Fossil Fuels

Fossil Fuels — page 7
FOSSIL FUELS There are about 2,500 coal mines in the United States The productivity of these mines measured in tons per miner per hour has nearly tripled over the past 30 years because of increased use of modern mining machinery The total value of the more than 900 million metric tons of coal produced annually in the United States averages over 20 billion The chief coal-producing states are Wyoming Kentucky West Virginia Pennsylvania Illinois and Texas Anthracite is mined only in Pennsylvania but other states have small deposits Electric utilities are the major consumers of coal in the United States The second largest US market is industrial and retail coal use followed by steel production US coal exports exceed 100 million tons annually with a value of about 4 billion HOW COAL FORMED The world’s coal beds have resulted mainly from the abundance of trees ferns and other plants that existed in the tropiclike forests of the Mississippian and Pennsylvanian Pennsylvanian geological periods These periods called Lower and Upper Carboniferous in Europe and commonly commonly known as the Coal Age lasted for approximately approximately 60 million years from about 358 million to 298 10