California Geological Survey Tsunami Demonstration

California Department of Conservation

30 Sept 202203:35

Summary

TLDRCindy Pridmore, a senior engineering geologist, explains tsunamis using a model. Tsunamis are caused by ocean floor displacement, often from faults moving upwards. They can travel vast distances, like the 2011 Japan tsunami that reached California in nine hours. Tsunamis are rare in California but can occur. Pridmore demonstrates using a tsunami bottle, showing how a tsunami forms and the importance of seeking higher ground. She emphasizes the need to stay away from the water until it's safe, and advises viewers to check the California Geological Survey website for more information.

Takeaways

🌊 Tsunamis are caused by the uplift of the ocean floor, which can be triggered by faults or other geological events.
🗺️ Tsunamis can travel vast distances across oceans, as evidenced by the 2011 Japan tsunami reaching California.
🏔 Tsunamis are not frequent in California but are a known possibility due to geological activity.
🏡 The tsunami bottle model demonstrates how tsunamis form and the importance of seeking higher ground during an event.
🚀 Tsunamis are generated when the ocean floor is pushed up, causing the water to rise and then spread out in all directions.
🏞️ In the model, a safe place during a tsunami is represented by a high area, indicating the need to evacuate to higher ground.
🌊 The model shows that when a tsunami is generated, it flows towards the coastline, emphasizing the need for quick evacuation.
🕒 Tsunamis can last for many hours, so it's crucial to stay away from the water until it's declared safe.
🚦 Tsunami warning signs in coastal areas serve as reminders of potential tsunami risks and the need for awareness.
⏰ There will be official warnings and instructions to evacuate if a tsunami is generated, ensuring time to reach safety.
📚 The California Geological Survey website provides more information and resources about tsunamis for those interested.

Q & A

What is a tsunami?
-A tsunami is a large ocean wave caused by the movement of the ocean floor, often due to an earthquake or other geological events.
What causes tsunamis?
-Tsunamis are caused by the pushing up of the ocean floor, such as when a fault moves upward, causing the water to rise as well.
How do tsunamis travel?
-Once generated in the ocean, tsunamis travel outwards in all directions due to the force of gravity pulling them back down.
Can tsunamis reach California?
-Yes, tsunamis can reach California from distant places like Japan, as evidenced by the 2011 event, or from closer regions like Alaska.
How long does it take for a tsunami to travel across the ocean to California?
-The 2011 Japan tsunami took approximately nine hours to reach California.
What is the purpose of the tsunami bottle demonstrated in the script?
-The tsunami bottle is a model used to visually explain how tsunamis are generated and how they affect the coastline.
How does the tsunami bottle simulate a tsunami?
-The tsunami bottle simulates a tsunami by lifting the 'ocean floor' with a string, causing the water to rise and flow towards the coastline.
What is the recommended action to take during a tsunami?
-The recommended action is to go to higher ground or move inland away from the water.
How long can tsunamis last?
-Tsunamis can last for many hours, so it is important to stay away from the water until it is declared safe.
What are the blue and white signs mentioned in the script, and what do they indicate?
-The blue and white signs indicate that you are in a tsunami zone, reminding people of the potential for a tsunami in that area.
What will officials do if a tsunami is generated?
-Officials will provide a warning and instruct people to leave the beach and move to higher ground for safety.

Outlines

00:00

🌊 Tsunamis: Origin and Impact

Cindy Pridmore, a senior engineering geologist at the California Geological Survey, introduces tsunamis as natural disasters caused by the upward displacement of the ocean floor. She explains that when faults move, they push the water up, generating tsunamis that travel across the ocean. Tsunamis can travel long distances, as exemplified by the 2011 Japan tsunami that reached California in nine hours. She also mentions the potential for tsunamis from Alaska and the Cascadia subduction zone. To illustrate the concept, Pridmore uses a homemade tsunami bottle, simulating the movement of the ocean floor and the subsequent flow of water towards the coast, emphasizing the importance of seeking higher ground during a tsunami.

Mindmap

Keywords

💡tsunami

A tsunami is a series of ocean waves caused by a large-scale disturbance in the ocean, typically an undersea earthquake or volcanic eruption. In the video, tsunamis are discussed as natural disasters that can impact California, with examples given of tsunamis originating from distant places like Japan and closer locations such as Alaska. The video emphasizes the importance of understanding how tsunamis are generated and the potential threat they pose to coastal areas.

💡ocean floor

The ocean floor refers to the bottom of the Earth's ocean basins. In the context of the video, tsunamis are generated when the ocean floor is 'pushed up' due to geological activity like faults moving upwards. This upward movement displaces water, leading to the formation of a tsunami. The video uses a diagram to illustrate how a fault in the ocean floor can trigger a tsunami.

💡fault

A fault in geology is a planar fracture or zone of fractures where the rock bodies on either side have moved relative to each other. The video script mentions a fault as the cause of a tsunami, where movement along the fault line can uplift the ocean floor, leading to the displacement of water and the creation of a tsunami.

💡Cascadia subduction zone

The Cascadia subduction zone is a region where the oceanic plate is being forced under the continental plate, which can cause significant seismic activity. The video mentions this zone as a potential source of tsunamis that could affect California, highlighting the importance of being aware of geological features that can contribute to tsunami generation.

💡tsunami bottle

A tsunami bottle is a demonstration tool used to visually explain how tsunamis are formed. In the video, Cindy Pridmore uses a homemade tsunami bottle to illustrate the concept of a tsunami. By pulling a string, she simulates the movement of the ocean floor and the subsequent wave that travels towards the coastline, providing a practical example of tsunami generation.

💡continental slope

The continental slope is the gradual slope of the sea floor from the continental shelf to the deep ocean. In the video, the continental slope is represented by a cutting board weighted down to simulate the underwater topography. This is important for understanding how tsunamis travel and the potential impact on coastal areas.

💡high ground

High ground refers to elevated areas of land that are above the normal level of a body of water. The video emphasizes the importance of seeking high ground during a tsunami as a safety measure. It is depicted in the tsunami bottle demonstration where a piece of land represents a safe area to avoid the effects of the tsunami.

💡tsunami warning signs

Tsunami warning signs are indicators placed in areas at risk of tsunamis to alert the public of potential danger. The video mentions these signs as a reminder that one is in a tsunami-prone area. They serve as a visual cue to be aware of the environment and to take necessary precautions if a tsunami occurs.

💡tsunami zone

A tsunami zone is a geographic area that is at risk of experiencing a tsunami due to its proximity to potential tsunami-generating sources. The video script refers to these zones, particularly in California, and the importance of being aware of one's location relative to such zones to ensure safety during a tsunami event.

💡official warning

An official warning in the context of the video refers to the alerts issued by authorities to inform the public of an impending tsunami. The video assures viewers that there will be time for officials to provide warnings, allowing people to evacuate coastal areas and move to higher ground for safety.

💡California Geological Survey

The California Geological Survey is the state agency responsible for reducing the risk of geologic hazards, including tsunamis. The video script encourages viewers to visit their website for more information on tsunamis, indicating their role in educating the public and providing resources to understand and prepare for such natural disasters.

Highlights

Tsunamis occur due to the pushing up of the ocean floor.

When the ocean floor moves up, the water gets pushed up too.

Tsunamis are generated in the ocean and travel in all directions.

Tsunamis can travel long distances, such as from Japan to California.

The 2011 Japan tsunami took about nine hours to reach California.

Tsunamis can also originate from Alaska and the Cascadia subduction zone.

Tsunamis are not frequent in California but are known to occur.

A tsunami bottle is used to demonstrate the generation and movement of tsunamis.

The bottle model shows the continental slope and on-land areas.

During a tsunami, water flows towards the coastline.

High ground is a safe place to be during a tsunami.

Tsunamis can last for many hours, so it's important to stay away from the water until it's safe.

Tsunami warning signs are present in coastal areas, indicating potential tsunami zones.

Officials will provide warnings and instructions during a tsunami event.

The California Geological Survey website offers more information and videos about tsunamis.