Yankin Cascade

  

Yankin Cascade
General information
Gu mafi tsayi	Mount Rainier (en)
Height above mean sea level (en)	14,411 ft
Tsawo	1,100 km
Fadi	80 mi
Yawan fili	150,000 km²
Labarin ƙasa
Tsarin Daidaiton Labarin Kasa	46°51′02″N 121°45′36″W
Tsawon tsaunuka	Pacific Coast Ranges (en)
Kasa	Tarayyar Amurka da Kanada
Territory	Washington, British Columbia, Oregon da Kalifoniya
Geology
Period (en)	Pliocene (en)

Rawan Cascade ko Cascades babban tsaunuka ne na yammacin Arewacin Amurka, wanda ya tashi daga kudancin British Columbia zuwa Washington da Oregon zuwa Arewacin California. Ya haɗa da tsaunukan da ba su da aman wuta, kamar yawancin waɗanda ke cikin Cascades ta Arewa, da kuma fitattun tsaunuka da aka fi sani da High Cascades. Ƙananan ɓangaren kewayon a cikin British Columbia ana kiransa Cascades na Kanada ko, a cikin gida, azaman tsaunukan Cascade. Mafi tsayi a cikin kewayon shine Dutsen Rainier a Washington a

Cascades suna daga cikin Pacific Ocean's Ring of Fire, zobe na tsaunuka masu fitattun wuta da duwatsu masu alaƙa da ke kewaye da Tekun Pacific. Dukkanin fashewar da ke kusa da Amurka a cikin shekaru 200 da suka gabata sun fito ne daga Cascade Volcanoes. Biyu mafi kwanan nan sune Lassen Peak daga 1914 zuwa 1921 da kuma Babban fashewar Dutsen St. Helens a cikin 1980. Ƙananan fashewar Dutsen St. Helens sun faru tun daga, kwanan nan daga 2004 zuwa 2008. Yankin Cascade wani bangare ne na Cordillera na Amurka, kusan ci gaba da jerin tsaunuka (cordillera) waɗanda suka samar da yammacin "ƙashin baya" na Arewa, Tsakiya, da Kudancin Amurka.

Cascades gida ne ga wuraren shakatawa na kasa da yawa da wuraren kariya, gami da North Cascades National Park, Mount Rainier National Park, Crater Lake National Park, da Lassen Volcanic National Park. Rabin arewacin Pacific Crest Trail ya bi kewayon.

Yanayin ƙasa

Shahararrun tsaunuka masu fashewa a yankin Amurka na Cascades

Cascades sun miƙe zuwa arewa daga Lassen Peak (wanda kuma aka sani da Dutsen Lassen) a arewacin California zuwa haɗuwar kogin Nicola da Thompson a cikin British Columbia. Kogin Fraser ya raba Cascades daga tsaunukan gabar teku a Kanada, haka kuma kwarin Willamette daga babban yanki na Yankin Tekun Oregon. Mafi girman dutsen tsaunuka na Cascades, wanda aka fi sani da High Cascades, ya mamaye kewayen su, sau da yawa yana tsayawa ninki biyu na tsaunukan da ke kusa. Yawancin lokaci suna da tsayin gani (tsawo sama da layukan da ke kusa) na mil ɗaya ko fiye. Mafi girman kololuwa, kamar Dutsen Rainier mai tsawon ƙafa 14,411 (4,392 m), sun mamaye kewayen su tsawon mil 50 zuwa 100 (kilomita 80 zuwa 161).

Yankin arewacin kewayon, arewacin Dutsen Rainier, an san shi da Arewacin Cascades a Amurka amma ana kiransa da sunan Cascade Mountains a arewacin iyakar Kanada da Amurka, yana kaiwa arewacin iyaka na Cascades a Lytton Mountain . Gabaɗaya, Arewacin Cascades da Canadian Cascades suna da tsayi sosai; har ma da ƙananan tsaunuka suna da tsami kuma suna da glaciated, kuma kwari suna da ƙasa sosai dangane da tsaunuka da tuddai, don haka akwai babban taimako na gida. Yankin kudancin Cascades na Kanada, musamman Skagit Range, yana da kama da Arewacin Cascades, yayin da sassan arewa da arewa maso gabas ba su da ƙanƙara kuma sun fi kama da tsaunuka, suna kama da yankunan da ke kusa da Thompson Plateau.

Yankin yana kusa da Tekun Fasifik kuma a cikin iskar yamma da ke mamaye yankin, don haka yana samun ruwa mai yawa da dusar ƙanƙara, musamman a kan gangaren yamma saboda ɗagawa na orographic, tare da tarin dusar ƙanƙara na shekara-shekara har zuwa inci 1,000 (2,500 cm) (= 83 ƙafa (25 m)) a wasu yankuna. Dutsen Baker a Washington ya yi rikodin rikodin dusar ƙanƙara na ƙasa a cikin lokacin hunturu na 1998-99 tare da inci 1,140 (2,900 cm) (= ƙafa 95 (29 m)). Kafin wannan shekarar, Dutsen Rainier ya riƙe rikodin Amurka game da tarin dusar ƙanƙara a Aljanna a cikin 1978. Ba sabon abu ba ne wasu wurare a cikin Cascades su sami sama da inci 500 (cm 1,300) na tarin dusar ƙanƙara kowace shekara, kamar a tafkin Helen, kusa da Lassen Peak. Yawancin Manyan Cascades saboda haka fari ne tare da dusar ƙanƙara da ƙanƙara duk shekara. Gandun daji na yamma an rufe su da Douglas-fir (Pseudotsuga menziesii), hemlock na yamma (Tsuga heterophylla) da ja alder (Alnus rubra), yayin da gangaren gabas mai bushewa ya ƙunshi mafi yawan ponderosa pine (Pinus ponderosa), tare da wasu larch na yamma (Larix occimlockgalisia) da dutsen pine (Tsuga) (Abies lasiocarpa) da kuma subalpine larch (Larix lyallii) a wurare mafi girma. Ruwan sama na shekara yana ƙasa da inci 9 (230 mm) akan tsaunin gabas saboda tasirin inuwar ruwan sama..

Columbia Gorge alama ce inda Kogin Columbia ya raba Cascade Range tsakanin jihohin Washington da Oregon.

Bayan tuddai na gabas akwai wani tsaunin da ya fi bushewa wanda aka kafa shi shekaru miliyan 17 zuwa 14 da suka gabata ta hanyar kwararar Kogin Columbia Basalt Group. Tare, waɗannan jerin dutsen dutse mai fitattun wuta sun samar da murabba'in kilomita ,000 (520,000 ) Columbia Plateau a gabashin Washington, Oregon, da sassa na yammacin Idaho. 

Kogin Kogin Columbia shine kawai babban hutu na kewayon a cikin Amurka. Lokacin da Cascades ya fara haɓaka shekaru miliyan 7 da suka gabata a cikin marigayi Miocene, Kogin Columbia ya zubar da ɗan ƙaramin Plateau na Columbia. Yayin da kewayon ke girma, zaizayar kogin Columbia ya sami damar ci gaba da tafiya, yana zana kwazazzabo da babbar hanyar wucewa da aka gani a yau. Haka kuma kwazazzabin yana fallasa ɗora-ɓoye na basalt daga tudu. 

Tarihi

Kafin binciken Turai, kabilun Al'ummai na farko sun ba da suna da tsaunuka da yawa, gami da "Seekseekqua" don Dutsen Jefferson (Oregon) , "M'laiksini Yaina" don Dutsen McLoughlin, "Tahoma", sunan Lushootseed don Dutsen Rainier, da "Louwala-Clough", ma'ana "dutse mai shan sigari" don Dutse St. Helens.

A farkon 1792, mashigin jirgin Burtaniya George Vancouver ya bincika Puget Sound kuma ya ba da sunayen Ingilishi ga manyan tsaunukan da ya gani. An ba wa Dutsen Baker suna don Laftanar na uku na Vancouver, Joseph Baker, kodayake Bature na farko da ya gan shi Manuel Quimper ne, wanda ya sa masa suna la gran montaña del Carmelo ("Babban Dutsen Karmel") a cikin 1790.[19] Sunan Dutsen Rainier bayan Admiral Peter Rainier. Daga baya a cikin 1792, Vancouver ya sa Laftanarsa William Robert Broughton ya bincika ƙananan Kogin Columbia. Ya sanyawa Dutsen Hood sunan Ubangiji Samuel Hood, babban hafsan Sojan Ruwa na Sarauta. Dutsen St. Helens ya ga Vancouver a watan Mayu 1792, daga kusa da bakin kogin Columbia. An ba shi suna don Alleyne FitzHerbert, 1st Baron St Helens, jami'in diflomasiyyar Burtaniya.[1] Tafiyar Vancouver bai yi ba, duk da haka, ya ambaci kewayon tsaunin da ke ɗauke da waɗannan kololuwa. Ya kira shi kawai a matsayin "gabashin dusar ƙanƙara". Tun da farko masu binciken Mutanen Espanya sun kira ta Saliyo Nevada, ma'ana "dutse mai dusar ƙanƙara".

Bayyanar gefen yammacin Dutsen Shuksan a lokacin rani kamar yadda aka gani daga Artist Point a Washington

A cikin 1805, Lewis da Clark Expedition sun wuce ta hanyar Cascades a kan Kogin Columbia, wanda shekaru da yawa shine kawai hanyar da za a iya wucewa wannan ɓangaren kewayon. Su ne mutanen farko da ba 'yan asalin ƙasar ba da suka ga Dutsen Adams, amma sun yi tunanin Dutsen St. Helens ne. Lokacin da daga baya suka ga Dutsen St. Helens sun yi tunanin Dutsen Rainier ne. A kan tafiyarsu ta dawowa, Lewis da Clark sun hango wani tsawo amma mai nisa mai dusar ƙanƙara wanda suka ba da suna ga mai tallafawa balaguron, Shugaban Amurka Thomas Jefferson . Lewis da Clark sun kira Cascade Range "Dutse na Yamma".

Binciken Lewis da Clark, da kuma mazauna da 'yan kasuwa da yawa da suka biyo baya, sun haɗu da cikas ta ƙarshe ga tafiyarsu a Cascades Rapids a cikin Kogin Columbia, fasalin da ke kan kogin yanzu ya nutse a ƙarƙashin tafkin Bonneville. Ba da daɗewa ba, manyan duwatsun da ke sama da rapids an kira su "dutse ta hanyar cascades" kuma daga baya kawai a matsayin "Cascades". Amfani da farko da aka tabbatar da sunan "Cascade Range" yana cikin rubuce-rubucen masanin tsire-tsire David Douglas a cikin 1825.

Dutsen Hood shine mafi tsawo a jihar Oregon ta Amurka.

A cikin 1814, Alexander Ross, ɗan kasuwa na fata tare da Kamfanin Arewa maso Yamma, yana neman hanya mai yiwuwa a fadin duwatsu, ya bincika kuma ya haye arewacin Cascades tsakanin Fort Okanogan da Puget Sound. Rahoton tafiyarsa ba shi da tabbas game da hanyar da aka dauka. Ya bi ƙananan Kogin Methow zuwa cikin duwatsu. Wataƙila ya yi amfani da Cascade Pass don isa Kogin Skagit. Ross shine Turai-Amurka na farko da ya binciki yankin Kogin Methow kuma mai yiwuwa shine na farko da zai binciki Kogin Stehekin da yankin Bridge Creek. Saboda wahalar tsallaka arewacin Cascades da ƙarancin beaver, kamfanonin fata sun yi bincike kaɗan a cikin duwatsu a arewacin Kogin Columbia bayan Ross.

Binciko da daidaita yankin Cascades ta Turawa da Amurkawa ya sami haɓaka ta hanyar kafa babban wurin kasuwanci na Hudson's Bay Company (HBC) a Fort Vancouver kusa da Portland, Oregon na yau. Daga wannan tushe HBC ƙungiyoyin tarko sun yi tafiya a cikin Cascades don neman beaver da sauran dabbobi masu ɗaukar gashi. Misali, ta yin amfani da abin da aka fi sani da Siskiyou Trail, Hudson's Bay Company trappers su ne farkon wadanda ba 'yan asalin ba don gano kudancin Cascades a cikin 1820s da 1830s, kafa hanyoyin da suka wuce kusa da Crater Lake, Dutsen McLoughlin, Dutsen Dutsen Medicine, Dutsen Shasta, da Lassen Peak..

Kogin Coquihalla a cikin Cascades na Kanada

Hanyar tarihin siyasa a cikin Pacific Northwest ya ga kashin baya na Cascade Range da ake ba da shawara a matsayin iyakar iyaka a lokacin rikicin Oregon na 1846. Amurka ta yi watsi da shawarar kuma ta dage a kan 49th parallel arewa, wanda ya yanke iyakar arewacin Dutsen Baker. A cikin tsawon lokacin jayayya har zuwa ƙirƙirar Crown Colony na British Columbia a 1858, hanyar Hudson's Bay Company ta York Factory Express, da kuma hanyar brigades fur, sun bi kogin Okanogan tare da gefen gabas na Cascades da Kogin Columbia ta cikin kewayo. Ba a san hanyoyin wucewa ba kuma ba a yi amfani da su sosai ba. An yi amfani da Naches Pass don tukin shanu da dawakai zuwa Fort Nisqually. Kamfanin Hudson's Bay kuma ya yi amfani da Yakima Pass.

Amincewar Amurkawa na gefen Tekun Tekun bai faru ba sai farkon shekarun 1840, da farko kadan kadan. Bayan yerjejeniyar Oregon yunƙurin ƙaura daga Titin Oregon ya ƙaru kuma aka binciko hanyoyin wucewa da kwaruruka na abin da ke a halin yanzu jihar Washington kuma an cika su, kuma ba a daɗe da bin hanyar jirgin ƙasa ba. Duk da cewa manyan tituna da layin dogo da yawa ke bi da shi, kuma ƙananan ɓangarorinsa suna fuskantar babban shinge a cikin 'yan shekarun nan, manyan sassan kewayon suna da ƙarfi kuma suna hana jejin tsaunuka. Yawancin rabin arewacin Cascades, daga Rainier arewa, an kiyaye su ta wurin wuraren shakatawa na lardunan Amurka ko British Columbia (kamar EC Manning Provincial Park), ko wasu nau'ikan yanki mai kariya..

Lassen Peak a cikin California Cascades . Dutsen dutse mafi zurfi a cikin Cascade Range da kuma wani ɓangare na Lassen Volcanic National ParkGidan shakatawa na Lassen Volcanic

Yankin Kanada na kewayon yana da tarihin da ya haɗa da Fraser Canyon Gold Rush na 1858-60 da sanannen Cariboo Road, da kuma tsohuwar Hudson's Bay Company Brigade Trail daga Canyon zuwa ciki, Dewdney Trail, da tsofaffin hanyoyin da suka haɗa gabas zuwa kwarin Similkameen da Okanagan.

Babban layin kudu na layin dogo na Kanada Pacific ya ratsa kewayo ta mashigin kogin Coquihalla, tare da daya daga cikin tudu da dusar ƙanƙara a duk yankin Pacific Cordillera. Kusa da Hope, BC, titin jirgin ƙasa da Othello Tunnels, yanzu an daina aiki, shahararrun wuraren shakatawa na yawon buɗe ido don yin tafiye-tafiye da keke. Hanyar Coquihalla tana amfani da hanyar wucewa, wani megaproject na gwamnati wanda aka gina a matsayin wani ɓangare na haɓakar kashe kuɗi na Expo 86 na shekarun 1980, wanda yanzu shine babbar hanyar daga Tekun zuwa cikin Burtaniya ta Columbia. Traffic a da ya bi ta Fraser Canyon, zuwa yamma, ko ta Allison Pass da Manning Park tare da Babbar Hanya 3 zuwa kudu, kusa da kan iyaka.

Rushewar Dutsen St. Helens a shekarar 1980

Hanyar Barlow ita ce farkon kafa hanyar ƙasa ga mazauna Amurka ta hanyar Cascade Range a cikin 1845, kuma ta kafa hanyar haɗin kan ƙasa ta ƙarshe don Titin Oregon (a da, mazauna dole ne su rushe mayaudaran rafi na Kogin Columbia). Hanyar ta bar Columbia a abin da ake kira Hood River kuma ta wuce gefen kudu na Dutsen Hood a abin da ke yanzu Camp Camp, yana ƙarewa a Birnin Oregon. Akwai wurin fassara a can yanzu a "Ƙarshen Hanyar Oregon". An gina hanyar a matsayin hanyar biyan kuɗi - $5 kowace keken keke - kuma ta yi nasara sosai. 

Bugu da kari, an halicci Applegate Trail don ba da damar mazauna su guji rafting zuwa Kogin Columbia. Hanyar ta yi amfani da Hanyar California Trail zuwa arewa maso tsakiyar Nevada. Daga can, hanyar ta tafi arewa maso yamma zuwa arewacin California, kuma ta ci gaba da arewa maso yammacin zuwa Ashland na yau, Oregon. Daga can, mazauna za su tafi arewa tare da hanyar Siskiyou Trail zuwa cikin Kwarin Willamette.

Ban da fashewar 1915 na Lassen Peak mai nisa a Arewacin California, kewayon ya yi shuru sama da karni guda. Sannan, a ranar 18 ga Mayu, 1980, fashewar tsaunin St. Helens mai ban mamaki ya wargaza shiru kuma ya jawo hankalin duniya ga kewayo. Masana ilimin kasa kuma sun damu da cewa fashewar St. Helens alama ce da ke nuna cewa tsaunukan Cascade na dadewa na iya sake yin aiki sau ɗaya, kamar yadda a cikin lokacin daga 1800 zuwa 1857 lokacin da jimillar mutane takwas suka fashe. Babu wanda ya fashe tun daga St. Helens, amma duk da haka ana yin taka tsantsan, kamar Cascades Volcano Observatory da Dutsen Rainier Volcano Lahar Gargaɗi a cikin gundumar Pierce, Washington. 

Ilimin ƙasa

Geology na tectonics mai alaƙa da Cascade Range.

Yankin Cascade ya ƙunshi ƙungiyar dubban ƙananan tsaunuka masu fitattun wuta waɗanda suka gina dandalin dutsen dutse da tarkace. Hawan sama da wannan dandalin dutsen wuta akwai wasu manyan tsaunuka masu fitattun wuta, kamar Dutsen Hood da Dutsen St. Helens, waɗanda suka mamaye wuri mai faɗi.

Dutsen dutsen na Cascade ya bayyana sashin Arewa maso Yamma na Pacific na Zoben Wuta, jerin tsaunuka masu tsaunuka waɗanda ke gefen Tekun Pacific. Hakanan an san Zoben Wuta da girgizar ƙasa akai-akai. Dutsen aman wuta da girgizar asa suna tasowa ne daga tushen gama gari, wato subduction. A wannan yanayin, babban Plate na Juan de Fuca yana nutsewa ƙarƙashin Plate ta Arewacin Amurka a yankin Cascadia.[1] Yayin da tudun teku ke nutsewa cikin cikin duniyar da ke ƙarƙashin farantin nahiyoyi, yanayin zafi da matsa lamba suna ba da damar kwayoyin ruwa da ke kulle a cikin ma'adanai na dutsen dutse su tsere. Ruwan ya tashi zuwa cikin rigar da ke sama da farantin da ke ƙasa, ya sa wasu daga cikin rigar ta narke. Wannan sabuwar magma da aka kafa ta taso zuwa saman duniya don ta barke, ta samar da jerin tuddai (Cascade Volcanic Arc) a sama da yankin da aka rushe..

Amfani da Mutum

Yanayin ƙasa don aikin noma gabaɗaya yana da kyau, musamman ƙarancin wutar lantarki. Wannan ya fi yawa saboda duwatsu masu aman wuta galibi suna da wadata a cikin ma'adanai masu ɗauke da potassium kamar orthoclase, kuma suna lalacewa cikin sauƙi. Barazanar aman wuta, musamman lahar, su ma suna taimakawa wajen yada abubuwa masu aman wuta mai aman wuta, haka kuma tanadin ruwa a matsayin dusar ƙanƙara da ƙanƙara yana da mahimmanci ga aikin noma. Ana amfani da tsaunukan da dusar ƙanƙara ta rufe, irin su Mt. Hood da tsaunin Bachelor, a matsayin wuraren shakatawa a ƙarshen lokacin sanyi, yayin da lokacin rani suka zama sanannen tafiye-tafiye da hawan dutse. Yawancin ruwan narkewar su daga ƙarshe yana kwarara zuwa tafki, inda ake amfani da shi don nishaɗi, yayin da ake kama ƙarfin ƙarfinsa don samar da wutar lantarki kafin a yi amfani da ruwan don ban ruwa.

Saboda yawan magudanan ruwa masu ƙarfi, da yawa daga cikin manyan kogunan Cascades masu ratsawa zuwa yamma an lalata su don samar da wutar lantarki. Ɗaya daga cikin waɗannan, Ross Dam akan Kogin Skagit, yana riƙe da tafki wanda ya ratsa kan iyaka kudu maso gabashin Hope, British Columbia, mai nisan mil 2 (kilomita 3.2) zuwa Kanada. A gindin kudu maso gabas na Dutsen Baker, a Concrete, Washington, Kogin Baker yana damm don samar da Lake Shannon da Baker Lake.

Cascades suna da damar da ba a iya amfani da ita ba don ikon geothermal. Shirin Binciken Geothermal na Amurka yana binciken wannan yiwuwar. Wasu daga cikin wannan makamashi an riga an yi amfani da su a wurare kamar Klamath Falls, Oregon, inda ake amfani da tururi na dutse don dumama gine-ginen jama'a. Mafi girman zafin jiki na karkashin kasa da aka samu a cikin kewayon shine 510 °F (266 °C) ° F (266 ° C) a 3,075 feet (937 m) a ƙasa da bene na Newberry Volcano.

Muhalli

Oval-leaf blueberry a Dutsen Pilchuck

dazuzzuka na manyan itatuwa masu laushi (ja cedar na yamma, Douglas-firs, hemlocks na yamma, firs, pine, spruces, da sauransu) sun mamaye mafi yawan Cascade Range. Lokacin sanyi, hunturu mai laushi da zafi, lokacin rani mai bushe (yawanci sakamakon tasirin teku) suna son nau'ikan halittu masu tsayi, yayin da yanayin zafi mai sauƙi da ƙasa mai wadata ke inganta ci gaba mai sauri da tsawo.

Goat na dutse a kan Wallaby Peak a Arewacin Cascades

Yayin da matafiyi ke wucewa ta cikin Range na Cascade, yanayin ya fara yin sanyi, sannan kuma ya yi zafi da bushewa a gabas da santsi.[1] Yawancin tsaunukan Cascades na ƙasa da na tsakiya an rufe su a cikin gandun daji na coniferous; Tsawon tsaunuka masu tsayi suna da ciyayi masu yawa da kuma tudun tundra da glaciers. Yankin kudancin Cascades yana cikin lardin California Floristic, yanki mai yawan ɗimbin halittu.

fir" Itacen fir na Azurfa ya fi girma sama da 2500 ft, yayin da akwai moors, ciyayi, da tsaunin tsaunuka/ fir na fir daga 4500 zuwa 6000 ft a gefen yamma.  Tsayin bishiyar yana a ~ 6000 ƙafa.  A gefen gabas, dazuzzukan dazuzzukan dazuzzukan larch sun kai matsayi zuwa pine da dazuzzukan fir da ke ƙasa da 4200 ft, waɗanda ke zuwa ponderosa ƙasa da 2500 ft, wanda hakan ya kai maki zuwa ɓangarorin jeji kusa da matakin teku.  Sama da ƙafa 7500, filin ba kowa ba ne ba tare da ko dai babu tsire-tsire ko gansakuka da lichen kawai.     

Black bears, coyotes, Bobcats, Cougars, beavers, deer, elk, Moose, goats na dutse da wasu kungiyoyin wolf da ke dawowa daga Kanada suna zaune a cikin Cascades. Kasa da bears 50 suna zaune a cikin Cascades na Kanada da Washington.