Deltas and Stream Characteristics

The video explains stream evolution, focusing on young, mature, and old streams. Young streams are found in steep valleys with high energy, while mature streams have wider valleys and floodplains. Old streams have broad floodplains and low energy. The formation of oxbow lakes from meanders is discussed, along with sediment deposition patterns. Alluvial fans and deltas are also covered, highlighting their roles in sediment deposition.

What is a key characteristic of young streams?

• Numerous meanders

• Wide floodplains

• High energy and steep slopes

• Low energy and slow flow

Which feature is commonly found in mature streams?

• Steep slopes

• Oxbow lakes

• White water rapids

• V-shaped valleys

How do mature streams primarily erode?

• Downward

• Side to side

• Upward

• Inward

What is a defining feature of old streams?

• Steep slopes

• White water rapids

• High energy

• Wide floodplains

What type of sediment is most likely to be deposited by old streams?

• Boulders

• Cobbles

• Silt and clay

• Gravel

As streams lose energy, which type of sediment is deposited first?

• Sand

• Clay

• Silt

• Boulders

What is an alluvial fan?

• A type of delta

• Deposition without rivers

• Erosion feature

• A type of river

Where do deltas typically form?

• In deserts

• At river sources

• At river mouths

• In mountains

What happens to sediment in a delta?

• It forms oxbow lakes

• It is eroded away

• It forms new land

• It dissolves in water

How do alluvial fans differ from deltas?

• Deltas are deposition without rivers

• Alluvial fans are deposition without rivers

• Deltas form in deserts

• Alluvial fans form in oceans