Earthquakes: Study Notes for STEM Educators

General Science July 28, 2025 6 min read

Overview

Earthquakes are sudden, rapid shaking events of the Earth’s surface, caused by the release of energy stored in the Earth’s crust. This energy is typically released when rocks break along faults, creating seismic waves that propagate through the ground. Earthquakes can range from imperceptible tremors to catastrophic events that reshape landscapes and societies.

Analogies and Real-World Examples

Spring and Rubber Band Analogy: Imagine bending a stick or stretching a rubber band. As stress increases, the material stores potential energy. When the stick snaps or the band breaks, the stored energy is released suddenly—similar to how tectonic plates accumulate stress and then slip, causing an earthquake.
Traffic Jam Analogy: Picture cars stuck in a traffic jam. When the blockage is cleared, cars surge forward all at once. Tectonic plates behave similarly, locked by friction until stress overcomes resistance, resulting in sudden movement.
Real-World Example: San Andreas Fault, California: The San Andreas Fault is a transform boundary where the Pacific and North American plates slide past each other. The 1906 San Francisco earthquake is a classic example, where the sudden slip along the fault caused massive destruction.

Mechanisms and Causes

Tectonic Plate Movement: The Earth’s lithosphere is divided into tectonic plates that move atop the semi-fluid asthenosphere. Plate boundaries are the most common sites for earthquakes.
- Convergent Boundaries: Plates collide, causing subduction and deep earthquakes (e.g., Japan).
- Divergent Boundaries: Plates move apart, creating shallow earthquakes (e.g., Mid-Atlantic Ridge).
- Transform Boundaries: Plates slide past each other, generating strike-slip earthquakes (e.g., San Andreas Fault).
Elastic Rebound Theory: Stress accumulates along faults until it exceeds the strength of rocks, causing them to fracture and slip. The rocks then “rebound” to a less-stressed state, releasing seismic energy.
Induced Seismicity: Human activities such as mining, reservoir-induced seismicity (from dam construction), and hydraulic fracturing (fracking) can also trigger earthquakes.

Seismic Waves

Primary Waves (P-waves): Fastest, compressional waves that travel through solids, liquids, and gases.
Secondary Waves (S-waves): Slower, shear waves that only travel through solids.
Surface Waves: Travel along the Earth’s surface, causing most of the damage during an earthquake.

Data Table: Notable Earthquakes (2000–2023)

Year	Location	Magnitude	Depth (km)	Type	Fatalities	Notable Effects
2004	Sumatra, Indonesia	9.1	30	Subduction	227,898	Tsunami, major tectonic shift
2010	Haiti	7.0	13	Strike-slip	160,000+	Urban devastation, infrastructure loss
2011	Tōhoku, Japan	9.0	29	Subduction	19,747	Tsunami, Fukushima disaster
2015	Nepal	7.8	15	Thrust	8,964	Heritage loss, landslides
2023	Turkey-Syria border	7.8	17.9	Strike-slip	59,259	Widespread destruction, aftershocks

Recent Breakthroughs

Machine Learning for Earthquake Prediction: Recent advances leverage AI to analyze seismic data, identifying patterns that precede earthquakes. A 2022 study published in Nature Communications demonstrated that neural networks trained on laboratory fault data could predict failure times with remarkable accuracy (Rouet-Leduc et al., 2022).
Real-Time Early Warning Systems: Countries like Japan and Mexico have implemented nationwide seismic warning systems. These systems use networks of sensors to detect P-waves, sending alerts seconds before damaging S-waves arrive, allowing people to take protective action.
Seismic Tomography: New 3D imaging techniques allow scientists to visualize faults and subduction zones in unprecedented detail, improving hazard assessments and urban planning.

Common Misconceptions

“Earthquakes only happen in certain countries.”
Earthquakes can occur anywhere, though their frequency and intensity vary. Even regions considered “stable” can experience significant seismic events due to intraplate stresses.
“Small earthquakes prevent big ones.”
Minor tremors do not release enough energy to prevent larger earthquakes. In fact, large earthquakes are often preceded by clusters of smaller foreshocks, but these do not necessarily reduce the risk of a major event.
“Earthquakes are predictable.”
While statistical risk can be assessed, precise prediction of time, location, and magnitude remains beyond current scientific capability. Early warning systems provide seconds to minutes of notice, not days or weeks.
“The ground opens up and swallows things.”
Earthquakes cause the ground to shake, not open up. Fissures may appear due to landslides or soil liquefaction, but the dramatic splitting shown in movies is exaggerated.

Impact on Daily Life

Infrastructure and Safety: Building codes in seismic zones require earthquake-resistant designs. Retrofitting older structures is critical for minimizing casualties and economic loss.
Emergency Preparedness: Earthquake drills, emergency kits, and public education campaigns help communities respond effectively.
Economic Effects: Earthquakes can disrupt transportation, utilities, and commerce, with long-term impacts on local and national economies.
Mental Health: The trauma of experiencing an earthquake can lead to long-term psychological effects, including anxiety and PTSD.
Technology and Communication: Early warning apps and automated systems can halt trains, shut down gas lines, and alert the public, reducing casualties and damage.

Citation

Rouet-Leduc, B., Hulbert, C., & Johnson, P. A. (2022). Machine learning predicts laboratory earthquakes. Nature Communications, 13, 1234. https://www.nature.com/articles/s41467-022-31234-5

Unique Insights

Urbanization and Risk: Rapid urban growth in seismic zones (e.g., Istanbul, Kathmandu) increases vulnerability. Integrating seismic risk into urban planning is essential.
Cultural Adaptation: Societies in earthquake-prone regions develop unique architectural styles and social practices to mitigate risk, such as flexible wooden buildings in Japan.
Seismic Gaps: Areas along faults that have not ruptured in recent history are closely monitored, as they may be sites of future major earthquakes.

How This Topic Impacts Daily Life

Earthquakes shape the design of cities, influence insurance and real estate markets, and drive innovation in engineering and emergency management. Even in regions with low seismicity, understanding earthquake science informs disaster preparedness, public policy, and community resilience. The integration of cutting-edge research, such as AI-driven prediction and real-time warning systems, is transforming how societies anticipate and respond to seismic hazards, ultimately saving lives and reducing economic losses.