upsc notes

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    Plate Tectonic Theory

    The Plate Tectonics Theory is one of the most revolutionary ideas in the field of Earth Sciences — just like Newton’s laws in Physics or Darwin’s theory in Biology. This theory explains why earthquakes happen, how mountains are formed, why volcanoes erupt, and how continents have drifted over millions of years. 👉 This theory was…

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    Sea Floor Spreading Theory

    In the 1950s, undersea mapping shattered the myth that ocean floors were flat and featureless. Instead, scientists discovered rugged landscapes with vast mountain chains and deep trenches. Key Observations from Seafloor Mapping: These discoveries set the stage for Harry Hess’ revolutionary theory of Seafloor Spreading in 1960. 🚀 What is Seafloor Spreading? Harry Hess proposed…

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    Convection Current Hypothesis

    Arthur Holmes in 1928-29 proposed this theory to explain the origin of major relief features of the Earth’s surface, such as mountains, ocean basins, and continents. Holmes believed that the Earth’s interior was dynamic, and convection currents within the mantle were responsible for the movement of continents and landforms. Key Concepts of Holmes’ Hypothesis 1….