Munguva Nguva yeCenozoic Pakave nekuchinja kwakasiyana-siyana pasirese zvese padanho regeology uye maruva nemhuka. Nhasi tichataura nezvenguva yechitatu yakaumba iyo Cenozoic. Zvayo ndezve Oligocene. Iyo Oligocene yakapararira kubva pamamiriyoni makumi matatu nematatu emakore apfuura kusvika pamamirioni makumi maviri nematatu apfuura. Mumakore ose aya nyika yedu yakave neshanduko dzinooneka. Shanduko idzi ndidzo dzakakonzera kugoverwa patsva kwezvinhu zvipenyu, zvese zvirimwa nemhuka. Uye zvakare, mamiriro ekunze akaita chinzvimbo chakakosha panguva yekuchinja kwezvinhu zvipenyu sezvo zvakagadzira mamwe mamiriro kuitira kuti dzimwe mhuka kana zvirimwa zvikwanise kubudirira zvakanyanya uye zvimwe zvirege kurarama. Nenzira iyi, fomu nyowani yesarudzo yakasikwa yakavambwa.
Muchikamu chino tiri kukuudza zvese zvaunoda kuti uzive nezve Oligocene.
Mhando huru
Iyo Oligocene inguva yakagara ichifadza vese nyanzvi dzinoisa pfungwa pakudzidza iyo nguva yegeological. Vose avo vakapedza nguva yakakwana kuti vadzidze zvakavanzika zvezvikamu zvakasiyana zve geological zvepasi vakasara nezvinhu zvinonakidza zvakaitika kupasi redu panguva yeOligocene.
Inguva yakatora avhareji yemamiriyoni gumi nerimwe emakore. Munguva ino makondinendi akagadzirwazve nekuda kwekufamba kwemahwendefa emakondinendi. Sangano iri rakonzera kuti makondinendi ave nezvinzvimbo zvakafanana neavo vanogara nhasi. Iyo Oligocene inozivikanwa zvakare seyezera rezvipuka. Uye iri iro iro iro boka remhuka dzinogona kusangana nekusiyana kukuru uye kusiana panguva ino. Iyo iri panguva ino yemamiriyoni gumi nerimwe emakore panogovaniswa zvidimbu zvezvipuka zvakaita semakonzo kana canid.
Nezve geology yeOligocene yakanga iri nguva yeakakura geological uye orogenic chiitiko. Tinogona kuona kuti kupatsanurwa kwepamusoro kondinendi Pangea kwakaramba kuchienderera uye zvizhinji zvezvimedu zvacho zvakatamiswa kuti zvitore chinzvimbo chakafanana nechavanacho nhasi. Maitiro maviri akakura orogenic akaitika panguva ino: iyo Laramide Orogeny uye Alpine Orogeny.
Oligocene Geology
Tichaenda kuburikidza nehunhu hwese hwaOligocene rimwe nerimwe. Tinotanga ne geology. Kupatsanurwa kwenyika yepamusoro kondinendi inozivikanwa sePangea zvakawedzera kuoneka pakapatsanurwa chidimbu chinoenderana neSouth America. Uku kushanduka kwekondinendi kwakakonzera kufamba kunonoka kuenda kumadokero kuitira kusangana neNorth America nekuumba zvatinoziva nhasi sekondinendi yeAmerica muhuwandu hwayo.
Antarctica yakaenderera mberi nekuparadzaniswa kwayo kubva kumamwe makondinendi uye chando chakavhara pakukwira kwachiri kuswedera pedyo neSouth Pole. Kune nyanzvi dzakawanda dzakaramba mhedzisiro dzakasiyana senge panguva ino ndiro inoenderana nekondinendi ye Africa yakabatana neEurasia uye yakazviitawo nechidimbu icho chatinoziva manje seIndia.
Pakupera kweOligocene, vese masasi epasi vaive vatove pachinzvimbo chakangofanana neicho chatinacho nhasi. Izvo zvinoenda kumakungwa. Makungwa akarongedzwa nenzira yekuti paive nemakungwa akati wandei akapatsanura makondinendi anhasi. Pakati pemakungwa aya tinogona kutaura nezvePacific Ocean, Atlantic Ocean neIndia.
Mamiriro ekunze Oligocene
Kana iri yemamiriro ekunze eOligocene, mamiriro acho anga akanyanyisa. Yakanga ichinyanyozivikanwa nekushisa kwakadzika kwazvo. Munguva iyi yese Antarctica neGreenland yakaramba yakafukidzwa nechando uye ichiwedzera nekuwedzera. Saizvozvowo, apo Antarctica yakaparadzaniswa zvachose kubva kuSouth America, zvakakonzera kuti masaisai akasiyana emumvura atenderere kumativi ese. Imwe yeaya mafungu egungwa iAntarctic Circumpolar. Iyi yemvura yegungwa inoonekwa seimwe yezvakanyanya kukosha, nekuti yaive nebasa rekufukidza kondinendi yese yeAntarctica nechando uye kuumbwa kwemazaya echando.
Kuderera kwetembiricha yepasirese kwakakonzera mhedzisiro mukushandurwa kwezvimwe zvipenyu. Iko kukura kwehuswa kwaive coniferous uye deciduous masango. Miti iyi yakakwanisa kurarama munzvimbo dzakanyanyisa idzi nekuti inokwanisa kurarama mukutonhora kwakadzika.
Flora nemhuka
Hupenyu hwese hwakave nekuwedzera nekusiyana-siyana kuva zvirimwa nemhuka. Kunyangwe hazvo mamiriro ekunze anga asiri akanaka chose, zvisikwa zvakakwanisa kuchinjika kune aya mamiriro uye kurarama.
Ngatimbotaura nezve maruva kutanga. Miti yeOligocene inozivikanwa nenyaya yekuti angiosperms anogona kutanga kupararira kuburikidza nenzvimbo huru dzekugara. Izvi zvinomera zvakatosvika pakudzora kwavanazvo nhasi. Munguva yese iyi nguva, kuderera mumasango enzvimbo dzinopisa kunogona kuonekwa nekuda kwekudonha kwetembiricha yepasi rose. Aya masango anotonhora akatsiviwa nemiti inomera uye huswa hwakashandisirwa kumamiriro ekushisa zvakanyanya. Aya masango uye zvirimwa zvinomera zvinopararira mumakondinendi ese.
Uye izvo ndezvokuti herbaceous zvirimwa zvakave neshanduko huru yeshanduko nekutenda kuchinjika kwehunhu hwavo pachavo mukukura. Izvi zvinomera zvine mwero unoramba uripo wekukura usingamire. Uye zvakare, idzi mhando dzezvirimwa dzaifanirwa kutarisana nekuita kwemhuka dzakasiyana senge mafura anodyiswa padziri. Aya ndiwo maratidziro avanogona kuita akasiyana masimba ekugadzirisa kuti vakwanise kurarama munzvimbo idzi uye kunyangwe kusimbisa hukama hwehukama nedzimwe mhuka. Uye ndeyekuti mhuka zhinji dzakavabatsira kuparadzira mbeu yavo kubudikidza netsvina.
Munguva ino zvakare zvinomera zvemaruva zvakaita sebhinzi zvakagadzirwa.
Kana iri mhuka, kune akawanda mapoka emhuka akakwanisa kusiyanisa uye kuwedzera nzvimbo yavo yekugovera. Zvisinei nemamiriro ekunze avakawanikwa, mapoka mazhinji emhuka dzakaita seshiri, zvinokambaira uye mhuka dzinoyamwisa dzakawedzera kugoverwa kwadzo.
Paive neshiri nezvinokambaira, kunyangwe mukurumbira kwazvo wakatorwa nezvipuka. Izvo zvakakosha kuti uzive kuti iyo Cenozoic inoonekwa seye nguva yezvipuka.
Ndinovimba kuti neruzivo urwu unogona kudzidza zvakawanda nezve Oligocene.