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{{Short description|Meeting point of uplands and coastal plain}}
{{Short description|Meeting point of uplands and coastal plain}}
{{About|the concept in geomorphology|fall line as a gradient|Fall line (topography)|other uses|Fall line (disambiguation)}}
{{About|the concept in geomorphology|fall line as a gradient|Fall line (topography)|other uses|Fall line (disambiguation)}}
A '''fall line''' (or '''fall zone''') is the area where an upland region and a [[coastal plain]] meet and is noticeable especially the place rivers cross it, with resulting [[rapids]] or [[waterfall]]s. The uplands are relatively hard [[Basement (geology)|crystalline basement rock]], and the [[coastal plain]] is softer [[sedimentary rock]].<ref name=schneider>{{cite book |last= Schneider |first= Craig W. |author2=Richard B. Searles |title= Seaweeds of the southeastern United States: Cape Hatteras to Cape Canaveral |year= 1991 |publisher= Duke University Press |isbn= 978-0-8223-1101-0 |pages= 5–7 |url= https://books.google.com/books?id=gWA5kv_0g3cC&pg=PA5 |access-date= 17 November 2010}}</ref> A fall line often will recede upstream as a river cuts out the uphill dense material, forming "c"-shaped waterfalls and exposing bedrock [[shoals]]. Due to these features, riverboats typically cannot travel any further inland without [[portage|portaging]], unless [[Lock (water navigation)|locks]] are built. The rapid change of elevation of the water and resulting energy release make the fall line a good location for [[water mill]]s, [[grist mill]]s, and [[sawmill]]s. Seeking a [[head of navigation]] with a ready supply of water power, people have long made settlements where rivers cross a fall line.
A '''fall line''' (or '''fall zone''') is the area where an upland region and a [[coastal plain]] meet and is especially noticeable at the place rivers cross it, with resulting [[rapids]] or [[waterfall]]s. The uplands are relatively hard [[Basement (geology)|crystalline basement rock]], and the [[coastal plain]] is softer [[sedimentary rock]].<ref name=schneider>{{cite book |last= Schneider |first= Craig W. |author2=Richard B. Searles |title= Seaweeds of the southeastern United States: Cape Hatteras to Cape Canaveral |year= 1991 |publisher= Duke University Press |isbn= 978-0-8223-1101-0 |pages= 5–7 |url= https://books.google.com/books?id=gWA5kv_0g3cC&pg=PA5 |access-date= 17 November 2010}}</ref> A fall line often will recede upstream as a river cuts out the uphill dense material, forming "c"-shaped waterfalls and exposing bedrock [[shoals]]. Due to these features, riverboats typically cannot travel any further inland without [[portage|portaging]], unless [[Lock (water navigation)|locks]] are built. The rapid change of elevation of the water and resulting energy release make the fall line a good location for [[water mill]]s, [[grist mill]]s, and [[sawmill]]s. Seeking a [[head of navigation]] with a ready supply of water power, people have long made settlements where rivers cross a fall line.


==Geography==
==Geography==
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The slope of rivers crossing fall zones affected settlement patterns. For example, the fall line represents the inland limit of navigation of many rivers. Numerous cities along a fall line grew as a result of demand for transferring people and goods between land-based and water-based transportation at that place.<ref name=UGA>{{cite web |url=http://www.gly.uga.edu/railsback/1122EUSMISR.html |title=The Fall Line and major cities of the Eastern U.S.}}</ref>
The slope of rivers crossing fall zones affected settlement patterns. For example, the fall line represents the inland limit of navigation of many rivers. Numerous cities along a fall line grew as a result of demand for transferring people and goods between land-based and water-based transportation at that place.<ref name=UGA>{{cite web |url=http://www.gly.uga.edu/railsback/1122EUSMISR.html |title=The Fall Line and major cities of the Eastern U.S.}}</ref>


{{Globalize|section|USA|2name=the United States|date=November 2016}}
==Examples==


===North American Atlantic Seaboard Fall Line===
===Atlantic Seaboard Fall Line===
{{Main|Atlantic Seaboard Fall Line}}
{{main|Atlantic Seaboard Fall Line}}


{{GeoGroupTemplate|align=left}}
The Atlantic Seaboard Fall Line, is a {{convert|900|mi|km|adj=on|abbr=off|order=flip}} [[escarpment]] where the [[Piedmont (United States)|Piedmont]] and [[Atlantic Coastal Plain]] meet in the eastern [[United States]].<ref name=freitag>{{cite book |last= Freitag |first= Bob |author2=Susan Bolton|author3=Frank Westerlund|author4=Julie Clark |title= Floodplain Management: A New Approach for a New Era |year= 2009 |publisher= Island Press |isbn= 978-1-59726-635-2 |page= 77 |url= https://books.google.com/books?id=e1lr3gQiO8gC&pg=PA77 |access-date= 17 November 2010}}</ref> Much of the Atlantic Seaboard fall line passes through areas where no evidence of [[Fault (geology)|faulting]] is present.
 
The '''Atlantic Seaboard Fall Line''', or '''Fall Zone''', is a {{convert|900|mi|km|adj=on|abbr=off|order=flip}} [[escarpment]] where the [[Piedmont (United States)|Piedmont]] and [[Atlantic Coastal Plain]] meet in the eastern [[United States]].<ref name=freitag>{{cite book |last= Freitag |first= Bob |author2=Susan Bolton|author3=Frank Westerlund|author4=Julie Clark |title= Floodplain Management: A New Approach for a New Era |year= 2009 |publisher= Island Press |isbn= 978-1-59726-635-2 |page= 77 |url= https://books.google.com/books?id=e1lr3gQiO8gC&pg=PA77 |access-date= 17 November 2010}}</ref> Much of the Atlantic Seaboard fall line passes through areas where no evidence of [[Fault (geology)|faulting]] is present.


The fall line marks the geologic boundary of hard metamorphosed terrain—- the product of the [[Taconic orogeny]]—- and the sandy, relatively flat outwash plain of the upper continental shelf, formed of unconsolidated [[Cretaceous]] and [[Tertiary period|Tertiary]] [[sediment]]s. Examples of the Fall Zone include the Potomac River's [[Little Falls (Potomac River)|Little Falls]] and the rapids in [[Richmond, Virginia]], where the [[James River]] falls across a series of rapids down to the tidal estuary of the James River.
The fall line marks the geologic boundary of hard metamorphosed terrain—- the product of the [[Taconic orogeny]]—- and the sandy, relatively flat outwash plain of the upper continental shelf, formed of unconsolidated [[Cretaceous]] and [[Tertiary period|Tertiary]] [[sediment]]s. Examples of the Fall Zone include the Potomac River's [[Little Falls (Potomac River)|Little Falls]] and the rapids in [[Richmond, Virginia]], where the [[James River]] falls across a series of rapids down to the tidal estuary of the James River.
 
<!-- Add further places to the main article. Don't create a list here -->
Before navigation improvements such as locks, the fall line was often the [[wikt:head of navigation|head of navigation]] of rivers due to rapids and waterfalls, like the [[Little Falls (Potomac River)|Little Falls]] of the [[Potomac River]]. Numerous cities were founded at the intersection of rivers and the fall line. [[U.S. Route 1]] links many of the fall line cities.
 
In the USA, Mid-Atlantic and Southern fall line cities include:
*[[Paterson, New Jersey]], on the [[Passaic River]]{{Citation needed|date=January 2017}}
*[[Trenton, New Jersey]], on the [[Delaware River]]<ref name="freitag" />
*[[Philadelphia|Philadelphia, Pennsylvania]], on the [[Schuylkill River]]<ref name=shamsi>{{cite book |last= Shamsi |first= Nayyar |title= Encyclopaedia of Political Geography |year= 2006 |publisher= Anmol Publications |isbn= 978-81-261-2406-0 |pages= 92–93 |url= https://books.google.com/books?id=4Z2Kh7ELI0oC&pg=PA92 |access-date= 17 November 2010}}</ref><ref name="Dunkerly">{{cite book|last1=Dunkerly|first1=Robert|last2=Boland|first2=Irene|title=Eutaw Springs|date=2017|publisher=The University of South Carolina Press|location=Columbia|isbn=9781611177589|pages=24}}</ref>
*[[Wilmington, Delaware]], on [[Brandywine Creek (Christina River)|Brandywine Creek]]<ref>{{cite web |url=http://www.dgs.udel.edu/delaware-geology/summary-geologic-history-delaware |title= A Summary of the Geologic History of Delaware |publisher= The Delaware Geological Survey |access-date= 25 January 2017}}</ref>
*[[Baltimore|Baltimore, Maryland]], on the [[Jones Falls]], [[Gunpowder Falls]] and [[Gwynns Falls]]<ref>{{cite web |url= http://www.mgs.md.gov/geology/ |title= Maryland Geology |publisher= Maryland Geological Society |access-date= 25 January 2017}}</ref>
*[[Washington, D.C.]], on the [[Potomac River]]<ref name=vaplaces>{{cite web |url= http://www.virginiaplaces.org/regions/fallshape.html |title= Geology of the Fall Line |publisher= Virginia Places |access-date= 25 January 2017}}</ref><ref name="Dunkerly" />
*[[Fredericksburg, Virginia]], on the [[Rappahannock River]]<ref name=vaplaces />
*[[Hanover, Virginia]], on the [[North Anna River]]{{Citation needed|date=January 2017}}
*[[Richmond, Virginia]], on the [[James River]]<ref name=vaplaces/><ref name="Dunkerly" />
*[[Petersburg, Virginia]], on the [[Appomattox River]]<ref name=vaplaces/>
*[[Weldon, North Carolina]], and [[Roanoke Rapids, North Carolina]], on the [[Roanoke River]]<ref name=ncpedia>{{cite web |url= http://www.ncpedia.org/fall-line |title= Fall Line |publisher= NCpedia |access-date= 25 January 2017}}</ref>
*[[Rocky Mount, North Carolina]], on the [[Tar River]]
*[[Fayetteville, North Carolina]], on the [[Cape Fear River]]<ref name=ncpedia/>
*[[Camden, South Carolina]], on the [[Wateree River]]<ref name="Dunkerly" />
*[[Columbia, South Carolina]], on the [[Congaree River]]<ref name=UGA/><ref name="Dunkerly" />
*[[Augusta, Georgia]], on the [[Savannah River]]<ref name=georgiaency>{{cite web |url= http://www.georgiaencyclopedia.org/nge/Article.jsp?id=h-721 |title= Fall Line |publisher= The New Georgia Encyclopedia |access-date= 17 October 2011}}</ref><ref name="Dunkerly" />
*[[Milledgeville, Georgia]], on the [[Oconee River]]<ref name=georgiaency/>
*[[Macon, Georgia]], on the [[Ocmulgee River]]<ref name=georgiaency/>
*[[Columbus, Georgia]], on the [[Chattahoochee River]]<ref name=freitag/>
*[[Tallassee, Alabama]], on the [[Tallapoosa River]]<ref name=alabamaency>{{cite web |url= http://www.encyclopediaofalabama.org/article/h-1618 |title= Fall Line |publisher= Encyclopedia of Alabama |access-date= 25 January 2017}}</ref>
*[[Wetumpka, Alabama]], on the [[Coosa River]]<ref name=alabamaency/>
*[[Tuscaloosa, Alabama]], on the [[Black Warrior River]]<ref name=alabamaency/>


===Canada===
===Canada===
The [[Laurentian Upland]] forms a long scarp line where it meets the [[Great Lakes–St. Lawrence Lowlands]]. Along this line, numerous rivers have carved falls and canyons (listed east to west):
The [[Laurentian Upland]] forms a long scarp line where it meets the [[Great Lakes–St. Lawrence Lowlands]], just north of the [[Saint Lawrence River|St. Lawrence]] river and estuary. Along this line, numerous rivers have carved falls and canyons (listed east to west):
*[[Saint Anne Falls]] and [[Canyon Sainte-Anne]] ([[Sainte-Anne-du-Nord River|River Sainte-Anne-du-Nord]])
*[[Saint Anne Falls]] and [[Canyon Sainte-Anne]] ([[Sainte-Anne-du-Nord River|River Sainte-Anne-du-Nord]])
*Chaudron à Gaudreault ([[Rivière aux Chiens (Côte-de-Beaupré)|Rivière aux Chiens]])
*Chaudron à Gaudreault ([[Rivière aux Chiens (Côte-de-Beaupré)|Rivière aux Chiens]])
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==See also==
==See also==
*[[Geologic map of Georgia (U.S. state)]]
*[[Geologic map of Georgia (U.S. state)]]
*[[Spring line settlement]]
*[[Spring line settlement]] - the analogous concept where access to fresh water is more important than navigation or power


==References==
==References==

Latest revision as of 01:14, 3 September 2025

Template:Short description Script error: No such module "about". A fall line (or fall zone) is the area where an upland region and a coastal plain meet and is especially noticeable at the place rivers cross it, with resulting rapids or waterfalls. The uplands are relatively hard crystalline basement rock, and the coastal plain is softer sedimentary rock.[1] A fall line often will recede upstream as a river cuts out the uphill dense material, forming "c"-shaped waterfalls and exposing bedrock shoals. Due to these features, riverboats typically cannot travel any further inland without portaging, unless locks are built. The rapid change of elevation of the water and resulting energy release make the fall line a good location for water mills, grist mills, and sawmills. Seeking a head of navigation with a ready supply of water power, people have long made settlements where rivers cross a fall line.

Geography

File:Bulletin 426 Fig 2 Fall Line.jpg
Diagram showing the Fall Line. USGS figure.

The slope of rivers crossing fall zones affected settlement patterns. For example, the fall line represents the inland limit of navigation of many rivers. Numerous cities along a fall line grew as a result of demand for transferring people and goods between land-based and water-based transportation at that place.[2]

Examples

Atlantic Seaboard Fall Line

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The Atlantic Seaboard Fall Line, is a Script error: No such module "convert". escarpment where the Piedmont and Atlantic Coastal Plain meet in the eastern United States.[3] Much of the Atlantic Seaboard fall line passes through areas where no evidence of faulting is present.

The fall line marks the geologic boundary of hard metamorphosed terrain—- the product of the Taconic orogeny—- and the sandy, relatively flat outwash plain of the upper continental shelf, formed of unconsolidated Cretaceous and Tertiary sediments. Examples of the Fall Zone include the Potomac River's Little Falls and the rapids in Richmond, Virginia, where the James River falls across a series of rapids down to the tidal estuary of the James River.

Canada

The Laurentian Upland forms a long scarp line where it meets the Great Lakes–St. Lawrence Lowlands, just north of the St. Lawrence river and estuary. Along this line, numerous rivers have carved falls and canyons (listed east to west):

The River Jacques-Cartier and River Saint-Maurice lack such noticeable features because they cross the scarp through U-shaped valleys. The falls of the lower Saint-Maurice (as well as those of the River Beauport, in Quebec City) are due to the fluvial terraces of the Saint Lawrence river rather than the Laurentian Scarp.

See also

References

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  3. ↑ Script error: No such module "citation/CS1".

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External links

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