1. (a) Give the dates when the sun is overhead along the equator

• \(21^{st}\) March ✓
• \(23^{rd}\)  September ✓

(b) State three characteristics of SIAL layer of the earth’s crust

• Rocks are mainly granitic ✓
• The rocks are brittle / ~~rigid~~ on folding they tend to crumble. ✓
• It is lighter / less dense ~~floats on the inner crust.~~ 2.7g/cc
• It floats on SIMA. ✓
• It forms the continental layer. ✓
• It is approximately 70 km thick. ✓
• It is made up of silica and aluminium. ✓

2(a) Explain the term rock as used in Geography?

• It is a natural combination / ~~agglomeration / aggregate~~ of mineral particles that form the solid part of the earth’s crust. ✓✓

(b) List two examples of plutonic rocks

• Granite. ✓
• Diorite ✓
• Gabbro. ✓
• Peridotite ✓
• Syenite. ✓
• Nephline. ✓

3. The following diagram shows a simple fold. Use it to answer question 3(a)

(a) Name the parts ~~marked~~ labelled E and F.

• E-Axis / ~~axial plane~~. ✓
• F-Trough / Syncline / Basin. ✓

(b) Give three factors that influence folding.

• • Strength of compressional forces ✓
  • Elasticity of rocks / temperatures in the rocks. ✓
  • Age of rocks. ✓
  • Thickness of the overburden. ✓
  • Type of rocks. ✓

4.(a) Identify two ways of measuring the strength of an earthquake

• Intensity. ✓
• Magnitude. ✓

(b) State three natural causes of earthquakes

• • Movement of magma within the earth's crust / volcanic eruptions. ✓
  • Folding / faulting. ✓
  • Isostatic adjustment. ✓
  • Energy release within the mantle. ✓
  • Divergence / Convergence / Shearing of tectonic plates / ~~Gravitative pressure~~ Tectonic movements. ✓
  • Gravitative pressure. ✓
  • 
    

5. (a) Name three soil forming processes

• Weathering. ✓
• Leaching. ✓
• Decomposition. ✓
• Deposition. ✓

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(b) Give the three types of soil degeneration.

• • Chemical degeneration. ✓
  • Physical degeneration. ✓
  • Biological degeneration. ✓
• 
  

6. Study the map of Kipkabus 1:50,000 (sheet ~~no.~~ 104/1) provided and answer the following questions

a(i) What ~~is~~ was the magnetic variation of the area when the map was drawn?

• \(2^{∘}08’ \) ✓

(ii) Name the ~~two~~ types of scales shown on the map.

• • Linear scale. ✓
  • Ratio scale / RF ✓

(iii) What is the direction of the Air photo principal point 87 in grid square 8338 from the trigonometrical station primary SKP 102?

• • North west ✓✓ /  \(298^{∘}±2^{∘}\) /  \(N62^{∘}W±2^{∘}\)

(b) Measure the distance of the dry weather road from grid reference 867365 to 829420. Give your answer in kilometres.

• 7.2 km±0.1 (7.1−7.3) ✓✓

(c) Using a scale of 1cm to represent 20 metres draw a cross-section from grid reference 785320 to 850320. On the cross section, mark and label the following.

• (i) main track (motorable)
• (ii) forest boundary
• (iii) river
• (iv) gentle slope

• There are many permanent rivers. ✓✓
• The main rivers are R. Kimwarer and R. Kiptunoi.
• There are lakes. ✓
• There are seasonal swamps in the west, and south west and north west / west part of the area covered by the map. ✓
• There is papyrus swamp in the western part of the map. ✓
• R. Kimwarer and its tributaries form dendritic pattern, R. Yathine forms trellised pattern. ✓✓
• There are water holes, dams, pond. ✓✓
• Most rivers flow northeastwards. ✓
• Most of the rivers are originating from Keiyo escarpment. ✓

(ii) Citing evidence from the map, explain three economic activities carried out in the area covered by the map

Economic activity and  Evidence

Transportation ✓ | Roads / railway line ✓
Trading ✓ | Shops ✓
Wattle cultivation ✓ | Wattle plantation ✓
Milling / Lumbering ✓ | Saw mills / mills ✓
Forestry / Processing ✓ | Forest / forest center ✓
Communication ✓ | Post office ✓

7. Use the map of Africa to answer questions

(a) (i) The ocean current marked J

• - (warm) Mozambique ✓ / Agulhas

(ii) The climatic region marked H

• - savanna ✓ / Tropical continental / Sudan type

(b) State the characteristics of the climatic region marked G

• • The temperatures range ~~is~~ between 21°C in summer and 10°C in winter. / Summers are warm/hot, winters are cool/mild. ✓
  • The mean annual temperature range is between 8°C and 11°C. ✓ / moderate
  • Moderate rainfall / 500 mm to 900 mm. ✓
  • Rainfall ~~s~~ mainly falls in winter. ✓
  • Onshore / Offshore westerlies blow in winter causing cyclonic rainfall ~~cool and wet~~. ✓
  • Trade winds are offshore during summer / ~~hot and dry.~~ Summers are dry. ✓
  • The area experiences four distinct seasons / spring, autumn, summer and winter. ✓
  • Summers have cloudless skies. / Summers have low humidity. ✓
  • The western side of the climatic region receives more rain but it decreases inland. ✓
• Has long sunshine duration in summer.
• Experiences foggy conditions along the coast during winter.
• It experiences cold and hot local winds.

7. (c) Explain two ways in which the configuration of the coastline influences climate.

• • Irregular / indented coastline has more land area coming into contact with water which maximizes the effect of local wind. Thereby lowering / raising temperatures during the day / night. ✓✓
  • Irregular / indented coastline receives more rainfall because prevailing winds blow onshore carrying moisture inland. ✓✓
  • Straight / regular coastline receives less rainfall as prevailing winds blow parallel to the coast. ✓✓
  • Straight / regular coastline has less land area coming into contact with water which minimizes the effect of local wind ~~thereby rising~~ raising / lowering temperatures during the day / night. ✓✓

(d) Explain how equatorial vegetation is adapted to the climatic conditions

• - Trees have tall / straight trunks to compete for sunlight. ✓✓
• - Trees have broad drip tipped leaves to get rid of excess water due to high rainfall. ~~from the plant.~~ ✓✓
• - Tree trunks have smooth barks with few branches to reduce the amount of water retained due to high rainfall. ✓✓
• - Trees are evergreen because of high rainfall throughout the year. ✓✓
• - The climbers rise to the top canopies to receive sunshine. ✓✓
• - Most trees are hardwood because of constant high rainfall and high temperatures. ✓✓

(e) State four ~~possible~~ pieces of evidence ~~of the~~ for effects of climate change

• Recurrent heat waves in some parts of the world. ✓
• Melting of polar glaciers. ✓
• Receding of ice-cap on Mt. Kilimanjaro / Mt. Kenya / disappearance on Mt. Ruwenzori. ✓
• Increase of rainfall that causes flooding / change in rainfall patterns. ✓
• Disruption of seasons. ✓
• Abnormal plant growth. ✓
• Rise in sea level. ✓

(f) (i) State two objectives of the study

• To find out the factors that favoured the siting of the weather station. ✓
• To find out the instruments found in the weather station. ✓
• To find out how the elements of weather are measured / recorded. ✓
• To find out the significance of data recorded.

(ii) Give four activities that you would undertake in preparation for the study

• • Seeking permission from relevant authority. ✓
  • Preparing a work schedule. ✓
  • Selecting suitable methods of data collection. ✓
  • Undertaking a pre-visit / reconnaissance ✓
  • Forming groups. ✓
  • Formulating objectives / hypothesis
  • Obtaining a route map. ✓
  • conducting literature review
  • Gathering necessary equipment/tools

8. (a) (i) Name two agents of weathering

• Plants ✓
• Animals ✓
• Water / Ice ✓
• Heat ✓
• Air / Gases ✓

(ii) State four types of mechanical weathering

• Block disintegration / Separation
• Exfoliation (Onion peeling / spalling / spheroidal)
• Freezing and thawing / Frost action
• Crystal growth / Crystallization
• Slaking (Wetting and drying)
• Pressure release (Unloading / sheeting)
• Granular disintegration

(b) Describe the process of carbonation

• • Rain water dissolves carbon dioxide from the atmosphere to form weak carbonic acid.
  • The acidic rain water falls on jointed limestone / calcareous rocks.
  • This reaction forms calcium bicarbonate which is soluble / easily disintegrates.
  • The limestone rock gradually wears away

c) (i) Give three pieces of evidence of soil creep

• • Bending of fences / tree trunks / poles / railway lines.
  • Formation of mounds of soil behind walls / base of the slope.
  • Tilting of walls.
  • Scarp / slope retreat.
  • Soil forms terracettes / stepped / ribbed patterns.
  • Cracked road
  • Existence of bare rock / exposed upper slope.
  • Presence of overhanging banks above roads / rivers.
  • Rock outcrop arching downhill.

(ii) State four factors responsible for rapid mass wasting.

• • Scarcity / absence of vegetation
  • Earth movements / earth quakes.
  • Unconsolidated / loose materials.
  • Steep slopes.
  • High rainfall / intermittent supply of water / sporadic downpour.
  • Raising temperatures of glaciated highlands.
  • Human activities such as quarrying / mining / road construction.

d) Effects of Weathering on the Environment:

• Offers beautiful sceneries for tourist attraction. ✓✓
• Breaks up rocks making mining / quarrying easy. ✓✓
• Leads to formation of minerals (bauxite, aluminium). ✓✓
• Forms the initial stage in the soil forming process. ✓✓
• Weakens rock causing instability in road cuttings. ✓✓
• Accelerates soil erosion. ✓✓

9 (a) (i) Explain the term lake.

• A body of water contained within a crustal basin or hollow / an accumulation of water in a depression or basin.

(ii) Identify three factors that determine the size of a lake -Depth / size of hollow. -Amount of incoming water. 

-Amount of water lost through evaporation / seepage through rocks / outflow / Human activities

-Rate of siltation

(b) (i) Apart from crustal warping, give four processes that lead to formation of lakes.

• Faulting
• Folding
• Vulcanicity
• Glaciation
• Deposition
• Solution
• Erosion
• Human activities
• Falling meteorites
• Mass wasting

(ii) State two characteristics of lakes formed through crustal warping

• They are shallow.
• They are large / wide.
• They are formed between two raised land masses.
• They are irregular.
• Most of the lakes have fresh water.

c) With the aid of well labelled diagrams, describe how an ox-bow lake is formed.

• A river at flood plain stage begins to meander
• Intense lateral erosion and undercutting caused by active water currents takes place on its outer (concave) bank while deposition takes place in the inner (convex) bank.
• Due to lateral erosion, there is a reduction of the neck between the bends.
• Continued erosion on the outer bank and deposition in the inner bank makes the meanders to grow outwards.
• The neck of the land between the bends is eventually worn away.
• The two concave banks join causing the river to form a straight channel
• Alluvial deposition on the inner bank seals off the meander and cuts it off from the river
• The abandoned meander forms an ox-bow lake

• It helped to create order during the field study.
• It enabled the students to collect the correct data.
• It enabled all students to participate in the field study.
• It reduced congestion / overcrowding.
• It enabled the students to effectively accomplish their tasks.
• For effective time management.

(ii) Identify three methods of data recording that the students used.

• Photographing.
• Field sketching.
• Notes taking.
• Video taking / Filming
• Filling in questionnaire

10 a (i) Differentiate between porous and pervious rocks.

• Porous rocks have pores / air spaces that allow water to pass through while pervious rocks have cracks / joints through which water infiltrates.

(ii) Explain two ways through which precipitation influences ground water.

• Heavy downpour saturates the soil thus reduces rate of infiltration.
• Light showers that fall over a long period infiltrates more than heavy downpour.
• Very little rainfall merely wets the surface with little / no infiltration.
• High rainfall leads to high rate of infiltration.

(b) State three characteristics of a Karst landscape

• There are numerous solution depressions and residual hills.
• Surface drainage is intermittent or absent.
• There are many steep sided dry valleys.
• Presence of bare, rugged rocks surface / has scanty vegetation.
• Presence of a subterranean network of caverns and water courses.
• Has thin soils.
• The rocks are predominantly limestone / chalk / dolomite.
• Has rugged surface

(c) Explain three ways in which a Karst scenery influences human activities.

• Karst landscapes form beautiful features which attract tourists.
• Limestone landscapes discourage settlement / agriculture due to their ruggedness.
• Solution lakes provide sources of water for domestic / agricultural / industrial use
• Limestone is used as a raw material in iron and steel industry / cement manufacturing.
• The rugged terrain in limestone areas makes it difficult to construct transport lines.
• Limestone rocks are used in building and construction.
• Absence of surface water / vegetation / thin soils discourage agriculture / settlements.

d (i) Describe how the following features are formed I. Swallow hole

• Rainwater dissolves CO2​ from the atmosphere to form weak carbonic acid.
• The acid falls on limestone landscape.
• The rainwater reacts with calcium carbonate to form calcium bicarbonate which is soluble.
• The solution dissolves rock minerals widening the joints.
• This widens the joints.
• Continued solution process deepens the joints.
• The deepening and widening forms a vertical shaft / tunnel called a swallow hole.

II. Stalactites

• Drops of water containing calcium bicarbonate seep through crevices and joints of limestone rocks.
• Evaporation takes place because it is warm inside the cave.
• The drops are deposited after evaporation / release of carbon dioxide from the water.
• The drops of calcium bicarbonate then crystallise repeatedly to form hanging finger like projections / pillars on the roof of the cave.
• The hanging fingerlike pillars are called stalactites.

(ii) Apart from stalactites and swallow holes, name two underground features in a Karst scenery

• Stalagmites
• Limestone pillar / column
• Caves / caverns
• Underground / Subterranean streams / rivers