Tsunamis: the Geology Behind the Deadly Wave Tsunamis are damaging natural disasters that are universally feared. Nature can be one of the entities that terrifies humans the most. These disastrous tsunamis can be caused by many different situations. Geology is closely connected to the production of tsunamis and their occurrences. It is also a useful tool in identifying the causes of tsunamis in ancient times. All tsunamis are tied to rocks and minerals, which cause earthquakes. When the ocean floor moves, water is thrust upward, thus causing a tsunami. These giant waves of destruction are caused by volcanoes, earthquakes, and underwater landslides. Earthquakes are more common in the causing of tsunamis than any other cause. Some notable tsunamis throughout history are the Mt. Etna …show more content…
These deposits are sedimentary and are left behind when the tsunami pulls back out to sea. These deposits can often be found in lagoons just off the coastline. The sediments are fine-grained. Sometimes boulders can be used to identify past tsunamis but this is not a reliable approach due to cyclones and other natural disasters having the same ability of boulder movement. These deposits help scientists to uncover the truths about the pasts and even determine the magnitude of a historical earthquake. There was an earthquake in 869 in Sendai and Honshu called the Sanriku earthquake. The scientists were able to uncover facts about the earthquake due to the sediments left behind from the resulting tsunami. The term used to describe these scientists and their profession is Palesoseismology. They look at sediments and rocks and observe them. Using the observations, they uncover the truth of ancient earthquakes in the past. This is helpful to inform people of seismic hazard and to prevent widespread damage. If there has been an earthquake previously then there is likely to be one again. This may take place now or 100,000 years from
The most noticeable difference between a tsunami and a hurricane is the cause of each. A tsunami is the aftermath of an underwater earthquake or volcanic eruption. The force of the earthquake or eruption, along with the moving of the tectonic plates, sends large amounts of water in all directions. The waves can be thousands of feet high when they reach the shoreline. These giant waves can arrive at a moment's notice with no warning. The tsunami is a large natural phenomenon originating from the ocean, but it is not the only phenomenon to start in the ocean.
That is the image of a tsunami and they strike somewhere in the world almost every year. Some archeologists say that a mediterranean tsunami hit the north shore of Crete about 3500 years ago which sent Minoan civilization to surrender to Mycenaen Greeks. In the fifth century B.C. the Greek historian, Thuydides, was the first to document the connection between earthquakes and tsunamis. The majority of tsunamis are in the Indian and Pacific oceans where the Tectonic plated collide and the one carrying dense oceanic crust dives under the more floatable one forming a deep ocean trench. Normally it happens smoothly, but sometimes they become stuck and friction strain builds up, then it releases energy which raise and lower the water above it which becomes a tsunami. Created from the seafloor up they grow in dangerous heights in shallow waters only because in the deep oceans it barely
Some believe that the 2004 Indian Ocean tsunami was caused by an Indian-Israeli-American nuclear test. The possibility that it was some kind of human intervention that destabilized the tectonic plates, an invention that is caused only in nuclear experiments and explosions. The most popular theory is that the Indian and U.S. military are the “main cause of the disaster by testing tectonic weapons, which use electromagnetic waves, thus triggering
Tsunamis are caused by earthquakes underneath the ocean, which can results in gigantic waves that cause devastation and change the Earth’s surface by causing radiation and causing underwater landslides. In the article “Is Santa Catalina Island Sinking or Rising?” it describes how an effect of tsunamis. It states, “A tsunami could have struck the coast from Catalina when the underwater landslide occured” (Los Angeles Times 2). Therefore, tsunamis can strike coasts and can create landslides underwater, changing the ocean floor by creating caves and canyons. Also, tsunamis can wear away beaches. When giant waves crash into coasts of masses of land, they can wear away the coast. Finally, tsunamis can cause radiation. In the article “Dangerous Tsunami Threat off U.S. West Coast,” it explains, “It [the tsunami] also damaged a nuclear power plant, causing a meltdown and spreading dangerous radiation in the area” (Los Angeles Times). Consequently, tsunamis can destroy and interfere with human made buildings which may contain toxic gases which may be released into the air and cause damage the environment. Incidentally, damaging the environment can lead to killing plant and animal life, and the Earth in that area could potentially become barren and
Throughout this unit, the Science in Practice class has been learning about natural disasters and the impact it has on humans and environment. The natural disaster that will be discussed in this report is the Boxing Day Tsunami, which occurred on the 26th of December, 2004. The tsunami took place in the Indian Ocean. Due to, two tectonics plates, the Indo-Australian plate and the Eurasian plate colliding, causing an underwater earthquake. Due to this awful disaster, people were killed, injured, diagnosed with diseases, homes and businesses were destroyed, the environment damaged.
Tsunamis occur when an earthquake happens in the ocean and the energy goes to the water creating huge waves. Tsunamis are very dangerous they can be so strong that they wash away the city, harm thousands, and cause hundreds of thousands to billions of dollars in damage. “A giant tsunami along the West Coast would wash away coastal towns, destroy U.S. Highway 101 and cause $70 billion in damage. More than 100 bridges would be lost, power lines toppled and coastal towns isolated. Residents would have as few as 15 minutes’ notice to flee to higher ground, and as many as 10,000 would die” (Dangerous tsunami threat off U.S. West Coast). This shows what kind of damage this geo-process can
Since these earthquakes are caused by tectonic plate movement therefore displacing the ocean floor they are almost always accompanied by massive ocean waves, sometimes reaching heights of over 100 ft and reaching speeds of 500 mph, known as seismic sea waves or more commonly known as Tsunamis4. Alongside the catastrophic events that megathrust earthquakes ensue on an affected region these colossal Tsunami waves further destruct costal lines in their path, sometimes reaching many miles inland.
The Tsunami that took place after the initial quake was caused by a portion of seabed rupturing upwards, and displacing a large portion of the water being displaced. This water traveled at 450 miles, at 8 feet tall, to the Chilean and Peruvian coast. Early viewers of the tsunami later reported waves being up to 10 feet tall. This rupture was believed to be caused by 2 unusually dense pieces of seabed that had been previously undetected by scientists, and consequently caused a large displacement of water. There were also small ruptures of seismic
As survivors from the quake rushed around in fear and confusion, they were greeted by yet another disaster. Shortly after the earthquake, a tsunami occurred. The tsunami’s waves struck the coastline beginning at twenty feet. But as more waves hit the coast, the height of the tsunami grew to just under forty feet, taking out everything that hadn’t already been destroyed by the earthquake, reducing the entire city to rubble. The tsunami stretched across sixty-two miles of coastline near Messina, and another twenty-four miles of coastline near Calabria. The damage from the tsunami was greater near the Calabria coast, where waves were higher and the water quickly swallowed houses and bridges, and flooded rivers. The tsunami that occurred in Messina still holds the title for one of the biggest tsunamis in today’s history. Recently, however, geologists have revisited origin of the tsunami, which is now widely debated. Some
Tsunamis occur when there is sudden movement in an extensive body of water such as earthquakes, landslides on the sea floor, major volcanic eruptions or meteorite impacts. The most common source of a tsunami is earthquakes, which are another type of geomorphic hazard that is caused by the friction and stress that tectonic plates put on each other. Tsunamis primarily occur in coastal or island regions where there is a tectonic border or what is known as the ring of fire. As shown in the diagram below the ring of fire is located along the coastal and island regions of the world.As a result of the Pacific Plate diving beneath the Eurasian plate, on March 11, 2011, there were 2 geomorphic hazards, a magnitude-9 earthquake struck north Japan, which caused a deadly tsunami that reached heights of 39 meters. The destructive dilemma was dubbed ‘The Great Sendai Disaster’. The earthquake was caused by multiple centuries of stress on the tectonic plates surrounding the island. The earthquake caused a tsunami that reached the height of 39 meters (128 feet). Japanese scientists had previously discovered that there was another tsunami just like the one in 2011 that took place in 869 AD. But their warning was unhindered. The tsunami, which occurred in 869 AD, was caused by the same tectonic fault as the 2011 tsunami. The epicenter of the earthquake was off the northeast cost of Japan leading to a devastating tsunami that killed many and left many wishing they were. The massive earthquake caused an upward wave that headed towards the city of Sendai. Researches have recently uncovered a thin layer of clay that lubricated the fault zone causing the deadly tectonic slip, thus creating a tsunami that could wipe out an entire city as it did in 2011.The aftermath of the 2011 tsunami and earthquake was not pretty; it caused many deaths, injuries, traumas, financial difficulties, destruction of property, health bills and the destruction of the landscape as a whole. The natural disaster caused nearly 16,000 casualties and there are an estimated 2,500 people still reported missing. Although drowning caused most deaths others include, crushed by debris, suicide and diseases caused by nuclear radiation (cancer) spilled from nuclear
Tectonic activity varies due to geographical location and position of tectonic plate boundaries. The Earth's crust is made up of continental and oceanic plates, which move across the surface of the planet, meeting at plate boundaries. Plate tectonics cause volcanic activity, tsunamis and
The crust and top of the mantle make up the land but they aren't just one big piece they are made up of many pieces called tectonic plates, which look like puzzle pieces. The plate boundaries are made up of lots of fault lines, and most of the earthquakes around the world happen on these fault lines, Because the edges of the plates are rough, they get stuck but the rest of the plate keeps moving. Finally, when the plate has moved far enough, the edges unstick on one of the faults and there is an earthquake. Some earthquakes happen out at the bottom of the sea which most of the time causes a tsunami because the earthquake opens the sea floor which then makes the water fill in the gap but when the gap closes again it pushes the water out which causes a tsunami.
An average of two tsunamis occur every year through the world that damages the land nearest to it. Also on average every fifteen years a destructive ocean-wide tsunami occurs.
too much weight is put upon an underwater slope. The underwater avalanches can then trigger
A tsunami is a series of huge waves occurring when there is a major disturbance on the ocean floor. Tsunamis often occur due to earthquakes, volcanoes, or landslides (Park 16). Underwater earthquakes may produce waves that travel in all different directions. Some tsunamis lose power and die out under water, others may produce large waves as they approach land. Tsunamis may look like an onrushing tidal wave as they approach land, but do not occur because of tides (Park 6). Their walls of water can move across the open ocean at speeds of up to 560 miles per hour. When the waves hit the coast, they can reach up to 100 feet (Park 5). The tsunami in Japan is believed to have occurred after two of Earth’s tectonic plates collided in the