Mississippi Delta Flashcards

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1
Q

Background Info

A

3rd longest river system in world

Width ranges from 6 metres to 17700 metres

31 states and 2 Canadian Provinces

Sediment: 40% silt, 30% clay, 30% fine sand

Birds foot delta

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2
Q

Formation

A

Delta cycle:

New delta lobe is created over 1000 years

Occurs bc of sediment transported from upper and middle to lower course and deposited at mouth

Plants grow at sediment and transform into thriving plant community

Lobe continues to grow up river path, eventually cuts course to make a shorter route, starts process again

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3
Q

How was the delta formed?

A

Formed 7500 years ago when sea levels rose

New delta formed 5500 yeas ago when sea levels dropped

St. Bernard Delta formed 4000 years ago when river broke away and relocated

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4
Q

Features on Delta

A

Huge amounts of sediment deposited

Interconnected habitats including salt marshes

Under threat due to human construction of canals, dams, channels etc.. to make trade easier

Humans drained wetland for urban development

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5
Q

Beaches on the Delta

A

No different to beaches on coasts
Formed via deposition and transportation of sediment

Long shore drift occurs, more frequent changes in direction

Made of fine sand, easily eroded, vulnerable to stormy conditions

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6
Q

Inter related features

A

If one feature is eroded, others will be (sediment budget increases -> beaches grow)

Delta environment forms through deposition of material bc of lower course of river causing sediment to be dropped

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7
Q

Characteristics

A

Present Day Lobe: Balize Delta

Lots of tributaries

High altitude

Steel mountains

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