Hillsboro is a rural town in Loudoun County, Virginia, United States. The population was 114 at the 2020 census.
The geology of the Appalachians dates back more than 1.2 billion years to the Mesoproterozoic era when two continental cratons collided to form the supercontinent Rodinia, 500 million years prior to the development of the range during the formation of Pangea. The rocks exposed in today's Appalachian Mountains reveal elongate belts of folded and thrust faulted marine sedimentary rocks, volcanic rocks, and slivers of ancient ocean floor—strong evidences that these rocks were deformed during plate collision. The birth of the Appalachian ranges marks the first of several mountain building plate collisions that culminated in the construction of Pangea with the Appalachians and neighboring Anti-Atlas mountains near the center. These mountain ranges likely once reached elevations similar to those of the Alps and the Rocky Mountains before they were eroded.
The geology of the Grand Teton area consists of some of the oldest rocks and one of the youngest mountain ranges in North America. The Teton Range, partly located in Grand Teton National Park, started to grow some 9 million years ago. An older feature, Jackson Hole, is a basin that sits aside the range.
The Alleghanian orogeny or Appalachian orogeny is one of the geological mountain-forming events that formed the Appalachian Mountains and Allegheny Mountains. The term and spelling Alleghany orogeny was originally proposed by H.P. Woodward in 1957.
Catoctin Mountain, along with the geologically associated Bull Run Mountains, forms the easternmost mountain ridge of the Blue Ridge Mountains, which are in turn a part of the Appalachian Mountains range. The ridge runs northeast–southwest for about 50 miles (80 km) departing from South Mountain near Emmitsburg, Maryland, and running south past Leesburg, Virginia, where it disappears into the Piedmont in a series of low-lying hills near New Baltimore, Virginia. The ridge forms the eastern rampart of the Loudoun and Middletown valleys.
The Bull Run Mountains are a mountain range of the Blue Ridge Mountains in northern Virginia in the United States. Located approximately 20 miles (32 km) east of the main chain, across the Loudoun Valley. The Bull Run Mountains, together with Catoctin Mountain in Virginia and Maryland, make up the easternmost front of the Blue Ridge.
Rockfish Gap is a wind gap located in the Blue Ridge Mountains between Charlottesville and Waynesboro, Virginia, United States, through Afton Mountain, which is frequently used to refer to the gap.
Catoctin Creek is a 14.1-mile-long (22.7 km) tributary of the Potomac River in Loudoun County, Virginia, with a watershed of 59,000 acres (240 km2). Agricultural lands make up 67 percent and forests 30 percent of Catoctin Creek's watershed. It is the main drainage system for the northern Loudoun Valley, including all of the Catoctin Valley.
Blue Ridge Mountain, also known as Blue Mountain, is the colloquial name of the westernmost ridge of the Blue Ridge Mountains in northern Virginia and the Eastern Panhandle of West Virginia. The Appalachian Trail traverses the entire length of the mountain along its western slope and crest.
The Environment of West Virginia encompasses terrain and ecosystems ranging from plateaus to mountains. Most of West Virginia lies within the Appalachian mixed mesophytic forests ecoregion, while the higher elevations along the eastern border and in the panhandle lie within the Appalachian-Blue Ridge forests.
The Loudoun Valley is a small, but historically significant valley in the Blue Ridge Mountains located in Loudoun County in Northern Virginia in the United States.
Between the Hills is a small valley in northwest Loudoun County, Virginia, distinct from, but associated with, the greater Loudoun Valley.
Loudoun County, Virginia, was destined to be an area of significant military activity during the American Civil War. Located on Virginia's northern frontier, the Potomac River, Loudoun County became a borderland after Virginia's secession from the Union in early 1861. Loudoun County's numerous Potomac bridges, ferries and fords made it an ideal location for the Union and Confederate armies to cross into and out of Virginia. Likewise, the county's several gaps in the Blue Ridge Mountains that connected the Piedmont to the Shenandoah Valley and Winchester were of considerable strategic importance. The opposing armies would traverse the county several times throughout the war leading to several small battles, most notably the Battle of Ball's Bluff.
South Mountain is the northern extension of the Blue Ridge Mountain range into Maryland and Pennsylvania. From the Potomac River near Knoxville, Maryland in the south to Dillsburg, Pennsylvania in York County, Pennsylvania in the north, the 70-mile-long (110 km) range separates the Hagerstown and Cumberland valleys from the Piedmont regions of the two states.
Virginia State Route 9 is a primary state highway in the U.S. state of Virginia. Known as Charles Town Pike, the state highway runs 13.08 miles (21.05 km) from the West Virginia state line near Mechanicsville, where the highway continues west as West Virginia Route 9, east to SR 7 and SR 7 Business in Paeonian Springs. SR 9 is the main east–west highway of northwestern Loudoun County, connecting Leesburg with Hillsboro and the West Virginia cities of Charles Town and Martinsburg. As a result, the state highway and its West Virginia continuation are a major, overburdened commuter route between the Eastern Panhandle of West Virginia and Washington, D.C.
The Geology of Pennsylvania consists of six distinct physiographic provinces, three of which are subdivided into different sections. Each province has its own economic advantages and geologic hazards and plays an important role in shaping everyday life in the state. From the southeast corner to the northwest corner of the state, they include: the Atlantic Plain Province, the Piedmont Province, the New England Province, the Ridge and Valley Province, the Appalachain Province, and the Central Lowlands Province.
West Virginia's geologic history stretches back into the Precambrian, and includes several periods of mountain building and erosion. At times, much of what is now West Virginia was covered by swamps, marshlands, and shallow seas, accounting for the wide variety of sedimentary rocks found in the state, as well as its wealth of coal and natural gas deposits. West Virginia has had no active volcanism for hundreds of millions of years, and does not experience large earthquakes, although smaller tremors are associated with the Rome Trough, which passes through the western part of the state.
Humpback Rocks is a massive greenstone outcropping near the peak of Humpback Mountain in the Blue Ridge Mountains of Augusta County and Nelson County, Virginia, United States, with a summit elevation of 3,080 feet (940 m). The rock formation is so named for the visual effect of a "hump" it creates on the western face of the mountain.
The geology of Virginia began to form at least 1.8 billion years ago. The oldest rocks in the state were metamorphosed during the Grenville orogeny, a mountain-building event beginning 1.2 billion years ago in the Proterozoic, which obscured older rocks. Throughout the Proterozoic and Paleozoic, Virginia experienced igneous intrusions, carbonate and sandstone deposition, and a series of other mountain-building events which defined the terrain of the inland parts of the state. The closing of the Iapetus Ocean formed the supercontinent Pangaea, and created additional small landmasses, some of which are now hidden beneath thick Atlantic Coastal Plain sediments. The region subsequently experienced the rifting open of the Atlantic ocean in the Mesozoic, the development of the Coastal Plain, isolated volcanism, and a series of marine transgressions that flooded much of the area. Virginia has extensive deposits of coal, oil, and natural gas, as well as deposits of other minerals and metals, including vermiculite, kyanite and uranium.
Matchless Mountain is a high mountain summit in the Elk Mountains range of the Rocky Mountains of North America. The 12,389-foot (3,776 m) mountain is located in Gunnison National Forest, 18.3 miles (29.4 km) east-southeast of the Town of Crested Butte in Gunnison County, Colorado, United States.
