Crude oil is a fossil fuel and, as the name implies, it is derived from fossils. Over time the remains of vegetation and various organisms, such as bacteria and algae, are covered by an increasing amount of soil before they are converted through heat and pressure into matter composed largely of hydrocarbons. This material, known as crude oil or petroleum, is the product of eons of this process.Know More
Scientists believe most of the crude oil extracted today is generated from marine organisms, such as zooplankton and algae. They suspect larger animals may also be part of the mix.
Once these remains begin to change as a result of heat and pressure, they become what geologists refer to as kerogen, a waxy substance. With more heat, kerogen becomes liquid and gas hydrocarbons.
Crude oil hydrocarbons largely consist of cycloalkanes and alkanes, as well as oxygen, nitrogen, sulfur and copper, iron and nickel.
Geologists know where to locate oil reservoirs based on rock formation types. Such formations are characterized by deeply buried source rock containing hydrocarbon material, a permeable reservoir rock for it to gather in and a rock seal to keep the material from reaching the surface before it is extracted with drills and pumps.Learn more about Earth Science
Crude oil mainly consists of hydrocarbon molecules, but impurities, such as sulfur, nitrogen, oxygen, iron, arsenic, vanadium, copper, nickel, sodium chloride, calcium chloride and magnesium chloride, are also present. The hydrocarbon molecules include straight chains, branched chains and rings.Full Answer >
Fossils form when a dead animal or plant is covered by sediment. Eventually, the organic matter in the bone or plant, such as the blood vessels and tissue, slowly turns into rock, which becomes known as a fossil.Full Answer >
There are four types of fossils: mold fossils, cast fossils, trace fossils and true form fossils. Fossils are divided into two distinct categories: fossilized body parts, such as teeth, claws, bones and embryos, and fossilized traces, including nests, tooth marks, droppings and footprints.Full Answer >
Fossils are primarily found in sedimentary rocks because these rocks form at low temperatures and pressures. Igneous rocks form at temperatures and pressures that are high enough to destroy any organic remains. On rare occasions, fossils are found in metamorphic rocks, but they are deformed by the heat and pressure.Full Answer >