Relief of the Ocean Floor
The oceans occupy the depressions of the Earth’s outer layer, and their topography is complex and varied. Geographers have divided the oceanic part of the Earth into five oceans: the Pacific, Atlantic, Indian, Southern, and Arctic oceans, along with various seas, bays, gulfs, and inlets. The ocean floor, situated between 3-6 km below sea level, displays diverse features similar to those on land, including mountain ranges, trenches, and plains, shaped by tectonic, volcanic, and depositional processes.
The ocean floors can be categorized into four major divisions: the Continental Shelf, the Continental Slope, the Deep Sea Plain, and the Oceanic Deeps. Additionally, there are various relief features such as ridges, hills, seamounts, guyots, trenches, canyons, and atolls.
- The Continental Shelf: This is the shallowest part of the ocean, extending from each continent and typically ending at a steep slope known as the shelf break. It varies in width and depth, covered with sediments that accumulate over time and become a source of fossil fuels.
- The Continental Slope: Connecting the continental shelf to the ocean basins, the continental slope is a steep region with varying gradients and depths, featuring canyons and trenches.
- Deep Sea Plain: These are gently sloping areas of the ocean basins, characterized by fine-grained sediments like clay and silt, and depths ranging from 3,000 to 6,000 meters.
- Oceanic Deeps or Trenches: These are the deepest parts of the oceans, occurring at the bases of continental slopes and associated with active volcanoes and strong earthquakes. They play a significant role in the study of plate movements.
In addition to these major divisions, there are minor relief features like mid-oceanic ridges, seamounts, submarine canyons, guyots, and atolls. These features contribute to the diverse and dynamic nature of the ocean floor.
Water (Ocean)| Class 11 Chapter 12 Geography Notes
The Ocean Water is the salty water that makes the whole ocean and sea. It is the primary component of the Earth’s hydrosphere which accounts for almost 97% of the Earth’s water. The ocean and sea are the important habitats for so many species of the Earth. It is a complex mixture of 96.5 percent water and 2.5 percent salts. Some smaller amounts of other substances, including dissolved inorganic and organic materials, particulates, and a few atmospheric gases are also present in the Ocean Water.
In this article, we are going to discuss the Water of the Ocean in detail.
Water (Ocean)| Class 11 Chapter 12 Geography Notes