Ngaphakathi kokuma komhlaba kunegatsha elibizwa ngokuthi i-stratigraphy Lokho ekwenzayo ukutadisha ubukhulu bezintambo bese unikeza amadwala iminyaka. Ngaphakathi kwaleli gatsha kunelinye igatsha elikhethekile elibizwa ngokuthi umagazine. Izazi ze-geologists zikwazile ukusungula iminyaka ehlobene yamatshe e-sedimentary ngenxa yezimiso ze-stratigraphic kanye nomgomo wokufana. Kodwa-ke, ukuze kwakhiwe ikholomu ye-stratigraphic yomhlaba wonke, elinye ithuluzi liyadingeka ukuze kutholwe iminyaka yazo zonke izigaba ezihlukene ezingxenyeni ezihlukene zomhlaba futhi zihlobanise enye kwenye. Yilokhu okushiwo yi-biostratigraphy.
Kulesi sihloko sizokutshela konke odinga ukukwazi ngaleli gatsha lesayensi.
Kufundani i-biostratigraphy
Leli gatsha lesayensi lazalelwa ukuxazulula ezinye zezinkinga eziphakanyisiwe ngenkathi kusungulwa iminyaka yamatshe kanye nayo yonke ikholomu yomugqa womhlaba. Izazi zesayensi yokwakheka komhlaba zakudala zaphakamisa umgomo wokulandelana kwezilwane kulandelana ngokweqile. Lo mgomo wokulandelana kwezilwane usitshela lokho Amayunithi we-lithological kufanele ethule uchungechunge lwezinsalela zeminyaka yobudala bazo. Lezi zinsalela aziveli kuphela kule yunithi kepha kufanele ziphindwe kokunye nakokunye. Imivubukulo ephawuleka kakhulu kufanele yehluke futhi ibuye ibonakale ezinhlotsheni ezahlukahlukene zamadwala entlenga.
Izinsalela ezimele kakhulu zingcono kakhulu ezisebenza ukubamba iminyaka yobudala yamadwala. Le mivubukulo ebaluleke kakhulu ibizwa ngama-index fossil. Ziyaziwa futhi ngamagama ezinsalela zomhlahlandlela. Le mivubukulo yethulwe ngendlela eyandisa indawo yonke ngokwendawo. Zivame kakhulu futhi zivame ukulondolozwa kahle. Ngaphezu kwalokho, zonke izinhlobo kufanele zivele ngesikhathi esifushane. Kodwa-ke, uhlobo nalo lungaziveza esikhathini eside esandisiwe.
Kumele kukhunjulwe ukuthi, ukuze sibe neminyaka yalezi zifundo, kufanele sisebenzise i- isikhathi sokuma komhlaba. Lesi sikhathi sokwakheka komhlaba yiso esiphawula inkathi lapho izinhlobo zezilwane zivela futhi zisakazeke cishe esikhaleni sesikhathi esifanayo. Kuwo wonke umlando kanye nezinkathi zokuma komhlaba ezenzeke emhlabeni wethu, kukhona lezo lapho ukushabalala okukhulu kwenzeke khona emhlabeni wonke, njengoba kuchazwe kabanzi esihlokweni esithi. zonke izikhathi ze-geological, kufaka phakathi i- I-Permian futhi i I-Devonian.
Kumele siqhathanise imininingwane izinsalela zezinkomba ezisinika yona, izinsalela ze-facies okuyilezo ezibonakala zihambisana nedwala elithile. Lezi zinsalela ziye zahlala cishe zingashintshile isikhathi eside. Ngaphezu kwalokho, ubudlelwano balezi zinsalela kanye Miocene inganikeza ulwazi olubalulekile mayelana nesikhathi esidlule sokwakheka komhlaba.
Ama-biohorizons nama-biozones
Yimiqondo emibili esungulwe egatsheni lesayensi elibizwa nge-biostratigraphy. Lokhu kusho ukuthi insalela ngayinye ivela eqenjini elithile lendlela. Akukho edwaleni elitholakala ngaphakathi nendawo nasengxenyeni engenhla yekholomu ye-stratigraphic okufanele liqukethe izinsalela zalesi silwane futhi. Izakhiwo ze-lithological yilezo ezinciphisa ubukhona bezinsalela futhi zibizwa ngokuthi ama-biohorizons. Njengoba igama layo liphakamisa, kukhombisa indawo lapho leyo fossil yayikhona ngaphandle kokunye.
Kunezinhlobo ezimbili zama-biohorizons. Ngakolunye uhlangothi, kukhona ababukeka okokuqala, ngakolunye uhlangothi, ababukeka bokugcina. Ngokuvamile, uhlobo oluthile luyaguquguquka futhi kancane kancane luyayeka ukuba khona. Ukwehlukana lezi zinhlobo ngokuvamile okuba nazo kulandela indlela yokuziphendukela kwemvelo. Uma uwuhlaziya usebenzisa ama-horizons uyabona ukuthi asabalele. Nokho, ngezinye izikhathi kwakuyizinqubo zokuqothulwa kwabantu abaningi, njengoba sishilo ngaphambili, okwabangela ukuba amaqembu amaningi ezilwane nezitshalo aqedwe ngesikhathi esifushane. Isibonelo salokhu ukushabalala okukhulu kwama-dinosaurs okubonisa ukuphela kwenkathi ye-Cretaceous, isenzakalo esihlobene futhi nezinye izenzakalo ze-geological.
Ama-Biohorizons yilawo amaka ukuqothulwa kwesisindo futhi acace bha. Ngakolunye uhlangothi, sinama-biozones. Lawa ngamayunithi we-lithological aletha inkomba yezinsalela noma okuqukethwe kwe-paleontological okubaluleke kakhulu. Sinezinhlobo ezithile zama-biozones:
- Ama-biozone esewonke yilezo ezimele ukuhlangana kwezinsalela eziningana ngokwemvelo ngaphakathi kwesigaba se-stratigraphic.
- Ama-biozones wokucindezeleka yilezo ezihambelana nama-biozone akhula ngokuvundlile noma ngokuvundlile. Imaka umehluko phakathi kwamacu.
- Ama-biozone we-apogee yilezo ezimaka ubuningi obukhulu bezinhlobo, uhlobo lomndeni ngisho nomndeni. Lokhu kukhethekile kakhulu.
- Ama-biozone wesikhawu yilawo amele amadwala phakathi kwama-biohorizons amabili ezinsalela ezihlukene.
Ukubaluleka kwesikhathi se-geological ku-biostratigraphy
Lesi sikhathi se-geological sikhona kuzo zonke izifundo ze-stratigraphic. I-Biostratigraphy ibiyithuluzi elihle kakhulu elisisize ukubhekana nobudala bamadwala ngendlela ehambisanayo. Onke amadwala ase-sedimentary ezingeni lomhlaba wonke aphethwe futhi, ngaphezu kwalokho, asize ekwakheni isigaba se-stratigraphic world. Yonke imininingwane ihlobene futhi ayishongo lutho mayelana nobudala bomhlaba. Ngakho-ke, ososayensi bazozama ukubala le minyaka besebenzisa i-biostratigraphy.
Kukhona ucwaningo oluningi nososayensi abanikeze imibono ehlukene mayelana nendlela yokubala ubudala beplanethi yethu. Lokhu kuhlola kwadala impikiswano enkulu nenkulumo-mpikiswano, njengokuthile okusikisela ukuthi iplanethi enguMhlaba yayineminyaka engu-75.000 XNUMX kuphela ubudala. Udaba lwagcina luxazululwe ngocwaningo lwemisebe kanye nokuhlolwa kokubhukuda kwe-radiometric. Ngale ndlela, okuqukethwe kwezakhi ze-radioactive kanye nokuhlakazeka kwazo kwezinye izakhi kuye kwafundwa. Lokhu kwenzeke ngenxa yokubala iminyaka ephelele yamadwala entaba-mlilo kanye nobudlelwano bawo ne-volcanic rocks. Isi-Silurian.
Le minyaka ebaliwe ingezwa esikalini esihambisanayo kanye nesilinganiso sesikhathi se-geologic esaziyo namuhla ukuthi sidaliwe. Lesi silinganiso yiso esikhomba ulwazi lweplanethi yethu cishe cishe eminyakeni eyizigidi eziyizinkulungwane ezingama-4.600 edlule kanye nokuvela kwamadwala okuqala asalondolozwe cishe iminyaka eyizigidi eziyizinkulungwane eziyi-3.600.
Njengoba ukwazi ukubona, izinsalela zamathambo ziyithuluzi elikhulu lokufunda ngomlando weplanethi yethu. Ngiyethemba ukuthi ngalolu lwazi ungafunda kabanzi ngokusetshenziswa okuhle kwe-biostratigraphy.
