River Dynamics and Erosion Quiz

A steep rock face formed on the outside bend of a river meander due to erosion by fast-flowing water.

A gently sloping area of sediments found on the inside bend of a river meander where deposition occurs.

A flat, low-lying area on either side of a river that is covered by the river during floods and contains alluvium deposits.

A narrow, V-shaped valley with steep sides, formed at the upper course of a river where the gradient is steep and the river flows rapidly.

The force of water eroding the river bed by direct impact and pressure.

Erosion caused by rock particles carried by the river, grinding and scraping against the river bed.

Chemical weathering of rocks by the river's water, dissolving and breaking them down.

Waterfalls occur when a river flows over hard rock that lies above softer rock, gradually undercutting the soft rock and creating a drop.

Rock that is harder and less easily eroded, often found at the base of waterfalls.

Rock that is easily eroded by the river, often found above the resistant rock in waterfalls.

The deep basin at the base of a waterfall, formed by the impact of falling water.

Rapid, turbulent water flow over steep, resistant rocks in a riverbed, caused by uneven erosion of soft and hard rocks.

Deep, narrow, and steep river valley formed by a retreating waterfall.

Ridges of hard rock projecting into a river valley, causing the river to bend and create a zig-zag pattern.

Rapids are formed when a river flows over alternating layers of hard and soft rocks. The softer rocks erode faster, leaving behind resistant rocks that cause the water to flow rapidly.

A plunge pool forms when falling water from a waterfall erodes the soft rock at the base, deepening the pool. Collapsing overhangs also contribute to the erosion.

A gorge is formed by the backward erosion of a waterfall. The waterfall undercuts the soft rock, causing the hard rock overhang to collapse and retreat upstream.

Interlocking spurs are formed when hard rock ridges on both sides of a river valley project into the river channel, causing the river to bend around them.

A low-lying area formed by a river overflowing its banks, depositing sediment, and building up over time. It often includes swampy areas.

A low-lying swampy plain formed at a river's mouth where it enters a sea or lake. It's created by the deposition of sediment, often forming land over time.

Conditions required for a delta to form include low tides, a constant supply of sediment, slow river velocity, shallow water, and a faster deposition rate than erosion.

Branches of a river that form within a delta as the river's main channel gets blocked by sediment deposition, causing the water to find new routes to the sea.

A delta shaped like an arc or a fan, characterized by coarse sediment, multiple distributaries, and a curving shape.

A body of water formed within a delta when a distributary is blocked off by sediment, creating a still water area.

A swampy area formed within a delta as a lagoon fills with sediment over time, creating a wet, muddy environment.

The process by which a delta gradually dries up, turning into land as sediment continues to fill in the swampy areas.

A delta with finger-like projections extending into the sea. It forms from fine sediments and has few river branches (distributaries).

Formed along a submerged river mouth due to strong wave action, causing sediments to spread evenly. It is partially submerged and has both salt and fresh water.

A river with multiple, interconnected channels separated by small islands (eyots) formed due to sediment deposition during low flow periods.

When a river has a high flow or volume, it carries a large amount of sediment. However, when the flow is low, it deposits the sediment, splitting the river into smaller channels.

A crescent-shaped lake formed when a meandering river erodes its outer bends and deposits sediment on its inner bends, eventually cutting off a loop of the river.

The process of erosion that happens sideways (along a river's bank) in a meandering river, primarily on the outer bend due to faster water flow.

Sediments are deposited on the inner bend of a meandering river where the water flows slower. This builds up the land on the inside of the bend.

Lateral erosion on the outer bend and deposition on the inner bend of a meander can create a narrow neck of land. Over time, this neck erodes away, cutting off the loop and creating an oxbow lake.

Meanders form as a river flows over a gentler gradient, depositing heavy sediment due to reduced energy. The river then flows around this obstacle, creating a winding path. Erosion on the outer bend and deposition on the inner bend further enhance this winding pattern.

Outer bend of a meander experiences faster flow, leading to erosion. Inner bends have slower water flow, causing deposition.

Potholes are circular depressions in a riverbed caused by spinning rocks. Water turbulence forces rocks to grind against the riverbed, gradually carving out these holes.

Potholes form when rocks, carried by flowing water, swirl in circular motion within uneven riverbeds. The grinding action of these spinning rocks creates the depressions.

Erosion that occurs downwards in a river channel, primarily responsible for the formation of V-shaped valleys.