**1.1 What is meant by an oil spill?**

What exactly is oil? In line with the basic definition, oil is an organic compound that is soluble or readily soluble in water but not readily soluble in other liquids and is found in crude oil. An oil spill occurs when oil floats on the surface of bodies of water and is carried by the wind, currents, and tides [1–5].

The most visible source of oil pollution in the marine environment is operational oil discharges and spills from ships, particularly tankers, offshore platforms, and pipelines. Take the Amoco Cadiz oil tanker as an example (**Figure 1**). In 1978, this tanker ran aground off the French coast, causing 68.7 million gallons of oil to spill.

**Figure 1.** *Sinking oil tanker Amoco Cadiz.*

Large spills like these are unusual occurrences. Additionally, an oil transfer accident caused the oil tanker Mega-Borg (**Figure 2**) to spill 5.1 million gallons of oil [1, 6].

Ixtox 1 exploration well blowout in 1979. In 1980, when workers were able to stop the blowout, 140 million gallons of oil were estimated to have leaked into the ocean (**Figure 3**). Only the intentional oil spills that put an end to the Kuwait-Iraq war in 1991 are smaller than this, making it the second-largest spill in history (**Figure 4**).

**Figure 2.** *Explosion of tanker mega-Borg.*

**Figure 3.** *Exploratory well Ixtox 1 in 1979.*

**Figure 4.** *Exploratory of oil wells during the Kuwait-Iraq war of 1991.* In fact, during times of conflict, one nation may choose to pour tons of oil into the oceans of the opposing nation [1, 4, 6, 7].
