MIGORI SUB COUNTY JOINT EVALUATION EXAM
GEOGRAPHY PAPER 1
MARKING SCHEME \SECTION A
1. a. Give three ways in which air pressure affect humidity (3mks)
- Pressure increase air temperature
- Hot air capable of holding more water than cold air
- High pressure increases the air holding capacity hence high humidity
b.State two factors that determine the amount of solar radiation reaching the earth (2mks)
2.
i.
Cloud cover
Transparency of atmosphere
Angles at which the rays fall
Nature of the surface
Average of distance of the earth from the sun
a. Study the world map below and answer the questions that follow
name the fold mountain found in the area marked A,B and C (3mks)\
A –Appalachian mountain
B- Rockies
C- Ural mountain
b.Give two negative effects of faulting (2mks)
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3.
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Land is disjointed leading to disruption of communication lines, water ,sewages and oil pipes
It leads to sinking of land hence loss of life, property and instruction of agriculture land
When faults occur across a river ,the river may disappear completely or change its direction of flow
Block mountains reverse drainage
a. Name two transitional zones of the atmosphere (3mks)
Tropopause
Stratopause
Mesopause
b.Give three reasons why cloud concentration is higher in the troposphere (3mks)
4.
-
Temperature decreases with increase in height
Presence of particles in the layer like dust act as condensation in nuclei
Has high humidity /water vapor
a. What is mass wasting? (2mks)
mass wasting is the creeping ,flowing ,sliding or falling of weathered rocks/materials down the slope
under the influence of free of gravity\
b.State three factors influencing the nature and speed of mass wasting ( 3mks)
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Amount of water in the weathered materials
Nature of the weathered materials
Angle or gradient of the slope
Presence of vegetation cover
Human activities e.g. mining and construction
Tectonic movements
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5.
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Climatic conditions especially rainfall and temperature
a. Name two current in the Atlantic ocean (2mks)
gulfstream
north Atlantic drift
b.State three factors that influence ocean water temperature
 latitude of ocean
 ocean currents
 the depth of the ocean
 salinity of the ocean water
 upwelling of water
 enclosed open seas
6. Drawing
ii.
Latitude and longitude of the south East cover of map extract
370154Eand 0030’s
iii.
Physical features found in Grid 0049
- Scarp /steep slope
- Spurs
- River valley
b.ii) On the graph
The two points are intervisible
c ii) Citing evidence from the map state 5 functions that favour livestock keeping in Karatina (5mks)
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Availability of many cattle dips indicate that there is access to veterinary services thus improve cattle
health
The high altitude – 2000m cost –warm conditions suitable for cattle rearing
Availability of transport shows by numerous road/track wet work enhance movement of cattle products
Presence of many rivers/source of water ensure enough water for cattle
Presence of dense settlement provide market for cattle products
iii) Describe the characteristics of the long river profile of river Sagana (6mks)
7.
The river has many small tributaries that forms dendrite pattern along the course
There are interlocking spurs along the river course/river meanders
The river is permanent
There are water fall/rapids along the course of Grid 8347
The river floors from North towards the South
The main tributaries are river Thego and Ruiru
The river becomes wider and wider Southwards as it’s joined by many tributaries.
a. What is a mineral ( 2mks)
Inorganic substances which occur naturally at or beneath the earth surface
ii.Classes to which the following rocks belongs
i.
ii.
iii.
Marble – Metamorphic
Basalt –Igneous
Ironstone –Sedimentary
b.i) How intrusive igneous rocks are formed (5mks)
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Heat and pressure beneath causes rocks to melt
This lead to formation of lines weakness cooling into the earth coast cooling into the earth coast
Magma cools and solidifies inside the coast to form intrusive igneous rocks
ii.Why coral rocks are widespread at the coast
a.
b.
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Salty water favour growth of coral polyps
Warm water with temperatures between 200c and 290c for the growth of coral polyps
Clear water which is free from silt or mud to your favour coral growth by receiving sunlight
Shallow water of less them 60 meters deep to which sunlight can penetrate for coral growth
Well oxygenated water for coral growth
Uses of soda ash
Catalyst /reagent for making soaps and detergents
Catalyst /reagent for making glasses
Making table salts
Used in the chemical industries
Is reasons to prepare objectives
Are a guide to possible areas of data collection
Are a guide on the actual activities to be carried out in the field
Help to ensure that all required data is collected
Restrict the researcher on the topic of study
ii.Four instruments and how they are to use them
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Hammers to break pieces of rocks
Shovel/spade to scoop out soil particles when digging out rocks
Fork jembe /jembe to dig out rocks
Panga to clear bushes so as to access rocks
Question 8: marking scheme
a) P-Limestone rock
Q – Grike
R- Clint
b) Factors influencing development of Karst sceweg
- The surface rock and the underlying rock should be thick limestone, dolomite or chalk
- The rocks should be hand and well-jointed
- The climate should be hot and humid
- The water table should be deep below the surface
c) Formation of
i.
A swallow hole (5mks)
- Is a vertical hole in the ground through which rain water or river water disappears into the ground
- The water widens and deepens the joints to form the vertical holes, as the water sinks through them
- The water that has disappeared through the hole moves along the rock joints until it comes out of the
ground as a veliclusion spring downhill
- When surface run-off or river water disappears into this hole, it is then called a swallow hole or a sink
hole
ii.
A doline (5mks)
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Is a round or elliptical hollow on the surface of a limestone region, formed when several small hollows
merge
- The small hollows are formed when water starts acting on the points of convergence of joints on the
surface ‘
- These points of convergence are widened as the solution process continues until the blocks of rock
between the hollows are completely dissolved
- This leaves a continuous rounded or elliptical depression called a doline
d) Influence of limestone landscapes on human activities
- Surface and underground features in a karst landscape can attract tourist thereby earning foreign
exchange
- Limestone landscapes are usually rugged with rocky surfaces, thin soils poor vegetation and inadequate
surface water, all of which discourage settlement
- Limestone blocks are used for building houses
- Limestone is also a raw material for cement manufacturing ,therefore it supports the construction and
manufacturing industries
c. i. Objectives of the study
- To find out the features formed in Karst landscape
- To identify the different features within the landscape.
- To establish the economic importance of such features
- To find out the effect of water action in limestone areas on settlement.
*any other relevant (2 x 1 = 2marks)
ii) Reasons why they needed to previsit the area
(1 mark)
- To estimate the time needed to do the study
- To estimate the cost of the study
- To enable them foresee the possible problems to be encountered while in the field
- To decide on the tools and materials to carry
- To obtain permission from relevant authorities
8. a. i) Outline two factors that influence the development of drainage patterns (2mks)
- Direction of the slope of the land
- Difference in the slope of the land
- The arrangement of rock layers /rock structure
- Faulting/fault guided
ii)Give three features of a river in its old stage
-
Pronounced meanders
Braided channel/river braids
Ox-bow lake
Estuaries
Flood plain
Natural leaves
Distributaries/deltas
Slip –off-slopes
Bluffs
Sagoons/lagonal lakes
Deferred tributaries
b) Briefly describe how the following factors influence river erosion
-
Gradient and velocity
The steeper the slope the higher the velocity and the more the rate of erosion and vice versa
Nature and amount of the load
A river carrying a large load and flowing at a high speed will be more effective in erosion work a river
carrying a small load and flowing slowly.
iii.
Nature of the bed rock (2mks)
- Less resistant bedrock are eroded faster than the more resistant bedrock
c. The diagram below represents a depositional features of a river .Study it and answer the questions
that follow
Diagram
i.
Name the parts labeled E,F, and G in the diagram
E – Lake
F – Main river
G - Alluvium swamp land
ii.
Give one example of the feature represented in the diagram in Kenya (1mk)
- A current delta
- Birds foot delta
- Estuarine delta
- Cuspate delta
- Inland delta
iii.
State three conditions necessary for the formation of the features shown in the diagram
- The river must have a large load of sediments
- There should be no obstacles like lakes or swamp along the rivers course as they tend to block sediments
from reaching the river mouth
- The river should the flowing slowly upon entering the sea ensure deposition of a lot of materials at the
river mouth
- The rate of removal of sediments by the tides and currents should be lower than the rate of deposition of
materials
d. A part from providing water for domestic and industrial uses, highlight three other benefits of
rivers in Kenya
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Provide fish which is food for human beings
Some rivers act as natural boundaries between countries communities and district etc.
River deltas and flood plains contain fertile alluvial soils suitable for agriculture
Rivers that are navigable provide route nays
Rivers leads provide building materials such as gravel and sand
Rivers provide fresh water used for irrigation
Rivers provide sites suitable for generation of H.E.P
River provided good sites for tourist’s attraction e.g. waterfalls.
e.Your class intends to conduct a filed study on river deposition around your school
i.
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Name one stage along the long profit of a river where your study can be conducted
The old stage
ii.
iii.
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State two methods you would use to collect data during the study (2mks)
Observation
Taking photo
Taking notes
Answering questionnaires
Give one benefits of river deposition that you intend to velocity during the study ( 1mk)
Valuable minerals e.g. gold and diamond
River deltas and flood plains which contains fertile soil for agriculture