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15 BIGGEST Earthquake Zones
Transcript
00:00Earthquake faults are fractures in the Earth's crust where the tectonic plates push against each other, causing earthquakes.
00:06Today, we're counting down 15 of the biggest earthquake zones in the world.
00:10Let's start with number 15, the Denali Fault.
00:13Located high up in the north between both Alaska and the Yukon,
00:17the Denali Fault is more than 2,000 kilometers long and is a strike-slip fault.
00:23This means that it's a fracture in the Earth's crust where rock masses slide past each other horizontally.
00:29And in this case, the Denali Fault is strong enough to cause some seriously destructive earthquakes.
00:34So, if you're ever on a trip to this area of the Arctic,
00:37I'd suggest looking for earthquake warnings before beginning your trip.
00:42Number 14, the North Anatolian Fault.
00:46Stretching right across northern Turkey, both it and its neighboring faults cover most of this dynamic country.
00:52Considered to be very similar to the infamous San Andreas Fault,
00:56thanks to both its length and its slip rate,
00:58the North Anatolian Fault is 1,500 kilometers long
01:01and is known for sparking off many strong earthquakes in recent memory.
01:05Over the past century, it appears that its earthquakes have been moving in a broadly westerly direction,
01:10and this is a problem, as earthquakes seem to be moving closer and closer to Istanbul.
01:16Number 13, Campi Flegrei.
01:19While Italy is known for being a beautiful vacation spot,
01:22it regularly has to deal with the Campi Flegrei,
01:25a vast volcanic area that includes places such as Pompeii and Naples.
01:29It is one of the most seismically active places in Europe,
01:33and to make matters worse, the area has seen an increased ground displacement.
01:37After all, it's risen by 1.15 meters since 2005,
01:41and ever since August of 2023, the area has been surpassing 1,000 earthquakes per month.
01:48As a result, millions have been allocated to monitor the areas increasingly concerning volcanic and seismic activity.
01:55Number 12, the Himalayan Frontal Thrust.
01:59Located on the boundary between the Himalayan foothills and Indogenes Plain,
02:03the Himalayan Frontal Thrust is one of the most visible fault lines on this list.
02:08After all, it's so well expressed on the surface that it can be seen via satellite imagery.
02:13Well, given that it covers almost the entire Indian Plate,
02:16it should also be of little surprise that it's geologically active.
02:19After all, many earthquakes associated with it have created visible ground ruptures,
02:24and this is something that's not expected to be any different with future earthquakes.
02:29Number 11, the New Madrid Seismic Zone.
02:32So, contrary to what its name suggests, the New Madrid Seismic Zone has nothing to do with Spain,
02:38South America, or many other Spanish-speaking countries.
02:42Rather, it's a fault line located across the American Heartland and Southeastern Missouri,
02:46Northeast Arkansas, Western Tennessee, Western Kentucky, and Southern Illinois.
02:52While it creates hundreds of earthquakes every year, most of them are pretty tiny
02:56and can only be detected with the help of very sensitive measuring equipment.
03:00And while it's created its fair share of major earthquakes in the past,
03:03the reality is that the Western United States is far more earthquake-prone than the East.
03:09Number 10, Venus Quakes.
03:12So, it turns out that Earth isn't the only place where quakes occur.
03:17That's because on our neighboring planet of Venus, these natural disasters are pretty common.
03:22The only difference is that while we deal with earthquakes that come from the ground,
03:26Venus, rather terrifyingly, deals with earthquakes that come from the sky.
03:30This is possible to Venus's extremely thick atmosphere.
03:34More specifically, this atmosphere generates enormous amounts of friction.
03:38Now, this friction creates heat, which in turn causes the rocks on Venus's surface to expand and contract.
03:44Now, this process creates cracks and fissures in the rocks,
03:47and eventually, these friction fissures can cause earthquakes.
03:50In terms of strength, Venus quakes can be pretty powerful.
03:53According to scientists, this strength is comparable to the most forceful earthquakes ever recorded on Earth.
03:59However, due to Venus's thick atmosphere,
04:01the shaking caused by these quakes is much less intense than what we experience.
04:05However, while we know that Venus quakes exist,
04:08what we aren't able to do is detect when they happen in real time.
04:12But this may change pretty soon.
04:13In April of 2022, scientists detected an earthquake using instruments flying in a balloon above California.
04:20The hope is that similar balloons could one day be deployed in Venus's middle atmosphere,
04:25as the pressure and heat on the surface make it virtually impossible to land standard space equipment.
04:30It also appears that Venus quakes may cause landslides to happen.
04:33You see, all the way back in November of 1990,
04:35images of landslides on Venus were taken by the Magellan spacecraft.
04:39Another image was taken on July 23rd of 1991,
04:42and when looked at close up, these images show a region within what's known as the Aphrodite Terra.
04:47This region is characterized by steeply sloping valleys that's cut by many fractures.
04:52So, if quakes do happen on Venus, Aphrodite Terra may be one of the epicenters of activity.
04:58But the reality is that until we have better tech and better data about the planet,
05:02it's going to be hard for us to pinpoint exactly where Venus's most prolific Venus quake zones are located.
05:11The Japan Trench.
05:13It's part of the larger and more famous Pacific Ring of Fire,
05:16although it's become quite famous in its own right.
05:19It's located at a point where the oceanic Pacific plate subducts beneath the continental Okhotsk Plate.
05:25It's an impressive 800 kilometers in length, and at its deepest point,
05:28it reaches a whopping 8,000 meters in depth.
05:31Beyond making it one of the main causes of tsunamis and earthquakes in northern Japan,
05:35this trench has also gained fame for its tendency to create what are known as slow earthquakes.
05:41Now, by definition, slow earthquakes are discontinuous, earthquake-like events
05:46that release energy over a period of hours to months,
05:49rather than seconds to minutes that are typical for an earthquake.
05:52A study on this phenomenon was conducted in 2023, and the results were surprising.
05:57The researchers found that the Japan Trench has a mix of both slow and fast earthquakes,
06:02which interact in complex ways.
06:04Slow earthquakes seem to play a role in starting and stopping large megathrust earthquakes.
06:09However, the researchers still don't fully understand why this happens.
06:13As of now, they did note that there is some connection
06:16between where slow earthquakes occur and the structure of the Earth's crust.
06:20More specifically, they believe that pressurized fluids might be a key factor in causing slow earthquakes,
06:25yet it will take significantly more study before the researchers come to a solid conclusion.
06:30It's also worth noting that in January of 2020, researchers made an interesting discovery.
06:35You see, in March of 2011, a devastating earthquake happened,
06:38and in due time, scientists began looking into answers as to why.
06:42When they looked at the structure of the fault line,
06:44researchers were stunned to find an unprecedented 50 meters of shallow displacement along the fault,
06:50which ruptured all the way to the surface of the seafloor.
06:54This extreme slip at shallow depths is believed to have exacerbated this terrible seismic event.
06:59The researchers also found evidence of there being a long history of large earthquakes in this fault zone,
07:05as they found multiple faults with evidence of more than 10 meters of slip during major events.
07:10So, for all the good of those living in the region,
07:13we expect there to be further studies on this fault
07:15in order to make it easier to predict and plan around earthquakes.
07:21Number 8. The Banda Detachment
07:24Of all the faults on this list, the one that has the most recent discovery is the Banda Detachment.
07:29You see, in 2016, researchers confirmed the existence of the largest exposed fault on Earth.
07:35Discovered beneath the Banda Sea in eastern Indonesia,
07:38this massive fault plane runs right through the notorious Ring of Fire.
07:42While this is significant in its own right,
07:45it's also important because it may explain why the 7.2-kilometer-deep Weber Deep Abyss
07:50exists in the middle of the Pacific Ocean.
07:52You see, when a fault forms on Earth's crust, it forms in two main features,
07:56a fault plane, which is the flat surface of a fault,
07:59and the fault line, which is the intersection of the fault plane with the ground surface.
08:04The team's simulation showed that the Banda Detachment fault plane
08:07was exposed over an area of 60,000 square kilometers,
08:10when at some point, the seafloor cracked.
08:13Simulations of the seafloor suggest that when this crack opened,
08:16a massive piece of crust, bigger than Belgium,
08:19was ripped apart to form a deep depression in the ocean floor.
08:22This depression is the Weber Deep, which still exists today.
08:27Moving on to number seven, the Mid-Atlantic Ridge.
08:31Of all the earthquake zones out there,
08:33one of the most impressive, size-wise, is the Mid-Atlantic Ridge.
08:37Located along the floor of the Atlantic Ocean,
08:39and stretching right from the North Atlantic to the South,
08:42it's notable for being the longest mountain range in the world,
08:45coming in at an incredible length of 16,000 kilometers.
08:49About 90% of it is located underwater.
08:52However, it is technically part of an even larger,
08:55nearly continuous 40,000-kilometer system of mid-ocean ridges
08:59that stretches all across the Earth's oceans.
09:02It was formed thanks to the movement of the Earth's plates.
09:04More specifically, as these plates push apart,
09:06mountains and valleys form along the seafloor,
09:09as magma rises up to fill the gaps.
09:12As the Earth's crust spreads,
09:13a new ocean floor is created,
09:15renewing the surface of the planet as it does so.
09:18In fact, if you look at a map of the world's volcanoes,
09:20you'll find that most of them have formed along the boundaries
09:22of the Earth's mid-ocean ridge system.
09:25This makes it the largest single volcanic feature on the Earth.
09:28The ridge's plates pushing is also something that's continuous
09:31and still happening to this day.
09:33It's because of this that the ridge has an average spreading rate
09:36of about 2.5 centimeters per year.
09:38So as you might imagine,
09:39this help makes the ridge seismically significant.
09:42You see, the Mid-Atlantic Ridge includes a deep rift valley
09:45that runs along the axis of the ridge for nearly its entire length.
09:49This rift marks the actual boundary between the adjacent tectonic plates.
09:53And in particular, its central valley is very seismologically active
09:57and the epicenter of many earthquakes that can then form tsunamis.
10:01This ridge is also responsible for a large percentage of the islands
10:04that are found in the Atlantic Ocean.
10:06Iceland is one of the most notable examples.
10:09Situated directly above the ridge's most westernmost section,
10:12the movement of the tectonic plates was directly responsible
10:15for the formation of Iceland.
10:17More specifically, around 25 million years ago,
10:19the North American and Eurasian tectonic plates began to move apart.
10:24This movement created a rift valley along the Mid-Atlantic Ridge,
10:27which eventually led to the formation of a series of volcanoes.
10:31Over time, the volcanic activity from those volcanoes became more intense,
10:34leading to the formation of Iceland's incredible landscape.
10:38Today, though, Iceland is one of the only places on Earth
10:41where the Mid-Atlantic Ridge is visible above sea level,
10:43making it a truly unique place.
10:46However, it's worth noting that the other islands,
10:48such as the Ascension Island and St. Helena and the Azores,
10:51also owe part of their creation story to the Mid-Atlantic Ridge.
10:55So, while its activities may often be rather dangerous,
10:57it's certainly clear that the Mid-Atlantic Ridge
11:00is responsible for creating some of the coolest places on Earth.
11:07Also known as the Ring of Fire,
11:09the Pacific Rim is far and away the world's largest
11:13and most dangerous earthquake zone.
11:15Coming in at about 40,000 kilometers in length
11:18and about 500 kilometers in width,
11:20it surrounds most of the Pacific Ocean in a horseshoe shape.
11:24In terms of its seismic stats,
11:26it's nothing short of impressive.
11:28After all, it contains between 750 and 915 active and dormant volcanoes,
11:34which is around two-thirds of the world total.
11:37It's also responsible for about 90% of the world's earthquakes,
11:40including most of the world's largest ones.
11:43Now, it is worth noting that the Pacific Rim
11:45isn't one massive fault line, plate, or rift.
11:49Rather, it's a series of these that are all interconnected.
11:52More specifically, this area is where a lot of the world's
11:54tectonic plates interconnect,
11:56and this in turn creates various zones
11:58where it's common for seismic activity to happen.
12:01Now, interestingly, this is the type of plate tectonic setup
12:03that also helps form some of the Earth's deepest ocean trenches.
12:07The trenches form because as one plate subducts under another,
12:10it's bent downwards,
12:12and it is possible for deep undersea earthquakes to happen
12:14as the two plates scrape against each other
12:16and as the subducting plate bends.
12:18This type of activity can also cause tsunamis to form above the surface,
12:22devastating coastal areas.
12:24But of all the spots in the Pacific Rim,
12:26the Mariana Trench is easily the most famous.
12:29It's located in the West Pacific.
12:31It drops to a depth of about 11 kilometers.
12:34For reference, this is so deep
12:35that if you were to drop Mount Everest inside of it,
12:37its peak would still be more than a kilometer underwater.
12:41When you further consider the trench's array of fascinating deep-sea species,
12:45it is easy to make an argument
12:47that it is one of the coolest places on the planet.
12:49And it's also worth noting that the Pacific Rim
12:51is the only spot on this list to be the subject of a famous sci-fi movie franchise.
12:56Made in two installments,
12:57Pacific Rim in 2013 and Pacific Rim Uprising in 2018,
13:01it's set in a future where Earth is at war with the kaiju.
13:04These kaiju are colossal sea monsters
13:06which have emerged from an interdimensional portal in the bottom of the Pacific,
13:10and it's only with the help of massive humanoid robots
13:12that the humans are able to fight them.
13:14And I won't be providing any spoilers here,
13:16but the two films got Rotten Tomatoes scores of 72 and 42% respectively,
13:21suggesting that while the first film was pretty good,
13:23the second one was pretty rotten.
13:29While New Zealand may look like an idyllic place
13:32filled with beautiful views, sheep, and homages to the Lord of the Rings,
13:36the reality is that it's in an extremely dangerous seismic region
13:40known as the Alpine Fault.
13:41Having no relation to the mountains of Italy, Switzerland, Austria, or France,
13:45the Alpine Fault runs across almost the entire length of New Zealand's southern island.
13:50In total, it runs for an impressive 600 kilometers
13:52and visibly protrudes where the boundaries of the Pacific and Australian plates collide.
13:57Now, in terms of growth, the Alpine Fault is one of the fastest movers on the planet.
14:01After all, the horizontal movement of this fault is about 30 meters per thousand years,
14:05which is considered very fast by global standards.
14:09Each time it's ruptured, it's also moved vertically,
14:11lifting the Southern Alps in the process.
14:13In fact, over the past 12 million years,
14:15the Southern Alps have been uplifted by an amazing 20 kilometers.
14:19For reference, that's more than the height of two Mount Everest stacked on top of each other.
14:23And it's only because of the fast pace of erosion
14:25that the highest point has been kept below 4,000 meters.
14:28This eroded material has been spread across the lowland plains
14:31or onto the seafloor via glaciers and rivers,
14:34helping contribute to New Zealand's incredible landscape.
14:37It's also worth noting that, generally speaking,
14:39the Alpine Fault has little historical documentation.
14:42You see, while the Maori arrived in New Zealand around the year 1300,
14:46they never reached a high population density in the colder South Island.
14:50As a result, while earthquakes are an important part of the Maori oral tradition,
14:54no stories have been passed down about South Island earthquakes.
14:57This lack of documentation is made worse
14:59by the fact that it had very few high-action earthquakes.
15:02According to scientists, only four have been over at a magnitude eight
15:06over the past thousand years.
15:07In fact, for decades, it was so quiet
15:09that it was speculated that the Alpine Fault creeps without causing any large earthquakes.
15:14However, better equipment has revealed to us the truth
15:17that, in actuality, it may rupture in a big way rather soon
15:20and likely in the next 50 years.
15:23And when I say big, I mean it.
15:24After all, it's believed that this rupture is going to produce
15:26one of the biggest earthquakes since the European settlement of New Zealand.
15:30You know, it's also worth mentioning that the Alpine Fault
15:32was the subject of the Deep Fault Drilling Project,
15:35or the DFDP for short,
15:37and while work on it first began in 2011, it was completed in 2014.
15:41Its goal was to retrieve rock and fluid samples
15:44and make geophysical measurements inside the fault zone.
15:48After spending two and a half million bucks
15:49and drilling for 1.3 kilometers down in two months,
15:52they eventually found what was described as
15:55extreme hydrothermal activity,
15:57which could be commercially very significant.
16:04The East African Rift isn't a single fault,
16:06but rather a series of faults and fault zones
16:09that are absolutely massive.
16:11Considered to be one of the most extensive rifts on the Earth's surface,
16:14its location extends from Jordan in southwestern Asia,
16:18southward through eastern Africa to Mozambique.
16:21In total, it comes in at over 6,400 kilometers in length
16:24and between 48 to 64 kilometers in width,
16:27making it absolutely massive.
16:29The rift is also impressive due to its visibility.
16:32After all, it is by definition a splitting of the Earth's crust,
16:35and this can be seen in the region's geography
16:38and high percentage of volcanoes.
16:40The splitting is also visible within the area's lakes,
16:43which are so deep and fjord-like
16:45that some have their bottoms well below sea level.
16:48Now, this system consists of two branches.
16:50The main branch, which is known as the Eastern Rift Valley,
16:53extends through Ethiopia and Kenya,
16:56while the second branch, which is known as the Western Rift,
16:58runs in an arc from Uganda to Malawi.
17:01Both branches have the unfortunate distinction
17:03of making the East African Rift
17:05the most seismically active rift system on Earth today.
17:09Thankfully, though, the majority of earthquakes it produces
17:11never really reach a magnitude of more than seven,
17:13and most are really predictable due to their tendency
17:15to happen near the Afar Depression.
17:18However, they of course still have the ability
17:19to negatively impact millions of people.
17:22Another concerning thing about the East African Rift
17:24is that it appears to be actively moving apart.
17:27You see, ever since the dawn of humans,
17:29the East African Rift has been splitting,
17:31and according to experts, at a rate of about 7 millimeters per year.
17:34While this was going on mostly unseen for a while,
17:37in 2018 it caused quite the scare
17:40when waterlogged ash that had been hiding in the splitting
17:43collapsed under heavy rains, exposing the split to the world.
17:47Thankfully, geologists believe that the split
17:49won't have any noticeable effect in our lifetimes.
17:52In fact, there will likely be no real consequences
17:54for the next few million years.
17:56However, once the splitting process really does get into full swing,
17:59things are going to get chaotic.
18:01You see, what's happening is essentially the same process
18:03as when Pangaea broke up and the Atlantic Ocean was formed.
18:07So, as the crack widens, it's likely that ocean water
18:10is going to come rushing in, splitting Eastern Africa
18:13and turning its easternmost flank into an island.
18:16Well, on a lighter note, the East African Rifts
18:18also produce some positives, too.
18:20The most notable is Mount Kilimanjaro,
18:22formed as a result of the active continental movement
18:25of the East African Rift.
18:26It's now a dormant volcano and the tallest mountain in Africa.
18:30When you further consider that other cool spots
18:32such as Mount Kenya, Mount Langanat, and the Meningai Crater
18:35were all created thanks to the East African Rift,
18:37it's not hard to see why this earthquake zone
18:40can also be a force for good.
18:43Number three, sunquakes.
18:46Just like on Earth, the sun can experience earthquakes.
18:50However, just like with Venus quakes,
18:51sunquakes don't come from below, but from above.
18:55While these also exist on Earth,
18:56after all, we're no stranger to fracking-induced earthquakes
18:59caused from pressure jets of liquid,
19:01what isn't clear is what the cause of sunquakes are,
19:04or more importantly, how the energy gets channeled
19:07to specific locations.
19:09What we do know is that when a sunquake happens,
19:11they release acoustic energy in the forms of waves
19:14that ripple along the sun's surface,
19:16much like waves on a lake.
19:18Then, in the minutes following a sunquake,
19:20a solar flare, which is an outburst of light, energy,
19:22and material, can be seen in the sun's outer atmosphere.
19:26For years, scientists have suspected that sunquakes
19:28are driven by some combination of magnetic forces
19:31and heating of the outer atmosphere,
19:32where the flare happens.
19:34These waves are thought to dive down through the sun's surface
19:37and deep into the interior, causing a sunquake.
19:40However, in 2011, new data
19:41from NASA's Solar Dynamics Observatory
19:43suggested something different.
19:45You see, on July 30th of that year,
19:47NASA spacecraft observed, quote,
19:49unusually sharp ripples emanating
19:51from a moderately strong solar flare, end quote.
19:54Upon further investigation,
19:56scientists were able to track the waves
19:57that caused these ripples back to their source
20:00via a technique known as helioseismic holography.
20:03Instead of the waves traveling into the sun from above,
20:06the scientists saw that the surface ripples of a sunquake
20:09emerged from deep beneath the solar surface
20:12right after a flare happened.
20:14In fact, the acoustic source of the sound
20:15appeared to be 1,100 kilometers below the surface of the sun,
20:19and certainly not above the surface,
20:21as previously thought.
20:23After putting all these findings together,
20:25the scientists concluded that these waves
20:27were probably driven by a submerged source,
20:29which, in turn, somehow triggered a solar flare
20:32in the atmosphere above.
20:33These new findings might also help explain
20:35a longstanding mystery about sunquakes,
20:38that is, why some of their characteristics
20:40look remarkably different from the flares that trigger them.
20:43However, while this is an exciting hypothesis,
20:46scientists still haven't identified
20:47exactly what mechanism actually causes sunquakes.
20:51In 2022, NASA conducted an experiment
20:53where they simulated a sunquake in a bid to figure this out.
20:57And more specifically, their work looked at
20:58how the sun responds to the energy released by solar flares,
21:02and how this corresponds to what we see in our observations.
21:05The idea was that this would give a better understanding
21:07of how energy is transported during a solar flare,
21:10and, in turn, help solve the puzzle
21:13of how they come into being.
21:14The results were surprising.
21:16While the scientists initially expected the flares
21:18that had more high-energy particles
21:20to generate the strongest sunquakes,
21:22this wasn't the case.
21:24Instead, since these high-energy particles
21:26are moving so quickly,
21:27they're more likely to travel through the sun's atmosphere
21:29without collisions.
21:31Instead, they found that the flares
21:32with more lower-energy particles
21:34generated the strongest sunquakes.
21:37Additionally, flares with lower-energy particles
21:39tended to generate strong acoustic gravity waves
21:41rather than normal pressure waves,
21:43further increasing their impact.
21:45When looked at in summary,
21:47this study suggested that a solar flare weak spot
21:50exists in terms of strength,
21:52allowing some flares to generate sunquakes
21:54while others don't.
21:56Yet, while this study certainly helped paint a clearer picture,
21:59the reality is there'll likely be more research conducted
22:02to truly figure out how sunquakes function
22:05or where they're most likely to happen.
22:11So, if you make your way over
22:12to the very western edge of North America,
22:14you'll find yourself facing what many consider
22:17to be the world's most powerful fault line.
22:19Extending for roughly 1,200 kilometers
22:21through the U.S. state of California,
22:23it forms part of the tectonic boundary
22:25between the Pacific Plate and the North American Plate.
22:28Traditionally, the fault has been classified
22:30into three main segments,
22:31the northern, central, and southern.
22:33Each has different characteristics
22:35and a different degree of earthquake risk.
22:37The northern segment extends from Cape Mendocino
22:39to the north, down south to Hollister,
22:41which is located within the Santa Cruz Mountains.
22:44The Cape Mendocino section is notable
22:46because it begins in an area
22:47known as the Mendocino Triple Junction, or MTJ.
22:51This is the point where the Gorda Plate,
22:53the North American Plate, and the Pacific Plate meet.
22:55This area is the start of the Cascadia Subduction Zone.
22:59This is easily one of the most dangerous
23:00subduction zones on the planet.
23:02After all, it's capable of producing earthquakes
23:04that are over a nine magnitude
23:06and tsunamis that could reach heights of 30 meters.
23:09The northern segment also passes through San Francisco.
23:12Now, the San Francisco Bay Area is notable
23:14because it contains several sister faults
23:16that run more or less parallel
23:18and can create other massively destructive earthquakes.
23:21The central segment goes between Hollister and Parkfield.
23:24It is by far the safest part of the fault line.
23:27That's because this section experiences a phenomenon
23:29known as a seismic creep,
23:30where the fault slips continuously
23:32without causing earthquakes.
23:34However, this seismic creep doesn't really make
23:36this section completely harmless either.
23:38That's because a seismic creep can produce
23:40a period of intense activity.
23:41The silver lining is that these periods
23:43tend to be pretty temporary in nature.
23:45Thankfully, scientists believe that due to advances
23:47in building codes and growing geologic knowledge,
23:50there's little to worry about here,
23:52although people in those areas should know
23:53that they're not immune to earthquakes.
23:56And the most southern section extends from Parkfield
23:58down to the Salton Sea,
24:00and it holds a middle position being neither most
24:02nor the least dangerous part of the fault.
24:04It's capable of producing 8.1 magnitude earthquakes,
24:07and it's got quite a bit of power.
24:09This is a problem because it passes just 56 kilometers
24:12northeast of Los Angeles,
24:14meaning it could cause some serious damage
24:17if an earthquake were to strike.
24:19There's also a lot of interesting scholarship
24:21surrounding the San Andreas Fault.
24:23It was first identified in Northern California
24:25by a UC Berkeley geology professor,
24:27Andrew Larson, in 1895.
24:29Rather than do what was popular at the time
24:31and attach his own name to it,
24:32he instead named it after the surrounding
24:34San Andreas Valley.
24:36As our understanding of plate tectonics evolved,
24:38we learned more and more about the fault line.
24:41To date, we figured out that the San Andreas Fault
24:43near Parkfield consistently produces
24:45a magnitude 6 earthquake approximately once
24:48every 22 years.
24:50The last such event happened in 2004,
24:52and now scientists have busied themselves
24:54estimating when the next big one will happen.
24:58A study published in 2006 in the journal Nature
25:00found that the San Andreas Fault
25:02has reached a significant stress level
25:04to produce an earthquake with a magnitude
25:06greater than 7.
25:07The study also found that the risk of large earthquakes
25:09may be increasing more rapidly
25:11than scientists had previously believed,
25:13and that the risk is currently concentrated
25:15in the southern section of the fault near Los Angeles.
25:18Yet despite this landmark 2006 study,
25:21nothing has happened in the 18 years since.
25:23This has caused scientists to take a deeper look
25:25and make their own predictions.
25:27For example, the U.S. Geological Survey's
25:29most recent forecast,
25:30which was released in November of 2013,
25:32estimated that there's a 7% chance
25:35that an earthquake of a magnitude 8 or greater
25:37will occur in the next 30 years
25:39somewhere along the San Andreas Fault.
25:42So, if you live along this fault line,
25:44I'd suggest staying up-to-date on the news
25:46so you can get a forewarning as early as possible.
25:50Number 1. Marsquakes.
25:53Just like on Earth,
25:54it appears that Mars has more
25:56than its fair share of earthquakes.
25:58And while the science on the subject
25:59was pretty sketchy for decades,
26:01in 2019, we finally found definitive proof
26:04that marsquakes exist
26:06and that there are fault lines on the Red Planet.
26:08The very first attempts to find seismic activity on Mars
26:11date all the way back to 1976
26:13through a project known as the Viking Program.
26:16As part of this effort,
26:17two landers were launched,
26:18the Viking 1 and Viking 2.
26:20Unfortunately for the world of science,
26:22the Viking 1 was an absolute failure.
26:25After landing, the seismometer on the Viking 1 malfunctioned,
26:27leading to no data being collected
26:30and making the spacecraft a dud.
26:32Thankfully, the Viking 2 fared a bit better.
26:34After spending 89 days collecting data,
26:36it recorded two possible marsquakes.
26:39However, that data was highly questionable.
26:41That's because the seismometer on board
26:43was extremely sensitive.
26:44So sensitive, in fact,
26:45that it reacted to everything
26:47from the rotation of the lander's cameras
26:49to the clicks of the tape recorder
26:51when recording data.
26:52Even worse, because of its unpredictable nature,
26:54the slightest gust of wind
26:56made the spacecraft platform vibrate,
26:58which again was picked up by the seismometer.
27:01Well, for years afterward,
27:02data collection surrounding Martian earthquakes
27:04was pretty limited.
27:06However, in 2018,
27:07interest in the subject renewed
27:09after the InSight mission
27:10revealed a massive collection of dust devils
27:12on the Red Planet.
27:14For those of you not well-versed in meteorology,
27:16dust devils are similar to tornadoes.
27:18And as such, there was a belief
27:20that if these natural disasters could exist on Mars,
27:23earthquakes could as well.
27:24On April 6th of 2019,
27:26scientists got the lead they were looking for
27:28when the InSight lander recorded
27:30what was believed to be a small marsquake.
27:33After more research was conducted,
27:35it was determined that the earthquake in question
27:37came from an area known as the Cerebrus Fausse.
27:40This is a series of deep gashes
27:41that linger about 1,600 kilometers
27:43to the east of InSight's landing zone.
27:46Then in 2021, a marsquake was recorded
27:49coming out of the Valles Marineris,
27:51proving scientists' suspicions
27:52that the area contained an active fault.
27:55In the years since then,
27:56even more fault-related recordings have been made.
27:58So it turns out that the way marsquakes are formed
28:01differs quite a bit from our earthquakes.
28:03You see, on Earth,
28:04quakes usually come from the never-ending movement
28:06of tectonic plates.
28:07This geological movement builds up stress
28:09in our planet's crust,
28:11and occasionally it hits a breaking point,
28:12causing land to suddenly shift
28:14and thus create an earthquake.
28:16On Mars, however, it doesn't have tectonic plates.
28:19Instead, it appears that after its formation,
28:21Mars was a searing mass of molten rock
28:23that eventually cooled to form a static crust
28:26around a rocky mantle.
28:28Ever since then, Mars' volcanoes
28:29have also fallen silent.
28:31This has led to scientists suspecting
28:33that marsquakes are formed by pockets of magma
28:35that linger below.
28:37More specifically,
28:38they're likely created as the planet's ongoing cooling
28:41and contraction cracks the surface,
28:43forming what we know as thrust faults.
28:45These findings are important for a few reasons.
28:48First and foremost,
28:49active fault lines on Mars
28:50prove that the planet is not geologically dead
28:53and that a lot of new movement is happening on it.
28:57While this is pretty cool in its own right,
28:58it also means that Mars is a pretty risky place
29:00for space exploration.
29:02After all, if strong enough,
29:03a marsquake could completely destroy space equipment,
29:06leading to millions if not billions of dollars
29:08worth of effort being destroyed.
29:10However, marsquakes also have a silver lining.
29:13Future human settlements on the red planet
29:15could potentially use Mars' faults
29:17as a source of geothermal energy.
29:20This in turn could help Martian settlements
29:22get to a point of self-sustainability.
29:25Well, in any case, Paul Byrne,
29:26who's a planetary geologist
29:28at North Carolina State University,
29:29notes that on balance,
29:31marsquakes are the least of our problems on the red planet
29:34as humans will have to make it
29:35through far more dangerous perils
29:37in order to create a successful settlement.
29:40Thanks for watching, everybody.
29:42I'll see you next time.
29:44Thank you to our channel members.