1. Virginia

2. Regions of Virginia Virginia has a billion-year-long tectonic and geologic history. Virginia has five physiographic provinces produced by past episodes of tectonic activity and continuous geologic activity. Each province has unique physical characteristics resulting from its geologic past. Geologic processes produce characteristic structures and features.

4. The five physiographic provinces of Virginia are Coastal Plain, Piedmont, Blue Ridge, Valley and Ridge, and Appalachian Plateau.

5. The Coastal Plain is a flat area composed of young, unconsolidated sediments underlain by older crystalline basement rocks. These layers of sediment were produced by erosion of the Appalachian Mountains and Piedmont and then deposited on the Coastal Plain when sea levels were higher in the past. The Coastal Plain (Tidewater) Region is an area of low, flat coastal plain (an area of low, flat land that lies along an ocean) that begins at the Atlantic Coast and stretches inland to the Fall Line. There are four peninsulas in the Coastal Plain (Tidewater) Region. From the James River to the North Carolina border, has two natural features- -the Hampton Roads harbor, which is the one of the world's largest natural harbors, and the Dismal Swamp

6. The Piedmont is an area of rolling hills underlain by mostly ancient igneous and metamorphic rocks. The igneous rocks are the roots of volcanoes formed during an ancient episode of subduction that occurred before the formation of the Appalachian Mountains. The western edge of the Tidewater Region is formed by the Fall Line. The Fall Line is a line of small waterfalls and rapids. The land of the Piedmont Region is higher than the land of the Tidewater Region. The Piedmont Region to the west of the Fall Line is a plateau. Much of the land of the Piedmont has beautiful rolling hills and valleys.

7. The Blue Ridge is a high ridge separating the Piedmont from the Valley and Ridge Province. The billion-year-old igneous and metamorphic rocks of the Blue Ridge are the oldest in the state. The physical region of Virginia known as the Blue Ridge Mountains is located between the Piedmont Region and the Valley and Ridge region. The Blue Ridge Mountains are old, rounded mountains. The highest point in Virginia, Mt. Rogers, is found in these mountains. Receiving much rain, the region is covered with thick forests. Wood is the area's chief resource.

8. The Valley and Ridge province is an area with long parallel ridges and valleys underlain by ancient folded and faulted sedimentary rocks. The folding and faulting of the sedimentary rocks occurred during a collision between Africa and North America. The collision, which occurred in the late Paleozoic era, produced the Appalachian Mountains. This region consists of a series of narrow, elongated, forested knobs and ridges, which are parallel to one another. Most of the ridges rise between 3 and 4 thousand feet The Great Valley is made up of several valleys. The largest of these valleys is the beautiful Shenandoah Valley, located in the northern section of the Great Valley The Shenandoah River winds through the Valley.

9. The Appalachian Plateau has rugged, irregular topography and is underlain by ancient, flat-lying sedimentary rocks. The area is actually a series of plateaus separated by faults and erosional down-cut valleys. Most of Virginia’s coal resources are found in the plateau province. The Appalachian Plateau region of Virginia is sometimes called the "toe of the boot." Its major landform is a plateau which makes this region higher than the Ridge and Valley Region. The average elevation or height of this region is 2000 ft. above sea level. The land of the Appalachian Plateau Region is rugged and covered with forests and valuable coal fields.

10. Igneous metamorphic Igneous Metamorphic Unconsolidated Sediments Sedimentary

11. Resources found in Virginia In Virginia, major rock and mineral resources include coal for energy, gravel and crushed stone for road construction, silica for electronics, zirconium and titanium for advanced metallurgy, and limestone for making concrete.

12. Virginia has experienced an extensive and complex geologic history. Each geologic event has shaped the landscape and left its fingerprint in the form of rocks. By studying these rocks, geologists can better understand how eastern North America formed. A few of the most common rocks found in Virginia are highlighted below. Granite Granite is a plutonic or Igneous Intrusive rock that forms by the slow cooling of trapped magma. As the magma cools, interlocking crystals of feldspar, quartz, and mica form. One example is Old Rag Granite, which forms some of the mountainous peaks of Shenandoah National Park in the Blue Ridge Province, including Old Rag Mountain.

13. Slate is a metamorphic rock that breaks along flat cleavage planes formed by layered mica minerals. It forms as the sedimentary rock shale (composed of sediment such as clay, silt, and mud) is heated and pressurized into metamorphic rock. Slate has been mined in Buckingham County of central Virginia for hundreds of years

14. Quartzite is a metamorphic rock that forms when quartz sandstone is subjected to elevated pressure and temperature during regional metamorphism. Quartzite is a hard rock that is resistant to both chemical and physical weathering. Quartzite occurs in the Blue Ridge and Piedmont provinces. Very pure quartz sandstone, called orthoquartzite, has many of the same physical properties as metamorphic quartzite, but is a sedimentary rock. Orthoquartzite occurs in the Valley and Ridge province.

15. Sandstone is a classic sedimentary rock that is composed of sand sized particles of rock and mineral. Sandstone is most commonly formed in river, beach, or near-shore marine environments. Quartz sandstone (mostly composed of quartz sand) and lithic sandstone (composed of many rock and mineral types) are most common in the Valley and Ridge and Appalachian Plateaus provinces. Arkosic sandstone (mostly composed of quartz and feldspar) occurs in the Mesozoic Basins sub-province of the Piedmont.

16. Coal is an organic sedimentary rock that is composed primarily of fossilized plant matter. Coal in Virginia occurs as layers in sedimentary rocks in the Appalachian Plateaus and Valley and Ridge provinces, and Mesozoic Basin sub-province of the Piedmont. Coal was formed in river, flood plain, and delta environments that existed in Virginia during the late Paleozoic and Mesozoic eras. Virginia coal is a fossil fuel resource that is used primarily to generate electricity and make steel.

17. Gneiss is a metamorphic rock that is formed when igneous, sedimentary, and low-grade metamorphic rock is subjected to relatively high temperatures and pressures during regional metamorphism. These conditions often result in the segregation of minerals into light- and dark-colored bands. The composition, texture, and color of gneiss are variable, due to differences in the original rock type and metamorphic conditions. Gneiss is found in the Piedmont and Blue Ridge Provinces.

18. Conglomerate is a clastic sedimentary rock that contains abundant pebbles and cobbles. These fragments are commonly sub-round to round in shape due to physical weathering. Conglomerate is most commonly formed in river environments. The composition, texture, and color of conglomerate are variable due to differences in the source material and depositional environment. Conglomerate can be found in the Appalachian Plateaus and Valley and Ridge provinces, and the Mesozoic Basins sub- province of the Piedmont

19. Schist is a metamorphic rock that is commonly formed when sedimentary, volcanic igneous, or low-grade metamorphic rock is subjected to moderately high temperatures and pressures during regional metamorphism. These conditions result in the aligned growth of micaceous minerals and give schist a reflective or shiny appearance. The composition, texture, and color of schist are variable, due to differences in the original rock type and metamorphic conditions. Schist is found in the Piedmont and Blue Ridge provinces.

20. Limestone is a chemical or organic sedimentary rock that is composed of lime mud and/or crystalline calcite, and may contain shells and skeletons of fossil marine organisms. Limestone often forms in quiet shallow marine environments. Due to the variety of marine settings in Virginia, limestone is most common in the Valley and Ridge province. Because it is relatively easily dissolved in water, limestone is a common host of caves and caverns in Virginia.

21. Gabbro is an igneous rock that forms from magma that cools slowly deep in the earth’s crust. The texture of gabbro is similar to granite, but the composition is very different. Magma that produces gabbro is rich in iron, magnesium, and calcium, and relatively poor in silica. Common minerals in gabbro are plagioclase feldspar, pyroxene, and olivine. Gabbro occurs in the Piedmont and Blue Ride provinces. Diabase is a rock that is related to gabbro and occurs as dikes and sills in the Piedmont, Blue Ridge, Valley and Ridge provinces, and the Mesozoic Basins sub-province of the Piedmont.

22. Gold is a native element that occurs in Virginia as an accessory mineral in quartz veins. It can also be found at low concentrations in certain types of bedrock. Gold is very dense and resistant to chemical weathering. As a result, gold can sometimes be found near the base of sediment deposits in streams that drain areas containing in-situ gold deposits. Gold has physical properties that make it useful for electronics, jewelry, and dentistry.

23. Minerals of Virginia A wide variety of minerals occur in Virginia. These minerals form the basic building blocks of the rocks that shape the landscape. Minerals exhibit distinctive properties that makes each unique. In Virginia minerals are mined for industrial purposes, collected by enthusiasts, and used for scientific research to help us better understand the Earth. The list of minerals below highlights a few of the most common or popular minerals that are found in Virginia. If you would like more details on the distribution of minerals in our state.

24. Amazonite Kyanite Hemitite Feldspar Mica Calcite Quartz pyrite

29. There are more than 100,000 streams, creeks, or rivers in the watershed, including 150 major rivers. One can reach a Bay tributary in less than 15 minutes from nearly everywhere in the watershed. More than 500 million pounds of seafood is harvested from the Bay every year. The Bay supports 3,600 species of plant and animal life, including more than 300 fish species and 2,700 plant types. The leading threat to the health of the Chesapeake Bay is excess nitrogen and phosphorus pollution that destroys habitat and causes fish kills. Top sources of these pollutants include agriculture, sewage treatment plants, runoff from urban and suburban areas, and air pollution from automobiles, factories, and power plants. Other threats to the Bay's health include sprawl, toxic pollution, and poor fishery management. A few deep troughs running along much of the Bay's length reach up to 174 feet in depth. These troughs are believed to be remnants of the ancient Susquehanna River. Two of the five major North Atlantic ports in the United States—Baltimore and Hampton Roads—are on the Bay. Everything we do on the land—including the use of automobiles, fertilizers, pesticides, toilets, water and electricity—affects our streams, rivers and the Bay.

30. The state of Virginia boasts a spectacular array of fossils—from 540 million year old burrows (Skolithos) to one million year old Mastodon teeth. Our state fossil, Chesapecten jeffersonius, is a large extinct species of scallop that dates to approximately 4.5 million years ago. It was the first fossil ever described in North America and is named after Thomas Jefferson, one of our founding fathers, and an amateur paleontologist. Paleozoic fossils: Cambrian, Ordovician, Silurian, and Devonian sedimentary rocks crop out in the Valley and Ridge and Appalachian Plateau provinces and preserve abundant marine fossils, indicating the presence of extensive, shallow seas. By the Carboniferous (i.e., 350 million years ago), the western part of the state was covered in lush, dense forests of “scale trees” (lycophytes), horsetails, and ferns. The accumulation of organic material in these large coastal swamps eventually produced Virginia’s coal seams. Mesozoic fossils: In the Piedmont province, fossils of dinosaur footprints, freshwater fish, and insects are found in rift basin deposits of the Triassic. In the eastern part of the state, where the sea had not yet retreated, fossil oysters and belemnites have been recovered from a few Cretaceous outcrops. Cenozoic fossils: Dramatic changes in sea level occurred throughout the Cenozoic. The rise and fall of sea level is recorded in the richly fossiliferous rocks of Virginia’s Coastal Plain. Amazing numbers of fossil clams, snails, and sand dollars can be found in these marine rocks, along with fossilized whale bones and shark teeth. Mastodon and mammoth fossils, while not common, can be found in Quaternary sediments that were deposited along rivers and lakes.