 THE
BIOGENIC THEORY
Most scientists believe that natural gas and oil originated millions of years ago, with the first stirrings
of life in ancient seas. A multitude of creatures evolved, feeding upon plants and each other. As these tiny plants
and animals died, they drifted downward in an almost ceaseless shower with other sediments, accumulating layer
after layer upon the ocean floor.
Over time, as the Earth's surface shifted and folded, the sediments were buried by layers of rock, entombing
countless remains of plant and animal life. Heat and pressure transformed the sediments into sedimentary rock --
shale and limestone. The overlying tons of rock eventually transformed the organic remains in the sediments into
a tar-like substance called kerogen.
Continued high pressures and temperatures changed the kerogen into different forms of petroleum:
- the lower temperatures and pressure formed an asphalt-like material
- those in the medium range formed "crude oil"
- the higher temperatures and pressures caused methane, the main component of natural gas, to form
Natural gas can also be created by bacteria which give off methane when they break down organic material. These
bacteria are present in large quantities in garbage dumps, where they feed on banana peels, coffee grounds, paper,
and other organic wastes. At some landfills the methane being produced in collected and sold to natural gas companies.
According to the biological or biogenic theory, all natural gas comes from living things: either the burial
of those that lived long ago, or the breakdown by bacteria of dead plants and animals today.
(from Theories and Conflict: The Origins of Natural Gas by the American Gas Association)
What is a Myth?
The word "myth" comes from an ancient Greek word, "mythos", meaning "a
spoken or written story". A myth is not simply a story, but a story with a purpose. Myths were developed so
people could make sense of the different things that happen to them. This is why every society has had its own
collection of myths.
Using your knowledge about the formation of natural gas, write an ending for Biogenia's story.
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