BIGGEST FAULT LINES on Earth

Number 5. The Main Euralian Fault The Main Euralian Fault runs more than 1,200 miles through the middle of the Ural Mountains in a north-south direction. It marks the line between Europe and Asia and has distinctively different types of rock on each side associated with those plates. It began to be formed about a billion years ago, during the breakup of the supercontinent known as Rodinia. The two main tectonic plates pulled apart and created a mid-ocean ridge which, hundreds of millions of years later, became the site of extensive geological changes, and was particularly active during the formation of Pangaea, which is when the Ural Mountains were formed. It's thought that the fault reaches very deep, at least 10 miles into the crust, which is the result of a complicated formation, and means that if at some point in the future a serious seismic event happens along the line, it could have significant consequences for large parts of Russia and Kazakhstan, and possibly even further. Number 4. The Atacama Trench The Atacama Trench, also known as the Peru-Chile Trench, is deep within the Pacific Ocean about 100 miles from the coast of Peru and Chile. Richard's Deep, its deepest point, is about 26,460 feet beneath sea level, and the entire fault is about 3,666 miles long and 40 miles wide. In 2018, three brand-new species were found in the depths of the trench, but it's for its destructive force that this fault line is important. It lies offshore from active volcanoes and is covered in the sediment of newly erupted ones. It's also an incredibly active area for earthquakes. In 2010, it caused the Chile earthquake, which measured 8.8 on the moment magnitude scale and caused a tsunami. In 1970, it caused the Ancash earthquake, which measured 7.9 and caused the deaths of around 68,000 people. And in 1960, it was the cause of the Valdivia earthquake, which, measuring in at 9.5, was the most powerful earthquake that's ever been recorded on our planet. Number 3. The Aleutian Subduction Zone The Aleutian Subduction Zone is about 2,500 miles long between the Alaska Range and the Kamkacha Peninsula. It's where the North American Plate and the Pacific Plate meet, with the Pacific Plate subducting beneath the North American one. The zone has created two main features, the Aleutian Island Arc and the Aleutian Trench. The Arc, named after the Aleutian Islands, extends 1,900 miles and is the location of more than 40 active volcanoes, including Mount Spur, which is in mainland Alaska, and Bull Deer Island in the island chain itself. The heightened volcanic activity is what created the island chain, and a number of the islands are still being formed by these processes. The trench continues along the entire oceanic part of the subduction zone, connects with other fault lines at each end, and reaches a maximum depth of 25,663 feet near to Bull Deer Island volcano. Recent research has suggested that this fault used to be far more active, with tsunamis being created once every 200 years or so. Most activity that's been discovered dates back to more than 2 million years ago, but it's still an active site today. In the past 75 years, there have been four earthquakes with a magnitude of more than 8, including a 9.2 on Good Friday in 1964, an 8.7 in 1964, and an 8.6 in 1957 that triggered a large, basin-wide tsunami. Smaller rumblings have been detected since, but it's been almost 60 years since one of noticeable impact, something researchers say is a sign that the next one could be imminent. 2. The Banda Detachment For decades, researchers have known about Weber Dep, a 4.5-mile-deep abyss near the Malacca Islands of Indonesia. That's the deepest point on Earth that's not within a trench. What's been a mystery about this location, though, is the question of how it was formed. But recent research has revealed the answer with the discovery of one of the world's biggest exposed faults, called the Banda Detachment. They were exploring the depths of the Banda Sea and found that the rock of the floor was scarred with hundreds of straight, parallel cuts. These marks show that a piece of crust larger than the size of Belgium had to have been torn apart to create the depression that remains. When faults form, they create a fault plane, which is a flat surface of a fault, and a fault line, where the fault plane intersects with the surface. The Banda Detachment fault plane was exposed over an area of 23,166 square miles when the crust cracked, which is by far the biggest to have ever been detected. Knowing about its location and learning how it affected the structure of the seabed is crucial to research into seismic area in the region. It's a part of the Ring of Fire where 75% of the world's volcanoes are, and where the most powerful earthquakes occur, and could be used to gain insight into how plates in the region will move. Discoveries of faults like this are also crucial because they have places that have the potential to cause devastating earthquakes and tsunamis, so must be monitored to provide as much warning as possible if they do become active. 1. The Sunda Megathrust The Sunda Megathrust is not only the biggest fault on Earth but also one of the most powerful. It runs from Myanmar in the north, along Sumatra, Java, and Bali before ending near Australia, a distance of more than 3,300 miles. It lies on the boundary where the Eurasian Plate is moving above the Indo-Australian Plate. So large is this fault that studies of its history have shown it to be segmented. This means that earthquakes often occur in different regions along it instead of along the entire structure at once. Earthquakes tend to occur in similar places to previous ones, although there's the possibility of much larger events, ones that are rare but extremely destructive. 2005's Nyasamulu earthquake, for example, had a moment magnitude of 8.6 and occurred in a similar place to an 8.5 earthquake in 1861. 2007's Sumatra earthquakes, which was one of the most powerful, measured at 8.4, occurred at the same place as the 1833 Sumatra earthquake. All four of these quakes were some of the most powerful ever recorded, but the true power of the Sunda Megathrust is much greater. In 2004, after lying dormant for more than a thousand years, a more than 1,000-mile section of the fault suddenly slipped and caused an uplift on the seafloor between Assay and Myanmar. Known as the Sumatra-Andaman earthquake, this monstrous movement was measured at between 9.1 and 9.3 moment magnitudes and caused a series of tsunami waves that were 100 feet tall. The devastation was widespread, and just under 230,000 people were killed in what was one of the deadliest natural disasters in recorded history. It was the third-largest earthquake ever to have been detected and released so much energy that it caused the whole planet to vibrate by four-tenths of an inch and triggered further earthquakes as far away as Alaska. Honorable Mentions The San Andreas Fault The San Andreas Fault line is a 750-mile-long transform fault line through California that boundary between the Pacific Plate and the North American Plate. It splits into three sections, the northern, central, and southern, and for a long time, only the northern part was known about. Following the 1906 San Francisco earthquake, which had a moment magnitude of 7.9, destroyed 80 percent of the city and killed 3,000 people, it was finally realized how far it went into Southern California. This fault is one of the most studied seismic regions on the planet for two reasons. The first is that one part of it is remarkably predictable. The region near Parkfield in California produces a magnitude 6 earthquake approximately once every 22 years, so the region has been filled with sensors to pick up as much data as possible when it next happens. The other reason for the interest in the San Andreas Fault is that researchers believe it's overdue for a quake in excess of magnitude 7, something they call the Specifically, this is expected to happen on the southern section because this region hasn't seen a large event for more than 300 years. This is the region around Los Angeles, so has the potential to be an incredibly deadly and costly event if it does ever happen. The Queen Charlotte Fault The Queen Charlotte Fault is Canada's equivalent to the San Andreas Fault and is also on a boundary between the North American and Pacific Plates. It begins at the Queen Charlotte Triple Junction, where it meets with two other plates and goes northwards along the Alaskan coast. It has been the source of a number of large earthquakes such as a magnitude 7.8 quake in 2012, a 7.4 quake in 1970, and Canada's largest measured earthquake in 1949 which reached a moment magnitude of 8.1. Luckily, these all happened in low-population areas, so there were no fatalities. But the frequency of events here means that it's a popular place for researchers to visit who are trying to develop early warning systems for regions elsewhere in the world. I hope you all enjoyed today's video narrated by Zach this time. Be sure to subscribe for more and check out some of our recent uploads.