Geography Chapter on Landforms and Erosion

Lithospheric Plates and Earth Movements

• The lithosphere is divided into plates
• These plates move slowly, a few millimeters per year
• Movement is caused by molten magma flowing in a circular pattern within the Earth
• Plate movement causes changes on the Earth's surface

Endogenic and Exogenic Forces

• Forces that act inside the Earth are called endogenic forces
• Forces that work on the Earth's surface are called exogenic forces
• Endogenic forces can cause sudden or slow movements
• Examples of sudden movements are earthquakes and volcanoes, causing significant destruction
• Examples of slow movements are gradual changes in landforms

Volcanoes

• A volcano is an opening in the Earth's crust
• Molten material erupts suddenly through this opening (vent)
• Molten material (magma) travels from a chamber under the Earth's surface, to the surface

Earthquakes

• Earthquakes are vibrations on the Earth's surface
• They start at the focus (origin) deep within the Earth's crust
• These vibrations spread outwards as waves, originating at the epicenter (the point on the surface directly above the focus)
• Earthquakes can be measured on the Richter scale

Weathering and Erosion

• Weathering is the breaking down of rocks on the Earth's surface
• Erosion is the wearing away of the landscape by factors like wind, water, and ice
• Erosion and deposition create varied landforms on the Earth's surface

Work of a River

• Rivers erode the landscape as they flow
• Rivers carve valleys and create waterfalls around obstacles
• As rivers meander through plains, they form meanders
• In time, meanders can cut off and form oxbow lakes
• Rivers can deposit sediments, forming floodplains

Work of Sea Waves

• Sea waves continuously strike coastal landforms
• Rocks are eroded, forming cracks and cavities, creating caves and arches
• Deposition of sediments by waves creates beaches.
• Stacks and sea cliffs are other features formed by waves

Work of Ice (Glaciers)

• Glaciers erode the landscape by bulldozing soil and rocks
• They create hollows that eventually may fill with water, forming lakes
• Sediments (debris), rocks, sand and silt are deposited from melting glaciers, forming moraines

Work of Wind

• Wind is an agent of erosion and deposition in deserts
• Wind can shape rocks into mushroom forms (mushroom rocks)
• Wind carries fine sand grains, depositing them in large areas as loess
• Wind also creates sand dunes

Test your knowledge on various geographical landforms and the processes that create them. This quiz will challenge your understanding of flood plains, erosional features of sea waves, and more. Perfect for students exploring Earth Science concepts.