Grade 9 Geography: Surface Forces that Shape the Earth and Resource Sustainability

Comprehensive vocabulary flashcards covering the Grade 9 Geography Cycle Test topics on surface forces (weathering, river landforms, oceanography, ice and wind erosion) and resource use and sustainability.

Weathering

The breakdown and decomposition of rocks at or near the Earth's surface through biological, physical, or chemical processes.

Biological weathering

A form of weathering caused by living organisms, such as plants and animals, breaking down rock.

Physical weathering

A mechanical process that breaks rocks into smaller fragments without altering their chemical composition.

Chemical weathering

The breakdown and alteration of rock minerals through chemical reactions.

Erosion

The wearing away and removal of rock, soil, or sediment by natural forces such as water, wind, ice, attrition, and abrasion.

Deposition

The geological process where eroded materials and sediments are dropped or laid down by water, wind, or ice.

River profile

The cross-section or slope of a river from its source to its mouth, divided into the upper course, middle course, and lower course.

Upper course

The earliest, steepest stage of a river where vertical erosion dominates, forming landforms such as v-shaped valleys, waterfalls, and rapids.

Middle course

The intermediate stage of a river with gentler slopes, where lateral erosion and transport occur, forming features like meanders.

Lower course

The final stage of a river near its mouth characterized by low gradients and significant deposition, forming flood plains, oxbow lakes, and deltas.

Waterfalls

Steep drops in a river's upper course where water plunges vertically over a hard rock ledge.

Rapids

Sections of fast, turbulent water in a river's course caused by steep gradient changes and exposed bedrock.

V-shaped valleys

Narrow valleys with steep, sloping sides carved by vertical water erosion in a river's upper course.

Meanders

Pronounced winding loops or bends that develop along the middle and lower courses of a river.

Oxbow lake

A U-shaped body of water formed when a meander neck is breached and isolated from the main river channel.

Flood plains

Broad, flat areas of land adjacent to a river that become submerged during floods and are layered with rich deposited sediment.

Delta

A low-lying depositional landform created at a river's mouth where it deposits sediment upon entering a standing body of water.

Abrasion

A mechanical erosion process where rock particles carried by water, wind, or ice scrape and grind away surrounding surfaces.

Attrition

A process of erosion where transported rock fragments collide against one another, breaking down into smaller and rounder pieces.

Sea cliffs

Steep rock faces along a coastline sculpted by relentless wave erosion at their base.

Headlands

Hard, resistant coastal rock sections that jut out into the ocean because they erode slower than adjacent softer rock.

Bays

Curved, sheltered coastal inlets formed where softer rock has been eroded inland by wave action between headlands.

Sea caves

Deep coastal hollows eroded into weak zones or cracks of headlands and cliffs by wave action.

Arches

Coastal landforms formed when wave erosion cuts completely through caves on both sides of a narrow headland.

Stacks

Isolated vertical columns of coastal rock left standing in the sea after an arch collapses.

Stumps

Short, low remnants of rock that remain after a sea stack is worn down by continuous wave erosion.

Wave-cut platforms

Wide, gently sloping rocky benches formed at the foot of eroding sea cliffs, typically exposed during low tide.

Beaches

Coastal deposition landforms made of loose sand, gravel, or pebbles accumulated along the shore by wave action.

Spits

Long, narrow ridges of sand or shingle deposited by waves that extend out from the coast into open water.

Tombolos

Depositional ridges of sand or shingle connecting an offshore island directly to the mainland.

Glaciers

Massive bodies of slow-moving ice that act as powerful agents of ice erosion and landscape shaping.

Horns

Sharp, pyramid-shaped mountain peaks formed by ice erosion from multiple cirque glaciers eroding inward.

Aretes

Sharp, knife-edge rocky ridges created between two adjacent glacial valleys or cirques.

Cirques

Steep-sided, bowl-shaped amphitheater hollows carved into high mountainsides by glacial ice erosion.

Moraine

Accumulations of unsorted rock, gravel, and debris transported and deposited by a glacier.

Mushroom rocks

Arid landscape rock formations with narrow pedestals and broad tops, shaped predominantly by wind erosion.

Soil erosion

The removal of the topsoil layer, which is heavily accelerated by human activities including agriculture, construction, and mining.

Renewable resources

Natural resources that can replenish or regenerate naturally over time at a rate equal to or faster than their consumption.

Non-renewable resources

Natural resources that exist in finite amounts and cannot regenerate on a human timescale once depleted.

Overgrazing

An unwise use of land resources where excessive livestock grazing strips vegetation cover and triggers severe soil erosion.

Sustainable farming

Agricultural production methods that combine good farming techniques and appropriate technology to protect soil and natural resources for future generations.