Which of these is known as "black gold"?
Petroleum, also known as crude oil and oil, is a naturally occurring, yellowish-black liquid found in geological formations beneath the Earth's surface. Petroleum is a fossil fuel derived from ancient fossilized organic materials, such as zooplankton and algae.[
Petroleum has mostly been recovered by oil drilling. Drilling is carried out after studies of structural geology, sedimentary basin analysis, and reservoir characterisation. Once extracted, oil is refined and separated, most easily by distillation, into numerous products for direct use or use in manufacturing, such as gasoline (petrol), diesel and kerosene to asphalt and chemical reagents used to make plastics, pesticides and pharmaceuticals.
The extreme monetary value of oil and its products has led to it being known as "black gold".
More than 4000 years ago, according to Herodotus and Diodorus Siculus, asphalt was used in the construction of the walls and towers of Babylon. The Chinese were the first to record the use of petroleum as fuel as early as the fourth century BCE.
Petroleum exploitation has significant negative environmental and social consequences. Oil has also been a source of conflict leading to both state-led-wars and other kinds of conflicts.
Production of petroleum is expected to reach peak oil before 2040 as global economies reduce dependencies on petroleum as part of climate change mitigation and a transition towards renewable energy and electrification.