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How to Locate Coal Deposits

Coal, though it looks like black rock, is not rock at all, but compressed plant matter. When plants die in one area over a long-enough period of time, and are covered over with clay and sediment, they get compressed. Over thousands of years they decay and are compressed further until they become hard and rock-like. Coal is made up of mostly carbon, and it is full of the solar energy stored by the plants that went into forming it, according to Steve Kluge, author of "Earth Science Regents."

Though coal was popular in the 19th and early 20th centuries, its usage declined in the later 20th century as other energy sources, such as oil, natural gas and nuclear, grew in popularity. Rises in oil prices often cause people to turn to coal if it is available.

Things You'll Need

Geological survey maps of your search area
History references for your search area
Picture of shale
Picture of clinker

Instructions

- 1
  Check the history of mining in the area you intend to search. If history shows that coal has often been discovered in the area, it is a good place to start looking. In the United States, most coal comes from Wyoming, West Virginia, Kentucky, Pennsylvania and Texas, according to Kennesaw State University.
- 2
  Look at geological survey maps of the area you intend to search. Look for the presence of clay and shale, both of which are often found with coal. Concentrate your search for coal near where clay and shale are found.
- 3
  Look at the history of the land you will be searching, back millions of years. If the land once was swamp, conditions will have been ideal for forming coal. Swamps often form peat, which in time becomes lignite, which is the simplest form of coal and can later become other forms of coal. Look for coal in formerly swampy areas.
- 4
  Go to the area you will be searching and look for coal on the surface of the land, which often indicates the presence of a seam below the surface. Learn to identify clinker, and search for it as well. Clinker is what is left after coal burns. Old lightning strikes or prairie fires may have ignited coal near the surface, leaving clinker behind. This could indicate a seam of coal still existing below ground. Also look for shale and clay, which are often found near coal.

Rocks & Minerals