Geo

• Faults

  Cracks in the earth where sections of a plate (or two plates) are moving in different directions
• Faults

  • Caused by plates bumping and sliding
  • More common near the edges of the plates
• Why earthquakes happen

  1. Rocks underground suddenly break along a fault

  2. Sudden release of energy causes seismic waves that make the ground shake

  3. Blocks of rock or plates rub against each other, stick, then break due to built up pressure

  4. After the earthquake, the plate or blocks of rock start moving and continue until they get stuck again
• Focus

  The spot underground where the rock breaks
• Epicenter

  The place right above the focus (on top of the ground)
• Most earthquakes and volcanic eruptions occur in specific areas, such as along plate boundaries
• Natural Increase Rate (NIR)

  When birth rates exceed death rates
• Birth Rate


  Live births per 1000 people, per year
• Death Rate

  Deaths per 1000 people, per year
• Fertility Rate


  Average number of children a woman has during her lifetime. If FR > 2.1 (replacement level), there will be population growth
• Infant Mortality Rate


  Number of children under the age of 1 who die, per 1000 live births, per year
• Life Expectancy


  Average number of years at birth a person is expected to live
• Factors affecting Fertility

  • Tradition
  • Education
  • Religion
  • Age structure
  • Economics
  • Female Status
  • Government Policy
• Factors affecting Mortality


  • Poverty
  • Medical Infrastructure
  • Economic Development
  • Ageing Population
  • HIV/AIDS
  • Non-Communicable Diseases
  • Injury Related Illnesses
  • Public Pensions/Healthcare
• Absolute Data


  Measured in millions
• Relative Data


  Measured in percentages
• Sex Ratio


  Number of males per 100 females
• Dependency Ratio


  Shows the relationship between people of working age, and those who are dependents
• Support Ratio


  Inverse of the dependency ratio
• Juvenility Index


  Proportion of younger people in a population
• Old Age Index


  Proportion of elderly people in a population
• Demographic Transition Model (DTM)

  Changes in Birth/Death Rates
• The DTM in LICs has happened differently to Europe, with much higher initial birth rates, much steeper fall in death rates (ignoring HIV/AIDS), and steep fall in fertility due to contraception access
• Advantages of DTM


  • Easy to understand
  • Universal concept can be applied to all countries
  • Flexible timescales
  • Allows comparisons to be made
• Criticisms of DTM


  • Original model did not contain a 5th stage, and can't predict when changes will occur for a country
  • Eurocentric, so assumes all countries will follow the way that Europe developed
  • Ignores regional differences within a country
  • Does not consider migration, government policies or war/disaster events impacting a population
  • Diseases such as HIV/AIDS can put the model in reverse
• Causes of Youthful Populations

  • High BR (lack of family planning and contraception, high infant mortality)
  • Migration
  • Tradition
  • Lack of care for old dependents leads to high DR amongst that age group
• Advantages of Youthful Populations

  • Lower DR, higher demand on country
  • IT literate and educated population
  • Large future market
• Issues with Youthful Populations

  • Abundance of future workers may result in unemployment
  • Cost of childcare and child benefit is high
  • Short term worker shortage
  • High healthcare costs
  • Spending diverted from other uses
• Solutions for Youthful Populations

  • Anti-natalist policies, reduced BR/IM
  • Privatised education/healthcare
  • Increased immigration of middle aged, restricted immigration
  • Removed child benefits
  • Greater care of old dependents, to reduce death rate in elderly
• Causes of Ageing Populations

  • Good medical care, diet, sanitation, water supply and hygiene
  • Emancipation of women
  • Increasing cost of children
  • Emigration of economically active
• Advantages of Ageing Populations


  • Valuable experience and expertise
  • Less money needs to be spent on schools and pre-/child medical care due to declining BR
  • Lower crime rates, less police needed
  • Elderly workers don't need maternity leave, more willing to work and loyal
• Issues with Ageing Populations

  • Elderly workers do not have IT skills, get sick easier, could retire at any time, unable to work manual jobs
  • Shortage of economically active workers
  • Reduced tax revenue for government; so reduced spending on education, healthcare, transport, policing...
  • High pension cost, and high cost of providing healthcare/care homes
  • Service reduction (sports facilities, schools) not used by older population
• Solutions for Ageing Populations

  • Pro-natalist policies
  • Increased immigration of economically active
  • Increase retirement age
  • Private pensions/healthcare
  • Increase taxes
• Development


  Improvements to the quality of life
• Factors affecting Development


  • Physical (land locked countries, small islands, tropical countries, rich in natural resources)
  • Economic Policies (encouragement of foreign investment, high savings rates, low spending, good government, law and order, lack of corruption)
  • Demography (fast progress through the DTM, high economic growth rates correlate with fast birth rate drop)
• Human Development Index


  4 variables (life exp at birth, mean schooling years at 25, expected schooling years, GNI pp) define development since it cannot be based on only one
• Infant Mortality has reduced globally from 46/1000 to 38/1000 in 10 years, and from around 150/1000 to 70 years in 100 years, due to better nutrition, health and sanitation improvements, housing improvements and health advancements directly for the neonatal period
• Life Expectancy has increased globally from 30 years in 1900 to 46 years in 1950 and 70 years in 2020, and the gap between HICs and LIC/MICs will reduce as increased life expectancy is the reward of economic and social development
• Food Security


  When all people at all times have access to sufficient, safe, nutritious and affordable food to maintain an active lifestyle
• Aspects of Food Security

  • Availability (sufficient food quantities available on a consistent basis)
  • Access (having enough land/money to obtain appropriate food for a nutritious diet)
  • Use (appropriate use of food using basic knowledge of nutrition, care and having adequate water/sanitation)