Formation of the Western
Are you ready to go back in time and space? Close your eyes and picture the late Cretaceous period (145–66 million years ago, with dinosaurs and prehistoric crocs!). The formation of the Western Ghats is linked with a geological event known as the Deccan Trap eruptions, which took place in this era…
Today, we know that Earth’s land masses are divided up into seven continents. Not long ago, most scientists presumed that these continents—Earth’s crust—were permanently fixed on the outer layers of the globe. But in 1912, scientist Alfred Wegener theorised that these continents were actually all once joined together, then broke apart, and are now slowly drifting across the Earth! He noticed that all of Earth’s present-day continents seemed to fit together like a jigsaw: not only did the land masses correlate, but he also found clues amongst the world’s plants, animals, rocks and mountains that indicated they were all once found together on a supercontinent called Pangaea. Today this Continental Drift Theory—and how it gave rise to landforms like the Western Ghats—is generally accepted, but it was highly controversial at the time!
Another scientist with similar ideas was Eduard Suess. He became fascinated with a plant genus called Glossopteris, which emerged during the early Permian period (299 million years ago (mya)). When Glossopteris fossils were found in Australia, Antarctica, India, South Africa, and South America—all the southern continents—Suess used this to suggest that these continents must all have been connected together at one point, before moving apart to their current positions.
What is the field of study involving analysis of the fossilised remains of plants or plant pollen called?
Continental Drift & The Western Ghats
We now know that Earth’s land masses are constantly shifting and changing due to subterranean movements called plate tectonics. In fact, over the course of Earth’s lifespan, several supercontinents like Pangaea have probably formed and broken up! Let’s take a look at how such processes give rise to geological formations like the Western Ghats.
Land masses drifted together to form one supercontinent called Pangaea.
Pangaea split, creating two new supercontinents—Laurasia and Gondwanaland. Modern-day Antarctica, South America, Africa, Arabia, Australia, Madagascar and India were part of Gondwanaland, while the remaining continents were in Laurasia. A widespread warming of Earth’s climate ensued, allowing for new forms of life.
Gondwanaland itself began to fracture, splitting into various smaller continents. India, Madagascar, and the Seychelles Islands were cut adrift in this process.
The Indian plate began to drift from Madagascar, pushing northwards towards the much larger Eurasian plate. As the Indian plate passed over the newly formed Carlsberg Ridge in the Indian Ocean, the Seychelles began to separate from India, spawning the violent Deccan Traps eruptions.
These volcanic eruptions thrust basalt upwards, penetrating through the crust of the Indian plate. Basaltic floods began to layer and stack, creating vast deposits. The pressure also initiated the uplift of what we today know as the Western Ghats.
India rammed into Eurasia, giving us the map we’re familiar with today.
Which is the older mountain range?
Spot on! Try again! The Himalayas only emerged 40–50 mya—when the drifting Indian plate collided with the larger Eurasian plate—buckling and folding to create the world’s tallest mountain range!