MOUNTAINSThey are types of landform, which

are characterized by high elevation. They are steeply above their surrounding to a narrow summit on top.

Compared to other landform, like hills they are much higher, taller and steeper.They are higher as much as 8000 meters,

Highest Mountain is the Mountain Everest – 8,850 meters tall.

• They are landform that strecthes above the surrounding land in a limited area, usually in the form of a peak.

• These forces locally rises in the surface of the earth’s crust by over 10,000 ft.

• It erode slowly through the action of rivers, weather conditions, and glaciers.

• High elevations on mountains are colder than at sea level, which affect the ecosystem of mountains with different elevation.

• Highest Mountain – Mount Everest – Himalayas. Whose summit – 8,849,868 m. Above sea level.

• Pic of Mt Everest

Mountains Range Country Feet

1. Everst Himalayas Nepal/Tibet 29,035

2. K2 (Mount Godwin Austen)

Karakoram Pakistan/China 28,250

3. Kangchenhjunga Himalayas Indian/ Nepal 28,169

4. Lhotse Himalayas Nepal/Tibet 27,940

5. Makalu Himalayas Nepal/Tibet 27,766

6. Cho Oyu Himalayas Nepal/Tibet 26,906

7. Dhaulagiri Himalayas Nepal 26,,795

8. Manaslu Himalayas Nepal 26,781

9. Nanga Parbat Himalayas Pakistan 26,660

10. Annapurna Himalayas Nepal 26,545

Varying climatic condition can be observed on the mountains due to their elevations or height. The conditions at the base of a very tall mountain differ from the topmost area.

The peak is colder and may eveb snow –covered .

There are less oxygen and less protection from the sun’s ray on top.

TYPES OF MOUNTAINS

BASED ON FORMATION1. volcanic2. dome3. erosional4. fault-block5. folded

VOLCANIC MOUNTAINS

Also known as volcanoes. They are formed due to volcanic eruptions. Due to

very high temperature inside the earth, the hot molten material called magma finds its way out on the earth’s surface.

Magma becomes lava once it goes out of the earth’s surface. When this lava erupts and piles up on the surface of the earth, it cools and solidifies to form a volcanic mountain.

Ignreous rocks are formed in this mountain. Examples are the Mount Fuji in Japan and Mount Erne in Europe.

Mount Fuji

DOME MOUNTAIN

It is built from the hot magman that rises from the mantle and uplifts the overlying sedimentary layer of the earth’s crust. Magma is not erupted in the process but cools down and hardens, forming the core of the mountain.

It is called dome mountain because its appearnce resembles a dome shape. Examples are the Navajo mountain in Utah and Adirondack Mountains in New York.

Pic of dome mt.

EROSIONAL MOUNTAINS

Water and wind may wear foundations of lands. These lands may be carried away.

Some lands may resist waer and wind and may remain in place.

These materials may resist erosion and will lead ton the formation of erosional mountains. Examples are the Pike’s Peak in Colorado, which is a large mass of granite that has resisted erosion for many years.

Pic of erosional mt.

FAULT-BLOCK MOUNTAINS

They are formed when blocks of rock materials slide along faults in the earth’s crust.

Fault-block mountains may be of two types:1. lifted – lifted has two steep sides2. tilted – has one steep side and a gentle sloping side. Example are Sierra Nevada Mt. And the Teton Range in North America.

Fault-block mt.

FOLD MOUNTAINS

These are the most common type of mountains. They are formed due to collision of two plates, pushing against each other.

Pushing against each other causes intense pressure causing folding of the earth’s crust.

The fold that descends on both sides is called anticline.

The fold that ascends from a common low point is called syncline. Examples are the Himalayas in Asia, Rocky Mountains in North America and the Alps in Europe.

Pic of Fold Mt.

WeatheringThe surface of the earth is

always changing due to the natural process – Weathering. It is a process which changes the physical and chemical properties of rocks and soil on the earth’s surface.

It is also the first step to soil formation.

breaking down of rocks, soil and minerals through theearth’s atmosphere , biota and water.

WEATHERING, SOIL AND MASS WASTING

Two types of Weathering:1. Physical or Mechanical Weathering2. Chemical Weathering

Physical /mechanicalWeathering – occurs when physical forces break rocks or soil into smaller pieces without changing the rock’s composition, which is cause by: 1. Frost wedging or water or ice – the mechanical break-up of rock is due to the expansions of freezing water in cracks.

2. Pressure (Stress) Release or heat – also known as unloading which occurs when overlying materials that cause stress to the underlying rocks are removed by erosion.

3. Salt Crystal Growth (Salt Crystallization) – the disintegration of rocks which is caused by salt solution that seep into cracks and joint in the rocks. The water component of the salt solution evaporates leaving salt crystals behind. When salt crystals are heated up, it expands exerting pressure on the rock which causes its breakdown.

4. Water (hydraulic )action – The disintegration of rocks is caused by water from powerful waves that moves rapidly into cracks in the rocks.

5. Thermal (Insolation) Stress – Rock expands when heated and contracts when cools. The outer layers of the rocks peel off in thin sheets because of the temperature changes which cause expansion and contraction of rock. It is an important mechanism in desserts, where there is a large temperature range, hot in the day and cold at night.

Chemical Weathering –is a weathering which causes change in the composition of rock due to different chemical reaction, like:

1. Cabonation – it occurs when water (rain) combines with carbon dioxide or an organic acid to form a weak cabonic acid. This acid reacts with calcium carbonate (limestones) present in the rock and forms calcium bicarbonates. Decrease temperature can speed up the chemical reaction because cold water holds more dissolved carbon dioxide gas. Therefore, carbonation is a significant feature of glacial weathering.

2. Hydrolysis – refers to the reaction between water ans silicate and carbon minerals present in rock.

3. Oxidation – it involves the reaction between oxygen (air or water) and metal (iron) present in rock.

BIOLOGICAL WEATHERING

Living organisms may contribute to mechanical or chemical weathering. Plants, animals and human can cause physical breakdown of rocks. The attachment if lichen and mosses to the rock surface can cause physical breakdown of rocks. Plant roots can cause physical breakdown weathering.

SOIL

It is the product of weathering of rocks., which is vital for the existence of life forms. It supports the growth of plants, which in turn supplies nutrients to other organisms in the ecosystem.

PEDOGENESIS – process of soil development, influenced by 4 interrelated factors.

1. Climate – greatest effect on soil formation. Temperature and moisture are the two imortant climate variables that have significant influence on soil formation.

2. Living Organisms – plays a significant role in various processes involved in pedogenesis suh as;

1. Organic matter accumulation2. Profile mixing3. Biogeochemicak nutrient cycling Decayed living matter adds humus or

nutrients to the soil.Plants and animals participate in the

biogeochemical cycle especially the carbon and nitrogen Cycle.

3. Parent material – refers to the unconsolidated rock and mineral materials from which the soil develops. The type of parent material determines which minerals are poresent in the soil. In residual soil the parent material is the bedrock while in the transported soil, the oparent material has been carried from elsewhere and deposited.

4. Topography – refers to the physical features of an area, which modifies the development of soil because of its effect on microclimate and drainage.

Topography – influence the runoff of water which can hinder soil formation because of constant erosion.

Microclimate – refers to the climate of the specific place which can affect the soil formation due to the relative warmth and moisture that influence the rate and degree of weathering.

CHARACTERISTICS OF SOIL

1. Texture – refers to the size distribution of the mineral particles found in soil. Particles are normally grouped into three:

1.1 sand1.2 silt1.3 claySandy Soil – has the biggest particles which is good for

aeration and drainage of the soil. It is an advantage for plants, it allows the water to drain easily which prevent root to rot problems. It is granular and consists of rocks and minerals that are very small. It is formed by the disintegration and weathering of rocks such as limestone, granite, quarts and shale.

It is easier to cultivate because of the organic material, moisture and nutrients. During spring season they warm very fast.

Silty Soil – it one of the most fertile soil. It is composed of minerals like quarts, and fine organic particles, has more nutrients than sandy soil. It is granular like sandy soil, but it offer better drainage. Hold more moisture which makes it much easier to work with.

Clay Soil – is rich in minerals content and very fine grain materials with very less air space which is responsible for its low drainage. It is heavy when wet, making it difficult to cultivate.

It can be formed into sedimentary rocks deposits after weathered, eroded and transported.

EROSION

Removal of soil sediment, regolith and rock fragments from the landscape.

Three processes involve in erosion:1. Detachment – revomal of particles from

surrounding materials due to physical, chemical and biological weathering. Different mechanism for the detachment are;1.1 Plucking – occurs when ice freezes onto the surface and cracks which causes fragmentation of the rocks.

2. Cavitation is caused by moving water with high velocity like high waterfalls. 3. Abrasion – is due to the excavation of surface particle by materials carried by the erosion agent.

2. Entrainment – process of particle lifting by the agent of erosion. The particles cohesive bondsweakened by weathering or forces created by erosion.

• 3.Transport – once a particle is entrained, transport can already occur through various mechanisms such as suspension, saltation, traction and solution.

A. Suspention- is where the particles are carried by the medium without touching the surface of thier origin.

B. Saltation- is where the particle moves from the surface to the medium in quick continuous repeated cycles.

C. Traction- which ocurs in all erosional mediums in characterized by the movement of particles by rolling, sliding, and shuffling along the aroded surface.

D. Solutions- is a transport mechanism that occurs only in aqueous environments.

• Deposition the process which ends erosion is known as deposition which occurs when the transported particles fall out of the transporting medium and settle on a surface.

Mass Movement or mass wasting is the geomorphic process by whitch soil and rock move downslope under the force of gravity.

Types of mass movement the various types of movement include creep, landslide, flows, topples, slump, falls and debris avalanche (figure 10.3).

1. Creep is the slow downhill movement of soil wherein the steeper the slope means faster creep.

2. Flow is characterized by mass movements of material containing a large amount of water.

3.landslide which also called landslip, is arapid movement of a large mass of earth and rocks down a hill or a mountainside.

4.Topples occurs when blocks of rock pivot and fall away from a slope.

5.Slump is the downward movement of a block of material along a curved surface.

6.Falls or rockfall occurs when rocks or rock fragments fall freely through the air.

7.Debris avalanche is a variety of very rapid to extremely rapid debris flow.