The original question was:
If you claim oil wasn’t formed until Noah’s Flood, then why are there bacteria that can break it down? How did they evolve?
Answer by Diane Eager and John Mackay
Firstly, what is in oil? Prior to the 1800’s, the oil used was extracted from animals or plants e.g. whale oil, cow fat, seal blubber, olive oil etc. These days the oil used to fuel machinery is called “mineral oil” simply because it is extracted from rocks, rather than from plants or animals. The term “petroleum” literally means “rock oil”.
Mineral oil is a mixture of hydrocarbons – carbon molecules of various lengths with their carbon atoms combined with hydrogen and other atoms such as oxygen, sulphur and nitrogen. But despite the claims that gas and oil have been ‘chemically’ generated deep inside the earth without animal or plant origin, oil and petroleum products show distinctive chemical fingerprints that can only be derived from living things. Provably, they are the breakdown products of life-generated hydrocarbons originally made in living plants and animals. But would such a breakdown have occurred before Noahs Flood?
In living animals hydrocarbons are found in lipids, more commonly known as fats and oils. All living cells contain membranes made of lipids. These form the outer layer of the cell and the internal structure. Living cells also make lipids as a way of storing energy from food. We know this as fat tissue. Plants also make oils and store them, e.g. olive oil, sunflower oil, etc. Other substances in living things, such as proteins and carbohydrates also consist of long chains of carbon atom with other molecules attached to them.
When a living thing dies the lipids from it cells and any stored fats and oils, along with the proteins and carbohydrates are broken down by bacteria into smaller molecules, such as carbon dioxide, so that the carbon and other atoms can be recycled and used again by living things. This is a multistep process, where very long chains of carbon atoms are broken into smaller and smaller chains, until only small carbon-based molecules are left.

You can see this happening today when algae in beach ponds die, and the result is an oily scum that forms petroleum rainbows and Newtonian coloured rings on the pond surface, as seen here. This has fooled many people (John Mackay included) into thinking they’ve struck an oil seep -riche$ are coming! But it happens actually as bacteria decompose the algal matter, and oil is one result. And such processes have necessarily been going on right from the beginning.
Even in a world without animal death, organic matter such as leaves, flowers, fruit, bark, etc. would have been shed from plants, and animal-derived matter was shed from the skin, hair and in the excreta. God’s good, fully recyclable world could not have functioned without the bacteria needed to break down such materials. Even after death came into the world following Adam’s sin, these bacteria would still have been able to keep up with the rate at which organic matter was shed, and break it down. In that pre-flood world, the rate of cell loss into the environment would have been slow, and bacteria would have been able to break down organic materials completely without any partially broken-down hydrocarbons accumulating anywhere as an Oil Deposit.
But at the time of Noah’s Flood there was death on a monumental scale, with billions of tons of dead animals and plants buried under mega-masses of sediment that had been ripped up by the force of the flood water and from volcanic eruptions. This resulted in vast masses of organic matter being buried rapidly and deeply, without enough oxygen for the original surface-dwelling bacteria to use in the breakdown process. Therefore, the buried organic matter could not be fully broken down and remained in the ground as mixtures of short and long chain hydrocarbons and hydrocarbon rings that formed the basis of pitch, tar and oil in petroleum deposits today. When these petroleum reservoirs are released back to the surface, (as we discovered when we started to drill for oil), there already exist bacteria that can break it down even further.
So, in summary: The vast deposits of oil found trapped in rock layers may not have formed until Noah’s Flood, but the substances that make up oil would have been formed in much smaller amounts from the first appearance of created plants and animals on earth. The bacteria needed to recycle these materials had to be part of God’s original good creation, even though they can become a real headache in your petroleum storage tanks in today’s world.
Related Question:
COAL: If earth’s many coal seams formed slowly in swamps, isn’t the world is too old for the Biblical record to be literal? Answer by Bob Powell here.
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