120-Million-Year-Old Pontus Tectonic Plate Unveiled in Asia-Pacific Region

• 14 Oct 2023

Recently, geologists from Utrecht University in the Netherlands have uncovered the existence of the Pontus tectonic plate, which existed 120 million years ago and once covered a quarter of the Pacific Ocean's current expanse.

Key Points

• The Pontus Plate: Named the Pontus plate, this ancient tectonic plate is estimated to have covered a quarter of the present-day Pacific Ocean based on their reconstructions dating back 160 million years.
• It existed during a time when a vast ocean separated Eurasia and Australia, which were part of the supercontinent Pangaea.
• Plate Movement and Breakup of Pangaea: As Pangaea began to break apart, the Pontus plate slowly sank into the Earth's mantle over millions of years as other plates carried regions like Borneo and the Philippines to their current positions.
• Reconstructing Plate Movements: To reconstruct the plate movements, the researchers avoided relying on paleogeomagnetic data due to its scarcity in the region.
• Instead, they considered the western Pacific region and its predecessor, the Panthalassa superocean, which surrounded Pangaea.
• They worked backward from the present-day geological arrangements and adopted the simplest plate tectonic scenario that aligned with geological observations.
• Confirmation of a Predicted Plate: The existence of the Pontus plate confirms predictions made by geologists 11 years ago, based on anomalies in seismic data.
• These anomalies indicated remnants of an old plate that had sunk deep into Earth's mantle, influencing the path of seismic waves.
• Relics of the Pontus plate had also been found in Palawan and the South China Sea, aligning with the geological findings on Borneo.