What is Continental Drift Theory?

The Continental Drift Theory explains how Earth's continents slowly moved over time. This idea was first shared by Alfred Wegener in 1912. He believed that all continents were once joined together in one enormous landmass called Pangaea. Over millions of years, this land broke apart, and the pieces drifted to their current places. Wegener noticed that the east coast of South America fits perfectly with the west coast of Africa, like puzzle pieces. He also found similar fossils and rocks on different continents, which supported his theory.

For example, fossils of the same ancient plants and animals were found in both Africa and South America. This showed that these lands were once connected. Continental Drift Theory helped scientists understand how mountains formed and why earthquakes happen. Today, it is part of a larger concept called Plate Tectonics, which explains how the Earth's surface changes.

What is Continental Drift Theory?

The Continental Drift Theory was first proposed by German scientist Alfred Wegener in 1912. He suggested that the continents were once joined together in a single supercontinent called Pangaea, about 200–250 million years ago. 

Over time, this landmass broke apart, and the continents slowly drifted to their present positions. Wegener supported his idea with several pieces of evidence. For example, the coastlines of South America and Africa fit together like puzzle pieces, suggesting they were once connected. 

Fossil studies have also revealed similarities, such as the remains of the reptile Mesosaurus, which were found in both South America and Africa, despite the ocean separating them today. Geological evidence, like similar rock formations and mountain ranges on different continents, also supported the theory. 

At first, scientists rejected Wegener's idea because he could not explain the force that moved the continents. Later studies in the 1960s, such as seafloor spreading and plate tectonics research, proved that Earth's lithosphere is broken into plates that move slowly due to convection currents in the mantle. 

This confirmed Wegener's idea in a broader sense. Today, the Continental Drift Theory is seen as the foundation of the modern Plate Tectonic Theory, explaining earthquakes, volcanoes, and mountain formation.

What is Plate Tectonic Theory?

The Plate Tectonic Theory, developed in the 1960s, expanded on Alfred Wegener's Continental Drift Theory by explaining how and why continents and oceans move. It states that the Earth's outer shell, called the lithosphere, is broken into large pieces called tectonic plates.

These plates float on the semi-molten layer beneath, known as the asthenosphere, and move slowly due to convection currents in the Earth's mantle.

Unlike Wegener, who could not explain the driving force, plate tectonics provides the scientific mechanism for movement. This theory explains major geological events. For example, when two plates collide, they form mountain ranges like the Himalayas.

When they move apart, new crust is formed, as seen in the Mid-Atlantic Ridge. Similarly, sliding plates cause earthquakes along boundaries such as the San Andreas Fault in California. Studies of seafloor spreading, palaeomagnetism, and satellite tracking strongly support this theory.

Plate tectonics not only confirms the movement of continents but also explains the creation of oceans, volcanic activity, and the cycle of crust formation and destruction. Together with the Continental Drift Theory, it gives us a complete picture of Earth's dynamic surface and how our planet is constantly reshaping over millions of years.