I-Geology ye-Cradle of Humankind

Ukwakheka Kwamatje

©David Fleminger
Amatje wesifunda se-Cradle of Humankind amumethe i-dolomite, eyatlameka embhedeni ongatjhingeliko, emanzini afuthumeleko welwandle avale i- Witwatersrand Basin eminyakeni eyi-3 billion eyadlulako. Amatje we-dolomite enziwe nge-calcium carbonate (limestone) nama-isotopes we-oxygen ambalwa amedwe kuhle. Lokhu kwenza i-Karstic landscape eyenza amadwala ngebanga lokurhurhuleka okuhlala kwenzeka eduze kwamalayini angakalungi ngaphasi kwehlabathi.
Amatje azombeleze i-Sterkfontein kanye ne-Krugersdorp asukela eminhyakeni eyi-2.6 Billion eyadlulako begodu amatje asepumalanga, nawuya e-Krugersdorp aphakanyiswa kokuthoma ekwenza bona ukurhurhuleka kwehlabathi kwenze iintaba ezirolako encenyeni-ye Cradle of Humankind.

Asibone i-Tekhunoloji

Amatje ane-fossil atholakala e-Chuniespoort Group, ye-Malmani Sub-group, ye-Transvaal Supergroup yamatje, begodu enzeka eminyakeni eyi-2.5 billion eyadlulako. The Malmani subgroup ihlukaniswe kahlanu. I-the Oaktree, Monte Christo, Lyttleton, Eccles kanye ne-Frisco Formations. Isifundesi simumethe ikhopha egade yembiwa mihlobo yabantu egade bahlala lapho kade.

Iindlela Zokwemba Nezokubeka Amalanga

©David Fleminger
Njeke, ngemva kokobana i-archaeologist nanyana palaeontologist sele itholile bona kunamatje anama-fossil bawakhipha njani? Ukuwemba kuthatha isikhathi begodu akusilula begodu kutlhoga ukuthwasiswa okuthatha iminyaka nesineke esingapheliko.
Mhlamunye into eqakathekilo ekwembeni kurekhoda bona iinsalela ze-fossil zitholwephi? Nokobana gade ilele njani? gade kuleleni hlanu kwayo? Gade kunani phezu kwazo? Yini egade ingaphasi kwalo? Loke ilwazeli lingakupha ilwazi elingezelelweko ngefosili leyo, ngebhoduluko eliyizombelezileko kanye nepilo engeze warhona ukuyibona nawulithethe ebhokisini kwaphela.
Indaba kukobana ukwemba i-Keyon, begodu kokobana ususe i-breccia nanyana ifosili, angeze wabuyisela godu. Njeke kufanele uhlele bona uzokwemba njani urekhode ilwazi elinengi ngendlela ongarhona ngayo ngefosili oyitholileko ngaphambi kokobana uyisuse uyibeke e-storeroom. Lokhu kubala ukufaka iinthombe nokubeka amanothi wokobana utholeni nawembako, ekumthetho weSewula Africa. Akukafaneli ususe imetheriyali enengi kunaleyo ekufanele uyisuse, begodu kufanele utjhiye ubufakazi ukwenzela bona abarhubhululi bazokuragela phambili ngerhubhululo lokha nabaragela phambili ngokwemba esikhathini esizako.

Ukusebenzisa i-Grid Nokungayisebenzisi

©David Fleminger
Esikhathini esidlulileko ama-archaelogist gade asebenzisa i-grid system ukuhlola bona iinsalela ze-fossil ngezakade kangangani. Le yisistimu lapha uthatha khona iintambo ezinengi uziphambanise uzifake endaweni lapha wemba khona wenze i-square ezibizwa bona ma-spits. Ama-archaelogist emba i-grid ngantokana ezingaba yi-100 cm ngokutjhingela, zuma kumetheriyali, ususe woke amafosili uwabeke eskhwameni emeregwe nge-grid nokutjhingela kwayo.
Le bekuyisitimu esetjenziswa e-Sterkfontein eminyakeni eyadlulako, begodu idrada yakade isabonakala ngaphezu kwalapha bembe khona. Ngendlela le kukobana zoke izinto zibambene begodu awurhoni ukubona bona ini yini.
Iindlela ezitja ze-technology zikhona kuma-archaelogist weskhathi sanje, i-grid system sele iphela msinya nanyana sele ingasasetjenziswa.
Nje sele kusetjenziswa umtjhini obizwa bona yi-Total Station (efana nehlanganisela ye-theodolite kanye – GPS) ama-archaeologist arhona ukurekhoda bona isalela yefosili itholwephi kanye nobude bayo yoke into ebayitholako. Lokhu kukhiqiza ukuthoma kwe-3D erikhodiwa kumazisi ibekwe esikhwameni kanye nefosili.

Ukuluphala Kwayo

©David Fleminger
Kunendlela ezimbili zokwemba: ukwehla nokunyuka. Njengomthetho westhupha, izinto ezitholwa elevelini efanako ziyahlobana lokha ezehlako zitjengisa ubudala (eziphezulu ngezingasizidala, ezitjhingelako ngezidala).
Njeke, ukobana wemba wehle nanyana utjhingele kuya ngokobana umlando wendawo leyo owemba kiyo uthini. Ukuhlolwa kwe-stratigraphy yendawo kuvamise ukufunwa ngaphambi kokobana ubone ubuhlobo bezinto ozembako.
Uthola imihlobo emibili yendlela zokwemba: lezo zehlabathi eloso, nalezo zehlabathi eqinileko, kanye namanye amatje abizwa bona yi-breccia. Ehlabathini eloso, into eqakatheke khulu igarafu yomakhi kanye namabratjhi awakhethileko kanye namapiki. Igarafu isetjenziselwa ukuhlukanisa ihlabathi. Ipiki isetjenziselwa ukwemba ifosili, ibratjhi isetjenziselwa ukubratjha ihlabathi.
Ukumeda kuhle, yoke ihlabathi ezombeleze ifosili iyabuthelelwa isefywe ngesefo esifeyini ukususa ngitjho namathambo afeyini, ayosetjenziswa nanyana ayokuhlolwa e-lab lada.

Ukususwa

Lokha nawusebenza ngamafosili aqinileko, uvamise ukususa ifosili elitjeni usese sendaweni osebenzela kiyo. Kunokwenza njalo, utlhoga ukususa iblogo yamafosili amumethe i-breccia uwase e-lab. Ukwenza lokhu, usebenzisa idrili yesandla ukwenza imigodi embalwa ezombeleze iblogo. Bese ufaka ama-wedge amabili emgodini wembe ngedrili uhlukanise ihlabathi kanye nefosili.
Nawubuyela e-Lab, ungasusa kabuthaka ifosili elitjeni, ngokusebenzisa i-drill nanyana i-asidi esbaga ezokuncibilikisa i-breccia kodwana ingoni ifosili.
Lokha nawufaka amalanga kufosili, kunemihlobo emibili yokuyenza: Kusetjenziswa isayensi yokumeda iskhathi nanyana ihlelo lokubona bona ifosili ngayanini. Yokuthoma ngeyananyana ulinga ukubona bona ifosili yidala nanyana yitja kunezinto etholwe nazo lapho itholwe khona, okwenziwa ngokubala bona ihlabathi yidala kangangani lapho ifosili itholwe khona ngokuhlola bona i-flora nefauna yalapho ifosili itholwe khona yidala kangangani bese kumadaniswa nezinto ezitholwe kwezinye iindawo. Ngaphambi konyaka ka-1960 ukuhlola bona into yidala kangangani kwakwenziwa ngendlela le. I-Chronometric dating yona kuhlolwa bona ifosili yidala kangangani ngokubala bona i-carbon ekhona kufosili ngeyanini imadaniswe naleyo eyaziwako nezinga lokubola kwekhemikhali.
Indlela ye-radiometric le ingameda i-pottasim argon (K-Ar) carbon (kwaphela nange ifosili etholiweko ineminyaka engaphasi kwe-50 000 ubudala) kanye nezinye izinto ze-radioactive. Kunanendlela ebizwa bona yi-Paleo magnetism ehlola ezinto ezingaphakathi kwefosili ukumeda kobana suduke kangayingakhi i-magnetic field esephasini (nekuyinto eyenza ngemva kweminyaka embalwa emakhulu).

Translated by Busisiwe Skhosana