(#7-#11) For one natural hazard type: Earthquakes

#7 describe the characteristics of the hazard (Earthquakes)

• Seismic waves of energy that radiate from faults in all directions and involve violent shaking of the Earths oceanic and continential crust

• Small earthquakes occur constantly but are usually only detected by special equipment like seismographs

• Earthquakes are located along tectonic plate boundaries and countries such as Indonesia have experienced 199 major earthquakes in the last 10 years due to being located close to the boundaries

• Earthquakes are considered to be the deadliest natural hazard with having an average of 10,000 - 50,000 casualties per year

  • during the 21st century:

    • 2023 has nearly 67,000 deaths

    • 2025 having 607 deaths

#8 explain the cause/s of the hazard (Earthquakes)

• Seismic waves of energy that radiate from fault in all directions and involve violent shaking of the earths oceanic and continental crust

• Movement of tectonic plates

  • can become locked together by friction, causing stress to build up in earths crust

  • when stress becomes too great, the rocks suddenly break or slip along the fault

  • the break releases large amounts of energy in the form of seismic waves, which travel through the earth; causing the ground to shake

• Most occur along tectonic plate boundaries, especially transform, and convergent boundaries

#9 describe the spatial and temporal distribution of the hazard  (Earthquakes)

Spatial:

• Primarily concentrated along the plate boundaries specifically along transforming, converging/subducting plates

  • e.g Ring of Fire, Mid Atlantic Ridge with the exception of converging plates, Alpine (Alpide) Belt

Temporal:

• Hard to predict but follow a clustered temporal logic

• No seasonal pattern

• Aftershocks most predictable due to mainshock before hand

#10 explain how physical and/or human processes determine the spatial and temporal distribution of the hazard (Earthquakes)

Physical/Spatial:

• Concentrated along tectonic plate boundaries (Pacific Ring of Fire) and active fault lines where earths crust is moving and grinding

Human/Spatial:

• Concentrated directly around Industrial sites: specifically near deep waste water disposal wells, massive reservoirs/dams, geothermal projects, and deep mines (fracking)

Physical/Temporal:

• Governed by the stress-and-release cycle (elastic rebound).

• Stress builds up naturally over decades or centuries and releases suddenly, often followed by predictable clusters of aftershocks

Human/Temporal:

• Tied directly to operational schedules. Earthquakes happen during or shortly after periods of high-pressure fluid injection, mining excavations, or seasonal filling of heavy reservoirs

#11 compare the physical and human factors that explain why less developed countries are more vulnerable to the hazard (Earthquakes) than more developed countries

Physical:

• Both LEDCs and MEDCs sit on dangerous fault lines. However, LEDCs often have to expand to rugged, unstable physical terrain that is highly prone to secondary hazards like landslides and mudslides when shaken due to lacking geographic alternatives

Human:

• Infrastructure: MEDCs use advances seismic engineering while LEDCs rely on cheaper, unreinforced materials that collapse easily

• Preparedness: MEDCs have early-warning systems, heavily equipt emergency services, and public drill programs. LEDCs suffer from underfunded hospitals, lack of rescue gear, and weak emergency response

• Governance: LEDCs frequently struggle with rapid, unplanned urbanisation and a lac of building code enforcement due to limited resources or corruption

• Recovery: MEDCs recover quickly through insurance and government reserves. LEDCs often face long-term economic devastation and depend on slow international aid to rebuild