Tectonic Hazards: Earthquakes & Volcanoes — GCSE Geography Revision

Topic has curated content entry with explanation, mistakes, and worked example. [auto-gate:promote; score=75.25]

What is Tectonic Hazards: Earthquakes & Volcanoes?

Tectonic hazards are caused by the movement of the Earth's tectonic plates. Earthquakes occur when pressure is suddenly released at a plate margin, sending out seismic waves. Volcanoes are formed where magma from the mantle erupts onto the Earth's surface, most commonly at constructive and destructive plate margins. The characteristics of these hazards, such as an earthquake's magnitude or a volcano's eruption style, are determined by the specific type of plate boundary.

Board notes: Fundamental to all GCSE Geography specifications (AQA, Edexcel, OCR). Students must know the different plate margins (constructive, destructive, conservative, collision) and be able to link them to specific hazards and landforms.

Worked example

Common mistakes

• 1Confusing the focus and the epicentre of an earthquake. The focus is the point deep within the Earth's crust where the earthquake originates, while the epicentre is the point on the surface directly above the focus.
• 2Thinking all volcanoes are explosive, cone-shaped mountains. Shield volcanoes, found at constructive plate margins, have gentle slopes and produce runny, non-explosive lava flows.
• 3Assuming the biggest earthquakes always cause the most deaths. The impact of an earthquake is heavily influenced by factors like building quality, population density, time of day, and the effectiveness of emergency services, not just its magnitude on the Richter scale.

Tectonic Hazards: Earthquakes & Volcanoes exam questions

Exam-style questions for Tectonic Hazards: Earthquakes & Volcanoes with mark-scheme style solutions and timing practice. Aligned to AQA, Edexcel and OCR specifications.

Frequently asked questions

• Where do most earthquakes and volcanoes happen?

  The vast majority of tectonic hazards occur in narrow bands along the Earth's plate boundaries. The most famous of these is the Pacific Ring of Fire, which is a zone of intense earthquake and volcanic activity surrounding the Pacific Ocean.

• What is the difference between a primary and secondary effect of a tectonic hazard?

  Primary effects are the direct results of the event, such as buildings collapsing during an earthquake or lava flows from a volcano. Secondary effects are the knock-on consequences, like tsunamis, landslides, fires, or disease outbreaks that happen in the hours, days, and weeks after the initial event.