Earthquakes

“Earthquakes: Breaking Down the Science and Equipping You with Life-Saving Safety Techniques”

These movements occur along faults or cracks in the Earth’s crust, often concentrated at plate boundaries. When plate movements cause stress to build up and break, rocks are released, releasing energy in the form of seismic waves. Earthquakes can also be caused by volcanic activity, where the movement of magma within the Earth creates vibrations, especially during eruptions. Human activities such as mining, large-scale reservoir construction, and hydraulic fracturing also cause earthquakes, often called anthropogenic or human-induced earthquakes. While most natural earthquakes are relatively small and barely felt, some can be devastating, causing widespread destruction of buildings, and infrastructure, landslides, tsunamis, fires, and significant loss of life. 

What is an Earthquake?

A Ground shaking is a shaking of the Earth’s surface caused by a sudden release of energy in the planet’s lithosphere. This energy release creates seismic waves, which are responsible for ground movement. Plate movements occur naturally and as a result of human activities, such as mining or reservoir-induced seismicity.

Causes of earthquakes.

Tectonic plate movement: The Earth’s crust is divided into tectonic plates. These plates are constantly moving, although very slowly. Most earthquakes occur when these plates collide, slide past each other, or move apart.

Example: The San Andreas Fault in California is a well-known boundary between two tectonic plates, making this region prone to earthquakes.

2. Volcanic activity: Some Ground shakings are caused by volcanic activity. When magma moves beneath the Earth’s surface, it can cause vibrations.

Example: Earthquakes around Mount St. Helens in Washington state are associated with volcanic activity.

Human activity: Large-scale human projects such as the construction of dams, mining, and drilling can also cause seismic events.

Example: The 2008 Sichuan earthquake in China was partly linked to the construction of the Zipingpu Dam.

How are earthquakes measured?

• Ground shaking is measured using seismometers, which record seismic waves. Intensity and magnitude are determined by:

Types of Earthquakes

1. Tectonic Earthquakes: Caused by the movement of tectonic plates.
2. Volcanic Earthquakes: Linked to volcanic eruptions.
3. Collapse Earthquakes: Occur due to the collapse of underground structures, like mines.
4. Explosion Earthquakes: Resulting from nuclear tests or explosions.

Highest and Lowest Recorded Earthquakes

Highest Recorded Earthquake

• Name: The Great Chilean Earthquake
• Date: May 22, 1960
• Location: Valdivia, Chile
• Magnitude: 9.5
• Duration: Approximately 10 minutes
• Impact: Massive destruction with tsunamis reaching across the Pacific, affecting Japan and the Philippines. Over 5,000 people lost their lives.
• Lowest recorded Shocks are typically around 1.0 Mw and occur often around the world.
  • Microearthquakes in geothermal areas, like California’s Imperial Valley, typically go unreported by humans.
  Famous Shocks throughout History
  1. Indian Ocean Earthquake and Tsunami (2004) • December 26, 2004

• Location: Off the west coast of northern Sumatra, Indonesia • Magnitude: 9.1-9.3 • Impact: A destructive tsunami killed over 230,000 people in 14 nations.
  2. Shaanxi Earthquake (1556). • Date: January 23, 1556
• • Location: Shaanxi, China • Magnitude: Around 8.0 • Impact: The worst Shocks in history, resulting in around 830,000 deaths.
  Kashmir Earthquake (2005) • Date: October 8, 2005, • Location: Muzaffarabad, Pakistan-administered Kashmir.
  • Magnitude: 7.6 • Impact: Over 85,000 dead, severe devastation in northern Pakistan and India.
•  Impact: Over 85,000 deaths, with extensive destruction across northern Pakistan and India.

4. Japan’s Great East Earthquake (2011)

Date: March 11, 2011

Location: Near the Tōhoku region, Japan

Magnitude: 9.1

Impact: Triggered a catastrophic tsunami and the Fukushima nuclear disaster, causing nearly 20,000 deaths.

Science Behind Ground shaking
Seismologists study Earth vibrations in order to forecast their recurrence and understand their patterns. Here’s how earthquakes happen.
1. Stress accumulation: Friction can cause tectonic plates to become locked over time. As they move forward, they get more stressed.

Most Ground quake-Affected Areas
Because of their placement near tectonic plate borders, some areas are particularly susceptible to earthquakes. This includes:
1. Japan, Indonesia, and Chile are part of the Ring of Fire, which covers the Pacific Ocean.
2. Himalayan Region: Frequent earthquakes are a result of the Indian and Eurasian plates colliding in this area.
3. California, USA: With the San Andreas Fault, the state routinely sees moderate to major earthquakes.

Steps To Stay Safe During an Earth vibrations, preparation and awareness are critical. Here’s how you can be safe:
Before a Ground quakes
1. Identify secure areas in your house, such as below solid tables or against interior walls.
2. Fasten bulky equipment and furnishings to the wall. Have an emergency kit ready with water, food, flashlights, batteries, and first aid supplies.

Develop an emergency communications plan with your family.

During an earthquake

• Indoors: Lie on the ground, hide under a sturdy object, and hold on. Stay away from windows and heavy objects.
• Outdoors: Move to an open area away from buildings, trees, and power lines.
• Driving: Stop the vehicle in a clear area and stay inside until the shaking stops.
• After the Ground quakes
• Check for injuries and help others if needed.
• Avoid entering damaged buildings.
• Be prepared for aftershocks, which may occur hours or days after the main earthquake.
• Prevention and Preparation
• Although we cannot prevent earthquakes, there are ways to reduce their impact:

• Quake-resistant buildings: Engineering advancements make structures more resistant to earthquakes.
• Mobile apps: Apps can alert users about Ground quakes and provide safety tips.
• Role of governments and NGOs
• Governments and non-governmental organizations (NGOs) play a vital role in managing earthquake disasters:
• 1. Prevention: Enforce building codes and urban planning.
• 2. Response: Coordinating rescue operations and providing aid.
• 3. Rehabilitation: Helping affected communities rebuild homes and infrastructure.

A wake-up call for humanity

• Quakes remind us of the Earth’s immense power and our vulnerability. Although we cannot stop them, we can prepare to reduce their impact.
• Understanding their causes, history, and science better prepares us to cope with these natural phenomena.
• Let us remember the countless lives lost to earthquakes and work towards safer communities. Whether through education, technology, or disaster management, every step counts in making our world more resilient to this unpredictable force of nature.
• By fostering a culture of preparedness and awareness, we can empower individuals and communities to respond effectively in the face of such disasters.
• Collaboration among governments, scientists, and citizens is crucial to developing innovative solutions that enhance our readiness and recovery efforts.