312/1

GEOGRAPHY 

Paper 1

2hrs 45mins

Kenya Certificate of Secondary Education

 SECTION A

Answer all questions in this Section

1. (a) Define Fog. (2 marks)

• This is a cloud lying in contact / very close to the surface of land / sea;

(b) State three conditions for formation of dew. (3 marks)

• Cloudless night to accelerate het loss gained during the day;
• Warm day to accelerate evaporation;
• Calm air to remain in contact with the ground long enough to be cooled below the dew point;

1. (a) Give three examples of west coast deserts. (3 marks)

• Atacama desert;
• Namib desert;
• California desert;

(b) Describe the process of wind deflation. (2 marks)

• Dry unconsolidated and fine materials are rolled on the ground and lifted up in the air by wind;

Use the diagram below to answer question 3

1. (a) Identify the type of weathering. (1 mark)

• Exfoliation;

(b) Describe how the process occurs. (4 marks)

• A homogenous rock is exposed to intense heating during the day and cooling during the night;
• The outer layers are heated expanding faster than the inner rock layers during the day and cooled contracting faster during the night;
• Repeated heating and expansion followed by cooling and contraction creates a stress within the rock causing a fracture parallel to the surface;
• With time the outer rock layer peels off in a curved manner leaving the rock mass beneath intact;
• This is exfoliation;

1. (a) State three causes of dynamic river rejuvenation. (3 marks)

• A drop / change in the sea level;
• Regional / local uplift of the land;
• Unequal regional subsidence of the land;

(b) Give two rivers in Kenya where in trenched meanders are found.

 (2 marks)

• River Mara;
• River Kuja;

1. (a) Define magnitude of earthquake. (2 marks)

• This refers to the amount of energy released by earthquakes;

(b) Give three types of earthquakes. (3 marks)

• Shallow focus;
• Intermediate focus;
• Deep focus;

SECTION B

Answer all question 6 (compulsory) and any other two questions from this Section.

1. (a) (i) State the map title. (1 mark)

• East Africa 1:50 000 (Kenya);

(ii) Convert the maps linear scale to a statement scale.

 (2 marks)

• 2cm represents 1km
• 1 cm represents ½ km
• 1cm represents 0.5km

(iii)Locate the air photo principal point labeled 58 (grid 8235) using latitudes and longitudes. (2 marks)

• Latitude = 00351
• Calculation of longitude
• 18.3cm = 51
• 5.3cm = ??
• Longitude = 340 401 – 21 = 340381
• Location 00351S, 340381E

(b) (i) Name any three drainage features in Oyugis map. (3 marks)

• Rivers;
• Water reservoir;
• Seasonal swamp;

(ii) Calculate the bearing of Ongala School in Genga from Disi School. (2 marks)

• Bearing of Ongala School from Disi School;
• 0630 +10
• (0620, 0630 0640)

 (iii) Measure the distance of all-weather road loose surface C20 from the junction in Rodi Kopany to the junction at Nyarach School. (Give your answer in metres) (2 marks)

• 16.8km X 1000
• 16800m; (16700-16900)

(c ) Draw a sketch section along Northing 36 between Eastings 67 and 76. On it mark and label 

1. River,
2. Water reservoir,
3. Hill 

 (7 marks)

(d) Citing evidence from Oyugis map, explain three factors that are responsible for dominance of brickworks in Oyugis. (6 marks)

• Alluvial soils / clay soils along river Riana that is used in making bricks;
• Availability of water evidenced by many permanent rivers e.g. Riana that is used in mixing soil for brick making;
• Availability of market evidenced by many settlements that consume bricks;
• Availability of accessible transport network evidenced by all-weather road loose surface C20 that easens delivery of bricks to the market;

1. (a) (i) Define Aspect. (2 marks)

• This is the direction of which a slope faces with references to sunlight;

(ii)Describe how forests influences climate. (4 marks)

• Forested areas have low temperature due to the shade provided by trees;
• Forested areas have high humidity due to high rate of evapotranspiration; 
• Forested areas have / experience high rainfall due to to high rate of evapotranspiration and friction between trees and rain bearing winds;
• Forested areas experience weaker winds since trees are windbreakers; 

(b) Study the map of Africa and use it to answer questions that follow.

1. Name the climatic types in the following towns. (3 marks)

• Johannesburg – warm temperate continental interior;
• Cape town – warm temperate western margin;
• Durban – warm temperate eastern margin;

1. Describe the characteristics of the vegetation type found in the region marked A. (7 marks)

• Composed of shrubs and thicket;
• Grass dry off during winters and summer;
• Some trees are deciduous;
• Some plants have freshly leaves;
• Some trees have thick and rough barks;
• Plants have long tap roots;
• Most plants are evergreen;

1. State any four characteristics of rainfall in the area marked B. (4 marks)

• High rainfall throughout the year;
• Rainfall is well distributed throughout the year;
• Rainfall regime is double maxima;
• Convectional rainfall is mainly experienced / relief in mountainous regions;

1. Your class went for a field study to the region marked R. State any five features of plants you could have observed in the area. (5 marks)

• Plants have succulent stems;
• Plants have thick leaves/ folded leaves;
• Plants have deep roots;
• Some plants are deciduous / shed their leaves;
• Most plants have thick waxy cuticle;
• Some plants have shallow roots;
• Plants have small and thorn like leaves;

1. (a) (i) Define a Spring. (2 marks)

• Water that flows out of the ground naturally at a particular point;

(ii) State three ways through which a spring may be formed. (3 marks)

• When a permeable rock lies above an impermeable rock;
• Where a dyke cuts across a layer of permeable rock;
• Where a well jointed rock outcrops in a hilly area;

(b) (i) Give four characteristics of a Karst landscape. (4 marks)

• The area has no surface drainage e.g. river;
• The area has rock outcrop which are rugged;
• The area has many depressions formed by solution;
• The area has many underground streams;
• The area has residual hills;
• The area has underground caves;

(ii)Outline three areas in East Africa where Karst landscape is common. (3 marks)

• Tanga in Tanzania;
• Ramisi in Kenya;
• Shimoni in Kenya;

(c ) Describe the formation of the following features.

1. Uvala (5 marks)

• Rainwater absorbs carbon (iv) oxide in the atmosphere forming weak carbonic acid;
• As rainwater percolates through the rock it erodes it through solution;
• Further solution leads to merging of several joints to form a doline;
• Several dolines existing adjacent to each other may join due to further solution form a very large depression;
• This is an uvala;

1. Pillar (8 marks)

• Rainwater absorbs carbon (iv) oxide from the atmosphere forming a weak carbonic acid;
• The acid dissolve calcium carbonate as it infiltrates through the limestone rock forming calcium bicarbonate;
• The solution of calcium bicarbonate percolates through the cracks ad joints into the cave;
• Water and carbon (iv) oxide are released to the atmosphere due to high temperature leaving behind calcium carbonate which grows downwards forming a stalactite at the roof of the cave;
• Some solution of calcium bicarbonate drips on the floor of cave;
• Water and carbon (iv) oxide are released due to high temperature leaving behind calcium carbonate which grows upwards forming a stalagmite;
• Stalactites and stalagmite join as more deposition takes place to form a pillar;

1. (a) (i) Differentiate a Stack from a Stump. (2 marks)

• A stack is an isolated rock pillar in the sea which was once part of a head land while a stump is a small rock pillar in the sea that was once a stack and only visible during low tides;

(ii) Study the diagram below and us it to answer the questions below.

1. Name the features marked E, F and G. (3 marks)

• E – blowhole;
• F – cave;
• G – cliff;

1. With the aid of a well labeled diagram, describe how a geo is formed. (10 mark)

• Breaking waves erodes the base of a cliff through abrasion to form anothc;
• Further wave action enlarges the notch to form a cave;
• Solution and wave action act on the root of a cave to form a blowhole;
• Continued wave erosion enlarges the blowhole and weakens the roof of the cave;
• Eventually the root of the cave collapse forming a narrow sea inlet;
• This is a geo;

Note: description 6 marks, diagram 4 marks

1. Describe how coral coasts are formed. (6 marks)

• Coral polyps live in gravel colonies in an area;
• They make their shelves by extracting lime from the sea;
• When they die, their shelves accumulate into solid mass;
• Further accumulation leads to compression of lower layers;
• Their skeleton are cemented together by colcarons algae to form a hard rock;
• This is a coral coast;

1. Your class went for a field study on the nature of ocean water
2. Identify two characteristics of ocean water you are likely to study.

• Salinity;
• Temperature;

1. State two problems you are likely to experience

• Difficulty in movement due to presence of sand;
• Insufficient water for drinking;
• Attack by reptiles/wind animals;
• Accidents e.g. falling / being cut by rock outcrops;
• Fatigue;

1. (a) (i) Define the term Glaciation (2 marks)

• This is the action of moving ice and the changes that take place on land as it moves;

 (ii) Name any three ways through which ice move. (3 marks)

• Plastic flowage;
• Internal shearing;
• Extrusion flow;
• Basal slip;

(b) Describe how the following features are formed. 

1. Eskers (7 marks)

• A mass of ice stagnates in a lowland;
• The ice melts at the base forming a stream of water;
• The melt water erodes the earth surface vertically forming a channel through which it flows;
• Large boulders are deposited in this channel;
• When ice melts completely, more materials are deposited in the channel;
• Eventually a long winding steep sided ridge of sand and gravel is formed;
• This is an esker;

1. Terminal moraine (7 marks)

• Glacier moving towards a lowland erodes the valley sides by abrasion and plucking;
• It carries with it solid materials and stagnates on reaching the low land;
• More accumulation of glacier occurs;
• Upper layers exerts pressure on the lower layers and edges leading to melting;
• The melt water will release its load and deposit it at the end of the material;
• With time an irregular long ridge extending across landscape is formed;
• This is a terminal moraine;

(c ) Explain three negative effects of glaciation to human environment. (6 marks)

• Boulder clay deposit in lowland lead to formation of marshy landscape which is poorly drained hence discourage agriculture;
• Some glaciated landscape are rugged making agriculture / settlement / transport difficult;
• Glaciated lowlands have numerous lakes which reduce land available for human activities;