Tor (tsarin dutse)

Tor (tsarin dutse)
Bayanai
Ƙaramin ɓangare na	rock formation (en) , Rashin da aka yi da tudu

Wani abu a cikin Altai Krai, kudancin Siberia

Tor, wanda kuma Masana ilimin ƙasa suka sani da ko dai masallaci ko kopje, babban dutse ne mai zaman kansa wanda ke tashi ba zato ba tsammani daga gangaren da ke kewaye da shi mai santsi da taushi na taron tsaunuka ko tsaunuka. A tudun maso Yammacin Ingila, ana amfani da kalmar ne ga tuddai da kansu - musamman manyan wuraren Dartmoor a Devon da Bodmin Moor a Cornwall.

Magana

Kodayake sunayen wuraren Ingilishi galibi suna da ilimin Celtic, Oxford English Dictionary ba ya lissafa wani nau'i ga kalmar Tsohon Ingilishi a ko dai Breton ko yarukan Cornish (an yi tunanin cewa Gaelic na Scotland ya samo asali ne daga kalmar Tsohon Turanci). Saboda haka an yarda da cewa kalmar Ingilishi Tor ta samo asali ne daga kalmar Tsohon Welsh, ma'ana tarin ko tarin.

Kafawa

Kit-Mikayi, sanannen taur a kusa da Kisumu, Kenya

Tors sune siffofin ƙasa waɗanda aka kirkira ta hanyar rushewa da yanayin dutse; galibi granites, amma kuma schists, dacites, Dolerites, ignimbrites, sandstones da sauransu. Tors galibi ƙasa da mita 5 (16 tsawo. An gabatar da ra'ayoyi da yawa don bayyana asalin su kuma wannan ya kasance batun tattaunawa tsakanin masana kimiyyar ƙasa da masana kimiyyyar ƙasa, da masu ilimin ƙasa. An yi la'akari da cewa an halicce tors ta hanyar Tsarin geomorphic wanda ya bambanta sosai a cikin nau'i da tsawon lokaci bisa ga bambance-bambance na yanki da na gida a cikin yanayi da nau'ikan dutse.

Misali, dutsen Dartmoor an sanya shi kusan shekaru miliyan 280 da suka gabata. Lokacin da duwatsun murfin suka lalace an fallasa su ga tsarin sinadarai da na jiki. Inda haɗin gwiwa ke kusa, manyan lu'ulu'u a cikin dutse suna rushewa cikin sauƙi don samar da yashi mai yashi wanda aka sani a cikin gida kamar growan. Ana cire wannan cikin sauƙi ta hanyar solifluction ko wankewa na ƙasa lokacin da ba a kare shi da ciyayi ba, musamman a lokacin dogon sanyi a lokacin zamanin Quaternary ice - periglaciation.

Tor kusa da taron kolin Knocknagun, a Wicklow, Ireland

Inda haɗin gwiwa ya faru da nisa sosai, manyan tubalan zasu iya tsira kuma su kasance sama da yanayin yanayi, suna tasowa cikin tors. Wadannan na iya zama monolithic, kamar a Haytor da Blackingstone Rock, amma galibi ana rarraba su cikin ɗakunan, galibi ana shirya su a cikin hanyoyi. Kowane tarin na iya haɗawa da matakai da yawa ko matakai, wanda zai iya zama ya rabu: matakai masu girgiza ana kiransu duwatsu. Wadannan tarin suna da rauni ga aikin sanyi kuma sau da yawa suna rushewa suna barin hanyoyin tubalan da ke ƙasa da gangaren da ake kira clitter ko clatter. Har ila yau, yanayin yanayi ya haifar da "basins na dutse" wanda aka kafa ta hanyar tara ruwa da maimaita daskarewa da narkewa. Ana samun misali a Kes Tor a kan Dartmoor .

Dating na 28 tors a kan Dartmoor ya nuna cewa mafi yawansu matasa ne masu ban mamaki, kasa da shekaru 100,000 na bayyanar farfajiyar, ba tare da wani sama da shekaru 200,000 ba. Wataƙila sun fito ne a farkon babban zamanin kankara na ƙarshe (Devensian). Sabanin haka Cairngorms na Scotland, wanda shine sauran tarin dutse na dutse a Burtaniya, tsofaffin tors da aka rubuta suna tsakanin shekaru dubu 200 da 675 na fallasawa, har ma da waɗanda aka canza su da glacially suna da kwanakin shekaru 100-150,000.