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Why a large river like Congo not have delta?
The river Congo has a large load but a high velocity near its mouth which enables most of its load to be carried far out to sea, there by preventing the formation of delta.
River Niger also has a large load but its velocity near its mouth is low. Much of its load is deposited in its mouth where an extensive delta has formed
Value of Rivers / Economic importance of Rivers
  1. Water supply for both domestic use, industrial uses, industrial uses and for irrigation purposes example
  2. Rivers are used for local transport (Navigation) they provide inland ports on their courses E.g. St Louis on River Mississippi in U.S.A.
  3. Provide sites for hydro-electric power generation. Harnessing of hydro-electric power is common all over the world. E.g. Mtera dam in Tanzania, Seven forks dams on river Tana in Kenya.
  4. Rivers are sources of building materials. Sand for building is scooped from the river beds and valleys like in Machakos in Kenya.
  5. Rivers also form sources of various alluvial minerals like gold and diamonds e.g. alluvial diamonds are mineral along the course of R. Orange in S.A and Namibia.
  6. River deposit alluvial soils a long their valleys during floods and at their deltas. These alluvial soils are fertile and hence for agriculture e.g. along the Nile valley and its delta in Egypt.
  7. Rivers have features, which provide tourist attractions such features are like waterfalls and gorges e.g. Victoria falls.
  8. Rivers provide rich fishing grounds e.g. R Nile, R Tanah, River Nguruka.
  9. Rivers form natural boundaries between communities, districts, provinces and countries e.g. Kagera river between Tanzania, Uganda, Rwanda.
DRAINAGE PATTERNS
-Removal of water from the surface
-Drainage pattern is the actual arrangement or layout of its tributaries over the surface.
Factors which influence drainage patterns
  1. Slope –:
This will determine the direction and speed of flow the steeper the flow the higher the speed and vice versa.
  1. The function of structure- :
Uniformity whether the rocks have the joints or uniform rock e.g. granite will be different from limestone which has joints.(rock with joints will cause the drainage pattern to follow the lines of weakness but uniformity rocks, the slope is the one which will determine the drainage system.).
  1. Nature of rock- :
hard and soft rock .Drainage pattern develop of the soft rock because it is easy for water to penetrate unlike on hard rock, drainage pattern becomes diff to develop Alternating layers, having soft sand hard rock, the drainage pattern will develop on the soft rocks only.
Types of Drainage Patterns
  1. Dendrites- This pattern has a shape like the trunk and branches of a tree without leaves. The tributaries join one another at a low angle (less than 90) from many directions.
-Develops where there is no structural control because such pattern develops in a uniform rock, the slope is the only factor which in thence‟s the drainage pattern. Example Granite.
DENDRITIC PATTERN
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    1. Trellis –Pattern develops in a region which is made up of alternate belts of hard and soft rock.
-Shape is rectilinear or almost rectangular in shape
-Tributaries join one another and eventually join the main river at a right angle (900)
-Major control is the rock structure and nature of rock with joints or alternating layers of rocks.
-This drainage pattern gives rise to various types of rivers (stream)
(s) Sub Sequent River – Is any tributary which joins the consequent stream at a right angle.
(c) Consequent river – This is the main river which flows down slope.
TRELLIS:
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(o) Consequent stream – Any stream which flows in the opposite direction to the consequent stream and join the subsequent stream. Almost right angle.
(MC) Minor Consequent river– A stream which flows parallel to the consequent stream and joins the subsequent stream.
  1. Radial – Shape is like a spokes of a wheel. (Bicycle wheel) that radiates from the centre which can be a conical hill (volcano) ->Develops on a volcano. The major control is the slope. E.g. Granite, volcanic rocks, basalts.
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  1. Centripetal- Streams from various directions converge to the center. Common in inter – mountain basins or basins between highlands .Major control is slope.
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  1. Annular – A pattern with streams often joining at sharp angles, but arranged in a series of curves about a dissected dome, basin or crater area. Major control is the nature of the rock.
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  1. Accordant and discordant
    1. Accordant –This is a normal drainage system of the river. In this drainage system, the river flows in accordance with the rock structure and slope. It follows the line of weakness hence hence revealing the relationship with rock structure and slope. This is described as being accordant.
    2. Discordant – Drainage systems that are opposed to the dominant structure.(rock structure, slope and land forming processes.
  2. Superimposed – Some rivers have developed a drainage pattern which is in no way related to the
structure of the region in which it occurs. The drainage pattern discordant to the structure of the land surface in which it occurs.
-Doesn‟t have any relationship with geological structure. It has forced itself to be in a place
STAGES IN THE FORMATION OF A SUPERIMPOSED DRAINAGE PATTERN
  1. Original folded surface.
  2. Region is reduced to a plain due to erosion
  3. Subsidence results in region being buried by new rocks but subsequent uplift sees the formation of a drainage pattern. The main river is draining at right angles to the axis of the original structure.
  4. Tributaries to the main river develop wide valleys in the weaker rocks as the main river erodes vertically it cuts across the ridges of strong rock and form gorges. The stronger rock forms ridges because the weak rocks are worn away and not because the region has been uplifted.
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  1. Antecedent drainage – A river pattern disturbed by earth movement (uplift or folding). A river which is capable of maintaining its course after up lift and erosion is called Antecedent. E.g. Ganges River, Snake River and River Colorado.
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RIVER CAPTURE (piracy)
It is process where one river diverse the head water of the neighboring river in its own course/valley (upper course)
Condition necessary for river capture to occur
i. The capturing stream should flow at a lower level than its victim stream (capture stream) ii. The capturing stream must be stronger and must be flowing at a steeper slope than its victim. iii. The capturing must be flowing over easily eroded rocks that are weaker rocks.
iv. River rejuvenation.
Processes:
  1. Two stream which are adjacent
There is head ward erosion which makes S extend head ward to C2
    1. After years of erosion C2 is diverse to C1 where all its water enters C1.
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Evidence /feature related to river capture.
  1. Elbow of capture.
Is a point where there is a sharp turn of the river. Is the sharp change in the direction of the river course at the point of capture.
    1. Wind gap (dry valley).
This is a gap between elbow of capture and beheaded stream which is dry. The beheaded stream will not dry because it receives water from other sources.
    1. Misfit stream (beheaded river).
A stream carries less water than the valley depth (less water and becomes too small for its valley). A river which is flowing on a valley which is wider than the size of the river.
iv. Rejuvenation.
Feature of river rejuvenation can be seen in the capturing stream.
Examples:
Great berg River capture in S.A, River Volta capture in Ghana, River Niger capture in Nigeria.
RIVER REGIME
Is the seasonal variation of the volume of the water in its channel.
FACTOR INFLUENCING RIVER REGIME.
CLIMATE
a. Precipitation is responsible for the variation of rainfall, snow melt.
  • High amount of rainfall and snow melting will increase the volume of the river.
  • River regime follows the rainfall regime.
  • During winter, volume decreases and early summer volume increases
b. High temperature, melting increase and volume increase also during high temperature, evaporation increases and reduces volume.
  • Low temperature freezing increase and volume decreases, this leads to the fluctuation of water volume.
NATURE OF THE ROCK.
Porous rocks and previous rock allow water percolation; hence much of the water sinks in the ground and reduces volume of water.
  • Impermeable rock does not allow water to sink hence, increase volume.
SLOPE.
The steeper the slope less the percolation and evaporation, hence volume is maintained. In gentle slope, more loss of water because water stays for a long time hence percolation increases and evaporation increases.
VEGETATION.
Variation matter with the area/surface the rivers flowing, the dry/bare land will have less water during dry season because of the increase in evaporation compared to the river passing throughout the forest.
  • During rainy season, the bare land will have more volume because there is nothing which will retain the water but the river which passes through the forest, the vegetation retains the water.
NUMBER OF TRIBUTARIES JOINING THE RIVER.
The larger the number of tributaries, the larger the volume and vice versa.
HUMAN ACTIVITIES.
Taking place along the river or the river basin e.g. Irrigation, scheme, during dry seasons tends to reduce the water volume.
  • Agriculture on the river basin clears the forest whereby they reduces the water volume.(farming activities)
  • Clearing the land leads to increase in evaporation which reduce water volume.
TYPES OF RIVER REGIME.
There are three types of river regime as follows;
    1. Simple River Regime.
Is a type of River regime where there is seasonal variation of water volume such that there is one high water volume period and one period of low water volume.
  • These occur where there is one dry season and one wet season most common in the tropical regions. Example, Ruvu, Wami, Ruvuma Rivers.
    1. Double River Regime (Regime of first degree of complexity).
This is a type where there are two distinct of high water periods which maybe because of snow melt or double rainfall maxima.
  • This occurs on equatorial regions where they are two peaks of high rainfall e.g. River Congo and River Amazon in S. America.
  • The volume of the river varies according to those rainfall peaks.
    1. Complex river regime (Regime of second degree of complexity).
It‟s a type of river regime which evidenced the longest river in world with wider basins and numerous tributaries of different regimes.
  • They cut across different climates. Example River Mississippi, the river volume isn‟t much affected because it across different climates in different regions.
IMPORTANCE OF STUDYING RIVER REGIME.
All development schemes planned on the river and its valley should have proper knowledge on river regime.
Example, RUBADA – Rufiji Basin Development Project /Authority.
TVA – Tennessee Valley Authority
Kagera River Development Authority
1. NAVIGATION:
Navigation should be planned and the vehicle also should be planned according to the depth of the water.
– During high water level can use a certain vehicle and during low water level certain vehicle can be used (type and size of vehicle)
  1. CONSTRUCTION OF HYDRO-ELECTRIC POWER STATION.
Plan for the machines to be placed considering the level of water which keeps on varying. Because during low water level and the machines are placed at a upper position, the water won‟t be able to reach and the machines won‟t work.
  1. CONSTRUCTION OF BRIDGES.
The engineer has to plan before building sometimes water level increase and sometimes decrease. When water level increases, energy increases hence leads to destruction of bridges. To have effective bridges must study river regime so as to make strong bridges which can overcome high energy of the river.
  1. FLOOD CONTROL.
Must know the time that flood may occur and the level of water which will increase.
– Construction of dams will control floods but also constructing dams should consider the variation in the level of water so as to be able to prevent floods to continue taking place Eg. In U.S.A TVA builder dams to control floods.
  1. AGRICULTURE ACTIVITIES ON THE FLOOD PLAIN.
Example River Nile the consider/depend when the water level is high, irrigation is not important but during dry season, canals are constructed at the level of low water so that irrigation can take place, hence important to know the river variation.
  1. SETTLEMENT.
To establish settlement on the river basin must know the river regime, the settlement must be above the area of floods so that during high water level the settlement should not be flooded. (Areas free from floods)
Concept of graded profile
  • Consider the river long profile from source to mouth.
  • Refers to the profile of the river, which has attained a state of dynamic equilibrium, where is there is balance between the rate of erosion and the rate of deposition.
  • In its simplest interpretation, a graded river has gentle slope and long profile with the gradient decreasing towards its mouth.
  • It‟s concave in shape and smooth due to higher erosion in the middle profile of the river and less erosion at the source (great amount of materials) at the lower course, erosion is less because smaller volume of both of heavy loads and very low speed water and load.
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CRITICISMS OF THE CONCEPT OF THE GRADED RIVER PROFILE:
There are several obstacles that normally prevail along the river course, which in term distort the equilibrium that river attempts to attain includes;
-The variation in the nature of the rock on the river bed and banks of the river. Hard and soft rock that offer cliff resistance to erosion.
  • Climatic variation, for which passes cliff climatic region cannot attain the stage. Variation rainfall and areas.
  • The presences of water bodies like lakes in the river course. The lakes become the center of deposition of sediments.
  • River rejuvenation. Either sea level changes, river capture interfere with the attempt to attain equilibrium
  • Continuous erosion along the river channel can be an obstacle to the attainment of balance.
  • Vegetation that occupies certain part of a river channel.
RIVER REJUVENATION:
  • Juvenile – young/youth
  • Juvenation – process
  • Repeat /do again
River rejuvenation;
Is the process of renewal of the erosive activity of the river valley after it has reached its old stage.
After reaching its old stage instead of deposition it starts eroding.
Causes of river rejuvenation:
A. i. Eustatic change (fall in the sea level) ii. Isostatic change (land uplift and subsidence) iii. Discharge (increase in the river volume)
I. EUSTATIC CHANGE
Caused by the fall of the sea level (negative movement of base level)
The river profile will have to adjust so as to reach the new sea level.
  • The sea level has changed from L1 to L2
  • Withdraw of water from the ocean by glacial/during glacial period – fall in sea level.
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II. DIASTROPHIC CHANGE. (Isostatic).
Fall of the sea level floor relative to the land or rise of the land relative to the sea floor – this will make the river start erosion again from the upstream.
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B STATIC REJUVENATION.
i.Discharge.
Increase in the river discharge by increase in the volume of the river and can be caused by;
  1. Increase in precipitation either melting of ice or rainfall
  2. By river capture, when a weaker river is captured by the strong river the volume of the strong river will increase. This will make the river to start erosion again and will leave some marks /feature in the river valley.
FEATURES/LANDFORMS RESULTING FROM RIVER REJUVENATION i. Knick point.
This is a point of a river valley where there is a sharp break of a slope as a old base level joins the new base level after river rejuvenation has occurred.
Note.
  • If a gradual fall – gentle slope will cause rapid.
  1. Waterfall /rapid.
Where there is a knick point with a sharp break forms a water fall for the river to join the new base level e.g. Along the river Congo there is a knick point at old base level Bathurst fall. EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
  1. River terraces.(Paired)
Occur on the flooded area. There are the steps or benches on either side of the river valley formed as a result of undercutting of the river due to renewed erosion.
  • If a river on a flood plain is rejuvenated, the down cutting of the river will produce terraces with equal size.
  • – If the process of river occurs several times a series of terrace will occur.
  • -Down cutting is vertical erosion, the volume of the river is the same. This will deepen the river.
  • -Leaves deposition on the terraces.
  • -The knick point keeps migrating up stream.
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iv. Incised meanders (incise – cut down).
These are the curved bend of the river valley that has been incised into the land‟s surface so that the rivers now wind between steep valley walls.
Two types of meanders
Ingrown meanders – Asymmetrical (the valley is not uniform; one part of the valley is much undercut.)
  • Occur due to resistant rocks which do not erode fast compared to the other side (concave side) which erosion takes place at a high rate.
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Entrenched meander.
Is a steep sided symmetrical meander with side standing vertically and parallel to each other. This is produced by vertical erosion on rocks with almost uniform resistance.
  • There is fast erosion.
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3) v. Valley within a valley
  • It is a deep step sided valley within the former valley of river. When the rejuvenation is fairly rapid to cause large fall of the base level producing steep sided valley.
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WIND
Is air in motion or is the movement of air from the region of high pressure to region of low pressure
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
They are residual hills consisted of land and resistant rock left standing on the surface often the rest part of the earth has been eroded.
  • When inselbergs are smooth they are called boarnads.
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  • They are characterized by a lot of joints.
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6.DESERT PAVEMENTS.
These are the horizontal areas of bare, polished rock formed by the scoring action of grains of quarts. – Flatter in shape (escarpment)
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7.VENTIFACT (DRAIKANTER).
These are heavier rock blocks pebbles left behind after wind has sorted and carried away all materials.
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FEATURES DUE TO WIND (AEOLIAN) DEPOSITION.
The materials transported by the wind form different feature after deposition.
  • Features formed are like dunes (bar khans and seifs), loess and ripples.
1. SAND DUNES.
Hills of sand deposited by wind in the desert. Influenced by the extent of vegetation cover, the size of sand particles, amount of the materials and the velocity of the cover
  1. Barchans/bar khans.
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
Crescent – shaped and lying at right angle to the prevailing wind horns pointing downwards
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3) Eddies (an abrasion process) type of wind.
    1. Seif dunes.
(Seif dunes) they are sometimes called longitudinal dunes. They are long narrow ridges of sand which lie parallel to the direction of the wind. They occur in the small scale in sand
areas
    1. LOESS.
Is an accumulation of sand that has been carried and deposited beyond the desert limits. Loess leads to the formation of fertile soil. Example can be found in China. EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
    1. RIPPLES.
They are the smallest wave structure, sometimes less than centimeter high. They are commonly found between dunes.
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  1. Why are desert found in the western part of the continents?
  2. Desert on the western side of continents are there because cold currents exist off the western side continents. Winds blowing over these currents lose their moisture over the sea and are dry by the time they get to land.
  3. Due to prevailing winds. And that both continents have high mountain ranges on the west side. Air coming from the mountains (causing the moisture to condense out) and that leaves a rain shadow on the eastern side.
  4. Due to their location, first being in the sub tropics places them in an area prone to lots of high pressure year round. High pressure discourages cloud development and precipitation being on the western of the continent, blocks humid air masses from reaching them.
GLACIATIONS
It appears that roughly every 200 – 250 million years in the earth‟s history, there have been major periods of ice activity. Of these the most common (recent) and significant occurred during the Pleistocene period of the quaternary area.
In the two million years since the onset of the quaternary, there have been fluctuation in goods temperature of between 50C which have led to cold phases (glaciers) and warm phases (inter glaciers)
CAUSES OF ICE AGE/ THEORIES
-Variation in support activity may increase or decrease the radiation coming on earth.
-Injection of volcanic dust into the atmosphere can reflect and absorb radiation from the sun changes in atmospheric carbon dioxide gas could concentrate the green house effects (absence of carbon dioxide. -The movements of Planets either into colder latitudes or at constructive margins where there is an increase in altitude could lead to an overall drop in world land temperature (high latitude low isolation.
-Changes in ocean currents or jet streams.
-Changes in atmospheric carbon dioxide gas could concentra
te the green house effect
SNOW ACCUMULATION AND ICE FORMATION:
-As the climate gets colder more precipitation is likely to be in the form of snow in the winter and there is less time for that snow to melt in the shorter summer.
-If the climate continuous to deteriorate, snow will be falling throughout the year forming a permanent snowline.
(The level above which snow will lie throughout the year).
-In the northern hemisphere the snow line is at a lower altitude on north facing slope and these receive less isolation (sun rays) than south facing slopes.
-Where snow collect in hollows it becomes compressed by weight of subsequent falls and gradually developed into more compact, dense form called firm or nerve.
.Firm is compacted snow which has experienced one winter freezing and survived for summer‟s melting. -It is composed of randomly oriented ice crystals separated by air passed.
-In the temperature latitudes such as in the Alps, summer melt water percolates into the firn only to freeze either at night or during the following winter forming an increasing dense mass.
-Air is progressively squeezed out and after 20-40 years the firm will have turned into solid ice.
-This same process may take several hundreds of years in Antarctica and Greenland where there is no summer melting.
-Once has formed it may begin to flow downhill under the force of gravity as glacier.
GLACIER AN ICE MASSES:
-Glaciers may be classified according to size and shape characteristic which are relatively easily to identify by field observation. These are,
LANDFORMS PRODUCED BY GLACIAL EROSION.
1.Niche glaciers.
-Very small and occupy hollows and gulley on north facing slopes in the northern hemisphere 2. Corrie or cirque.(highland glacial erosion features.
-Although larger than niche glaciers are smaller masses of ice occupying arm – chair shaped hollows in mountains.
They often over pill from their hollows to
feed valley glaciers.
-These are armchair – shaped hollows with a steep back wall and a rock basin. They are known as corries in
Scotland.
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3.Arêtes.(highland glacial erosion features)
-When two adjacent cirque erode backward or sideways toward each other the previously rounded landscape is Transformed into a narrow, rock steep side ridges called an arête, example Alps in Switzerland.
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4.Pyramidal peak.
-If there are three or more cirques all side of a mountain a pyramidal peak or horn may be formed.
-This feature has steep side and several arête radiating from the central peaks. -When either cirque is combined together can form pyramidal peak.
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  1. Truncated spurs
-Formed by meanders in the low lands, where by the rate of erosion has decreased and the rocks are hard and at the end form alluvial fans.
-Spurs whose ends have planed off due to erosion on the process of straightening the valley as it moves down the valley (highland glacial erosion feature).
  1. Crag and tail (lowland glacier erosion features)
-This consists of a larger mass of resistant rock or crag (e.g. Basaltic rock crag upon which Eden burgh has been built).
-High pressure where is small area and low pressure is large area.
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  1. Roche mountaineer. (Lowland glacier erosion feature)
-An outcrop of resistant rock which rise above the plain smoothed by ice on the upstream by abrasion and plucking processes. This feature also occurs in glaciated highlands. An outcrop of resistant rock smoothed by a glacier on the upstream side into a gentle slope. On the downstream side the glacier erodes by plucking to give steep and jagged (rugged) slope (lee).
Example: Mobuku Valley in the Ruwenzori mountains,Yosemite National Park in California,on the slope south of Mawaza along Mt.Kilimanjaro.
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  1. U-shaped valley/glacial trough. (Highland erosion features)
-It is a steeply sided flat-bottomed wide glacial valley. Develop from a river valley in which glacier had covered. Some contain features formed by both glacial erosion and deposition.
– At initial stage the valley occupied the V- shaped valley but because of continuous glacier erosive activities. The valley was more enlarged by being more deepened and widened becoming more opened and known as U-shaped valley.
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9. Hanging valley.
-It is a tributary valley that ends abruptly above the floor of a U-shaped valley and separated from it by almost a vertical slope.
-The rate of erosion is much greater at the main glacier valley than on the tributary valley, after glacier have retreated the floor of the main glacier valley lies far below than the floor of a tributary valley making the tributary valley to hang by ending a abruptly above the valley.
-A river occupying a hanging valley will fall more abruptly into the main valley to form waterfalls and produce alluvial fans.
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10. Rock basin (highland erosion features)
  • It is an irregular depression of the floor of glacial valley formed by unequal glacier upon the bedrock.
  • This develops when weight and thickness of glaciers increase after two glacial have joined together.
  • After glacier melts, rock basin becomes the site of lake. These are known as rock basin lakes.
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11. Ribbon lake (Finger Lake or Trough Lake).
– Is a lake that occupies an elongated trough or hollow excavated by ice on the floor of a u-shaped valley E.g. lake Michelson near Mt. Kenya (Highland erosion features)
12. Fiord. (Highland erosion feature)
  • It is a long, narrow, deep in let depression steeply sided into the sea. Fiords were formed when glaciers make the way to the sea.
  • Most of the fiords occupied by deep sea water after the coastal land submerge due to ice melting forming natural harbours e.g. the also fiord of Norway.
13. Ice eroded plain. (Lowland glacier erosion)
– It is an extensive and almost level lowland area of bare rocks .It was once covered by an ice sheet which smoothed the topography and produced large area of bare rocks.
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GLACIER TRANSPORTATION AND DEPOSITION
Glacier movement can also result into the formation of depositional features such as;
1) Moraines. (Highland (alpine) deposition features) unsorted materials.
Are the unsorted fragments of different size and shape that have been eroded, transported by glacier and then deposited in ridges within the glacial valley.
Types of moraines based on area within the glacier valleys where materials have been deposited;
  1. a) Ground moraines – Formed at the bottom of glacier valley.
  2. b) Medial moraines– Formed at the point where two glacial valleys meet
Adjacent lateral moraines joined and are carried as a single long ridge of till.
  1. c) Lateral moraine – Formed along side of the glacial valley. (Ridge like piles of till along the sides of glacier).
  2. d) Terminal moraine– Occurs at the end of glacial valley as the materials had been accumulated.
    • Terminal moraines are built up when glacier is stationary.
    • Materials of terminal moraines can be carried down the valley by melt water and deposited to form a feature known as outwash plain.
  3. e) Recessional moraines – The end moraines built while the glacier is retreating. (A series of roughly parallel terminal moraines that make the step by step retreat of the glacier).
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
    1. Boulder clay plain. (Lowland glacial deposition)
(Till plain)- Is an extensive lowland (plain) area consisting of clays and boulders deposited randomly by ice sheet and burying vast area of land.
    1. Erratics are large boulders made of rock, different from that of the region where they are deposited
    2. Drumlins (unsorted materials) (lowland glacier)
They are elongated oval shaped hill that are made of clay and boulders as they were deposited irregular on a till plain (boulder plain). They occur in groups and aligned in one another.
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
    1. Eskers (lowland) (sorted fluvial – glacial material)
  • Long, steep sided ridge of course sands and gravels.
  • Formed when ice remain stationary for long time. Streams form permanent sub glacial in which materials consolidate and compact if ice melts the materials are left as ridges which referred to eskers.
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
6) Kames (lowland)
  • Is an irregular mound or hill (mass) of stratified materials (sand and gravel)
  • Kames vary greatly in shape and size and occur in isolation or large groups. They form as ice deposited materials randomly.
7) Out wash plain (lowland) EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
  • It is a wide gently sloping low lying land of gravel and sand at the end of an ice-sheet.
  • Out wash plain is usually found after boulder clay plain.
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
Value/importance/significance of glaciated land escapes to human being.
  1. Some glaciated landscape like that of boulder clay plain and others are good for agriculture.(fertile)e.g. Dairy belt in U.S.A also crop cultivation in old glacier lakes e.g. wheat cultivation in Canadian prairies.
  2. Hanging valleys are suitable for HEP generation. E.g. Norway, Sweden and Switzerland produce great proportional of hydro electricity by utilizing waterfalls of hanging valleys.
  3. Glaciated landscapes provide attractive scenery also the glaciated highlands and peaks e.g. Mt Kenya and Kilimanjaro attract tourists.
  4. Many glaciated valleys are used as grazing land as they contain good pastures. They are used for animal grazing main in summer season .e.g. In the Alps in Europe.
  5. Fiords form natural harbors e.g. Oslo ford in Norway and also fishing-grounds.
  6. Glaciated landscape contains a number of lakes which are used for navigation e.g. great lakes in N. America. 7. Melting of glaciers give rise to rivers. The rivers can be utilized for domestic and industrial purposes.
Disadvantages of glaciated landscape
1.The boulder clay plain in some reg
ions, have produced a mainly landscape which have little or no value to agriculture e.g. central Ireland.
2.Many out wash plains contain infertile sands which give rise to extensive areas of waste land.
WAVE
WAVE ACTION AND THE FEATURES IT PRODUCES.
-Is the horizontal movement of ocean water, in the movement process it does the following three main works: These are:-erosion, transportation and deposition
-Waves should not be confused with tides which are the vertical movement of sea water.
MOVEMENT ASSOCIATED WITH WAVES.
1> Swash:
-The movement of sea water towards the beach is known as swash.
2> Back wash:
-The movement of water from the beach back to the ocean after the breaking waves.
3> Wave break
-Is the split of the wave when it releases its energy on the coast.
4> Wave erosion
– This takes place along shore (coast). It is determined by the nature of the rock and strength of the waves.
WAVE EROSION PROCESSES CAN BE DIVIDED AS FOLLOWS: i. Corrosive action:
-These kinds of erosion taking place when the rock fragments (particles) carried the waves are used as tools of erosion. They usually bang and cut the bare of the cliffs
  1. Hydraulic action:
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)
EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)


EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)

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1 Comment

  • EcoleBooks | GEOGRAPHY As LEVEL(FORM FIVE) NOTES THE DYNAMIC-EARTH AND CONSEQUENCE (3)

    Doctor Stuart, May 1, 2024 @ 5:01 pm Reply

    To get more notes in geography

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