Unveiling a Lost Piece of Earth’s History
In a groundbreaking discovery, scientists have identified a 120-million-year-old segment of Earth’s crust, long thought lost, in the region of Borneo. This revelation uncovers the existence of a previously unknown tectonic plate named Pontus. The find was spearheaded by Suzanna van de Lagemaat, a graduate geologist at Utrecht University, alongside her supervisor, Douwe van Hinsbergen, through meticulous analysis of geological data from Asia-Pacific’s mountainous terrains.
Discovering the Pontus plate
Van de Lagemaat uncovered evidence of the ancient Pontus plate while examining rock formations in Borneo. “We thought we were dealing with relics of a lost plate that we already knew about. But our magnetic lab research on those rocks indicated that our finds were originally from much farther north, and had to be remnants of a different, previously unknown plate,” she explained. This unexpected discovery has sparked new interest in the geological history of the region.
The junction region: A complex puzzle
In her quest to understand the Pontus plate, Van de Lagemaat focused on a complicated zone of tectonic activity known as the Junction Region, which includes Japan, Borneo, the Philippines, New Guinea, and New Zealand. Her research involved reconstructing tectonic plate movements in this area since the era of the dinosaurs.
The size and history of Pontus
The Pontus plate once formed part of the Earth’s crust before the breakup of the supercontinent Pangaea. By reconstructing the plate’s movements, scientists estimated that 160 million years ago, Pontus was roughly a quarter the size of the Pacific Ocean. During this period, a vast ocean separated Eurasia and Australia, with the Pontus plate lying beneath it. As Pangaea fragmented, Pontus was subsumed by neighboring plates, which today support regions such as The Philippines and Borneo.
Borneo: A geological marvel
Borneo, the third-largest island globally and part of the Greater Sunda Islands in Southeast Asia, plays a critical role in this discovery. Politically, it is divided among Malaysia, Brunei, and Indonesia. The island’s geological complexity continues to offer vital insights into Earth’s tectonic history.
This discovery not only sheds light on the ancient dynamics of Earth’s crust but also opens new avenues for understanding the geological transformations that have shaped our planet.