Niagara Escarpment

[[Image:Niagara-Escarpment-Rattlesnake.jpg|thumb|right|300px|Rattlesnake Point near [[Milton, Ontario]].]] [[Image:Niagara Escarpment at Wasaga Beach ON.jpg|thumb|right|Blue Mountains near [[Collingwood, Ontario]].]] [[Image:Niagara Escarpment map.png|thumb|right|Niagara Escarpment (in red)]] The '''Niagara Escarpment''' is a long [[escarpment]], or [[cuesta]], in the [[United States]] and [[Canada]] that runs westward from [[New York State]], through [[Ontario]], [[Michigan]], [[Wisconsin]] and [[Illinois]]. It is composed of the Lockport geological formation of [[Silurian]] age, and is similar to the [[Onondaga (geological formation)|Onondaga geological formation]], which runs parallel to it and just to the south, through [[western New York]] and [[southern Ontario]]. The escarpment is most famous as the cliff over which the [[Niagara River]] plunges at [[Niagara Falls]], for which it is named. The Niagara Escarpment is the most prominent of several escarpments formed in the bedrock of the [[Great Lakes Basin|Great Lakes basin]]. From its easternmost point near [[Watertown, New York]], the escarpment shapes in part the individual basins and landforms of Lakes [[Lake Ontario|Ontario]], [[Lake Huron|Huron]] and [[Lake Michigan|Michigan]]. In [[Rochester, New York]], there are three waterfalls over the escarpment where the [[Genesee River]] flows through the city. The escarpment thence runs westward to the Niagara River forming a deep gorge north of [[Niagara Falls]], which itself cascades over the escarpment. In [[southern Ontario]] it spans the [[Niagara Peninsula]], closely following the Lake Ontario shore through the cities of [[St. Catharines, Ontario|St. Catharines]], [[Hamilton, Ontario|Hamilton]] and [[Dundas, Ontario|Dundas]], 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 located 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 then extends southwards into Wisconsin following the [[Door Peninsula]] through the [[Bayshore Blufflands]] and then more inland from the western coast of [[Lake Michigan]] and [[Milwaukee]] ending northwest of [[Chicago, Illinois|Chicago]] near the Wisconsin-Illinois border. ==Formation== {{stack| [[Image:Niagara-Escarpment-Winter-IMG 0626.JPG|right|thumb|200px|Niagara Escarpment in Grimsby, Ontario from approx 3500 feet above sea level]] [[Image:HamiltonOntarioSkylineC.JPG|right|thumb|200px|Hamilton Skyline, view from atop the Niagara Escarpment]] [[Image:Bruce-Trail-bmountain.jpg|200px|thumb|right|200px|A section of escarpment cliff, seen from the Bruce Trail in Ontario.]] [[Image:NiagaraEscarpmentOutcroppings LakeMichiganShore.jpg|thumb|right|200px|[[Outcrop]]ping in [[Door County, Wisconsin]] approximately 10 feet (3 m) from [[Lake Michigan]].]] [[Image:NiagaraEscarpmentCalumetCounty.jpg|thumb|right|200px|Calumet County, Wisconsin]] }} Study of rock exposures and drillholes demonstrates that there is no displacement of the rock layers at the escarpment: this is not a [[Fault (geology)|fault line]] but the result of unequal [[erosion]]. The escarpment's [[caprock]] is dolomitic [[limestone]] ("[[dolostone]]"), which is more resistant and overlies weaker, more easily eroded shale as a [[weathering]]-resistant "cap". The escarpment thus formed over millions of years through a process of differential erosion of 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 conceal the Niagara Escarpment, such as north of [[Georgetown, Ontario]], where it actually continues under [[glacial till]] and reappears farther north. The dolostone cap was laid down as sediment on the floor of a marine environment. In Michigan, behind (i.e., southwest of) the escarpment, the ''cuesta'' capstone slopes gently to form a wide basin, the floor of an [[Ordovician]]-Silurian age tropical sea. (The escarpment essentially represents the remnant shoreline of that sea.) There the constant depositing of minute shells and fragments of biologically-generated [[calcium carbonate]], mixed with sediment washing 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 (dolomitic) sedimentary strata in the same fashion. Worldwide sea levels were at their all-time maximum in the Ordovician; as the sea retreated, erosion inevitably began. This dolostone basin contains Lakes Michigan, Huron and Erie. (The geological formations under Lakes Superior and Ontario were formed from volcanic rifts. Soft basalt line its canyon walls, bottoming at 1300 feet below sea level.) ==Human geography== The [[Welland Canal]] allows ships to traverse the Escarpment between [[Lake Erie]] and [[Lake Ontario]] on the Niagara Peninsula of Ontario. 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]]. 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, Ontario|Milton]]. Rock exposed on the face of the escarpment can be seen along [[Highway 26 (Ontario)]] from [[Owen Sound]] eastwards towards [[Meadford, Ontario]]. [[Hamilton, Ontario]], is situated on the escarpment in such a way that the North end of the city is below and the South part above. Affectionately referred to as "The Mountain" by its residents, there are a number of roads or "mountain accesses" that join the urban core below with the suburban expansion above. [[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. There are a number of different animal and geometric effigy mounds, and the remains of a turn-of-the-century limestone quarry and kiln within the park. The relief and exposed edge is used by windmill farms stretching from Pipe, Wisconsin to Brownsville, Wisconsin. Wind speeds average 18 mph along this stretch. Many resorts and [[ski country|ski areas]] in Ontario, Michigan, Wisconsin and New York are located along the Escarpment. == Vineyard land == On the Canadian side of the border the Niagara Escarpment is a group-sub-appellation comprising the [[Short Hills Bench]], The 20 Mile Bench and the Beamsville Bench. On the US side of the border is the [[American Viticultural Area]] of [[Niagara Escarpment AVA]]. ==World Biosphere Reserve== {{see also|List of UNESCO Biosphere Reserves in Canada}} In February 1990, the Niagara Escarpment was designated a 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. ==See also== * [[Greenbelt (Golden Horseshoe)|Ontario Greenbelt]] * [[Oak Ridges Moraine]] * [[Canadian Shield]] * [[Cheltenham Badlands]] * [[Onondaga Escarpment]] ==External links== {{Commons category|Niagara Escarpment}} *[http://www.escarpmentnetwork.org/ Niagara Escarpment Resource Network] *[http://www.niagaraescarpment.org/ Escarpment Coalition] *[http://www.lockport-ny.com/Museum/rocks.htm Lockport formation diagrams and rocks] {{Ontario parks}} {{Greatlakes}} {{Coord unknown|North American}}