Download GEOGRAPHY PAPER ONE MARKING SCHEME A)(2 marks

GEOGRAPHY PAPER ONE
MARKING SCHEME
1. A)(2 marks)
- External surrounding which is made up of the features that are not created by
human beings a though their presence may have been influenced by human
activities.
B (3 marks)
- The earth and the solar system
- The internal land forming processes
- The external land forming processes
- Weather and climate
- Soil and vegetation
2. A)(2 marks)
- Extension boundaries is one where the tectonic plates are moving away from
each other while compressional boundary is one where plates move towards
each other
B (3 marks)
States that the earth was initially one liquid mass called pangea
It was surrounded by a great ocean called panthalasa whose floor was mainly
dima layer.
- During the late Precambrian period, Pangaea broke up into two blocks gurasia
and godwana land
- They were separated by a narrow ocean called Tethya.
- During Mesozoic era, Laurasia broke up into two; Laurentaian shield and
Fennoscandia
- Godwana land broke up into blocks, namely Africa Australia, the Americans,
Australia and the Indian dubeunlinents, Africa and India drifted northwards
while Australia drafted eastwards. The Americas drafted westwards.
3. A) (2 marks)
- Plant cover growing widely on its own without man’s influence
-
B (3 marks)
-
The vegetation is adopted to the long and dry summer
Some plants are ever green.
Grasses dry up during summer and germinate during winter
Scrubs, thickets, bush and thorn bush and maquis are common
Woody scrub is common in very dry areas.
Some plants have small, spiny leaves while others have thick skinned or leathery
leaves.
Some plants have long roots.
Some plants thick barks
Some plants large and fleshy bulbous roots
Some plants have fleshy leaves while others, have shiny, waxy leaves.
Some plants are deciduous
-
4. A) (1 mark)
i)
This is a zone that is prone to earth quakes
ii)
(2 marks)
Ray high waves cause rocks to move in elliptical orbits while love waves
cause rocks to move in a horizontal manner at right angles to the direction of
the waves.
B) (2 marks)
Evacuation of people from earthquake prone areas
Research on the prediction of earthquakes
High technology on the prediction of earthquakes
Introduction stricter building codes
Mark any relevant any
-
5. A)(2 marks)
- Heavy rainfall resulting to lubrication by the rainwater facilitate the movement
of the materials
- Tectonic movements – earthquakes and volcanic eruptions cause vibrations of
the earth which often trigger off landslides
- The angle of slope – the steeper the slopes, the faster the movement
B (1 marks)
i)
ii)
6. A)
i)
ii)
Solifluction
P = frozen sub – soil
Q = saturated top soil.
River
Rock out crop
9374
935747
(2 marks)
iii)
Area complete square 4
Incomplete square 13/2 = 12.5
Area 4 + 12.5 = 16.5 mk2 or 16 1/2 km2
(2 marks)
B
I)
Distance of the pond is D 502is 3.75 km
(3.7 or 3.8km )
II)
Breaking of mbooni dam
133 °± 1°
Direction SE (1mark)
Correction of 1 : 50,000
50,000 / 100,000 = ½ or 0.5 mk2
(NB/ must show working)
Eastern province
Kitui district
III)
IV)
(2 marks)
(2 marks)
(1 mark)
C) (5 marks)
- The central part is highly dissected
- The eastern part of the area is gentle
- The south western part has dissected hills (kitui hills)
- There are conical hills on the N. Western part.
- The river valleys are shallow and gentle.
7. A) (3 marks)
- Travertine
- Dolomite
- Rock salt
- Gypsum
- Haemitite
- Trona
B i) (3 marks)
ii.
-
Warm water whose temperature is between 20° - 30°
Shallow water with a depth of less than 60m
Saline ocean water / salty water
Clear and well oxygenated water / free from silt / mind free
Submerged conditions even at low tide
Describe how coral rocks are formed (4 marks)
Tiny marine organisms called coral polyps live in colonies in the sea
-
Polyps extract calcium from the sea water to make their shells
The spaces between the dead coral polyps are cemented by calcareous algae.
C) (8 marks)
-
Some locks are exploited to provide building and construction material.
This promotes the industry
Some rock formations e.g. granitic tors are tourist attractions. This earns
the country some foreign exchange.
Rocks have contributed to the development of cement industry through the
provision of limestone as raw materials.
Through weathering rocks provide soils which are useful for agricultural
production
Some rocks have valuable mineral ores which are exploited and sold to
generate revenue.
Some rocks are e.g kisii soapstone is used for making carvings.
Some provide salts used for both domestic and industrial purposes e.g soda
ash in lake magadi.
Fuels of great economic value are derived from rocks e.g coal and
petroleum
Rocks act as water researches through aquifers. This can be harnessed for
domestic and industrial purposes.
Sedimentary rocks contain nitrates ad potash used in making of fertilizer,
medicine and dyes.
D) I) (3 marks)
-
Textbooks / pamphlets
Journals
Periodicals / magazines / news papers
Teachers / handouts.
ii. (4 marks)
-
Setting up objectives for study
Identifying methods of data collection
Carrying ant a reconnaissance survey
Seeking permission from relevant authority
Identifying /sorting out relevant equipments, tools for the study
Drawing a route map
Identifying relevant stationary
Dividing themselves into groups
-
Discussion
8.
a)
i.
State the factors that determine the size of a lake in an area.
- The size of the depression.
- The inflow of water from rainfall and rivers
- Outflow of water from the lake through rivers or
evaporation.
ii.
-
They have no outlets therefore salts accumulate in
them.
They are found in areas of high temperature thus
making the water saline.
Some lakes have soluble bed rocks which contribute
some salts.
Vulcanizing some salts to the lakes thus making them
saline.
(2marks)
b)
i.
-
-
Lava damned lakes- they are formed in areas that
experience volcanicity . When lava is released from a
mountain, it may also flow across a river valley ,
thus cotting off the river from flowing down stream
by forming a barrier across it.
Water then accumulate on the upstream side of the
lava barrier to some lake known as lava dammed
lake eg lake Bunyonyi, Mutanda, Kenyumba and
Buleva.
Ox-bow lake
An ox bow lake is formed by river deposition.
- At the old stage of a river , the river begins to
meander due to reduced gradient.
- Due to erosion along the concave bank the
meanders become pronounced.
-
-
During the high season then meanders cuts
cut off due to increased volume and
increased erosion.
Deposition along the new channel thus
cutting off the meander completely from the
river and this water within the meander then
forms an ox-bow lake.eg Shikababo, Gambit,
Bilisa, Mukunguya and Kanyaboli.
ii)
-
-
Agricultural activities such as crop farming around
the lake may release herbicides and pesticides due to
run-off and this may lead to the death of fishing the
lakes due to pollution
Fertilizers used in the farms may be drained into the
lake thus eroding in the lakes.
Industries may ------------- into the lakes thus causing
pollution.
Farming activities through irrigation may reduce
water inflow into the lakes thus reducing their size.
(3marks)
c)
i)
-
Porous rock refers to a rock that has mainly airspaces
within it while a previous rock is the one that has
crack within it.
(2marks)
ii)
a) –Agoifer
b) –Artesian well
c) _non porous rock/ cap rock
(3marks)
iii.
- Porous rock must be sandwiched between two layers
of impermeable rock.
- The permeable layer must outcrop on one or both
ends in a region which is a source of water lake or
highland .
- The whole structure must form a basin for water to
be retained at the lowest level.
d)
- Underground water provide sites for settlement eg spring line
-
Water from wells can be used for irrigation in dry areas.
Springs form sources of water for domestic purposes and
industrial purposes.
Springs are sources of various rivers.
Underground water may form geysen which can be used for
production of which H.E.P
(3marks)
9.
a)
i)
ii)
iii)
A desert to refers to an area with very low rainfall which is
barren and cannot support vegetation adequately while
desertification refers to slow but gradual spread of desert
like condition into an area that was formerly production.
(2marks)
This is the process whereby material load carried by the
with transport thus splitting and reducing in size.
In the process it gets polished.
- Deflation: It is a process whereby wind removes dry
and unconsolidated material especially dust and
sand by lifting and rolling.
- With time the material are removed and taken
elsewhere.
At the end
b)
i)
-
Yardangs are long narrow ridges that are formed in
desert areas where alternative had and soft rocks lie
vertically or inclined and parallel to the direction of
prevailing wing.
Diagram
Explanation (2marks)
As the wind blows it erodes by labanion and deflation the soft
rock leaving the hard rock standing out as ridges between
forrows . The ridges are then known as yardangs .
Diagram
ii)
-
Suspension
Saltation
Surface area
(3marks)
c)
i)
ii)
Self dune
-
-
These are elements formed in desert areas which are
long and parallel to reach other separated by roughs.
They are formed in areas where there are prevailing
winds which are interrupted by strong cross-winds.
The cross-winds divide the sand side by side thus
heading them into long parallel done which are
separated from each other by trough.
The ridges of sand are then known as safe.
(3marks)
d)
i)
-
The unconsolidated material in deserts makes it easy
to erode through water action.
The seauce vegetation facilitates water erosion in
deserts.
Nature of rainfall which is spread ie unreliable and
torrential encourages water erosion in desert
-
The areas are rugged thus encourage water action in
deserts. (2marks)
ii)
-
Water from the oasis can be used for irrigation thus
encouraging agriculture.
Form fertile alluvial soils for agriculture.
Desert features are a major tourist attraction thus
encouraging tourism.
Desert features can inhibit physical development in an
area eg wadie discourage the development of transport
and communication facilities.
(3marks)
iii)
Strength and force of the wind.
Degree of resistance of the rocks
Amount and nature load carried by the wind.
(3marks)
10. 8uui
-
a)
i)
ii)
Soil catena refers to the to the arrangement of soil along a
slope from top to bottom while soil profile refers to the
parent rock. (2marks)
Diagram
b) Parent rock
- It determines the soil color
- It determines the rate of soil formation by determining how
fast the parent rock withers down.
- It determines mineral content hence fertility.
- It determines soil texture whether course textured or fine
texture.
Topography
- It determines the formation and depth on gentle slopes;
soils are deep while on steep slopes thin.
- Gentle slopes retain water longer therefore poorly
drained.
Gentle slopes are more fertile due to soil deposition
while sleep slopes are infertile due to erosion.
(3marks)
-
c)
i)
-
Prismatic structure
Crumb structure
Platy structure
Columnar structures.
(4marks)
-
-
It provides plants with food mineral nutrients eg
calcium, magnesium, nitrogen and phosphorus.
It provides food for soil micro-organisms.
Provides habitat / home for soil micro- organisms.
It provides acids (organic acids which help in
weathering )
It helps to retain soil moisture.
It helps to prevent soil erosion.
Promotes the development of soil structure.
It helps in water and air circulation.
-
They are thin and shallow.
They are sandy or rocky.
The soils have low human content
Desert soils are mainly saline.
ii)
-
iii)
(4marks)