NAKURU DISTRICT SECONDARY SCHOOLS JOINT MOCK EXAMINATION
JULY/AUGUST 2015
GEOGRAPHY MARKING SCHEME PAPER I
1. (a) Axis – an imaginary line through the centre of the earth from North pole to South pole.
(2 marks)
Orbit – The path in space which the Earth follows as it revolve/orbit round the sun
(2 marks)
(b) Earth, mars, Jupiter, Saturn, Uranus and Neptune
(3 marks)
2. (a) Orogeny is the period of mountain building while Orogenesis is the process of fold mountain
Formation
(2 marks)
(b) 




Atlas mountains of Africa
The Alps mountain of Europe
The Himalayas mountain of Asia
The Rocky mountains of North America
The Andes mountains of South America
3. (a) a- leached(soil with) lateritic cap
d – Thick (fertile) alluvial soil
(b) 





4.
(2 marks)
Provides anchorage for the plants
Protects roots from damage
Soil is a medium through which air, water and nutrients are made available to plants.
Soil is the rooting zone of plants
Pore spaces in the soil for good drainage is important for plant growth.
Soil temperature affects the roots indirectly by influencing chemical and biological
activities in the soil.
( 3 marks)
(a) Karst scenery are the striking features found in limestone areas (where the action of water on
limestone rocks dissolves the landscape)
(2 marks
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Nakuru District Sec. Schools Trial Examination @ 2015 Marking scheme Geography paper 1
4. (b)
Stalactite
Stalagmite
Underground
River
5 (a)




Physiographic/topographical factors
Edaphic/pedological factors
Climatic factors
Biotic factors
(2 marks)
(b)
 Forest vegetation
 Savanna grassland vegetation
 Arid and semi-arid vegetation/scrub
 Swamp vegetation
 Heath and moorland vegetation
SECTION B
6 (a)(i) Convert the ratio scale used in Migwani map to statement scale
(2 marks)
(2 marks)
1: 50 000
= 1cm: 50 000cm = 1 cm rep 0.5 / ½ km
100 000cm
(ii) Give the magnetic variation of the area covered by the map by the time the map was made.(2marks)
2o23’
(b)(i) Calculate the area enclosed by road C94 and road D502 to the North Western part of the map
F sq = 34
½ sq = 18 = 9
43 km2 ± 0.5
(2marks)
2
(Mark between 42.5 - 43.5 km )
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Nakuru District Sec. Schools Trial Examination @ 2015 Marking scheme Geography paper 1
(ii) Calculate the bearing of an air photo principal point in grid square 9575 from an air photo
principal point in grid square 9480
(2 marks)
170o ± 1o
(mark between 169o – 171o)
(iii) Give two natural features found in grid square 0382
 Rock outcrop
 Vegetation/scrub/scattered trees
 Hill
 River/Stream
(c) (i) Draw a rectangle measuring 10cm by 4cm to represent the area bound by Easting 90
and 00, and Northing 80 and 84
(1 mark)
on it mark and label: a school at Thokoa (1 mark)
 Kyoomi hill
(1 mark)
 a dry weather road (1 mark)
 a dam
(1 mark)
School
Dam
4cm
Hill
Road
10 cm
(ii) Citing evidence from the map, give four social activities carried out in the area covered
by the map
(4 marks)
 Education evidenced by the schools
 Health evidenced by Health centre
 Administration shown by chiefs office
 Religion shown by Church
(d) Describe the drainage of the area covered by the map
(6 marks)
 There are many rivers
 Most rivers are permanent
 Some rivers are disappearing e.g. to the West of river Ikoo
 The rivers to the North East forms dendritic drainage pattern
 Trellis drainage pattern is seen in the river to the Western side of the map.
 Rivers generally flows from North West to South East
 The main river is river Ikoo
 River Ikoo is in its old age stage
 There are several springs to the South of Mutito forest
 There are any dams along the rivers.
(1 x6 = 6 marks)
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Nakuru District Sec. Schools Trial Examination @ 2015 Marking scheme Geography paper 1
8 (a)(i) Faulting is the cracking/fracturing of rocks on the earth’s crust by the tectonic forces
(leading to permanent dislocation and displacement of rocks)
(2 marks)
(ii)
 Normal faults
( 1 x 3 = 3 mark)
 Reversed faults
 Tear, shear, slip fault
 A thrust fault
 An anticlinal fault
(b)(i) a – upthrow
b – Heave
c – Throw
d - Hade
(ii)
 fault scarp
 Block/horst mountain
 Tilt block
(c)
(1 x 4 = 4 marks)
t The land is subjected to
Compressional force d
compressional forces
Layers of rocks
Compressional force
t Reverse faults develop as
compressional forces push the land
Fault
d
Fault
\
d (diagram) = 4 marks
t (text)
= 5 marks
Total
9 marks
Compressional forces Rift Valley
d

f
d
Worn away by
denudation
f
The lateral blocks on either side of faults are pushed upwards t leaving the middle block
down t to form the depression which is the Rift Valley t
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Nakuru District Sec. Schools Trial Examination @ 2015 Marking scheme Geography paper 1
(d) 
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




causes disjointing of the land disrupting comm. lines water pipes/sewage / oils pipes
causes sinking of land leading to loss of life/property
Fault lines across a river valley may make the river to disappear into it or change direction
Faults are sources of minerals(veins)
At the base of a fault, springs occur
Hot springs and geysers associated with faulting are harnessed for Geothermal power
Sceneries associated with faulting e.g Rift valley attracts tourists which earns a country foreign
exchange.
 Vertical faulting across a river may cause water fall.
Any relevant points
(4 x 1 = 4 marks)
8. (a)(i) Weathering – breakdown and decomposition of solid rocks on the earth (through physical and
chemical processes) in situ (without movement) while mass wasting is downslope movement of
the weathered material by the aid of gravity.
( 2 marks)
(ii) Processes of chemical weathering




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Hydration
Hydrolysis
solution
Carbonation
Oxidation
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(b) Causes of soil creep
 Ploughing of land downhill
 Shaking by earthquakes or heavy trucks
 trampling and burrowing of animals
 Heating and cooling of soil
 Alternate drying and wetting of the soil
(5 marks)
(c) Negative effects of mass wasting
 Mass wasting causes rock fall or rock slide which leads to loss of life
 Mass wasting such as landslide or rock fall destroys property such as transport, communication
lines and other buildings
 Mass wasting facilitates soil erosion by removing soil vegetation cover which makes it unsuitable
for agricultural activities.
 Mass wasting leads to permanent scars on the landscape making it physically unsuitable for human
settlement
(any 2 x4 = 8 marks)
(d)(i)
 to identify the type of weathering in the area
 To find out the effects of weathering on human activities
 To find out the weathering processes in the area
(any 2 1 x 2 = 2 marks)
(ii) Methods of data collection
 Observation
 Carryout experiments
 Obtaining data from secondary sources(content analysis)
 Taking measurements
 Photographing/taking photographs
(any 3 1 x 3 = 3 marks)
9(a) Give four sources of water for lakes
 Rain water
 Rivers drainage in lakes
 Melt water from ice
 underground seepage
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Nakuru District Sec. Schools Trial Examination @ 2015 Marking scheme Geography paper 1
(4 marks)
(b) Describe how a corrie lake is formed
 A pre-existing hallow on mountain slope is filled with snow.
 Snow compact in the hallow
 Frost action/alternating freeze-thaw action enlarges the hollow
 Plucking process steepens the hollow
 Abrasion process depends the hollow
 Eventually deep arm-chair shaped depression results/corrie results
 When the corrie is filled with melt water it forms a corrie lake
(i) Identify he feature marked D
 Ox-bow lake
(ii) Explain three significance of the feature marked D to human activities
 Source of water necessary for domestic/industrial purposes
 Good breeding place for fish which is food to man
 marsh conditions can be harnessed for rice farming
 Stagnant water in the lake provide breeding place for disease causing organisms.
 Ox-bow lakes habours dangerous animals/crocodiles which attack man.
Accept any other relevant points
(7 marks)
(1 mark)
(6 marks)
(d) A form four class is planning to carry out a field study on the effects of flower farming on lake Naivasha
(i) State four reasons why it is important for the students to have a pre-visit of the area of study. (4 marks)
 To enable them draw study /hypothesis
 To identify possible objectives
 To enable them draw route map
 To enable them draw work plan/schedule so as to assemble necessary tools
 To enable to identify suitable data collection methods
 To familiarize with the area authority
 So as to prepare financial requirements
 So as to pin point suitable sites for the study
(ii) Give three follow-up activities students would carry out after the study.
 sketching the features
 Note making/writing field reports
 Answering questions/asking questions
 Discussing the findings
 Displaying photographs
 Analyzing data collected
 Drawing conclusions
 Watching video clips
 Listening to tape recorder
(3 marks)
10(a)(i) Differentiate between rocks and minerals
(2 marks)
Minerals are inorganic substances (that occur naturally) with specific chemical compositions and physical
characteristics while rocks are the agglomeration of mineral particles forming surface of earth /crust
(ii) Give two methods which may be used in estimating the age of rocks
 Relative dating
 Absolute dating
 Radio-carbon dating
(2 marks)
(b) (i) Describe the following characteristics of minerals
Lustre- minerals differ in their brightness depending on the nature of their reflective surface (2 marks)
Colour – Different minerals display different colours
(2 marks)
Density – minerals have different weight (per unit volume of water)
(2 marks)
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Nakuru District Sec. Schools Trial Examination @ 2015 Marking scheme Geography paper 1
(ii) The table below shows original rocks and metamorphic rocks. Identify the rocks marked X,Y and Z
(3 marks)
X – Quartzite
Y- Clay
Z- Gneiss
(c)
Describe three ways in which sedimentary rocks are formed
(6 marks)
Mechanically formed sedimentary rocks rock flagments are carried by water /ice/wind and
deposited in layers
Organically formed sedimentary rocks plants/animals remains are deposited then compact into
a hard rock.
Chemically formed sedimentary rock dissolved minerals are precipitated /overporated in the
water bodies then compact into hard rocks.
Way = 1 mark, explanation = 1 mark
Way can score without explanation but explanation cannot without way
(d)
Explain three importance of volcanic rocks to Kenyan economy.
(6 marks)
 Volcanic rocks are used for building houses
 volcanic rocks attract tourist who bring foreign exchange
 they weather to form fertile soils for agriculture
 Impermeable volcanic rock in the crust acts as water reservoir which is drilled for domestic use
 Some rocks e.g. pumice are used for washing and scrubbing feet domestically/locally
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Nakuru District Sec. Schools Trial Examination @ 2015 Marking scheme Geography paper 1