A big geological discovery has revealed the existence of an ancient tectonic plate that was previously thought to have disappeared. The Pontus tectonic plate, estimated to cover 1 / 4 of the Pacific Ocean, has been rediscovered after about 20 million years.
The remnants of this plate, which once formed the bottom of the South China Sea, can now be traced through rock fragments within the Borneo Mountains, in addition to seismic data indicating the presence of a giant mass of rock within the Earth’s mantle.
Geological mystery within the junction region
The hypothesis of the existence of the Pontus tectonic plate first appeared consequently of the evaluation of geological data carried out by Suzanna van de Lagemaat and her team on the University of Utrecht. Their research focused on the Junction Region, an area of complex tectonic activity within the Asia-Pacific region stretching from Japan, Borneo, the Philippines, Papua New Guinea to New Zealand.
During an in depth study of rocks within the mountains of Borneo, van de Lagemaat identified previously unrecorded plate fragments. This discovery was a significant surprise in the sector of geology since it highlighted the complexity of subduction and mountain formation processes.
Magnetic traces: a key to understanding geological gaps
While trying to find the stays of the traditional Phoenix plate in Borneo, researchers got here across an unexpected discovery. Van de Lagemaat explained that the magnetic properties of rocks can reveal when and where they were formed since the Earth’s magnetic field becomes “locked” into rocks as they form and varies with latitude.
Using computer models to check the region’s geology over the past 160 million years, the team identified a niche between southern China and Borneo. The ocean that was once considered above the traditional Izanagi Plate was not beneath it, but as a substitute rocks from Borneo filled this mysterious void.
Pontus album: a forgotten story
Scientists estimate that the Pontus Plate, a part of the Earth’s crust before the breakup of the supercontinent Pangea, covered a couple of quarter of the Pacific Ocean and lay beneath the ocean separating Eurasia and Australia. It is believed that when Pangea separated, the plate was engulfed by one other tectonic plate, which moved the Philippines and Borneo to their current positions.
Reconstruction published in a magazine Gondwana Studies suggests that the Pontus plate formed at the very least 160 million years ago, and rock samples taken from Borneo date back to 135 million years ago. Though once huge, the Pontus plate regularly shrank and was eventually pushed beneath the Australian and Chinese plates before disappearing 20 million years ago.
Previous research has also indicated the existence of the Pontus Plate through images of the Earth’s mantle, which exposed a big, unidentified plate that has now been confirmed because the remnant of the Pontus Plate.
