Lab 5: Exploring for PetroleumKey Q: How is petroleum

found?

Petroleum & Natural Gas

• Petroleum (oil): liquid fossil fuel made of hydrogen & carbon

• Natural gas: Gaseous fossil fuel made mainly of methane

Forms from marine plants & animals that die-sink-begin to decay-become buried. If temperature

conditions are right oil or natural gas will form, and can collect underground in areas called reservoirs.

Formation of petroleum and natural gas

Reservoirs

Geology of Petroleum Deposits• Three conditions must be present for oil &

natural gas reservoirs to form:SRS: Source, Reservoir, Seal

– Source rock: rich in organic matter buried deep enough for it to turn into oil; Source of the oil

– Reservoir: porous sedimentary rock that the oil can flow through & collect in.

– Seal: dense rock that stops the oil from rising up to the surface.

Methods of Exploration

• Geologists map the rocks & project down– Looking for SRS

• Seismic exploration– Create a small explosion and study how

density difference cause waves to refract & reflect

• Drill test wells– Method is very expensive