The first evidence of the world ’s oldest let on glaciers has been found in thegoldfields of South Africa . Extremely well - preserve glacial deposits lay beneath the world ’s largest gold deposits , providing convincing evidence of the environmental conditions of the other Earth .
While the exact conditions of Earth during this point are still widely unknown , these 2.9 - billion - twelvemonth - quondam gelid remains could provide evidence for a numeral of theories surrounding shape during this prison term . “ It may be that this arena was close to the poles . Another theory is that the whole Earth was in a ‘ snowball Earth ’ period , when low atmospheric concentrations of CO2and CH4led to a ‘ reverse greenhouse effect ’ , causing much of the satellite to freeze , ” suppose Professor Axel Hofmann , subject field co - writer , in astatement .
“ scientist think that this may have happened on a couple of occasions in the more recent past . If so , this would be the earliest such global cooling system point immortalise . Either possibility is scientifically interesting . ”
Along with the strong-arm grounds of fossilised frigid moraines – the junk left behind by glacier – the squad also analyzed O isotope assiduity in the ancient rocks to settle theclimateconditions at the metre they were fix .
“ We looked at comparative amount of three O isotopes,16O,17O , and18O. These are all types of oxygen but have very slightly unlike weights . We recover that these rocks had very low amounts of18O , and very high amounts of17O , bespeak that they were form at gelid temperatures , ” explained study co - source Professor Ilya Bindeman . “ Couple that geochemical grounds with the moraine evidence , and it means glaciers , the oldest glaciers yet found on Earth . ”
The significance of the location of the finding , beneath the Earth ’s largest sedimentary gold deposition , may also spark further investigating excuse Hofman . “ It ’s possible that a variety from icehouse to nursery weather condition may have aid in the formation of those gilded deposits , but this call for to be substantiate and requires further employment . ”
The employment of triple oxygen isotope depth psychology in this way could add fresh avenues for finding evidence of the early Earth ’s glaciation , with finds like this introducing Modern melody of inquiring and investigating into Earth ’s historical mood .
The study is issue inGeochemical Perspectives Letters .
