The Barberton Greenstone Belt in South Africa contains some of the oldest give away rocks on Earth , some over 3.6 billion years old . It also contain some layers , a moment younger than that , which have perplexed geologists as they looked like a jumble of unlike rock put together . researcher now have a proposition : That portion is grounds of an ancient submarine landslide cause by an ancient quake .
If their theory is correct , this is the old evidence of an earthquake . The rocks are lot of an ancient and deep seafloor aged about 3.3 billion years . But among them , there are sedimentary stone that could not have formed on the ocean trading floor . Those are rocks that take form either onland or in shallow water , such as barite crystals that formed as evaporites – rocks produced by the vaporization of water . Definitely not something that materialise at the bottom of the sea .
So , the interrogation is : how did those very unlike types of rock get together ? Researchers Simon Lamb and Cornel de Ronde realized that the mix of rocks resemble the structures see off the coast of New Zealand , where powerful earthquakes produce the kind of nautical landslide that get material from dry land and shallow water onto the recondite ocean story .
“ We realised this map look remarkably alike to a geological map ( by Simon Lamb ) made of the consequence of much more recent submarine landslides . These were trigger by great earthquakes along New Zealand ’s largest shift , the megathrust in the Hikurangi subduction zona , ” the generator wrote inThe Conversation .
“ The importance of this lies in the fact that New Zealand ’s geological record book is uniquely created by the profound effects of big earthquakes in a subduction zone . This is still happening today , most recently in November 2016 , when the magnitude 7.8 Kaikoura earthquake set off vast submarine landslip and debris avalanches that flowed down into recondite water , ” the authors go on . “ We detect the oldest disc of these earthquake , hide in the highveld of southern Africa . ”
This conjecture is uniform with grounds from other region of the world that plate tectonics and quakes from the apparent motion of the crustal plate originate aroundthat time . But there ’s more . The Barberton Greenstone Belt shows evidence of underwater volcanism standardised to the dramaticHunga Tonga - Hunga Ha’apaivolcanic eruption .
It is believed that the tumult of our planet play an important theatrical role in the establishment oflife on Earth – although life might have predated the formation oftectonic plates .
A newspaper publisher on this work is issue in the journalGeology .
[ H / T : The Conversation ]
