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GEOGRAPHY
PAPER1
July/August 2009
JOINT INTERSCHOOLS EVALUATION TESTS
JISET 2009
MARKING SCHEME
GEOGRAPHY
Paper 1
July August 2009
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SECTION A
1. a) i) “Geo” means the earth surface
ii)
Areas of great interest to a physical geographer are;
-The earth and the solar system
-The internal land forming processes.
-The external land forming processes
-Weather and climate
-Soil and vegetation
(1mrk)
(1x2) =2mks
b) i) A rock is any naturally occurring agglomeration of mineral particles forming part of the
earth crust
(1mrk)
ii) Sub-divisions of igneous rocks are;
-intrusive (plutonic) rocks
-Hypabyssal (intermediate) rocks
-Exclusive volcanic (rocks)
(1x3) =3mks
2. From the diagram
M
- Epicenter
Q
- Shock waves
N
- Focus
(1x3) =3mrks
0
3. The barysphere has temperature of about 5500 c because;
- The weight of overlying material exerts pressure on the earth’s core thus leaching to high
temperature.
- The original temperature is still retained after the earth’s interior cooling at a much slower
rate than the outer part.
- Radioactivity i.e. process of breaking the nuclear of an atom through nuclear fussion
(1x3)=3mks
(b) Two types of mass wasting
i) Slow mass wasting e.g. soil creep,sceel\ Talus creep and solifluction
ii) Rapid mass wasting e.g. Earth flows, mud flows, avalanches and land slide
(2x1) =2marks
4. (a) Processes through which river erosion occurs;
- Hydraulic
- corrasion
- Attrition
- Saltation
- solution
(b) Factors leading to reduction in rivers competence and capacity to transport the load are;
- -Reduction in stream gradient
- Decrease in volume of water
- loss of velocity
- Obstacles in stream channel
- Widening of stream bed
- Overloading
- Freezing
- Emptying into quiet/slow moving bodies of water
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5. Soil catena is the arrangement of soil on a mountain slope from top to bottom. The top of the
mounting has latent cap, the slope has light soil and the bottom thick deposited soils.
(Diagram 3marks, Text 1mark=4marks)
SECTION B
6. a) (i) Social amenities within Kericho municipality ;
- schools
- Hospitals
- clubs
- colleges
- racetrack
(1x2) 2mks
(ii) Direction of the factory a long easting 61 from trigonometric station 2173 is
- south east
(1mrk)
(iii) Distance in kilometer of the dry weather road from Grid square 5460 up to where it meats
all
weather road loose surface in the Grid square 5168 is 9.8km ±0.1km
(2mks)
b) i) A cross section a long Grid references 620670 and 670640 showing All weather road to
Lumbwa river valley and Tea estate
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V .E 
V .S
1cm rep. 40m

H .S 1cm rep. 50,000cm

ii)
V .E 
1
1
1
50,000



40  100 50,000 4000
1
(2mks)
50,000
 12.5
4,000
c) i) Methods used to represent relief area;
- contours
- Trigonometric station
ii) Describe relies in the area covered by the map;
- Generally the area covered by the map has high attitude over 220m as shown by the
contours
- Most regions to the south and south west of the area covered by the map are gentle slope as
indicated by the contours that are a part.
- There are steep slopes in the north and north east of the area covered by the map(2x1)
=2marks
d) Economic activities a part from Tea growing and their evidences from the map.
Economic activities
Evidence from the map
- Transport
-Roads
- Trade
-market centre, shops and roads
- Forestry/lumbering
- Kericho forest station (grid 6361)
(Activity -1mark Evidence-1mark Total =6marks)
e) -To find out the type of rocks used for building purpose.
-To find out problems facing rock extraction in the area covered by the map
-To examine how rocks affect settlement in the area covered by the map.
-To find out the type of soil found in the area covered by the map
-To establish the type of weathering that might have occurred in the area
-To find out economic importance of rocks in the area covered by the map
(Any other relevant -1x3=3marks)
7. a) i) Distinction between mass wasting and mass movement
-mass wasting is the down slope movement of rock materials due to the influence of gravity
while mass movement is the down slope movement of weathered materials after such material
has been lubricated by water or snow
(Any difference 1x2=2marks)
ii) Examples of rapid mass wasting
-Earth flows
-Mud flows
-Avalanches
-Land slide\land slips
(any two 1x2 = 2marks)
b) Factors that influence weathering are;
-Slope \ Gradient \ Topography \Relief
- The steeper the slope the higher the rate of weathering and the gentler the slope the slower
the rate of weathering since it explains the speed and the nature of movement
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-
-
Climate-:Climatic element such as sunshine, rain, frost and temperature initiate weathering
.Different regions of the world experience different climatic conditions hence different
weathering processes
Plants and animals; barrowing animals like rodents initiate weathering .plants roots
penetrate through cracks of rocks thus facilitating weathering
Chemical composition of rocks; it involves the colour and planes of weaknesses in rocks.
Dark colored rocks absorb heat hence break easily compared to light colored rocks.
Joints bedding etc determine the type of weathering.
The structure and Texture of rocks –the plane of weaknesses like joints, cracks bedding and
exfoliation are vital media through which physical and chemical processes can penetrate a
rock hence facilitating weathering
(any 3x2= 6mrks)
c) Processes involved in chemical weathering;
-Hydrolysis –Is the process where chemical reaction takes place between hydrogen
ions in water and minerals in a rock e.g. felspar rock reacts with water and silica is
removed in solution to form clay ,This weakens the rock.
-Hydration – is the processes where some minerals in a rock take up water and expand causing
stress in the rock, which leads to fracturing of the rock.
-Solution –Is the processes where some rocks material dissolve in water and washed away in
solution. This leaves behind a weaker rock.
-Carbonation –Is the process by which water with carbonic acid dissolves calcium bicarbonate which is a solution and this leaves behind a weaker rock.
-Oxidation-Is the processes by which oxygen in air reacts with ions compounds in rocks.
ferrous state of iron minerals change into ferric state which weakens the rock
(Any 3x2=6marks)
The
d) Field on weathering in north eastern province
(i) Reasons for having a working schedule
- It gives ample time to each activity so that no activity is forgotten
- It provides an estimate of the time required for the study
- It provides a basis for evaluating the study while in progress
- It provides a frame work which guides a researcher to remain within the scope of
study
- It reduces the tendency to waste time
(Any 3x1 = 3marks)
(ii)
(iii)
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Physical weathering processes they are likely to study;
- Pressure release \ unloading.
- Exfoliation
- Block disintegration
- Crystal growth
- Granular disintegration
iii) Methods they would use to present data;
Writing a report
Displaying labeled samples
Displaying photographs
Giving a lecture
Playing tapes
Drawing sketched maps and diagrams
(Any 3x1 = 3marks)
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- Drawing charts and graphs
- Displaying the completed questionnaires
(Any 2x1 = 2marks)
8. a) i) Aridity is the condition of rainfall deficiency in an area. it is characterized by irregular
rainfall, little vegetation cones and excessive evaporation in comparison to precipitation.
(2marks)
ii) Wind is air in horizontal motion. The motion is created by difference in temperatures so that
air moves from colder areas to warmer areas.
(2marks for full definition)
b)i) Ways in which winds erodes weathered materials in arid areas;
-Deflation –Is the process by which wind moves dry unconsolidated materials like dust and
sand from surface of the earth by tilling and rolling which depends on wind
velocity
-Abrasion-Is frictional or mechanical weathering down of rocks by wind borne materials like
coarse sand which is the erosion tool
-Attrition –Since water borne materials are at constant state of movement they rub against
rocks and each other to produce rounded sand.
(2x3=6marks)
ii) Five features under arid condition as of wind erosion
- Deflation hollows
- yardangs
- zeugens
- Rocks pedestals
- vent facts
- inselbergs, millet-seed, gours, desert pavements
 (any 5x1= 5 marks )
c) Factors influencing wind transport in a desert;
- Speed and the force(strength) of the wind.
- Nature of the load i.e. either light or heavy.
- intervening obstacles e.g. dead animals, twig or rock
- water mass and vegetation
(1x4= 4marks )
d) i) Resultant features of water action in arid areas
- Wadis
- pediments
- Bajada
- playas
- inselbergs
- selinas
- mesas and buttes
- Dry river-valley
- pediplains
(2x1=2marks)
ii) Formation of wadi .
-These are steep dry hollows in an arid area formed when flash floods occur on a steep
and undulating landscape. The flash flood cut rills which in turn developed into gullies.
The stream enlarges the gullies rapidly to produce steep sided valley called wadis.
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9. a) two types of earth movements
-Horizontal earth movement  (1)
-vertical earth movement (1
1x2 =2mrks
ii) Two forces responsible for the above movements
-Tension force (1
-Compression forces  (1
-Shear.
 (1
Any two 1x2=2mrks
b)
P
Q
R
-
up throws (1
Fault scalp  (1
down throw (1
1x3=3mks
c) Using a well labeled diagram describe how a Rift valley is formed through the theory of
compression
-Crustal rocks are subjected to compression forces  ( ½ )
-As compression forces continue to push the crust together points of geological develop
leading to the formation of adjacent reverse faults ( ½ )
-As compression continues the outer blocks rise along the fault and then override the
middle block leaving it to form the floor of the Rift valley ( ½ )
-The Rift valley formed has overhanging scarps which are immediately worn away by
denudation
1\2 x4 =2marks
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d) Explain the following types of faults;
Normal fault
(2marks)
-Crustal rocks are subjected to tension forces.
-When tension forces continues points of weakness develop
-One block subsides leading to the formation of a normal fault
ii) Reverse fault
(2marks)
-The crustal rocks are subjected to compression forces
-When compression forces persist, points of weaknesses develop
Leading to one block overrides the other forming a reverse fault
1\2x2=1mrk
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e) i) Preparations before the study
3marks
-Identify the specific area in the Rift valley
-Seek permission from the relevant authority eg school.
-State the objectives
-Formation of hypothesis
-Carry out a reconnaissance study
-Identify methods of data collection to be used
-Assemble equipment and tools to be used during the study
-Organize for transport means and subsistence
Plus any relevant
Any 3x1 = 3mks
ii)Four features likely to be identified
-Fault scarps\ escarpment
-Tilt blocks
-Fault steps
-Rift valley \fault guided lakes
-Horst \block mounts
Plus any relevant features
Any 4x1 = 4mks
f) Three significance of faulting to human activities
3mks
-Leads to formation of waterfalls that can be exploited to generate H.E.P
-Features formed through faulting e.g. Rift valley are a tourist attraction which earns
country foreign exchange
-Rift valley lakes provide water for industrial and domestic use
-The high lands e.g. block mounts modify the climate of the area making it suitable
agriculture
-Small Rift Valley from low lands may be suitable for settlement and agriculture.
-Along the faults are found minerals deposits which can be exploited for industrial
development
plus any relevant point 1x3=3mks
a
for
10) i) Factors which affect the occurrence of underground water
-Precipitation amount received in an area.
-Evaporation rate in an area
-Porosity of rocks in an area
-The slope of the land
-Amount of the vegetation cover in an area
(1x3=3mks)
ii)
Conditions necessary for occurrence of artesian basin
-There must be exist a rock structure that forms a shallow syncline or
depression
- An impermeable rock strata must be above and below permeable rock strata
-The permeable rock (aquifer) must be exposed at one end or both ends.
(1x3=3mks)
iii)
Differentiate between a permanent well and intermittent well
-A permanent well is a hole sunk into a permeable rock up to below the water table and
it contains water throughout the year. While a seasonal \ intermittent well is a hole sunk into a
permeable rock but not below the water table ,it contains water only in the rainy season.
(2x2=4mks)
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b,i)
Surface feature of the karsts landscape are
-Dry valleys
-Grikes\ grykes
-clints
-shallow holes or sink holes
-Dolines
-u valas
-polje
-Terra rossa
(3x1= 3mks)
ii) Differentiate between stalactite and a stalagmite
- Stalactite are underground fingerlike masses of calcite hanging vertically from the roof of a
cave .while stalagmite are underground stumpy rock masses which grow from the floor of
the cave upwards .
(2x2 = 4mks )
b iii) Significance of underground water
-Springs are sites for settlement in the chalk escarpments e.g. kambe in kilifi district
--Water from wells is used for irrigation in dry areas.
-Springs forms major sources of water for both domestic and industrial uses e.g. mzima
springs supplies water to Mombassa
-Hot springs and geysers attract tourist and are also tapped to produce geothermal power
(2x2 =4marks)
c) Reasons for conducting a pre-visit
- It familiarizes the researchers with an area of study
- It helps the researcher to Identify and decide on the methods and tools to use in collecting
information
-It helps in determining the suitability of an area of study.
-It helps to identify any problems the researcher is likely to encounter during the study
-it enables the researcher to estimate the cost of study and plan accordingly
-It is useful in designing a work schedule
-It introduces the researcher to the authorities and respondents in the area of study
4x1=4marks
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