Question

Choose the right answer Column I - Scientist Column II - Contribution

Alfred Wegener	Plate Tectonic Theory
Harry Hess	Mantle Convection Hypothesis
Arthur Holmes	Sea-floor Spreading
McKenzie and Parker	Continental Drift Theory

• A. A-4, B-3, C-2, D-1
• B. A-3, B-4, C-1, D-2
• C. A-2, B-1, C-4, D-3
• D. A-1, B-3, C-4, D-2

Answer 1

Answer:

A. A-4, B-3, C-2, D-1

• Alfred Wegener (1912): Proposed the Continental Drift Theory. He suggested that all continents were once joined together in a supercontinent named Pangaea and subsequently drifted apart. He provided evidence based on fossil distribution and rock formations across different continents.
• Arthur Holmes (1928): Proposed the Mantle Convection Hypothesis. He argued that thermal convection currents within the Earth's mantle provide the driving force for the movement of continents. This provided a crucial mechanism for Wegener's drift theory, which initially lacked a clear physical cause.
• Harry Hess (1960): Developed the Sea-floor Spreading hypothesis. While serving as a naval officer, he used sonar data to map the ocean floor, identifying mid-ocean ridges and deep-sea trenches. He proposed that new oceanic crust is continuously created at mid-ocean ridges and destroyed at subduction zones.
• McKenzie, Parker, and Morgan (1967): Formulated the Plate Tectonic Theory. They synthesized previous ideas to explain that the Earth's outer shell (lithosphere) is divided into several rigid plates that glide over the plastic asthenosphere. This theory serves as the unifying concept in modern geology, explaining earthquakes, volcanic activity, and mountain building.