Upper Course Features Course Features 2015.pdf · V SHAPED VALLEY IINTERLOCKING SPURS POTHOLES...
Transcript of Upper Course Features Course Features 2015.pdf · V SHAPED VALLEY IINTERLOCKING SPURS POTHOLES...
RIVERS
The point where the river begins
A small river or stream that joins another one.
Where 2 rivers meet
The part of the river that the tide enters
The point where the river meets the sea
The whole area of land that is drained by the river and its tributaries
Drainage Basin
The high ground that separates two river systems Vocabulary of Rivers
Rivers have 3 courses or
stages
The Upper Course or Youthful Stage
The Middle Course or Mature Stage
The Lower Course or Old Age Stage.
Youthful Stage – the river flows very fast up in the mountains – it is only a small stream here. The river has steep sides and a narrow valley
Mature Stage – the river begins to flow in the lowlands – the valley has a wide floor and gentle sides
The Old Age Stage – the floor of the river valley is very flat. It flows towards the sea.
RIVERS AS THEY FLOW, WEAR
AWAY THE ROCKS ON THEIR BEDS
AND BANKS.
THEY TRANSPORT THIS
MATERIAL – CALLED ITS LOAD
THEY DEPOSIT THEIR LOAD
ALONG THE WAY.
RIVERS ERODE IN FOUR WAYS
THE FORCE OF THE WATER WEARS AWAY THE
ROCK – HYDRAULIC ACTION
ROCKS CARRIED IN THE RIVER’S WATER
WEAR AWAY THE BED AND THE BANK OF
THE RIVER – ABRASION
THE PEBBLES IN THE RIVER WATER BOUNCE
OFF EACH OTHER AND ARE ROUNDED -
ATTRITION
MINERALS IN THE WATER DISSOLVE SOME
ROCKS SUCH AS LIMESTONE – SOLUTION
How rivers transport their load
THE YOUTHFUL STAGE OF
A RIVER
THE UPPER COURSE OF A RIVER CONTAINS
THE FOLLOWING FEATURES
V SHAPED VALLEY
IINTERLOCKING SPURS
POTHOLES
RAPIDS
WATERFALLS
V SHAPED VALLEYS ARE ALWAYS FOUND HIGH UP IN THE MOUNTAINS WHERE THE STREAM IS BEGINNING TO FLOW.
FREEZE THAW ACTION ALSO WEARS
AWAY THE ROCKS ON THE VALLEY SIDES
V shaped valley and interlocking spurs
Waterfalls
Angel Falls,
Venezuela,
plunge
979m onto
lowland in
valley
Niagara
Falls,
Canada
Iguacu Falls, South America
Canada
The pebbles swirled around by the
water as it flows along its course.
The pebbles act like a drill in the bed
of the river and drill holes into it.
These holes are called POTHOLES.
They can join together over time so
that the bed of the river is deepened.