Millions of years ago, when Earth was still finding its way to what it is today, it was quite literally a blue planet.The Earth was covered with raging oceans all over its huge sphere, which disappeared over the ages, leaving traces throughout the continents, giving rise to mountains and various other landforms.Researchers at the University of Adelaide have put together this puzzle using decades of rock data, going far beyond what we already know.
The lost Tethys sea behind the modern landscape
The disappeared Tethys sea that existed millions of years ago
New research published by University of Adelaide scientists in Communications Earth & Environmental shows that Central Asia’s diverse landforms originate from the ancient Tethys Ocean, which closed during the Mesocene Era and spans approximately the past 250 million years.This huge ocean then shrank and became the modern Mediterranean Sea. It sent tectonic ripples deep inland, reactivating ancient fault lines and creating mountains and rugged highlands in regions such as Kazakhstan, Uzbekistan and western China. According to lead author Dr Sam Boon, a former postdoctoral fellow at the University of Adelaide, “Rather, the dynamics of the distant Tethyan Sea may be directly correlated with short-term mountain building movements in Central Asia.”The team’s extensive dataset has compiled hundreds of thermal history models from 30 years of research, tracking how rocks cool during uplift and erosion, revealing these hidden pulses.
dinosaur lived in the mountains millions of years ago
The current appearance of Central Asia is largely due to the collision between India and Eurasia, but dinosaurs in the Cretaceous period likely roamed on similarly rugged terrain.“However, during the Cretaceous period, dinosaurs would have also seen mountainous landscapes similar to what is now the Basin and Range Province of the western United States,” said co-author Stein Glory, associate professor at the university’s School of Physics, Chemistry and Earth Sciences.
Asia’s steep fault line
He added: “Expansion of the Tethyan Range by unwinding of a slab of subducting oceanic crust is thought to have reactivated an old suture zone into a series of near-parallel ridges in central Asia up to several thousand kilometers away from the Himalayan collision zone.”Forces from the distant ocean affected ancient geological seams, sculpting ridges and basins millions of years before the great uplift of the Himalayas began.
Older theories inferred that this was due to climate change
Previous theories held that a combination of collisions, mantle flow, and climate change were responsible for the formation, but the region has remained largely dry for most of the past 250 million years.“We find that climate change and mantle processes have had little impact on the landscape of Central Asia, which has had an arid climate for most of the past 250 million years,” Dr. Boone explains. In fact, remote Tethyan tectonic movements were the main driving force behind these changes.