The Mineral and Fuel Industry of Indiana
Mineral and fuel commodities mined in Indiana include common clay
and shale, limestone and dolomite, construction sand and gravel,
industrial sand, sandstone, gypsum, peat, and coal. Depending on the
quality and type of limestone, it may be sold as dimension stone for
construction of buildings, crushed for use as aggregate, or used in
the production of concrete or cement. Crushed stone is also processed
into agricultural lime or used for sulfur dioxide removal in
coal-fired electric power plants with limestone scrubbing systems or
may be finely ground for use as fillers in various products.
In addition to agricultural lime, some stone is imported from
Michigan and processed by two northern Indiana companies into lime
used mostly by the steel industry on Lake Michigan. Dolomite is sold
as crushed stone. Some has been sold as decorative dimensional stone.
A small quantity of sandstone is produced on demand for small
landscaping or construction projects.
The clay and shale produced in Indiana is primarily used for cement,
concrete blocks, tiles, animal feed, absorbents, plastics, adhesives,
or paint. Gypsum is primarily used in production of wallboard and
cement. Peat is used for soil improvement, on golf courses, for
earthworm culture and by nurseries. Construction sand and gravel is
used mostly for concrete aggregate, roadbase and road stabilization,
fill, for asphaltic concrete and for snow and ice control. Industrial
sand is used for refractory purposes and by foundries for molding,
for blasting, and in glass manufacture. A small quantity of
freshwater pearls are also harvested in Indiana. Approximately 89
percent of all coal produced in Indiana is burned in coal-fired
electric power plants, 10 percent powers industrial plants, and 1
percent goes for residential use. Oil and natural gas are also
extracted from many wells in Indiana.
Underground Coal Mining in Indiana
Underground coal mining began in Indiana in the early 1830's. With
the coming of the railroads, the number of underground mines grew
rapidly in the late 1800's and early 1900's. Peak coal production of
29 million tons came in 1918 because of the demand created for coal
by World War I. With improved surface mining since the 1920's,
underground mining declined, so that today about 2 percent of
Indiana's coal comes from underground mines.
About 900 million tons of coal has been produced in Indiana by
underground mining. The total area undermined is more than 100,000
acres, or about 150 square miles, mostly in Vermillion, Vigo,
Sullivan and Knox Counties. Mines have ranged from one-person
operations to mines employing hundreds of workers. The state's
largest mine - more than 9 square miles - was King's Station Mine
in Gibson County south of Princeton. It closed in 1972.
Surface-Mined Land in Indiana
More than 160,500 acres have been disturbed by surface mining for
coal in Indiana. This mining has been limited to 21 counties in
southwestern Indiana, mostly in Clay, Greene, Pike, Sullivan, Vigo
and Warrick Counties.
Before the 1920's, nearly all coal produced in Indiana was mined
underground. Since then the amount of coal produced by surface
mining has gradually increased, so that now nearly all coal is mined
in Indiana by stripping overburden from above the coal.
Early attempts to reclaim mined land were concurrent with large-scale
mining, but these voluntary attempts were limited to reforestation.
Indiana's first compulsory-reclamation law was passed in 1949.
Reclamation has improved, so that in many places it is difficult
to determine whether an area has been mined. Some land is
considerably improved after surface mining.
By the 1950's many markets for Indiana coal had disappeared, but
these losses were compensated by the increased use of coal by
electric utilities. In 1980 about 80 percent of Indiana coal
production was used to generate electricity
Distribution of Coal in Indiana
Our Indiana coalfields lie on the east edge of a broad, gently
downwarped bedrock structure called the Illinois Basin (stippled area
on map). Coal-bearing rocks are restricted to an area of about
6,500 square miles in southwestern Indiana because those that have
existed elsewhere in Indiana have been removed by erosion.
Because of downwarping, the rocks dip to the southwest at 30 feet
per mile, and each coalbed is at increasingly greater depth in that
direction. The most active mining in Indiana has been in Vigo,
Sullivan, Greene, Knox, Pike and Warrick Counties where the thicker
and more widespread rocks of Middle Pennsylvanian age are near the
surface. Most Hoosier coal is now strip mined, but vast resources
of coal are available for underground mining.
Indiana limestone or Bedford limestone is a common term for Salem
limestone, a geological formation primarily quarried in south central
Indiana between Bloomington and Bedford. Salem limestone, like all
limestone, is a rock primarily formed of calcium carbonate.
The limestone was deposited over millions of years as marine fossils
decomposed at the bottom of a shallow inland sea which covered most
of the present-day Midwestern United States.
The first Indiana limestone quarry was started in 1827, and by 1929
Hoosier quarries yielded 340,000 m* (12 million cubic feet) of usable
Men working in a quarry of the Indiana Limestone Company, Inc., Bedford.
Buildings such as the Empire State Building, The Pentagon,
and the United States Holocaust Memorial Museum feature Indiana
limestone in their exteriors.
Limey shale overlaid by limestone.
Oil and Gas in Indiana
The history of oil and gas development in the state of Indiana
officially began in the mid-1800s with the early settlers' practice
of drilling for salt water. Salt was a necessity for the preservation
of foodstuffs and critical to the early state's agricultural industry;
shallow wells were sunk in many parts of the state to obtain salt
water that could be evaporated to produce salt. Drilling was
probably accomplished by using a "spring pole" method. Early settlers
also became aware of gas springs and oil seeps along the Ohio River
in Harrison and Crawford Counties.
Following the news of the success of Colonel Edmond Drake's oil well
in Titusville, Pennsylvania in 1859, oil exploration moved westward
into Ohio and Indiana. Between 1862 and 1869, wells were drilled in
Pulaski County and Vigo County and gas and oil were discovered but
not further developed. Gas was discovered in what would become the
Trenton Field near Eaton in Delaware County in 1876. Beginning in
1886 and continuing into the first decade of the 20th century, gas
and then oil were discovered and developed in east central Indiana.
A wild untethered boom ensued that ultimately resulted in thousands
of wells being drilled; this was America's first giant oil field
(greater than 100 million barrels of oil). The gas was used to
attract and then fuel numerous industries in the region. In fact,
the existence of Muncie, Anderson, Marion, and Kokomo as
manufacturing centers can be directly attributed to the development
of the Trenton Field. In addition to these industrial complexes,
the oil boom led to the development of refining and petrochemical
industries in the Calumet region. The boom quickly ended in the
beginning of the 20th century because wasted resources and
unregulated drilling practices caused a precipitous drop in
production. Unfortunately much of the resource was wasted or lost
through the burning of gas at the surface and the contamination of
oil by fresh water within the subsurface reservoir.
As gas and oil production quickly declined in northern Indiana, new
discoveries were being made in the southwestern part of the state
known as the Illinois Basin. Production from fields in Vigo and Pike
Counties was rapidly followed by new discoveries in Sullivan and
Gibson Counties. Unlike the single field of northern Indiana that
produced from a single reservoir, these new discoveries produced from
many smaller fields and a variety of different reservoirs at
different depths. Also, unlike the Trenton Field, the Illinois Basin
fields produced mostly oil, not gas. Soon all the counties located
in the southwestern part of the state were contributing to oil
production. Production peaked in 1956 at over 12 million barrels for
the year. Since that time both the number of holes drilled and the
production for the state have declined. In 1997, Indiana produced
just under 2.5 million barrels of oil and 526 million cubic feet of
Current Activity and Future Prospects
Since the early 1960s, the amount of oil produced in Indiana has
declined. Close examination of this decline reveals that changes in
the price of oil are directly related to the number of wells drilled
and consequently, the volume of oil produced. For instance, the
reversal of the steep decline in the 1960s and 70s can be attributed
to the energy crisis of 1973 and Iranian crisis of 1979. After 1986
a steep declined resumed, resulting from a dramatic lowering in the
price of crude oil. In this same time frame, the number of holes
drilled within the state has declined from over 1,200 in the early
1980s to around 200 in recent years. Most of these holes are drilled
as development wells in existing fields in attempts to extract more
oil. A low level of "wildcat" exploration still takes place within
the state, but at an average price of $12 per barrel, exploration
for new reserves is very limited.
There is a fair potential for the discovery of significant new
reserves in the state. Much of the state has been drilled; however,
this drilling reached only the first few thousand feet of depth.
A considerable portion of the subsurface remains unexplored, and
many thousands of feet of potential reservoir exist, especially in
the southern portion of the state. Although the deep subsurface
geology of this region is thought to be similar to northern areas
of the state, details of thermal maturity, migration pathways, and
trapping mechanisms are unknown. In addition to untested geology,
the application of new technologies to explore for and produce oil
and gas could hold the key to unlocking some of Indiana's resource
potential. These new technologies, some of which are being used in
the development of the New Albany Shale as an unconventional gas
source, include the application of advanced seismic acquisition and
processing techniques, new drilling technologies including horizontal
drilling, and complex completion techniques such as liquid CO2
Gypsum, Clay, Sand and Gravel
Gypsum, one of the most widely used minerals in the world, literally
surrounds us every day. Most gypsum in the United States is used
to make wallboard for homes, offices, and commercial buildings; a
typical new American home contains more than 7 metric tons of
gypsum alone. Moreover, gypsum is used worldwide in concrete for
highways, bridges, buildings, and many other structures that are
part of our everyday life. Gypsum also is used extensively as a
soil conditioner on large tracts of land in suburban areas, as well
as in agricultural regions.
Gypsum deposits are in the NE and SW, and sand and gravel are found
throughout the state.
Indiana is an important producer of masonry cement. Mining of
gravel, gypsum, and stone is also commonplace in the central portion
of southern Indiana.