Minerals are the raw materials that support much of modern life - everything from transportation to the growing of food. Chemists, all sorts of manufacturers, farmers, and a variety of artisans depend upon minerals to conduct business. Virginia's mineral deposits are vast and varied, but coal remains most important to the Commonwealth.
In Virginia the dollar value of mineral resources produced has risen almost threefold in the past 25 years, from $540,595,000 in 1973 to $1,702,576,00 in 1997. Yet this figure tells only a small part of the story of the importance of the state's geologic resources. Soil and water, two of the most valuable resources, and without which there would be no life, are not included. Nor are parks and other scenic and recreational areas, most of which owe their natural beauty to the geology of their location. The Blue Ridge mountains, the caverns and caves, and the Shenandoah Valley are only a few examples.
The science of geology is the study of the earth and its history, and the processes and forces which are constantly at work changing the face of the earth. It is such a broad subject that it has been divided into a number of individual sciences: geophysics and oceanography for example. Geologists try to explain how the earth was formed and has changed through time.
Many industries rely upon a geologist to locate new sources of raw materials. Through the use of field mapping and specialized investigative techniques, geologists discover and develop such resources as petroleum, iron ore, copper, limestone, and sulfur.
Virginia can be divided into five physiographic provinces, based on the general configuration of the land surface. From east to west, they are the Coastal Plain, Piedmont, Blue Ridge, Valley and Ridge, and Appalachian Plateau. Each of these physiographic provinces is underlain by distinct combinations of rock types, and each had a somewhat different geologic history (which classifies them uniquely from Virginia's growing regions, or geographic provinces, discussed in the agriculture chapter).
The Coastal Plain Province, extending inland for more than 100 miles, is predictably flat. The surface slopes gently eastward from elevations of less than 200 feet along its western margin to the Atlantic Ocean and Chesapeake Bay; then to Virginia's Eastern Shore-the southern portion of the Delmarva Peninsula. The Chesapeake Bay is the dominant topographic feature of the province. Throughout the region, younger sediments from the Cretaceous, Tertiary, and Quaternary ages (dating from 1 to 80 million years ago) lie atop older crystalline and metamorphic rocks of the Piedmont.
Economic materials mined in the Coastal Plain Province are sand, gravel, and clay. More recently, mining has begun for heavy mineral sands (ilmenite, leucoxene, and zircon) in deposits discovered in Dinwiddie, Sussex, and Greenville counties.
Largest of Virginia's physiographic provinces, the Piedmont extends from Virginia's "fall line" west to the Blue Ridge Mountains. Structurally, it contains a complex of metamorphic and plutonic rocks, overlain in a number of places by Triassic-age sedimentary beds (that are 200-230 million years old). Elevations range from around 100 feet in the east to more than 1,000 feet in the foothills of the Blue Ridge. Local relief generally is low but becomes less gentle to the west.
Metamorphosed rocks characterize this region: schists, gneisses, slates, phyllites, marble, and quartzites. In many areas, they have been altered by intruding granite and other igneous rocks. Mined in the Piedmont are kyanite, slate, vermiculite, granite, gabbro, diabase, and feldspar.
The rocks that form the Blue Ridge Province or mountains include a basement complex of Precambrian (800-1,200 million years old) granite and granulites along with late Precambrian metamorphosed sedimentary rocks. This old terrain of Precambrian-age metamorphosed sedimentary and volcanic rocks contains the "oldest" rocks in Virginia-including Old Rag Granite, dating back approximately 1.2 billion years.
The Blue Ridge follows a northeast-southwest alignment of the Appalachians in the west-central portion of the state. The two highest mountains in the state, Mt. Rogers (elevation 5,720 ft.) and White Top (elevation 5, 520 ft.) are located in the southern reaches. Blue Ridge rocks are quarried for quartzite as crushed stone and, in the past, mining occurred for copper, iron, manganese, and a limited amount of tin.
The Valley and Ridge Province exhibits great variation, both topographically and geologically. Thick sedimentary layers accumulated during the Paleozoic Era (and date back 570 to 320 million years). Strata consisting of shale, dolostone, and limestone dominate on the east and grade westward into strata comprised generally of sandstone, siltstone, and shale. Diabase and other dikes are present.
With the exception of the lower valley of the Shenandoah River, the Great Valley gives way westward to a complex of northeast-trending ridges and narrow valleys, with the ridges rather than the valleys dominating the landscape. Sandstones are the primary ridge formers, and the valleys are cut into less resistant limestone and shale formations. Several summits of more than 4,000 feet are found in this area. Resources currently extracted from this province are limestone, dolostone, sandstone, gypsum, iron oxides, clay, oil, natural gas, and shale.
The Appalachian and Cumberland Plateaus fringe the Valley and Ridge along much of the western margin of the state. Toward the end of the Paleozoic, sedimentation increased and brackish to non-marine deposits spread westward across the older marine formations, similar to the present Coastal Plain. Large swampy areas provided the material for the coal strata in southwestern Virginia. In fact, the southwest Virginia coalfield is totally contained within this province. In addition to coal, this province contains valuable resources of methane, natural gas, and some oil, along with some crushed stone.
The most important mineral resources of Virginia are coal, crushed stone, sand and gravel, lime (from limestone and dolostone), and natural gas. Kyanite, which is mined in Buckingham County, is the only deposit currently being mined in the United States. Virginia is also the only producer of "Virginia Aplite" (used to make glass) and the second leading producer of vermiculite, used in insulation, packing, and potting soil.
The non-fuel minerals industry is an important aspect of Virginia's economy. In 1997, Virginia ranked 22nd nationally in non-fuel mineral production. That year, there were 359 industrial mineral mining operations throughout the Commonwealth. At least 87million tons of non-fuel minerals with a value of 600 million dollars were produced. Most of this production is from crushed stone quarries, and sand and gravel mining operations.
The importance of the fuel minerals industry to Virginia's economy is best exemplified by the coal industry. In 1997, there were 92 surface coal mines and 264 underground coal mines in operation. Approximately 36.8 million tons of coal were mined in 1997 with a value of 959 million dollars. The coal was mined from 40 coal beds in Lee, Wise, Dickenson, Buchanan, Scott, Russell, and Tazewell counties. Virginia ranked 8th in national coal production that year.
Also in 1997, 18.1 billion cubic feet of conventional natural gas and 39.7 billion cubic feet of coal bed methane gas were produced from the southwest fields with a value of 143.5 million dollars. There were 62 producing oil wells in Lee and Wise counties in 1997, producing 10,337 barrels of oil. There were 1,017 conventional gas wells and 995 coal bed methane wells in production in 1997.
From the coal used to provide energy, to the aggregates used for our infrastructures, it is obvious that the state's mineral industry is extremely important to Virginia's economy and well-being. A grand total of 1.07 billion dollars of mineral commodities can be attributed to the Commonwealth in 1997.
Conservation of our mineral resources means efficient use of materials. Every year, mining companies improve methods of recovery to obtain as much as possible of the usable mineral from the ore that is mined. Likewise, petroleum and natural gas producing companies institute practices that lead to greater overall production. Another example of efficient use of mineral resources is the recovery of fly ash produced by the burning of coal from power generating plants. Fly ash (amounting to 2 million tons produced in Virginia in 1996) is used in structural fills, as a flowable fill in place of concrete, and also in lightweight concrete cinder block.
Mining And Mineral Facts - Historic Highlights
Source: VA Dept. of Mines, Minerals and Energy, 1998
Energy does things for us. It moves cars along the road and boats along the water. It bakes a cake in the oven and keeps ice frozen in the freezer. It plays our favorite songs on the radio and lights our homes. Energy makes our bodies grow and allows our minds to think. Energy is a doing and moving thing. In essence, energy is the ability to do work.
Sources Of Electricity In Virginia, 1997
Coal - 50.3%
Nuclear - 45.9%
Natural Gas - 2.2%
Petroleum - 1/5%
Hydro & Other - .1%
There are ten sources of energy commonly used to provide electricity, to move our vehicles from place to place, and to grow the food we need to survive. These energy sources are vital to Virginia's future. For many years, Virginians have released the energy from coal and natural gas reserves; used gasoline refined from petroleum to move cars, trucks, boats, and planes; and harnessed the energy in water. Virginia is also a leader in unleashing the power of nuclear energy - or energy that is locked in the nucleus of an atom.
Energy sources are classified as renewable or nonrenewable. Renewable resources can be re-used or replenished in a short amount of time. Nonrenewable resources such as fossil fuels, by contrast, can be used up and it will take millions of years and very special conditions to create them again. Fortunately for Virginians, the Commonwealth has a variety of both forms of energy resources.
Renewable energy sources are in use everywhere.
A unique property of energy is its ability to change forms. For example, the energy in water at the Bath County pumped storage hydropower facility changes from potential to kinetic energy as it is released during peak demand periods. Its potential energy is recharged as it is pumped back into the higher reservoir duirng low demand periods.
Today, hydropower is Virginia's leading renewable source of energy because of its value in generating electricity. Smith Mountain Lake in southwest Virginia is a vast hydroelectric reservoir generating electricity for customers in Virginia and surrounding states. Hydropower is supplemented by the use of other power: geothermal, biomass, solar, and wind. Together, these sources make up a very small portion of the energy used in Virginia each year - less than one percent.
Virginia continues to get most of its energy from non-renewable energy sources because the state has very large coal and natural gas deposits. Coal is the most valuable of Virginia's mineral resources and is used primarily to generate electricity. Virginia coal was first commercially produced near Richmond in 1738. Local industries at the time used it in iron foundries and blacksmithing. Later, when railroads linked southwest Virginia with other states and the port of Norfolk, the vast coalfields of southwest Virginia became major suppliers, producing coal not only for Virginia but for other states and countries.
Virginia continues to export large amounts of coal. In 1998, close to 11 million tons were loaded into rail cars for export by just one of Virginia's principal carriers-Norfolk Southern. Our coal is bituminous, meaning that it has a resinous nature and is quite easy to burn. Over 80 percent is extracted from underground mines. Virginia coal is sought by many states because of its clean attributes. It has a low sulfur content and, therefore, produces very little sulfur dioxide when burned.
Virginia mimics the rest of the nation in its use of other nonrenewable energy sources. For example, we use petroleum to move ourselves and the goods we use from place to place. We use natural gas to generate electricity and to heat our homes and cook our food. Many a backyard barbecue depends upon the use of propane gas, which is produced from natural gas and petroleum. Much of this natural gas comes from the southwest corner of the state, the same region in which we find coal. In fact, with advancing technologies, Virginians are able to harvest natural (methane) gas in a process that takes it out of the coalbeds.
Another nonrenewable energy source harnessed by Virginians is nuclear power. Uranium atoms are used to generate electricity when a process called nuclear fission is used at Virginia's two nuclear power plants: North Anna Nuclear Power Station on Lake Anna, and Surry Nuclear Power Station in Surry. These power plants split atoms of uranium to create large amounts of electricity, used by residential and commercial customers throughout the state.
The Commonwealth is home to tremendous natural energy resources, making our energy inexpensive and fairly easy to use. And because Virginia has an extensive distribution network-railroads, pipelines, and rivers-criss-crossing the state, we'll continue to have energy within our borders for many years to come. But all of us can take steps to conserve energy and ensure its availability to future Virginians.
Although coal production in Virginia remains strong, between 1984 and 1997 trends reveal that:
Virginia's 5 Largest Power Plants by Capacity*
NOTE: one megawatt = 1,000 kilowatts, or 1 million watts
*All are owned by Virginia Power and, together, account for over 65 percent of generating capacity in the state. Net summer capability shown.
Here are some ways to become a wise energy-miser:
Teaching about energy is not easy. There are many advantages as well as disadvantages to using the resources we count upon each day. Educating people about the trade-offs of energy decisions, specifically their impacts upon the environment and the local economy, will help all of us become better consumers while extending the lifespan of Virginia's energy resources.
Geology & Minerals