Plate Tectonics and Earthquakes

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Questions and Answers

What technique did Yacouba Sawadogo develop to combat desertification?

Crop Rotation

Terracing

Zai (correct)

Hydroponics

Which organization funded the Africa's Green Wall initiative?

International Monetary Fund

NATO

World Health Organization

United Nations (correct)

By 2050, what is the projected population of Africa?

2 billion

1.5 billion

2.4 billion (correct)

3 billion

What is a challenge posed by high population density in Africa?

Limited job opportunities Signup and view all the answers

What is the average number of children per woman in Africa?

4.7 Signup and view all the answers

What impact does urbanization have on Africa?

Rapid increase in urban population Signup and view all the answers

Which country has the highest birth rate in Africa?

Niger Signup and view all the answers

What was the financial cost of the Africa's Green Wall project?

$8 billion Signup and view all the answers

What does HDI measure in a country?

Income, education, and health Signup and view all the answers

Which is a negative impact of the colonial period on Africa's economy?

Delayed economic development due to competition Signup and view all the answers

What characterizes a savanna biome in Africa?

A mix of wet and dry seasons Signup and view all the answers

What is a significant cause of desertification in the Sahel region?

Overgrazing by livestock Signup and view all the answers

Which biomes are present in Africa?

Tropical rainforest, Deciduous woodland, and Tundra Signup and view all the answers

What role do trade winds play in Africa's climate?

They create rainfall by causing warm air to rise Signup and view all the answers

What is a primary reason for Africa's underdevelopment despite its natural resources?

Poor management and governance Signup and view all the answers

The Kalahari Desert is located in which part of Africa?

Southern Africa Signup and view all the answers

What phenomenon occurs when friction is overcome between tectonic plates?

A severe earthquake Signup and view all the answers

What is the primary cause of tectonic plate movement according to the convection current theory?

Convection currents in the mantle Signup and view all the answers

What term is used to describe the area directly above the earthquake's focus?

Epicenter Signup and view all the answers

Which of the following characteristics is associated with the Nepal earthquake of 2015?

Magnitude of 7.8 Signup and view all the answers

What allows for lower fatalities in high-income countries during earthquakes?

Strict building codes and preparedness Signup and view all the answers

What are pyroclastic flows primarily composed of?

Fast-moving hot lava, dangerous gases, and ash Signup and view all the answers

What is a common method to manage risks for people living in earthquake zones?

Drop, cover, and hold on technique Signup and view all the answers

What is a volcanic bomb?

Solidified lumps of molten rock Signup and view all the answers

Where are glaciers predominantly located on Earth?

In Antarctica and Greenland Signup and view all the answers

What is a key characteristic of regions where glaciers form?

Temperatures near freezing and significant winter snowfall Signup and view all the answers

What type of glacier is characterized by moving down slopes through valleys?

Alpine glaciers Signup and view all the answers

During an Ice Age, what percentage of the Earth's land surface was covered by ice?

30% Signup and view all the answers

What process leads to the formation of glacial ice?

Accumulation and compression of snow over time Signup and view all the answers

What happens when ablation exceeds accumulation in a glacier?

The glacier retreats Signup and view all the answers

What is the term for the end part of a glacier where water is released?

Snout Signup and view all the answers

Which process is NOT a function of glacial movement?

Combustion Signup and view all the answers

Which of the following statements accurately describes Ethiopia's geographical challenges?

The landlocked nature of Ethiopia complicates transportation of goods. Signup and view all the answers

What is one key reason for the prevalence of slums in Ethiopia?

Rapid urbanization leading to inadequate housing. Signup and view all the answers

How has the railway project funded by Chinese banks benefited Ethiopia?

It has improved trade efficiency and reduced transport times. Signup and view all the answers

What percentage of Africa's imports does China provide?

21% Signup and view all the answers

Which of the following highlights a potential risk associated with Chinese investment in Africa?

African countries could become reliant on foreign investment, leading to debt traps. Signup and view all the answers

What large-scale initiative is China undertaking worldwide that includes investments in Africa?

Belt and Road Initiative Signup and view all the answers

What is one major characteristic of life in slums, particularly in Ethiopia?

Limited access to sanitation and high disease rates. Signup and view all the answers

Who primarily benefits from Africa's trading relationship with China?

China benefits more due to its export levels being higher than imports. Signup and view all the answers

Study Notes

Plate Tectonics

Severe earthquakes occur when friction between tectonic plates is overcome.
The San Andreas Fault in California is an example of a plate boundary where earthquakes occur.
Two theories explain plate movement:
- Convection currents in the Earth's mantle, driven by internal heat, cause plates to move.
- Gravity pulls heavier, older parts of plates downward, causing them to move (Slab Pull/Ridge Push).

Earthquakes

Earthquakes are sudden and violent movements of the Earth's surface.
They occur when tectonic plates slip past each other at fault lines.
The focus is the point where seismic waves originate, while the epicenter is directly above the focus on the surface.
Seismic waves are measured by a seismograph, with magnitudes ranging from 0 to 10.
The 2015 Nepal earthquake had a magnitude of 7.8, causing chaos in the region.

Earthquake Risk Management

High-income countries have lower earthquake-related death tolls due to:
- Strict building codes and safer construction materials.
- Earthquake-resistant buildings.
- Controlled urbanization.
- Better preparedness and education among citizens.

Volcanoes

Volcanoes are openings in the Earth's lithosphere where magma rises to the surface.
Volcanic eruptions release:
- Liquid lava flows.
- Volcanic bombs (solidified molten rock).
- Hot ash and dust.
- Steam and gas.
- Fast-moving, dangerous pyroclastic flows.

Human Development

The Human Development Index (HDI) measures a country's development levels using income, education, and health indicators.

Africa

Africa faces challenges like:
- Tribal conflicts, resulting in violence and displacement.
- Poverty, despite abundant natural resources.
- A widening gap between the rich and the poor.
- Slow economic development, attributed to colonialism.
Africa also offers:
- Vast deserts, rainforests, and savannas.
- Abundant natural resources, exported as raw materials.

African Climate Biomes

Africa has diverse climate biomes with different vegetation, soil, and wildlife:
- Very desert/semi-desert areas with little rain.
- Savannas with wet and dry seasons.
- Rainforests with year-round rainfall.
Trade winds influence climate patterns:
- Warm air rises near the equator, resulting in low pressure and rainfall.
- As air moves northward, it cools, decreases in pressure, and results in less rainfall.

The Sahel

The Sahel is a region in North Africa vulnerable to drought, leading to:
- Crop failure.
- Water scarcity.
- Frequent famines.
- Overgrazing, which depletes vegetation and exacerbates desertification.
Yacouba Sawadogo, a peasant farmer, developed a technique called Zai to combat desertification.
Africa's Green Wall is a large-scale reforestation project aiming to restore degraded land in the Sahel.

Population Change in Africa

Africa's population is estimated to be 1.5 billion, with a high density and a young population.
The high birth rate is a contributing factor to economic challenges, including:
- Poverty.
- Hunger.
- Limited job opportunities.
- Fewer adult voices.
However, the young population also presents opportunities:
- Potential for innovation and economic growth.
- A large, cheap labor force.

Urbanization in Africa

Africa experiences the fastest urbanization rate, leading to:
- Poverty and slums.
- Challenges in providing services like hygiene and water.
Solutions include:
- Low-cost housing initiatives.
- Infrastructure development, such as railways.
- Attracting multinational companies to create jobs.

China and Africa

China has invested heavily in infrastructure development in Africa, aiming to:
- Improve access to ports and trade routes.
- Increase trade between China and Africa.
- Extract natural resources from Africa.
While China's investment brings potential benefits, concerns include:
- Debt traps for African countries.
- Exploitation of African labor.
- China's dominance in trade with Africa.

Glaciers

Glaciers are large masses of ice formed over centuries by compressed snowfall.
They are found mostly in Antarctica and Greenland.
Glaciers contain 75% of the world's freshwater and cover 10% of the Earth's land area.
Glaciologists study glacier changes and their impact on landscapes.
Two main types of glaciers exist:
- Alpine glaciers, found on mountain slopes.
- Continental ice sheets, covering larger areas.

Ice Ages

Ice ages occur when global temperatures are cold enough to form glaciers and ice sheets.
During the last ice age, the Earth was about 5°C colder than today.
Ice covered approximately 30% of Earth's land surface during that period.

Formation and Movement of Glaciers

Glaciers form in cold, snowy regions above the snowline.
Snow accumulates and compresses under its own weight, transforming into ice.
Gravity causes glaciers to flow downslope.
Glaciers advance when accumulation exceeds ablation (melting and loss).
Glaciers retreat when ablation exceeds accumulation.

Glacial Landscapes

Glaciers sculpt landscapes through weathering, erosion, transportation, and deposition.
They carve valleys, form U-shaped valleys, create moraines, and deposit sediment.

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Description

This quiz covers key concepts in plate tectonics and earthquake mechanics, including the causes of earthquakes, the role of tectonic plates, and risk management strategies. Test your knowledge on seismic waves, fault lines, and significant earthquake events.