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KCSE-Geography
    • formed through lava flows
    • formed due to ejection of volcanic materials/volcanic ejecta
  • This is the state/condition of the atmosphere of a given place at a given time or over a short period of time

    • Faulting is the cracking or fracturing of the rocks of the earth's crust due to earth movement while folding is the bending of the rocks of the earth's crust due to earth movement
    • simple symmetric fold
    • assymetric fold
    • overfold
    • isoclinal fold
    • Recumbent fold
    • Nape or overthrust fold
    • Anticlinorium and synclinorium complex
  • (i) tectonic plates move toward each other

    • fold mountains
    • ocean trench

    ii) tectonic plates move away from each other

    • mid ocean ridges
    • faults
    • Changes in the position of the midday sun at different times of the year
    • Variation in the length of day and night at different times of the year.
    • Causes seasons
    • Causes lunar eclipse
    • painted white to reflect heat and light
    • is made of wood because wood is a poor conductor of heat
    • it has louvres to allow free circulation of heat
    • It has metallic legs/stand to prevent termites from destroying the wood
    • It is raised about 1.2 metres above the ground to prevent terrestrial radiation
  • (i) Canada - Praires

    (ii) Russia - Steppes

    • The area has scanty vegetation because of low rainfall
    • The high temperatures/ high rate of evaporation leave the ground dry leading to scanty vegetation
    • The long periods of drought causes seeds to remain dormant state only to germinate during short rains
  • Aridity refers to the state of land being deficient in moisture leading to scanty vegetation or lack of vegetation completely while desertification is the slow and steady encroachment of large areas of barren land covered with sand onto formerly productive agricultural land

    • Deforestation leads to severe soil erosion / interferes with hydrological cycle and arid conditions set in
    • Setting up of irrigation schemes and reclamation of swampland has led to the lowering of the water table level causing arid conditions to set in
    • Poor irrigation practices can lead to soil salinisation which would not eventually support plant life
    • Poor agricultural practices such as over cultivation, monoculture , shifting cultivation, ploughing up and down  the slope all lead to soil degeneration
  • The Contraction Theory

    After the formation, the earth's surface rocks cooled faster than those of the interior. As the interior continued to cool the surface rocks wrinkled to fit on the contracting interior leading to fold mountains

    The Convection Theory

    Convectional currents within the molten rock in the mantle move in circular motion towards the crust. These currents exert a frictional drag with the sima rocks causing crustal rocks to move horizontally resulting into the formation of fold mountains

    Plate Tectonics Theory

    When an oceanic plate meets a continental plate, the dense oceanic plate sinks beneath the higher continental one. The lighter continental plate due to compression crumbles to form fold mountains

    • Environment is the external conditions that surround an organism
    • Conditions that influence the behaviour and development of an organism
    • Climatology
    • Biogeography
    • Geomorphology
    • Hydrology
    • Pedology
    •  
    • They are made up of frozen gases/dust/small rocky particles
    • They have a head and tail
    • They move along oval-shaped orbit
    • They cross orbits followed by planets
    • The gradual emergence of a ship approaching the shore
    • The earth is a planet and all planets are spheres
    • During the lunar eclipse, the spherical shadow of the earth is cast on the moon
    • Photographs taken from satellite clearly shows that the earth is spherical
    • The earth's horizon appear curved/circular when viewed from a very point
    • The difference in times at which the sun sets and rises in different parts of the world
    • Circumnavigation along a straight path leads to starting from the opposite direction
    • Extrusive igneous rocks/Volcanic/hypabyssal
    • Intrusive igneous rock/Plutonic
    • Rocks weather down to form soil that supports agriculture
    • Some rock features are tourist attraction
    • Some rocks provide materials for building construction
    • Some rocks are source of salt
    • Some rocks provide raw materials for manufacturing industries
  • Month

    J

    F

    M

    A

    M

    J

    J

    A

    S

    O

    N

    D

    Temperature (0c)

    21

    21

    20

    18

    15

    14

    13

    13

    15

    16

    18

    20

    Rainfall(mm)

    24

    25

    30

    74

    17

    143

    131

    126

    70

    55

    31

    27

    (a) (i) What is the mean annual range of temperature

            (21-13) = 8 degrees celsius

        (ii) Calculate the rainfall total for town Y

            753mm

     (b) state three climatic conditions experienced in the hot deserts

    • Low rainfall below 250 mm per year
    • High temperatures throughout the year
    • The diurnal range of temperatures is very high/ Hot days and cold nights
    • Low humidity
    • The skies are cloudless
    • There are strong dusty winds/sand storms
    • An ocean is a large/extensive body of saline water occupying a basin between continents while a sea a large body of saline water along the continental margins
  • It is the process through which solid, gaseous and solid materials are forced into the earth's crust or onto the surface of the earth due to high pressure and temperature

  • Lava Plateau

    • It is formed when magma reaches the earth's surface through multiple vents/fissures
    • The lava is ultrabasic/ extremely fluid
    • The lava flows over long distances evenly covering hills and depressions
    • The lava cools slowly and solidifies
    • successive eruptions lead to more and more layers building up forming a lava plateau

    Caldera

    • lava pours out of a central vent to form a volcanic cone
    • The vent is sealed when lava solidifies in it
    • The solidified lava blocks gases and steam beneath preventing them from escaping
    • Pressure piles up below the lava
    • The pressure leads to a violent eruption which blows off the top of the cone forming a depression
    • The depression is large and circular and it is known as a caldera

    Geyser

    • Water percolates underground through cracks in the round
    • The water gets in contact with hot igneous rocks
    • The water is superheated to form gases/steam
    • Pressure builds up
    • pressure forces steam and water to be ejected to the surface
    • The water and steam is emitted intermittently as pressures level changes to form a geyser

     

     

  • What is a mineral ore?

    • A rock bearing a valuable mineral within the crust of the earth

    state three formations in which mineral ores occur in the earth's crust

    • Veins
    • seams and beds
    • Alluvial deposits
    • Weathered rock products

    What is cottage industry?

    • This is a small industry usually in the rural areas and which uses local raw materials and require little capital to start and operate

    Identify two areas in Kenya where wind energy is harnessed

    • Northern Kenya
    • Ngong Hills
    • Coastal region
    • Some parts of Nyanza

    Give three advantages of wind energy

    • Inexhaustible
    • Available as long as wind blows
    • It is cheap
    • It is clean/ Non-pollutant
    • Can be produced on a small scale
    • Supplements other sources of energy
    • Land between the wind mills can be used for other purposes
    1. a) What is human geography.                                                                                          (2mks)
    • It is a branch of geography that deals with peoples’s activities on the earth surface.

    b) State three importance of studying geography.                                                      (3mks)

    • It helps develop mental skills.
    • It enables leaners understand, appreciate different environmental influences.
    • It encourages international awareness/cooperation.
    • It helps learners appreciate important social values such as tire management responsibility.
    • It promotes positive attitude towards protection/conservation of reasources.
    • It leads to development of carrier opportunities.
    • It enables learners to explain the origin, founding of the earth/landforms.
    1. a) List two methods of underground mining.                                                               (2mks)
    • Drilling mining
    • Deep/shaft mining
    • Adit /drift mining
    • Solution mining

    b) State three ways in which minerals occur.                                                               (3mks)

    • Minerals may occur in veins and lodes.
    • Minerals may occur in seams and beds.
    • Minerals may occur as weathering product.
    • Minerals may occur as placer/alluvial deposits.
    1. a) Distinguish between fishing and fisheries.                                                                (2mks)
    • Fishing is the exploitation of water resources/Aquatic animals while Fisheries are the water bodies that contain fish and other related resources that merit fishing.

    b) List three traditional methods of fishing.                                                                 (3mks)

    • Harpooning
    • Use of herbs
    • Use of barriers
    • Basket method
    • Use of hook and line
    • Use of camp and nets
    • Use of gill nets 
    1. a) Give two social factors influencing agriculture.                                                    (2mks)
    • Religious Beliefs
    • Culture/Tradition methods
    • Land tenure system 

    b) State three characteristics of shifting cultivation.                                                 (3mks)

    • Vegetation is cleared by slashing and burry
    • There is little use of or no manure
    • The land is communally owned
    • It is mainly for subsistence
    • Plots are small and scattered
    • Farmers use simple tools
    • Farming mainly depends on family labour
    • Yields decline after a certain period of continuous use.
    1. a) What is a polder?                                                                                                           (2mks)
    • It refers to land reclaimed from sea in Netherlands.

    b) Name three polders in Netherland.                                                                            (3mks)

    • Makawaata
    • Southern Flavoland
    • Eastern Flavoland
    • North East polder
    • Wieringermeer/ Wieringer

     

    SECTION B

    1. Study the photograph below and answer questions below:

    Description: scan 005_0

  • G L A C I A T I O N
    Introduction
    Glaciation: - is the action of moving ice on the surface of the earth. It involves erosion,
    deposition and transportation. i.e. the process by which landscape is sculptured by the
    action of moving ice
    Ice: - refers to solid water formed by freezing and condensation of atmospheric water
    vapour
    Snow: - are falling pellets of frozen water from the atmosphere
    Glacier: - is a mass of ice of limited width moving outwards from an area of accumulation
    Ice sheet: - is a large and continuous mass of ice that covers a large area of a lowland
    Ice cap: - is a permanent cover of ice on earth’s surface covering smaller sections of land
    Ice berg: - permanent floating ice in large water bodies e.g. oceans
    Movement of Ice
    Ice moves outwards from its area of accumulation through the following processes: -
    a. Basal slip
    b. Extrusion flow
    c. Plastic flowage
    a. Basal slip
    The weight of ice causes the ice layer in contact with the rocks beneath to melt slightly.
    This creates a film of water which acts as a lubricant between the ice and rock surfaces.
    The force of gravity then causes the ice to slip and slide over the underlying rock.
    b. Extrusion flow
    When ice accumulates, it builds up to great thickness at the centre.
    The resultant weight compresses the layers of ice beneath forcing them to spread out
    where there is less pressure.2
    c. Plastic flowage
    Within a mass of ice, great pressure is exerted on the layers at the bottom, sides and
    centre.
    This pressure causes some ice particles to melt slightly thereby shift their position
    slightly downhill before refreezing
    Factors influencing the rate at which ice moves.
    i. Gradient of the land- Ice moves faster on steep slopes compared to gentle slopes due to
    the influence of the force of gravity
    ii. Thickness and weight of ice - Thick glacier moves faster as a result of own weight exerting
    pressure at the bottom. This induces slight melting hence faster movement
    iii. Friction - Movement of ice within a valley glacier is faster at the centre where friction is least
    than at the sides and at the bottom.
    iv. Season movement of ice is faster during summer because the ice thaws more frequently
    Processes of Glaciation
    This involves glacial erosion, glacial transportation and glacial deposition
    Glacial Erosion
    This involves plucking, abrasion and sapping
    (a) Plucking/Quarrying
    This occurs when ice at the base and the sides of a glacier freeze onto the rocks
    The rocks are then pulled and carried away by the moving ice
    It is common in well jointed or faulted rocks
    (b) Abrasion
    This is caused by rock debris that is embedded in a glacier.
    These debris scratch , scrape and polish the rock surfaces over which the glacier moves
    (c) Sapping
    This refers to the breaking of rocks through alternate freezing and thawing of the water
    contained in the cracks between the glacier and the floor/side of the mountain3
    Factors influencing glacial erosion
    i. Nature of the underlying rock
    Well jointed/faulted rocks are easily eroded by plucking process since the joints allow
    water to enter into the rock.
    Soft rocks are eroded faster by abrasion compared to hard/resistant rocks.
    ii. Availability of debris
    Debris acts as erosive tools. The more the debris embedded in the ice the more effective
    is abrasion process.
    iii. Speed of the glacier
    The faster the speed the greater the erosive energy.
    iv. The thickness and weight of the glacier
    A thick glacier exerts great pressure on the underlying rock causing weathering.
    The rock debris embedded in the glacier is pressed down by the thick glacier to erode by
    abrasion.
    Glacial Transportation
    Materials transported by a glacier is called moraine. It consists of a variety of materials such
    as rock fragments, sand, gravel and boulders
    Moraines are of the following types:
    a. Ground moraine: - load carried at the base or beneath a glacier
    b. Lateral moraine: - load carried along the sides of the glaciers
    c. Medial moraine: - load carried on the surface but at the centre
    d. Terminal moraine: - material deposited by the glacier at the point where it melts
    Drawing
    Glacial Deposition
    Sometimes, parts of a glacier may become so heavily ladened that its ability to transport its
    sub glacial moraine is reduced or stop, deposition then occurs
    Glacial deposits are divided fluvio-glacial and till deposits
    Fluvio glacial deposits are materials deposited by water from melting ice in a glacier
    whereas tills are moraines/materials deposited by ice on melting4
    Factors influencing glacial deposits
    a. Gradient or slope of the area: - gentle slopes allow for the accumulation of large sheets of
    ice and subsequent deposition of fluvio-glacial material (materials deposited by melt water).
    b. Stagnation of glacier: - leads to pressure being exerted at the base of the glacier which in
    turn leads to melting of the base. The melt water then carries and deposits materials
    underneath the ice.
    c. Friction between the moving ice and the rock surface leads to deposition of the heavy
    materials underneath the ice.
    d. Weight of the glacier: - heavy glaciers tend to be deposited faster/more
    e. Amount of glacial drift (till and fluvio glacial deposits). When a glacier has so much sub
    glacial moraines, it becomes too heavy forcing it to deposit some of its load.
    Resultant features of glaciation in highlands/highland areas
    i. Cirques/corries
    These are deep and wide hollows at the head of glaciated valley or high up above the
    sides of the valley
    It is formed due to interchanging processes of freeze and thaw of snow in winter and
    summer respectively
    When snow accumulates in a shallow and pre existing depression on the mountain
    side or at the head of the valley forming a glacier
    During summer, the snow melts and freezes again during winter
    Glacial abrasion deepens the hollow
    Plucking process steepens the back walls of the depression
    This actions are repeated over time to form a depression known as a cirque
    When the cirque is filled up with melt water/rain water it forms a corrie lake/tarn
    Diagrams5
    ii. Arêtes
    These are narrow sharp edged steep ridges that separates two corries/cirques
    They form when two cirques cut back to back through headward recession i.e. backward
    cutting of the walls of a cirque through plucking and nivation
    This results into very steep and sharp ridges called arêtes
    iii. Pyramidal peak
    This is a sharp and steep sided peak surrounded by cirques/corries
    It forms when cirques develop on all sides of a mountain
    Frost action (through freeze and thaw/plucking) causes blocks of rocks on the mountain
    to be broken down resulting in the back walls of the cirque to be steepened and
    deepened
    The cirques then start to cut back simultaneously and form a sharp peak called a
    pyramidal peak
    Diagram
    Examples of pyramidal peaks include Corynder and Delamere on Mt. Kenya. Also
    Albert, Margherita and Alexandria peaks on Mt. Ruwenzori
    iv. U shaped valleys/glacial trough
    These are flat and nearly flat bottomed valleys with steep sides and a U shaped cross
    sectional profile
    A pre-existing river valley is filled with ice/glacier
    As ice moves downstream, tributary glaciers increase the amount of ice in the main
    valley
    Glacier erodes the V-shaped valley by plucking and abrasion
    The interlocking spurs are trimmed into truncated spurs.
    The glacier deepens, widens and straightens the valley floor forming a U-shaped glacial
    trough
    Other erosional and depositional features formed within the glacial trough are alluvial
    fans and lateral moraines
    Diagram on long profile section of a glacial trough6
    v. Hanging valleys
    During the formation of a glacial trough, a small valley is left hanging above the major or
    over deepened valley called a hanging valley
    Initially there is a main valley and a tributary valley
    Ice fills into these valleys
    The main valley is eroded faster as it contains more ice compared to the tributary
    valleys. The floor of the main valley thus it at a much lower level than the tributary
    valleys.
    The ice melts and the tributary valleys are left at a higher level than the main valley
    They are seen to hang above the main valley as hanging valleys.
    Diagram
    Hanging valleys are common on the middle slopes of Mt. Kenya where they form
    waterfalls e.g. Vivienne falls
    vi. Fjords/fiords
    This is a submerged glacial trough on a highland coast formed after a glaciated valley is
    drowned/submerged by sea/ocean
    Action of ice through plucking and abrasion results in the widening and deepening of the
    lower sections of an already existing river valley
    With time, glacier disappears after melting leaving behind a steep sided valley.
    When there is a rise in the sea level, the straightened and deep glacial valley is
    drowned/submerged by the sea water to form fiords/fjords
    They are mainly found in temperate lands along the Scandinavian countries
    vii. Rock basin
    This is a depression within a glacial trough where differential erosion has taken place
    especially areas that have less resistant rocks.
    At the point where two glaciers converged erosion is greater resulting in the formation of
    a glacial depression called a rock basin.
    They also form in areas with less resistant rocks where the glacier removes these (less
    resistant rocks) through abrasion and plucking; leaving behind a shallow depression
    called a rock basin7
    Later, during the post glacial period, water may accumulate in the rock
    basin/depression/hollow to form lakes called finger or ribbon lakes
    Resultant features of glaciation in lowland areas
    These include both erosional and depositional features
    Erosional features
    i. Ice eroded plains
    These are extensive and almost level lowlands that were previously under ice sheets
    During glacial transportation, ground moraine erodes the rocks on the existing
    landforms through abrasion and plucking to form long and extensive plains called ice
    eroded plains
    ii. Depressions
    Lowland glacial areas may comprise of less resistant rocks that are easily eroded by
    ice sheets/glacier
    The glacier scoops out the materials from the surface through plucking and then
    lowers it to form shallow depression.
    This depression may later fill with melt water to form a glacial lake
    iii. Roche Mountonee
    This is a rock outcrop that has been eroded by the glacial processes of abrasion and
    plucking.
    Abrasion polishes and smoothens the upstream side of the rock outcrop whereas
    plucking will make the downstream end to steep and rugged
    Diagram
    They are common in mounts Kilimanjaro and Ruwenzori8
    iv. Crag and tail
    A crag is a steep-edged rocky outcrop or a hill side rock projection which protects a
    mass of less resistant/softer rock (tail) on the downstream side of the glacier from ice
    erosion.
    The crag usually lies on the path of oncoming ice; the ice moves over and around the
    crag but only slightly erodes its sides. The material that was being carried by the
    glacier is deposited on the downstream/leeward side.
    Such deposits and the softer rocks form an elongated tail
    Diagram
    Depositional features
    i. Erratics
    This is a large boulder rock which has been transported by a glacier so that it rests on a
    country rock which is different from it i.e. it has no relationship with the rock material
    found in the area of deposition
    They are deposited on the inlands when the ice melts
    ii. Boulder trains
    This is a group of erratics obtained from the same bedrock and which are deposited with
    their apex pointing to the origin of the deposited materials in a linear form
    iii. Tills
    This refers to unsorted and heterogeneous mixture of rocks, clay and sand that are
    transported and deposited by the ice sheet on melting.
    They are of two types namely: lodgment and ablation tills
    Lodgment tills are deposited over the ice at the base as a glacier reaches its melting
    point and the ice moves. The moving ice aligns the debris onto the sub glacial surface
    Ablation tills are deposited when the ice melts
    iv. Kames and eskers
    Kames are isolated hills made of sand and gravel which have been deposited in layers
    by glacial water9
    They are built by streams emerging at high levels from temporary and stagnant ice
    covers.
    As the glacier front recedes, unsupported back of deposits collapses leaving a steep
    faced hill called kames
    Eskers are long winding ridge of coarse sand and gravel that is formed by streams that
    flow continuously beneath/within the ice but in a parallel direction to the moving ice
    As the ice front recedes, the streams continuously deposit the materials to form a long
    winding ridge called eskers
    v. Terminal moraines
    This is a long ridge of moraine formed by extensive deposition of moraine along the
    edge of an ice sheet.
    It is formed when the ice remains stagnant for a long time causing the ice at the edges of
    the ice sheet to melt
    vi. Outwash plain
    This is a wide and gently sloping plain of gravel, fine sand and clay
    It forms when large ice sheets stagnate on a gently sloping landscape and start melting
    along the edges.
    The sub glacial melt water spreads out carrying fine materials which are deposited
    further down slope as the ice retreats.
    Pre-existing valleys are buried by these fluvio-glacial materials.
    The unconsolidated clay, silt, sand and gravel are deposited in mass covering a wide
    area forming an undulating plain called an outwash plain
    vii. Drumlins
    These are smooth and long hills deposited and shaped under an ice sheet or a very
    broad glacier
    They are formed beneath the ice due to friction between the bedrock and the boulder
    clay.
    This results to deposition of clay at the valley bottom.
    Further deposition leads to large mounds of till forming
    The moving ice streamlines the till that had been deposited irregularly resulting into
    elongated egg-shaped hills called drumlins10
    Diagram
    Significance of Glaciation
    i. Outwash plains, old glacial beds and tills are at times very fertile thus leading to the
    development of agriculture e.g. wheat producing regions within the Canadian prairies
    ii. Some glacial lakes provide natural waterways e.g. the Great Lakes of Canada and North
    America thus facilitates transport and communication
    iii. Glaciers on highlands may form sources of river e.g. R. Tana on Mt. Kenya
    iv. Waterfalls resulting from hanging valleys provide suitable sites for the generation of HEP
    v. Glaciated mountain regions and their resultant features e.g. cirques, pyramidal peaks, etc.
    attracts tourists during winter for games/sports hence earning foreign exchange
    vi. Sheltered waters in the fiords provide suitable breeding grounds for fish and sites for
    construction of natural harbours
    vii. Sand for building and construction can be harvested from outwash plains, kames and
    eskers
    viii. Glaciation results into rugged landscape that makes settlement and construction of transport
    and communication difficult
    ix. Extensive areas of land are sometimes turned into glacial lakes by deposits from moraine
    thus reducing the amount of land available for settlement
    x. Some outwash plains may contain infertile sandy soils that hinder agricultural practices