View source for Niagara Escarpment

{{short description|Escarpment in Canada and the United States}}
[[File:Niagara Escarpment map.png|thumb|upright=1.6|Niagara Escarpment (in red)]]
[[File:Niagara-Escarpment-Rattlesnake.jpg|thumb|upright=1.6|[[Rattlesnake Point (Canada)|Rattlesnake Point]] near [[Milton, Ontario]]]]
[[File:DSC 8739 (10596155586).jpg|thumb|The [[Niagara River]] has carved the [[Niagara Gorge]] through the Niagara Escarpment over thousands of years.]]
The '''Niagara Escarpment''' is an approximately {{convert|1050|km|mile|adj=mid|-long}} discontinuous, arc-shaped but generally northward-facing [[escarpment]], or [[cuesta]], in [[Canada]] and the [[United States]]. The [[escarpment]] begins south of Lake Ontario and circumscribes the top of the [[Great Lakes Basin]] running from [[New York (state)|New York]] through [[Ontario]], [[Upper Peninsula of Michigan|Michigan]], and [[Wisconsin]]. The escarpment is the cliff over which the [[Niagara River]] plunges at [[Niagara Falls]], for which it is named. 
 
The escarpment is a [[United Nations Educational, Scientific and Cultural Organization|UNESCO]] World [[Niagara Escarpment Biosphere Reserve|Biosphere Reserve]]. The reserve has the oldest forest ecosystem and trees in eastern North America.<ref>{{cite book |last=Kelly |first=Peter |date=2007-05-31 |title=The Last Stand: A Journey Through the Ancient Cliff-Face Forest of the Niagara Escarpment |publisher=Natural Heritage |edition=1st |isbn=978-1-897045-19-0 |url=https://www.amazon.ca/gp/product/1897045190/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&camp=15121&creative=330641&creativeASIN=1897045190&linkCode=as2 |access-date= 2018-04-04}}</ref>

The escarpment is not a [[Fault (geology)|fault line]] but the result of unequal [[erosion]]. The cliff-forming rock exposed along the escarpment is a belt of limestone and dolomite of the [[Lockport Formation]] of [[Silurian]] age. The Niagara Escarpment is the most prominent of several escarpments formed in the bedrock of the [[Great Lakes Basin]]. For example, the [[Onondaga Formation]], which runs in a parallel outcrop belt just to the south of the Lockport Formation through [[western New York]] and [[southern Ontario]], forms a separate escarpment. The Niagara Escarpment traces, and in part shapes, the individual basins and landforms of [[Lake Ontario]], [[Lake Huron]], and [[Lake Michigan]].

In [[Rochester, New York]], the [[Genesee River]] flows through the city in three waterfalls over the scarp face. The escarpment thence runs westward to the Niagara River, forming a deep gorge north of Niagara Falls, which itself cascades over the scarp face. In [[Southern Ontario]], it spans the [[Niagara Peninsula]], closely following the Lake Ontario shore through the cities of [[St. Catharines, Ontario|St. Catharines]] and [[Hamilton, Ontario|Hamilton]], where it takes a sharp turn north in the town of [[Milton, Ontario|Milton]] toward [[Georgian Bay]]. It then follows the Georgian Bay shore northwestwards to form the spine of the [[Bruce Peninsula]] and [[Manitoulin Island]], as well as several smaller islands in northern Lake Huron, where it turns westwards into the [[Upper Peninsula]] of northern Michigan, south of [[Sault Ste. Marie, Michigan|Sault Ste. Marie]]. It extends down the [[Garden Peninsula]] and [[Potawatomi Islands]] into Wisconsin following the [[Door Peninsula]] and then continues more inland from the western coast of Lake Michigan until ending in the southeastern corner of [[Dodge County, Wisconsin|Dodge County]].<ref>John Luczaj, [http://wgnhs.uwex.edu/pubs/gs22a01/ "Geology of the Niagara Escarpment in Wisconsin"]</ref>

==Formation==
{{stack|
[[File:Niagara-Escarpment-Winter-IMG 0626.JPG|right|thumb|275px|Niagara Escarpment in [[Grimsby, Ontario]] from about 1060 metres (3,500 feet) above sea level]]
[[File:Bruce-Trail-bmountain.jpg|thumb|right|275px|A section of escarpment cliff, seen from the Bruce Trail in Ontario]]
[[File:NiagaraEscarpmentOutcroppings LakeMichiganShore.jpg|thumb|right|275px|[[Outcrop]]ping of the escarpment in [[Door County, Wisconsin]] approximately 10 feet (3&nbsp;m) from [[Lake Michigan]]]]
[[File:Niagara Escarpment from above Rattlesnake Point, Milton, Ontario.jpg|thumb|275px|Niagara Escarpment from above Rattlesnake Point, Milton, Ontario]]
[[File:Niagara-Escarpment-Dodge-Co.jpg|thumb|right|275px|alt=Exposure at Dodge County Ledge Park, Wi|Exposure of the escarpment at Dodge County Ledge Park, [[Dodge County, Wisconsin]].]]

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Study of rock exposures and drillholes demonstrates that no displacement of the rock layers occurs at the escarpment, which is not a [[Fault (geology)|fault line]] but the result of unequal [[erosion]]. The escarpment's [[caprock]] is [[Dolomite (mineral)|dolomitic]] [[limestone]], also known as [[Dolomite (rock)|dolostone]], which is more resistant and overlies weaker, more easily eroded [[shale]] as a [[weathering]]-resistant "cap". The escarpment formed over millions of years through a process of differential erosion of these rocks of different hardnesses. Through time the soft rocks weather away or erode by the action of streams. The gradual removal of the soft rocks undercuts the resistant caprock, leaving a cliff or escarpment. The erosional process is most readily seen at [[Niagara Falls]], where the river has quickened the process. It can also be seen at the three [[Genesee River|waterfalls of the Genesee River]] at [[Rochester, New York|Rochester]] (additional resistant rock layers make more than one escarpment in some places). Also, in some places thick glacial deposits, such as the [[Oak Ridges Moraine]], conceal the Niagara Escarpment, such as north of [[Georgetown, Ontario]], where it actually continues under [[glacial till]] and reappears farther north.{{Cn|date=September 2021}}

The dolomite cap was laid down as sediment on the floor of a marine environment. In Michigan, behind (south of) the escarpment, the ''cuesta'' capstone slopes gently to form a [[Michigan Basin|wide basin]], the floor of an [[Ordovician]]-Silurian-age tropical sea. (The escarpment is essentially the remnant shoreline of that sea.) There the constant deposition of minute shells and fragments of biologically-generated [[calcium carbonate]], mixed with sediment washed in by erosion of the virtually lifeless landmasses, eventually formed a limestone layer. During the Silurian period, some magnesium substituted for some of the calcium in the carbonates, slowly forming harder [[Dolomite (rock)|dolomite]] layers in the same fashion. This dolomite basin contains Lakes Michigan, Huron, and Erie. Worldwide sea levels were at their all-time maximum in the Ordovician; as the sea retreated, erosion inevitably began.<ref>{{cite web|url=http://www.uwgb.edu/dutchs/GeologyWisconsin/niagesc.htm|title=The Niagara Escarpment|work=uwgb.edu|access-date=2010-09-07|archive-url=https://web.archive.org/web/20100604132605/http://www.uwgb.edu/dutchs/GeologyWisconsin/niagesc.htm|archive-date=2010-06-04|url-status=dead}}</ref>

==Human geography==
{{More citations needed|section|date=September 2021}}
The escarpment was a major obstacle in the construction of the [[Erie Canal]] in New York and was traversed by a series of locks; the community which grew up at the site thus became known as [[Lockport (city), New York|Lockport, New York]].<ref>{{Cite book|title=Lockport : Historic jewel of the Erie Canal|last=L.|first=Riley, Kathleen|date=2005-01-01|publisher=Arcadia|isbn=978-0-7385-2477-1|pages=34|oclc=65537681}}</ref>

The [[Welland Canal]] allows ships to traverse the escarpment between [[Lake Erie]] and Lake Ontario on the Niagara Peninsula of Ontario.<ref>{{Cite book|title=The Welland Canals and their communities : engineering, industrial, and urban transformation|last=Jackson|first=John N.|date=1997-01-01|publisher=University of Toronto Press|isbn=978-0-8020-0933-3|oclc=803101574}}</ref> The canal also allowed [[Sea Lamprey]], an invasive species native to Northern Atlantic Ocean, to enter Lake Erie and became a concern for the lake's ecosystem.<ref>{{cite web | url=https://lakeerieliving.com/articles/2023-julyaugust/sea-lampreys-escalate-in-lake-erie/#:~:text=Lampreys%20are%20native%20to%20the,access%20to%20the%20Great%20Lakes | title=Sea Lampreys Escalate in Lake Erie }}</ref> 

In southern Ontario, the [[Bruce Trail]] runs the length of the escarpment from [[Queenston, Ontario|Queenston]] on the Niagara River to [[Tobermory, Ontario|Tobermory]] on the Bruce Peninsula. [[Ontario Highway 401|Highway 401]], Canada's busiest, also crosses the Niagara Escarpment, beginning its long descent through rolling hills, farmland, and towns west of Milton. Rock exposed on the face of the escarpment can be seen along [[Ontario Highway 26|Highway 26]] from [[Owen Sound]] eastwards towards [[Meaford, Ontario]].

[[Hamilton, Ontario]] is on the escarpment in such a way that the north end of the city is below and the south part above. Commonly referred to as "The Mountain" by its residents, many roads or "mountain accesses" join the urban core below with the suburban expansion above. From 1892 to 1936, the [[Hamilton Incline Railway]] transported people up and down "The Mountain."

[[High Cliff State Park]] in Wisconsin shows how modern and prehistoric humans used the escarpment for not only cultural reasons, but economic gains, as well. A number of different animal and geometric [[effigy mound]]s and the remains of an early 20th-century limestone quarry and kiln are within the park.

The [[Topographic relief|relief]] and exposed edge are used by several [[wind farm]]s stretching from [[Pipe, Wisconsin|Pipe]] to [[Brownsville, Wisconsin|Brownsville]] in Wisconsin. Wind speeds average 18&nbsp;mph (about 29&nbsp;km/h) along this stretch.

The Niagara Escarpment is a prominent Wisconsin feature in Dodge County, southwest of Fond du Lac, Wisconsin; it is known there as "The Ledge" and is in Ledge County Park between Horicon and Mayville, Wisconsin.<ref>Joanne Kluessendorf, [http://dnr.wi.gov/wnrmag/2010/10/ledge.htm "A look at The Ledge"], Wisconsin Natural Resources magazine, October 2010.</ref> Some local organizations take their name from it, including The Ledgers, the sports teams at [[St. Mary Springs High School|St. Mary's Springs Academy]], which is perched on the side of the escarpment.

Many resorts and [[ski country|ski areas]] in Ontario, Michigan, Wisconsin, and New York are along the escarpment.

==Vineyard land==
[[Niagara County, New York]], near the eastern end of the escarpment, is the site of the {{convert|18,000|acre|ha|0}} [[Niagara Escarpment AVA]] ([[American Viticultural Area]]).<ref>[http://a257.g.akamaitech.net/7/257/2422/01jan20051800/edocket.access.gpo.gov/2005/pdf/05-17759.pdf Federal Register / Vol. 70, No. 173 / Thursday, September 8, 2005 / Rules and Regulations, page 53300 – Alcohol and Tobacco Tax and Trade Bureau 27 CFR Part 9 [T.D. TTB–33; Re: Notice No. 33] RIN 1513–AA97. Establishment of the Niagara Escarpment Viticultural Area (2004R–589P)</ref> Wines produced in this region include traditional [[grape varieties]] such as [[Merlot]], [[Cabernet Franc]], [[Cabernet Sauvignon]], [[Chardonnay]], and [[Riesling]], and [[fruit wines]].

Ontario's [[Niagara Peninsula]] is the site of the largest [[Canadian wine|wine-producing]] [[appellation]] (region) in Canada. Cool-climate varieties such as Riesling, Chardonnay, Gamay Noir, Pinot Noir, and Cabernet Franc are among the more than 30 [[varietal]]s produced across {{convert|13,600|ha|acre|0}}. Three subappellations lie along the [[Bench (geology)|benchlands]] of the Niagara Escarpment: [[Short Hills Bench]], [[Twenty Mile Bench]], and [[Beamsville Bench]].<ref>{{cite web|url=http://www.vqaontario.com/Appellations/NiagaraPeninsula |title=VQA Ontario · The Appellations · Niagara Peninsula |publisher=Vqaontario.com |access-date=2016-05-07}}</ref>

Northeastern Wisconsin, at the western end of the escarpment, is the site of the {{convert|3,800|sqmi|km2|abbr=on}} [[Wisconsin Ledge AVA]].<ref>{{cite web|url=http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr;sid=bff700d0bbb2a632948b70fe7e91d7d4;rgn=div5;view=text;node=27%3A1.0.1.1.7;idno=27;cc=ecfr#27:1.0.1.1.7.3.41.204 |title=eCFR — Code of Federal Regulations |publisher=Ecfr.gov |access-date=2016-05-07}}</ref> Most of the region's vineyards lie upon the escarpment's eastern-facing slope that rises gently upward from the shores of Lake Michigan to the top of the Ledge, before dropping sharply off into Green Bay, and benefit greatly from constant air movement from Lake Michigan, which stores warmth during the summer. The presence of the lake produces a vacuum of sorts during the growing season: warm air over the lake rises, sucking colder air off the land and creating offshore breezes. Cold air cannot settle over the vineyards and a constant flow of warmer air makes the growing season here longer than in other parts of the state. The escarpment's glacial soils are made up of gravel, sand, and clay over limestone bedrock. An [[aquifer]] provides mineral-rich ground water to the vines, encouraging deep root growth.<ref>{{cite web|url=http://www.wine-searcher.com/regions-wisconsin+ledge |title=Wisconsin Ledge wine region |publisher=Wine-searcher.com |date=2014-06-16 |access-date=2016-05-07}}</ref><ref>{{cite web|url=http://midwestwinepress.com/2011/10/30/wisconsin-ledge-ava-set-for-ttb-approval/|title=Wisconsin Ledge AVA Set for TTB Approval|work=midwestwinepress.com|date=18 October 2011 }}</ref>

==World Biosphere Reserve==
{{Main|Niagara Escarpment Biosphere Reserve}}
{{See also|List of UNESCO Biosphere Reserves in Canada}}

In February 1990, the Niagara Escarpment was a designated World [[Biosphere Reserve]] by [[United Nations Educational, Scientific and Cultural Organization|UNESCO]], making it one of 12 in Canada. Development and land use on and adjacent to the escarpment is regulated by the [[Niagara Escarpment Commission]], an agency of the Ontario government.<ref>{{cite web|title= Biosphere Reserve Information – Canada – Niagara Escarpment Biosphere Reserve|url= http://www.unesco.org/mabdb/br/brdir/directory/biores.asp?mode=all&code=CAN+06 |work= MAB Biosphere Reserves Directory|publisher= [[UNESCO]]|access-date= 2009-05-03}}</ref>

Cliffs along the scarp face have the oldest forest ecosystem in eastern North America.<ref>{{cite book |last=Kelly |first=Peter |date=2007-05-31 |title=The Last Stand: A Journey Through the Ancient Cliff-Face Forest of the Niagara Escarpment |publisher=Natural Heritage |edition=1st |isbn=978-1-897045-19-0 |url=https://www.amazon.ca/gp/product/1897045190/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&camp=15121&creative=330641&creativeASIN=1897045190&linkCode=as2 |access-date= 2018-04-04}}</ref> The oldest tree in Ontario is an eastern white cedar from 688 C.E.<ref>{{cite web |title=Ontario's oldest tree |author=Ancient Forest Exploration and Research |work=Ancient Forest Exploration & Research |url=http://www.ancientforest.org/ontarios-oldest-trees/ |access-date=2021-01-25 |archive-date=2017-12-28 |archive-url=https://web.archive.org/web/20171228112210/http://www.ancientforest.org/ontarios-oldest-trees/ |url-status=dead }}</ref> The oldest known tree in Wisconsin, a 1,300 year-old eastern white cedar, was found in Brown County.<ref>[https://www.wausaudailyherald.com/story/news/2019/04/22/oldest-tree-wisconsin-1300-year-old-red-cedar-niagara-escarpment-brown-county-greenleaf-doug-larson/3428841002/ The oldest known tree in Wisconsin is a 1,300-year-old cedar growing from a cliff]</ref>

==See also==
*[[Bayshore Blufflands]]
*[[Canadian Shield]]
*[[Cheltenham Badlands]]
*[[Greenbelt (Golden Horseshoe)|Ontario Greenbelt]]
*[[Golden Horseshoe]]
*[[List of escarpments]]
*[[Hamilton Mountain]]

==References==
{{Reflist}}

==External links==
{{Commons category|Niagara Escarpment}}
* [http://www.escarpmentnetwork.org/ Niagara Escarpment Resource Network] {{Webarchive|url=https://web.archive.org/web/20090813172338/http://www.escarpmentnetwork.org/ |date=2009-08-13 }}
* [http://www.niagaraescarpment.org/ Coalition on the Niagara Escarpment]
* [http://www.onmilwaukee.com/visitors/articles/niagaraescarpment.html The Niagara Escarpment: Wisconsin's eighth natural wonder]
* [https://archive.org/details/ReportNiagaraEscarpmentLegacyProjectMay2014 The Niagara Escarpment Legacy Project]

{{Ontario parks}}
{{Greatlakes}}
{{Niagara Falls}}{{Coord unknown|North American}}

[[Category:Niagara Escarpment| ]]
[[Category:Biosphere reserves of Canada]]
[[Category:Escarpments of Canada]]
[[Category:Escarpments of the United States]]
[[Category:Geological history of the Great Lakes]]
[[Category:Geology of the United States]]
[[Category:Golden Horseshoe]]
[[Category:Landforms of Niagara County, New York]]
[[Category:Landforms of Ontario]]
[[Category:Niagara Falls]]
[[Category:Stratigraphy of Ontario]]