This topic contains a solution. Click here to go to the answer

Author Question: Define and describe the formation of an alluvial fan. How does it differ from a delta? What will ... (Read 42 times)

TFauchery

  • Hero Member
  • *****
  • Posts: 500
Define and describe the formation of an alluvial fan. How does it differ from a delta?
 
  What will be an ideal response?

Question 2

Define base level. What processes cause base level to change?
 
  What will be an ideal response?



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

ndhahbi

  • Sr. Member
  • ****
  • Posts: 390
Answer to Question 1

When a stream flows out of a narrow bedrock channel in a mountain range, it forms a fan-shaped mass of alluvium called an alluvial fan because the water enters a broad valley where there are no hard-rock valley walls to confine the flow. Alluvial fans form when the discharge of the stream does not change, but the flow is deeper in the upstream channel than it is where the water spreads out downstream as a shallow sheet. The shallower flow exerts less shear stress, and this means the stream power drops, so sediment abruptly deposits to form the fan. A delta is the landform produced by deposition of sediment where a stream enters a lake, reservoir, or sea. Deltas form when there is a drop in stream velocity as it reaches the standing body of water and this causes a drop in stream power which leads to deposition.

Answer to Question 2

The point at which a stream is no longer eroding or depositing sediment. Streams seek to erode to this point. Ultimate base level is sea level. Base level can change when the system changes. Sea level can impact baseline such that when sea level falls, base level falls and the stream must adjust to the new lower shoreline through incision. During sea- level rise, the stream adjusts to a higher shoreline position with deposition occurring in the lower part of the stream.




TFauchery

  • Member
  • Posts: 500
Reply 2 on: Jul 16, 2018
Excellent


elyse44

  • Member
  • Posts: 319
Reply 3 on: Yesterday
Wow, this really help

 

Did you know?

Hypertension is a silent killer because it is deadly and has no significant early symptoms. The danger from hypertension is the extra load on the heart, which can lead to hypertensive heart disease and kidney damage. This occurs without any major symptoms until the high blood pressure becomes extreme. Regular blood pressure checks are an important method of catching hypertension before it can kill you.

Did you know?

The most common treatment options for addiction include psychotherapy, support groups, and individual counseling.

Did you know?

The average human gut is home to perhaps 500 to 1,000 different species of bacteria.

Did you know?

As of mid-2016, 18.2 million people were receiving advanced retroviral therapy (ART) worldwide. This represents between 43–50% of the 34–39.8 million people living with HIV.

Did you know?

The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.

For a complete list of videos, visit our video library