Isikhathi se-Silurian

Esikhathini sePaleozoic sithola isikhathi esichazwe ngokusebenza okukhulu kwe-geological futhi okutholakala phakathi kwe-Ordovician ne I-Devonian. Kumayelana nesikhathi I-Silurian. Ngalesi sikhathi lapho kunomsebenzi ophakeme wokwakheka komhlaba, singathola ubufakazi besayensi ngokwakhiwa kwezintaba ezinkulu zezintaba kanye ne-supercontinent entsha eyaziwa nge-Euramérica.

Kulesi sihloko sizokutshela zonke izici, i-geology, isimo sezulu, izimbali nezilwane zenkathi yeSilurian.

Izici eziyinhloko

Isikhathi se-Silurian sithathe cishe iminyaka eyizigidi ezingama-25, kusukela eminyakeni eyizigidi ezingama-444 edlule kuya eminyakeni eyizigidi ezingama-419 edlule. Ngalesi sikhathi, kuyinto ejwayelekile ukuthi ibe semanzini angajulile ebusweni bamazwekazi ngoba ulwandle lwaluphakeme impela. Kososayensi, isikhathi seSilurian sithakazelisa impela ngoba sasinezinguquko zombili ezingeni le-geological kanye nasezingeni lezinhlobonhlobo zezinto eziphilayo.

Izitshalo zikwazile ukunqoba imvelo yasemhlabeni kwavela izinhlobo ezintsha ze-arthropods, amakhorali nezinhlanzi. Ezingeni lokwakheka komhlaba, futhi kungenzeka ukubona ukwakheka kwezinhlelo zezintaba ezahlukahlukene esizaziyo namuhla, njenge Izintaba ze-Appalachian futhi anemvelaphi yawo enkathini yamaSiluriya.

Isikhathi se-Silurian geology

Ngalesi sikhathi izwekazi elikhulu elibizwa ngeGondwana laliseningizimu yeplanethi. Zonke ezinye izwekazi ezaziwa kakhulu ngokuthi yiLaurentia, iBaltic neSiberia zazisesikhundleni esenyakatho. Izinga lolwandle lalikhuphuke kakhulu ngenxa yokuncibilika kweqhwa kusukela ekuqhephuzeni kwasekupheleni kwesikhathi esedlule. Lokhu kuphakama kolwandle Kubangele ukuthi okuthiwa ulwandle lwe-epicontinental lwakhiwe ngaphezulu kwama-supercontinents. Lezi bekumizimba yamanzi emincane, engajulile enwelela kuwo wonke la mazwekazi.

Umphumela we Ukukhukhuleka kwezwekazi yaqhubeka nokushintsha amazwekazi. Yile ndlela ezahlangana ngayo izifundazwe ezinkulu ezibizwa ngeLaurentia, iBaltica ne-Avalonia ukwakha i-supercontinent enkulu kakhulu egama layo lingu-Euramérica. Le nqubo yokwakheka komhlaba ibalulekile ekuqondeni umlando woMhlaba kanye nokuziphendukela kwemvelo kwawo ngesikhathi sePaleozoic.

Lesi sikhathi sabonakala ngokuvela kwezindawo ezinkulu zomhlaba. Izilwandle ezazikhona ngalesi sikhathi kwakunguPanthalassa, uPaleo Tethys, uRheico, uLapetus nolwandle lwase-Ural.

Isimo sezulu sesikhathi se-Silurian

Sonke lesi sikhathi, isimo sezulu seplanethi sazinza. Kwakungasekho zinguquko eziningi kangaka zesimo sezulu ezingeni lomhlaba jikelele. Ngokuyinhloko iSilurian yagqama ngokuba yisikhathi nesimo sezulu esifudumele. Izinguzunga zeqhwa ezazakhe ngesikhathi se-Ordovician zazibheke ngaseningizimu yeplanethi futhi ukuncibilika kwazo okwalandela kwadala ukwanda kolwandle.

Yize bekuyisikhathi esifudumele ngokujwayelekile, kunamarekhodi ezimbiwa phansi akhombisa ukuthi kwakuyisikhathi esinezivunguvungu ezimbalwa. Ngemuva kwalokho, izinga lokushisa komhlaba wonke libonakala liqala ukwehla, kupholisa imvelo kancane. Lokhu kwehla kwezinga lokushisa akubanga yisikhathi seqhwa. Ekupheleni kweSilurian kanye nase-Devonian, isimo sezulu saba nomswakama ngokwengeziwe futhi sifudumele ngenani elikhulu lemvula.

Flora

Ngaphandle kokuthi ekugcineni kwe-Ordovician kwaba nomcimbi omkhulu wokuqothulwa, ngesikhathi sempilo kaSilurian yathuthukiswa ngempumelelo emvelweni yasolwandle, ikakhulukazi. Zonke izinhlobo ezikwazi ukusinda ekupheleni kwe-Ordovician zikwazile ukwehlukahluka zaze zaphendukela ezigabeni ezahlukahlukene.

Ake sihlaziye izitshalo kuqala. Ezindaweni zemvelo zasolwandle kwakunenani elikhulu lolwelwe, ikakhulukazi oluluhlaza, olwasiza ukukhiqiza ukulingana kwemvelo. Lokhu kungenxa yokuthi bayingxenye yamaketanga okudla ayethuthuka. Ngalesi sikhathi cIzitshalo ze-Vascular zaqala ukukhula, ezinemikhumbi yokuqhuba eyi-xylem ne-phloem.

Ekuqaleni kwalesi sikhathi isimo sezwe sasihluke kakhulu kunesolwandle. Ezindaweni zasolwandle, ukuphila kwathuthuka futhi kwahlukahluka kakhulu. Ngokuphambene, kuzo zonke izindawo ezihlala emhlabeni kwakubukeka kuyincithakalo futhi yomile. Kwakunezindawo ezimbalwa kuphela ezinamadwala, indawo enjengogwadule kanye nama-humus athile. Izitshalo ezamila emhlabeni kwakudingeka zihlale ziseduze nemithombo yamanzi. Ngale ndlela bakwazile ukuba nalezi zakhi nezakhi ezitholakalayo. Le ndlela yaba khona izitshalo zokuqala esizaziyo njengama-bryophytes.

Fauna

Ngokuqondene nezilwane, ekugcineni kwe-Ordovician kwakukhona inqubo yokuqothulwa okukhulu okwathinta kakhulu izilwane. Kodwa-ke, kuso sonke lesi sikhathi, amaqembu ezilwane ezinjenge-arthropods athuthuka. Kusukela kulesi sikhathi sebeluleme cishe izinsalela ezingama-425 ezimele abantu bakule phylum. Izinjabulo bezincipha esikhathini esedlule futhi zaqhubeka nokuba khona kuzinto eziphilayo zasolwandle. Kodwa-ke, endaweni, baphela.

Ngokufanayo, Ngesikhathi se-Silurian, ama-myriapods nama-chelicerates avela okokuqala.. Lawa maqembu ezilwane aqala ukugcwala izindawo zokuhlala zasemhlabeni. Iqembu lama-mollusk limelwe ngalesi sikhathi yizinhlobo zama-bivalves nama-gastropods. Babehlala ikakhulu olwandle.

Ama-crinoids, abonwa njengama-echinoderms amadala kakhulu emhlabeni njengoba nawo ayekhona ngalesi sikhathi. lezi zazine-peduncle eyayisiza ukuba ifakwe kwi-substrate. Baphela ekupheleni kweSilurian.

Emkhakheni wezinhlanzi sinokuhlukahlukana okukhulu. Esikhathini esedlule ama-ostracoderms ayesevele evela. Lezi izinhlanzi ezingenamhlathi futhi zibhekwa njengezilwane ezinomgogodla ezindala kunazo zonke embhalweni wezinsalela. Ezinye izinhlobo zezinhlanzi zaqala ukuvela, phakathi kwazo ezazinemihlathi eyaziwa ngokuthi ama-placoderms zagqama. Esinye sezici ezimele zalesi silwane ukuthi Zine-cuirass ngaphambili komzimba. Abanye ochwepheshe baqinisekisa ukuthi ekupheleni kwalesi sikhathi kwavela izinhlanzi ezinesigaxa.

Imifula yamakhorali nayo ibaluleke kakhulu selokhu yavela ngalesi sikhathi. Kulapha lapho kwakhiwa khona izixhobo zamakhorali ezinkulu ngempela. Lokhu kungenxa ye- izinhlobo zamakhorali ezikhona zingahlukaniswa ngokuzama ukubonga ngemisebe eguqukayo.