SCIENCE 11 - Different Hazards Cause by Geological Processes by Teacher Christine Junedee L. Corsiga

Summary

In this educational video, Teacher Christine from Pantucka National High School discusses various geological hazards, including earthquakes, volcanic eruptions, and landslides. She explains the causes, effects, and potential dangers of these phenomena, such as ground rupture, liquefaction, and tsunamis associated with earthquakes, and lava flows, ashfall, and lahars from volcanic activity. The video also covers the triggers for landslides and provides safety tips for these natural disasters, emphasizing the importance of preparedness and awareness.

Takeaways

• 🌏 Geological processes are events occurring at the Earth's surface, often due to natural forces like gravity and temperature changes.
• 🔍 Geohazards are the hazards associated with geological processes, which can cause loss of life, property damage, and environmental disruption.
• 🌋 Earthquakes are caused by the movement of rock materials below the surface, originating at tectonic plate boundaries with measurable magnitude and intensity.
• 🏞️ Earthquakes can lead to ground rupture, shaking, liquefaction, landslides, and tsunamis, posing significant risks to structures and communities.
• 🌄 Volcanic eruptions can result in lava flows, ashfall, ballistic projectiles, pyroclastic density currents (PDCs), lahars, and the release of volcanic gases.
• 💧 Lahars, or volcanic mudflows, are particularly dangerous and can be triggered by heavy rainfall or the sudden release of water from crater lakes.
• 🗻 Volcanic gases, such as sulfur dioxide and hydrogen sulfide, can have both short-term and long-term effects on the atmosphere and human health.
• 🪨 Landslides are the mass movement of rock, soil, and debris down slopes, triggered by factors like heavy rainfall, earthquakes, and human activities.
• ⚠️ During earthquakes, it's crucial to seek immediate cover under sturdy furniture and hold on until the shaking stops, rather than attempting to run.
• 🌊 Following strong earthquakes, moving to higher ground quickly can be a life-saving measure in the event of a potential tsunami.
• 🏠 During volcanic eruptions, it's advised to stay indoors or in designated evacuation areas to avoid the hazards associated with ashfall and other volcanic phenomena.

Q & A

What are geological processes?

Geological processes are events that occur at the Earth's surface, often due to natural forces like gravity, temperature changes, chemical reactions, and seismic shaking. These processes can lead to deformation, translocation, or chemical reactions when the forces exceed the strength of the Earth material.

What is the difference between magnitude and intensity in the context of earthquakes?

Magnitude is a measure of the energy released by an earthquake at the focus and is represented by Arabic numbers. It is calculated from recordings made by a seismograph. Intensity, on the other hand, is the strength of an earthquake as perceived and felt by people in a certain locality and is represented by Roman numerals.

What is liquefaction and how can it be caused by an earthquake?

Liquefaction is a phenomenon where sediments, especially near bodies of water, behave like a liquid due to the shaking during an earthquake. This can lead to sinking or tilting of structures above it.

What are the common hazards associated with volcanic eruptions?

Common hazards associated with volcanic eruptions include lava flows, ash or tephra fall, ballistic projectiles, pyroclastic density currents (PDCs), lahars, and volcanic gases.

Why are PDCs considered the most lethal of all volcanic hazards?

Pyroclastic density currents (PDCs) are considered the most lethal because they can cause incineration, asphyxiation, abrasion, dynamic pressure impact, and burial in hot volcanic material.

What is a lahar and how can it be triggered?

A lahar is a volcanic mud flow or debris flow, a slurry of volcanic sediment, debris, and water that cascades down a volcano slope. It can be triggered by rainfall on unconsolidated deposits, the sudden draining of a crater lake, or the movement of a PDC into a river or lake.

What are the effects of volcanic gases on the environment and living organisms?

Volcanic gases can cool the Earth's atmosphere, deplete its ozone concentration, and form aerosols. Some gases are toxic and can endanger livestock, while non-toxic gases like carbon dioxide can cause asphyxiation when released in large quantities.

What is a landslide and what can trigger it?

A landslide is a mass movement of rock, soil, and debris down a slope due to gravity. It can be triggered by natural factors like intense rainfall, weathering, or ground vibrations during earthquakes and volcanic activity, as well as by human activities such as mining, deforestation, and construction.

What should one do during an earthquake to ensure safety?

During an earthquake, one should follow the 'drop, cover, and hold on' protocol. This involves dropping to the ground, taking cover under a sturdy piece of furniture, and holding on until the shaking stops.

What is the appropriate response if one feels a strong earthquake near the shore?

If a strong earthquake is felt near the shore, one should move quickly to higher ground to avoid potential tsunamis, even without immediate information about the earthquake's source and location.