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Within the Blue Ridge province, there are two two national parks: the Shenandoah in the northern section and the Great Smoky Mountains in the southern section. The Blue Ridge also contains the Blue Ridge Parkway, a 469-mile long scenic highway that connects the two parks and is located along the ridge crestlines along the Appalachian Trail. [http://www.tec.army.mil/publications/ifsar/lafinal08_01/five/5.1.1_frame.htm]
Within the Blue Ridge province, there are two two national parks: the Shenandoah in the northern section and the Great Smoky Mountains in the southern section. The Blue Ridge also contains the Blue Ridge Parkway, a 469-mile long scenic highway that connects the two parks and is located along the ridge crestlines along the Appalachian Trail. [http://www.tec.army.mil/publications/ifsar/lafinal08_01/five/5.1.1_frame.htm]
==Geography==
==Geography==
Although the term "Blue Ridge" is sometimes applied exclusively to the eastern edge or front range of the Appalachian Mountains, the geological definition of the Blue Ridge province extends westward to the [[Ridge-and-valley Appalachians|Ridge and Valley]] area, encompassing the [[Great Smoky Mountains]], the Great Balsams, the [[Roan Mountain (Roan Highlands)|Roans]], the [[Brushy Mountains (North Carolina)|Brushy Mountains]] (a "spur" of the Blue Ridge) and other [[mountain range]]s.
Although the term "Blue Ridge" is sometimes applied exclusively to the eastern edge or front range of the Appalachian Mountains, the geological definition of the Blue Ridge province extends westward to the [[Ridge-and-valley Appalachians|Ridge and Valley]] area, encompassing the [[Great Smoky Mountains]], the Great Balsams, the [[Roan Mountain (Roan Highlands)|Roans]], the [[Brushy Mountains (North Carolina)|Brushy Mountains]] (a "spur" of the Blue Ridge) and other [[mountain range]]s.
The [[Blue Ridge Parkway]] runs 469 miles (750 km) along the crests of the Southern Appalachians and links two national parks: [[Shenandoah National Park|Shenandoah]] and [[Great Smoky Mountains National Park|Great Smoky Mountains]]. In many places along the parkway, there are [[metamorphic rock|metamorphic]] rocks ([[gneiss]]) with folded bands of light-and dark-colored minerals, which sometimes look like the folds and swirls in a marble cake.
The [[Blue Ridge Parkway]] runs 469 miles (750 km) along the crests of the Southern Appalachians and links two national parks: [[Shenandoah National Park|Shenandoah]] and [[Great Smoky Mountains National Park|Great Smoky Mountains]]. In many places along the parkway, there are [[metamorphic rock|metamorphic]] rocks ([[gneiss]]) with folded bands of light-and dark-colored minerals, which sometimes look like the folds and swirls in a marble cake.
==Geology==
==Geology==
Most of the rocks that form the Blue Ridge Mountains are ancient [[granitic]] [[charnockite]]s, metamorphosed volcanic formations, and sedimentary limestones.Recent studies completed by Richard Tollo, a professor and geologist at the [[George Washington University]], provide greater insight into the petrologic and geochronologic history of the Blue Ridge basement suites. Modern studies have found that the basement geology of the Blue Ridge is made of compositionally unique [[gneiss]]es and [[granite|granitoids]], including orthopyroxene-bearing charnockites. Analyses of [[zircon]] minerals in the granites completed by John Aleinikoff at the [[U.S. Geological Survey]] have provided more detailed emplacement ages.
Most of the rocks that form the Blue Ridge Mountains are ancient [[granitic]] [[charnockite]]s, metamorphosed volcanic formations, and sedimentary limestones.Recent studies completed by Richard Tollo, a professor and geologist at the [[George Washington University]], provide greater insight into the petrologic and geochronologic history of the Blue Ridge basement suites. Modern studies have found that the basement geology of the Blue Ridge is made of compositionally unique [[gneiss]]es and [[granite|granitoids]], including orthopyroxene-bearing charnockites. Analyses of [[zircon]] minerals in the granites completed by John Aleinikoff at the [[U.S. Geological Survey]] have provided more detailed emplacement ages.
Many of the features found in the Blue Ridge and documented by Tollo and others have confirmed that the rocks exhibit many similar features in other North American [[Grenville orogeny|Grenville-age]] [[terrane]]s. The lack of a calc-alkaline affinity and zircon ages less than 1,200 [[Annum|Ma]] suggest that Blue Ridge are unique from the [[Adirondack Mountains|Adirondacks]], [[Green Mountains]], and possibly the [[New York-New Jersey Highlands]]. The [[Petrology|petrologic]] and [[Geochronology|geochronologic]] data suggest that the Blue Ridge basement is a composite orogenic crust that was emplaced during several episodes from a crustal magma source. Field relationships further illustrate that rocks emplaced prior to 1,078-1,064 Ma preserve deformational features. Those emplaced post-1,064 Ma generally have a massive texture and missed the main episode of Mesoproterozoic compression. [http://gsa.confex.com/gsa/2004NE/finalprogram/abstract_69016.htm]
Many of the features found in the Blue Ridge and documented by Tollo and others have confirmed that the rocks exhibit many similar features in other North American [[Grenville orogeny|Grenville-age]] [[terrane]]s. The lack of a calc-alkaline affinity and zircon ages less than 1,200 [[Annum|Ma]] suggest that Blue Ridge are unique from the [[Adirondack Mountains|Adirondacks]], [[Green Mountains]], and possibly the [[New York-New Jersey Highlands]]. The [[Petrology|petrologic]] and [[Geochronology|geochronologic]] data suggest that the Blue Ridge basement is a composite orogenic crust that was emplaced during several episodes from a crustal magma source. Field relationships further illustrate that rocks emplaced prior to 1,078-1,064 Ma preserve deformational features. Those emplaced post-1,064 Ma generally have a massive texture and missed the main episode of Mesoproterozoic compression. [http://gsa.confex.com/gsa/2004NE/finalprogram/abstract_69016.htm]
==History==
==History==
The English who settled [[Virginia]] in the early 1600s recorded that the native [[Powhatan]] name for the Blue Ridge was ''Quirank''.
The English who settled [[Virginia]] in the early 1600s recorded that the native [[Powhatan]] name for the Blue Ridge was ''Quirank''.