Water on the land

The river valley
1. Upper course
  1. STEEP GRADIENT
  2. V-SHAPED VALLEY
  3. SHALLOW CHANNEL
3. Middle course
  1. MEDIUM GRADIENT
  2. GENTLY SLOPING VALLEY SIDES
  3. DEEPER CHANNEL
4. Lower course
  1. VERY WIDE
  2. NEARLY FLAT VALLEY
  3. DEEP CHANNEL
  4. (a pool goes from shallow to deep as with a channel)
5. REMEMBER: HIGH TO MEDIUM TO LOW (IT GOES FROM STEEP GRADIENT TO MEDIUM GRADIENT TO LOW GRADIENT
EROSION
1. VERTICAL EROSION
  1. -DEEPENS RIVER CHANNEL/VALLEY -DOMINANT IN UPPERCOURSE
  2. LATERAL = LATER COURSES VERTICAL = VERY FIRST COURSES
2. LATERAL EROSION
  1. -WIDENS CHANNEL/VALLEY -IN MIDDLE + LOWER
3. FOUR STAGES
  1. 1: HYDRAULIC ACTION
    1. 2: ABRASION
      1. 3: ATTRITION
        4: SOLUTION
        water dissolves rock : limestone + chalk
        DISSOLVE to make a SOLUTION
        rocks smash together and break, edges round off as they rub
      2. Rocks carried by river rub and wear channel away
    2. force of a water breaks rock particles away from river channel
      1. ACTION BY FORCE
  2. Harry Ate Apple Sorbet
TRANSPORTATION
1. 1: TRACTION
  1. 2: SALTATION
    1. 3: SUSPENSION
      1. 4:SOLUTION
        SOLUBLE materials dissolve in water + are carried along
      2. SMALL particles (silt + clay) carried by water
    2. pebble size particles go along river bed by force of water
  2. LARGE particles pushed along river bed by force of water
2. Tracy Saw Susan Sobbing
DEPOSITION
1. River drops eroded material
2. When a river SLOWS down
3. -LOW WATER VOLUME IN RIVER -INCREASED ERODED MATERIAL IN RIVER -RIVER REACHES ITS MOUTH
  1. WHY??
FLOODING CASE STUDIES
1. CARLISLE, ENGLAND
  1. CAUSES
    1. LARGE URBAN AREA = IMPERMEABLE MATERIALS = INCREASED RUN OFF
      1. HEAVY RAIN FALL (200mm 36hours)
  2. PRIMARY EFFECTS: -3 DEATHS -RIVERS POLLUTED WITH RUBBISH + SEWAGE
    1. SECONDARY EFFECTS: -3000 JOBS AT RISK
      1. LONG TERM RESPONSE: HOUSES ON STILTS
        SHORT TERM RESPONSE: CHARITIES GIVE FOOD
  3. RIVER EDEN
2. SOUTH ASIA, BANGLADESH + INDIA
  1. CAUSES
    1. MELTING SNOW FROM GLACIERS HIMALAYEN MOUNTAINS
      1. INCREASED DISCHARGE OF BRAHMAPUTRA
      2. PEAK DISCHARGE OF BRAHMAPUTRA + GANGES REACHED AT SAME TIME
        MORE DISCHARGE DOWN STREAM
  2. PRIMARY EFFECTS: -2000 DEATHS -RIVERS POLLUTED WITH RUBBISH + SEWAGE
    1. SECONDARY EFFECTS: -4000 SCHOOLS AFFECTED
      1. LONG TERM RESPONSE: FLOOD DEFENCE SCHEME
        SHORT TERM RESPONSE: EVACUATION
  3. BRAHMAPUTRA + GANGES

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	Creado por ellierosedyson hace alrededor de 10 años