North America: da taimako da kuma ta siffofin

Ƙasa ma'adanai North America - duk karatu a makaranta yau a labarin kasa darussa. Ilimi daga cikin wadannan al'amurra ne dole ba kawai ga jarrabawa, amma kuma ga sauran ci gaba. Bayan duk, tilas kowanne daga cikinmu ya gane cewa shi ne da surface na duniya a kan da muke rayuwa.

North America, cikin sauƙi na wanda za mu tattauna a wannan talifin yayi kama da irin na tsaye dissection South America. Iko bel na Cordillera duwãtsu lullube tare gabar yammacin zuwa 7000 km. Advantageously, da lebur ne m rabin na ɓangaren duniya. Duk wannan ya nuna cewa da taimako na nahiyar Amirka yana da karfi da dangantaka. Duk da haka, akwai gagarumin bambanci tsakanin wadannan nahiyoyi. A musamman, kamar yadda Cordillera dutsen tsarin ne yawa fadi da kuma hadadden tsarin fiye da Andes (wanda kuma ake kira Andean Cordillera). Sun kunshi dukan tsarin jeri, daban-daban tectonic da ma'aunan kasa tsarin ne bambanta.

m zone

A bayyane yake bambanta kusan duk kan Cordillera 5 orotektonicheskih tsaye zones. A farko daga cikin wadannan, da m - Laramide orogeny ridges: Mount MacKenzie, Brooks Range, Ridge Eastern Sierra Madre, Rocky Mountains. A karshen za a iya raba bisa ga peculiarities na orography kashi biyu: kudu da arewa. Tsakanin su tsaye a kasashen waje Yellowstone Plateau. Madaidaici straightness siffofin ne mai haske orographic fasali.

Front Range na Rocky Mountains

Front Range na Rocky Mountains (North America) yana da wadannan taimako: shi lullube kusan 2000 km a mike line, shafi na gaba, mutunci da kuma uniformity na ta ma'aunan kasa tsarin. Ridge fayyace, lashe m high kololuwa, da tsawo daga wanda ya kai 4000 m. Yana hankali sauka a gabas zuwa Great filayen. Front Range zuwa yamma ta tectonic laifi a arewacin. A tsakiyar dutsen rage. Suka haye kogin Pis, wanda shi ne daya daga cikin kafofin da MacKenzie River. Front Range a kudancin fadada. An raba takamaiman jeri, da tsawo daga wanda yake babba: Lewis, Caribou, Selkirk. A wannan bangare akwai mafi girma a kololuwa Front Range. Robson ne wani dutse (tadawa 3954 m), da na Dutsen Columbia (3747 m). Mai tsayi siffofin North America topography hali na Front Range. Ya kuma halin da mai karko da kuma gagarumin glaciation.

Rocky Mountains a kudancin

Single kunya Rockies ba nunawa a kudancin. Ga su an hada da mutum iri-iri, wani lokacin ware da kuma raba ta "Parks" - m tasa, wakiltar wani tudu-kamar sassan cewa haɗawa tare da manyan pool Great filayen. Sashe na daga cikin ridges (Sangre de Cristo, Wasatch) miƙa kusan daga arewa zuwa kudu. Sauran (msl, Uinta Mountains) - a yammacin-gabas shugabanci perpendicular zuwa gare su. Babba tsawo da nisa daga wannan dutse bel da aka cika da rashin ci gaba. A iyakar tsakanin Great sararan kasa da Rocky Mountains ne sosai a fili ya bayyana: da m bango - gangaren duwãtsu. Kudancin sashe - wadannan ne na hali epiplatform duwãtsu da aka kafa bayan da kunnawa da gefen daya daga cikin tsoho dandamali.

Belt ciki plateaus da plateaus

Next - bel ciki plateaus da plateaus kafa a nevadiyskuyu nadawa a kan babban yankin na Arewacin Amirka. A taimako ne halin da folded nevadiyskimi Tsarin wakilta peniplenami. A cikin wannan sashi, akwai wani tudu, wanda aka tsare a ", niƙaƙƙun gaɓãɓuwa" na zamanin d North American dandali da kuma clamped Cordillera (Northern Mass, Colorado Plateau). The most intermountain filayen Fraser, Yukon, Mai girma Basin, Colombia, Arewa kuma ta Tsakiya Mass, Colorado.

Great Basin

Great Basin - denudation tudu, da most a yankin. Wannan yanki, wanda fadin shi ne har zuwa 800 km, in general, shi ne wani canzawar lebur da dutsen saman da predominance na tsohon. A kan talakawan 1500m tashe Filato surface. Duk da haka, manyan hawa da sauka a cikin duwatsu. Filato layi daya ridges rarraba da Heights na game 3 km (Wheeler ganiya - 3982 m). Deep depressions, kira Bolson, karya tsakanin su. An Semi-kewaye da kewaye tasa, wanda shi ne wani yanki na ciki magudanun ruwa. Mutuwa Valley - daya daga cikinsu (-85 m).

Relict fi sukan samu (ciki har da Cones na volcanoes).

Colorado Plateau da kuma Grand Canyon

Colorado Plateau - shi ne daya daga cikin mafi musamman kusurwa duniya tamu, wanda aka sani ga North America. Its taimako ne da kyau sosai. A cewar ta ma'aunan kasa tsarin (kwance jirgin undisturbed dutsen sedimentary kankara shekaru daban-daban - daga zamanin d to verhnepaleoziyskih kwance a crystalline ginshiki) ne a Filato kama da North American dandali. Its surface - m bayyana, wanda ya kai wani tsawo na 3860 m.

Janye daga cikin tudu ne Grand Canyon (North America). Topography da kuma sauyin yanayi suna janyo hankalin zuwa wannan wuri da yawa yawon bude ido. Grand Canyon (hoton da ke ƙasa) da aka kafa daga Colorado River, a tsakiyar tafarkinsa. Yana kai zurfin 1800 m, wani nisa na 8 zuwa 25 km a kan tudu da kuma 1km a kasa matakin. M gangara ne ban sha'awa, m halayyar da Grand Canyon. Sun fito daga cikin aiwatar da erosive lalacewar da weathering. A crystalline tushe na saka Tuddan kunkuntar hanya.

Inner dutsen bel

The uku zone - ciki dutsen - bel nevadiyskih jeri: Coast Mountains, da Alaska Range, da Cascade Mountains, da Sierra Nevada, da kuma mai gangara Volcanic Sierra Madre Occidental. -Gaskiya bambanci tsakanin wadannan ridges. Igneous kankara fi yawa a cikin su tsari. Cascade Mountains - batholith da volcanic Cones, a rataye a kan shi. A kunya na Sierra Nevada shi ne wani asymmetric giant crystal batholith da gangaren m yammacin da kuma gabashin gangara.

bel synclinoria

A karo na hudu zone ne zone synclinoria. Wannan rage na zone, wanda aka kafa a cikin Neogene. Sashe na daga shi ne a halin yanzu wakilta daban-daban marine bays, straits. A ƙasar shi ne kwarin Mutuwa, Mai girma Tsakiya Valley, ƙananan kai na Kogin Colorado.

Far West zone

Sau biyar - matsananci yamma. Yana da wani bakin teku bel na folded mai tsayi ridges kamar yadda Aleut (akwai 25 aiki volcanoes), Kenai Larabawa, Island Ridge zuwa Victoria ganiya (tsawo - 2200 m), Chugachsky Ridge Larabawa Victoria, Coast jeri, Range Sierra Madre del Sur. Dukansu suna da matsakaici-high, amma mafi shahararren kololuwa sama 2 km.

Dangane da irin nisan da glaciation, mai tsanani daga orographic tsaye zones, tectonic da erosional dissection, da Cordillera ne zuwa kashi 4 morphostructural yankin: Cordillera na Mexico, da Amurka Cordillera Cordillera Cordillera na Canada da kuma Alaska.

A gabashin nahiyar

Abin da wani taimako zuwa ga North America a gabas? Bari mu fuskanci shi. Kamar yadda muka gani, samar da North American topography ne kullum lebur a gabashin nahiyar. M shi ne daukaka (Tsakiya, Laurentian) da kuma high filayen. Kwaruruka ne tare da bakinta: Primeksikanskaya, Atlantic yankin, Prigudzonskaya da Mississippi a cikin ƙananan kai na wannan kogi.

Appalachian dutsen bel

A North America, da bambanci ga ta Kudu, wani dutsen bel lullube tare gabas Coast - Appalachian. Wannan tsarin dutsen jeri, daga Gulf of St. zubar. Lawrence ya game 33-32 ⁰ s. m., cewa shi ne kusan 2,300 kilomita. Tsibirin na Newfoundland ne arewacin mahada. Appalachian - shi epiplatform high duwãtsu. A muhimmanci bambanci tsakanin kudanci da arewacin sassa na dutsen zangon sa tectonic halaye da kuma yanki tsarin. Graben Hudson ne iyaka tsakanin arewaci da kuma kudancin Appalachian. Northern Appalachians matsayin dukan - shi ne undulating tudu. Yana aka mamaye mutum dutsen jeri ko dutse jeri. Northern Appalachian zoba da Quaternary glaciation. Saboda haka, siffar duwatsu yanzu - lebur, kawai mafi girma kololuwa sun circuses tare da m katangu.

kudancin Appalachians

Canzawar dogon layi daya kwari da ridges na daban-daban Kudancin Appalachians. Daga gabas da yamma mika tare da kafa na kan tudu. Yana Piedmont a yamma - wani lebur bayyana daga denudation, wanda aka kafa ta Early Cambrian crystalline kankara. Daga shi yakan steeply zuwa yamma sarkar na dutsen jeri, kusan m (Kohut, Unakite, Black, da hayaki, babban, blue, da dai sauransu), Height - 1-1.5 km. Wannan "haihuwa dutse" - m tsakiya Caledonide, cikin shirye denudation.

Belt ridges da kwaruruka

Daya daga cikin mafi ƙwarai yankunan da Appalachian Mountains aka located yamma da su. Wannan ake kira Sun Mountain, ko bel na ridges da kwaruruka. Ga wasu ban sha'awa fasali na taimako daga Arewacin Amirka. Sedimentary kankara na Paleozoic zamanin da aka hada da dukan ƙasa: jeri - shales da sandstones kwarin - dolomites da limestones. Miƙa ga daruruwan kilomita zuwa kudu maso yammacin zuwa arewa-gabashin line stretch na duwatsu, m kwaruruka m da lebur-shugaba ko tsefe tare da kunkuntar ridges. A tsawon 500-600 mita, kasa na kwaruruka. ridges kololuwa isa 1-1.2 km. Valley tectonically wakiltar anticlinoria da ridges ne synclinoria. Wannan ne, a wannan lokaci ne a fili gani mismatch irin tectonic tsarin na zamani tsari, wanda yana da wani taimako a nan, a Arewacin Amirka. Photos of Appalachia da aka gabatar a kasa.

Wannan misali ne na wurare dabam dabam, ko inversion irin taimako. An samu a duwãtsu ne quite rare, kuma mafi haske a cikin Appalachians. Wannan irin taimako tare da Lines fara da za a kira "Appalachian taimako." Belt "matasa dutse" a yamma tarnhayar da Appalachian Filato (Cumberland, Allegheny). Yana da wani protrusion wanda tsayinsa ne 300-400 m. Wannan shi ne muhimmanci mafi girma Filato Piedmont. Its surface gabashin baki ya ta'allaka ne a wani tsawo na game 1.2 km, da yamma - 500 m Plateau wuraren warai dissected kwaruruka daban-daban na gudãna (kwazazzabo bottoms da kunkuntar da kuma m gangara) ..

To, a yanzu da cewa taimako na North America da aka takaice sake nazari a cikin wannan labarin, muna fata zai kasance da sauki a gare shi ya sa ya gabatar.