed up the shaft and separated from spoil
What are some other environmental damages caused by coal?
Habitat loss, transport and ground subsidence
How does petroleum form?
Phytoplankton die and sink to sea floor, where they are preserved from immediate decomposition by anoxic black muds, most crude oil forms at temps of approx 100C with increased pressure
What forces oil to the surface when pipes are drilled?
Natural pressure of gas above the oil or by water beneath the oil
What conditions need to be met for oil and gas to be trapped underground as reserves?
Trapped by layers of impermeable rock, antiform trap
What are the environmental impacts of oil extraction and transport?
Oil pollution, marine seismic surveys and habitat damage caused by pipeline construction