Physical Geography

The word Geography has been derived from the Greek word “Geographia”, which consists of two words “Geo” and Graphia”. Geo means the Earth, and Graphia means to write. Collectively Geographia means “Earth Writing”, or Writing about the Earth. The word Geographia was first used by a Greek Philosopher “Eratosthene”, who lived from 274 BC to 194 BC. Geography is a systematic study of the Earth. Before the introduction of the […]

Introduction to Erosion Erosion is a natural geological process that involves the removal and transportation of disintegrated soil and rock particles, or sediment from one location to another by the action of various erosional agents. These agents include water, wind, ice (glaciers), or gravity. It plays a significant role in shaping and featuring the Earth’s surface over long periods of time. Erosion can occur in different environments and landscapes, including […]

Depending upon their mode of formation, the soil deposits have been broadly grouped into two classes: (i) residual soil deposits, and (ii) transported soil deposits. What are different types of Soils? Residual Soil Deposits In plain areas, the products of rock weathering continue to accumulate in places over the parent rock masses and give rise to a “residual soil deposit”. As the action of weathering decreases with depth, such soil […]

The process of Soil formation, which is also known as pedogenesis, is a complex natural phenomenon. It is influenced by various factors such as climate, parent material, topography, organisms, and time. But here we will discuss pedogenesis in different climatic regions. In each region, climate plays a significant role in shaping soil characteristics, resulting in distinct soil types. Here’s a brief overview of how soil formation varies in different climatic […]

Soil is a complex and dynamic natural resource that forms the outermost layer of the Earth’s crust. It serves as a reservoir of minerals, organic matter, water, air, and living organisms. Soil also acts as a medium for the filtration and breakdown of injurious wastes. It also helps in the cycling of carbon and other elements through the global ecosystem. The formation of soil is a result of the weathering […]

The rate at which a rock weathers depends on the following factors. The particle size influences the rate of weathering. The smaller the particles, the greater the surface area for chemical attack. The mineral composition of a rock is also very important. The slate which is mainly composed of clay minerals is very resistant to weathering, while this is not true for marble. The order in which the silicate minerals […]

Weathering is the breakage and detachment of the sediments, particles, and granules from the surface of rocks. Weathering is a continuous and regular process, which is composed of many underlying processes, which are directly concerned with weathering. Weathering: The rocks break and undergo decay under the influence of atmospheric agencies like wind, sun, frost, water, and organisms, and produce soil. This phenomenon is called weathering. Weathering and Erosion together lower […]

What is the Theory of Seafloor Spreading? The theory of seafloor spreading was first proposed by Harold Hemmond Hess in 1960. the two fundamental facts that led him to postulate theory are: (i) the mid-ocean ridge occurs in all major ocean basins, and (ii) the oceanic crust has a thickness of 6 to 7 kilometers only whereas the typical thickness of continental crust is 30-40 km. Hess postulated that the […]

The flow of high heat associated with oceanic ridges proves the existence of “Convection Currents in the Mantle”. These currents are believed to be responsible for the movement of crustal plates. The idea of convection currents was first suggested by a British geologist A. Holmes in 1927 when he tried to explain the driving mechanism for continental drift. Holmes proposed that sub-crustal convection currents dragged the two halves of the […]

The theory of Plate Tectonics has evolved from Harry Hess’s concept of “seafloor spreading”. He proposed this concept in the early 1960s. Hess’s hypothesis was accepted when Vine and Mathews used it in explaining linear magnetic anomalies of the ocean basins. In 1967, W. J. Morgan, and J. T. Wilson extended the idea of Hess and produced the theory of plate tectonics. The factors, which led to the theory of […]