WEB DESK: Geologists Cornel de Ronde and Simon Lamb, in their recent publication in Geology on February 27, have revealed groundbreaking evidence of an ancient earthquake, dating back more than 3 billion years, in rocks found in South Africa.
According to Science News, these rocks exhibited distinctive signs of ancient submarine landslides, commonly associated with colossal earthquakes triggered by the collision of crustal slabs.
As per the reports, the discovery sparked renewed debate within the geological community regarding the emergence of plate tectonics – the perpetual movements of Earth’s crustal plates.
The reports said that some experts argued that plate tectonics had emerged no earlier than 2.8 billion years ago, while others maintained it had started even before. The scarcity of rocks from this period made it challenging to pinpoint the exact beginning of plate tectonics.
Meanwhile, Timothy Kusky of the State Key Lab for Geological Processes and Mineral Resources in Wuhan, China, supported the notion that plate tectonics had existed for as long as the oldest preserved rocks on Earth.
The research stemmed from Cornel de Ronde’s prior mapping of rock distributions in the area, published in 2021.
Furthermore, Lamb, upon reviewing the map, noticed striking similarities between the arrangement of ancient rock layers in South Africa and submarine landslides in New Zealand triggered by recent earthquakes.
The comparison suggested that the Barberton rocks in South Africa may have experienced upheaval from massive submarine landslides, a phenomenon typically associated with the aftermath of earthquakes resulting from tectonic plate collisions. The process, known as subduction, could generate powerful megathrust earthquakes, akin to those observed in modern times, such as the 2004 Indonesia earthquake and the 2011 Japan earthquake.
According to Kusky, the study provided some of the earliest evidence for giant subduction megathrust earthquakes, bolstered by fieldwork that relied on tangible, verifiable evidence from the rock record.
However, Richard Palin from the University of Oxford expressed reservations, suggesting that the onset of plate tectonics may not have occurred uniformly across the planet. He proposed that subduction may have commenced at different times and locations on Earth.
