Definition - What does Foraminifera mean?
Foraminifera, also known as protists, are single celled marine organisms with a shell covering on them. They are considered to be one of the richest sources of fossil fuels during decomposition and are present in freshwater and saline water from the last 540 million years. These organisms range in the size of 100 micrometers to 20 cm long. They are informally known as forams.
Petropedia explains Foraminifera
Foraminifera are used for hydrocarbon exploration by many E&P organizations that specialize in offshore oil and gas findings. They are considered to be in the category of amoeboid protists such as green algae or red algae, diatoms, kleptoplastics, etc. Some species are geologically short-lived and some forms are only found in specific environments. Therefore, an E&P organization hires a “paleontologist” who can examine these foraminifera specimens in a small rock sample like those recovered during the drilling of oil wells and determine the geologic age and environment when the rock formed after decomposition of foraminifera organisms. Stratigraphic control using foraminifera is so precise that these fossils are even used to direct sideways drilling within an oil-bearing horizon to increase well productivity.