Semengerikan Apa Simulasi Gempa Megathrust di Jawa?

There is a giant fault line that

stretches thousands of kilometers in southern

Indonesia. This line looks still,

but it is actually holding the energy of

thousands of nuclear bombs.

Every year the plate beneath Indonesia

continues to move just a few centimeters. It's so

small it doesn't feel like it. But when

that movement is locked and stopped for tens

to hundreds of years, if it is released

in one [musical] beat, the

result is not just an earthquake. This could

turn into a tsunami tens of

meters high. What's more frightening, some

segments of this fault haven't ruptured for a long time

, much longer than they should.

Researchers found that at

certain points the sea could rise

by 20 or even 30 m in the

worst-case scenario. Not a movie, not a theory. This is

the result of a scientific simulation from the

latest research.

And this is where everything changes. We

are sitting atop one of the

most active mega trust zones in the world.

Just one incident, in just a matter of

minutes, was enough to change the face of

southern Indonesia.

[music]

So far we have only seen the Java Sea

as a calm blue line. No

one expected that right

below them the researchers would find something

much more serious than they

had imagined. In the last 5 years

a series of new studies have emerged,

published in journals from Nature NHS

to Springer, that reveal

disturbing patterns. There are segments of Megatras

that should have already released

their energy. That means triggering a

large earthquake to bring the pressure back to

normal. In fact, he is still silent until

now.

Silence is not good news. Silence is actually

a sign that the stored pressure

has exceeded normal limits.

And all the cities along the coast

from Sukabumi, Pangandaran, Cilacap,

Yogyakarta to Pacitan stood right

in front of the stage. This is the reason

why this simulation is important. Not to

scare you, but to understand

what [music] happens when a

long-locked fault

finally moves. Because before all

that can happen, we need to know first what is

actually waiting under the

sea.

[music]

Beneath the seemingly calm sea, there is

a giant boundary where two

earth plates meet. That's where Sunda Megatras

is located. The fault is over

5,000 km long and moves very slowly,

only a few centimetres per year.

Slow movement, but the power

it carries is not something to be

underestimated. Every year the

Indo-Australian plate continues to push

northward trying to subduct under the

Jurassic plate. But not all of the urges were

successfully released. At some point

researchers discovered that

these two plates were locked. This means that

the surfaces are held together, not

moving, and the pressure continues to build up

silently. This condition is called the

lock zone. And according to several

recent studies, including research by

Spinger and analysis of the makeup seismograph, the

locked segment of southern Java has been

storing energy for too long, longer than is

considered normal in a large earthquake cycle

. When a locked zone

holds pressure for tens to

hundreds of years, the earth doesn't just let it go

. The pressure that continues to strengthen

causes the locked part of the plate to

slowly bend like a bow that is

being pulled further and further. And the further

it is pulled without releasing, the greater the

force will be released when it finally

breaks. This is where the

scientists' discomfort begins. They see

signs that certain segments

in southern Java, especially those

stretching from West Java to

East Java, are in a critical phase.

Not because it was moving, but

because it had been stopped for too long.

In his statement, he also asked, if

this much energy were released in one

incident, what would actually

happen to the coastline that

we have always considered safe? The

next chapter will take us to the

first second when that scenario

actually happened.

[music]

All Megadra simulations always start

from the same moment. The moment when the

locked zone finally broke. There was no

big sign, no light, just a

low sound from deep within that was

inaudible even to humans. Then

the earth moved. In the scientific scenario

created by researchers, the

large earthquake in southern Java is likely

to have a magnitude of 8.7 to 9.0.

Not a random number, but a calculation result

of how wide the fault area

can break at once.

As soon as the segment that had been locked for hundreds of years was

released, the land above it

immediately rose rapidly in a

very short time. Just a few tens of

seconds. But its energy is greater than

all the nuclear bombs ever tested by

humans. On land the vibrations were not

like ordinary earthquakes. Simulations

show the shaking could last 2

to 4 minutes. Long enough to throw

people off balance

before the building even starts to collapse.

Street lighting is out.

Communication networks collapsed. In some

coastal areas, the land can sink several

centimeters permanently as parts of the

island are pulled by plate movements.

What is rarely discussed is the

hidden part of vertical displacement on the

seabed. This is not a shear fault that

just moves sideways. The

Megathrust fault pushed part of the seabed

up, part down, and

the elevation changes happened in a matter of

seconds. This movement was the beginning

of something far more dangerous

than the shock itself. A

large wave that begins to move towards the shore

without being visible from the surface.

And this is the critical point. In each

simulation, the Megathrust earthquake was not

climatic. It's just an opening. The

deadliest part only began after

the earth fell silent again.

[music]

When the tremors stopped, many people

thought the danger had passed. Yet it was at that

moment that the real threat

began to form. As the seabed

rises several meters in a matter of

seconds, the water directly above it

rises with it. forming a giant cuba

that is invisible from the shore. Cuba

is the beginning of the tsunami. It began

to spread in all directions, carrying energy

that exceeded the speed of a

commercial airliner.

Simulations from various studies

show that waves can

reach speeds of 700 to 900 km/h

while still in the deep ocean. At

this point, the wave doesn't look

like a wall of water, but just

like the sea level has risen

a few tens of cmer. This is what

makes it dangerous, fast, silent, and

invisible from a distance. However,

everything changed as soon as the waves

approached land. The shallowing of the sea depths

forces the enormous energy

to rise. Its height is no longer a few

cm, but can reach 10 to 20 m.

along most of the coastline and in

some locations with certain contours

such as Capes, Narrow Bays, or

Steep areas. Its height could

soar more than 30 m according to the

worst-case scenario calculated by

researchers.

The areas hardest hit in

this simulation were along the

southern coast of Java, southern Sukabumi,

Pangandaran, Celacap, Kebumen to

Pacitan.

In these places, the first wave is

usually not the highest. In fact, it is the

second or third wave that

carries the greatest power. It came

after people started coming down from

high places because they thought the danger had

passed. And it all happened in a

very short period of time. In many

places, a tsunami can reach the coast

in just 20 to 30 minutes after a

major earthquake occurs. Too

little time to wait for a

long warning, but enough if people

knew which way to run. It is in

these minutes that life or death

is determined not by who is

the strongest, but by who is the

quickest to understand [musically] what is happening.

[music]

As the first waves hit

land, the simulation showed something

hard to imagine. It wasn't just water

that came in, but entire city structures

that were swept away in a matter of seconds.

Streets, houses and even vehicles

parked along the coast turned

into debris carried by the current. In

some areas, such as Pangandaran and the

coastal areas of Cilaca, the waves could

penetrate deep into hotels,

restaurants and densely populated residential areas

before losing their power.

Simulations from the Batu Karas study and

some modeling in Cilaca

show that the most fragile parts

of Java's southern coast are actually the areas

most familiar to tourists. The gently

sloping, low-lying beaches

that are beautiful on sunny days

turn into perfect entry points

for tsunamis.

The wave did not come as a

single blow, but a series of

impacts carrying large amounts of debris.

Every dollar carried along

increases the destructive power of the

next wave.

But the impact doesn't stop at the

beach. In Cilacap, a large oil refinery

that is one of the pillars of

national energy is located very close to the

coastline. In extreme simulations,

damage to this area not only

triggered fires, but also

stopped energy distribution to

parts of Java.

Likewise, ports,

industrial areas and power plants are

spread along the south of the island.

When these cities are paralyzed, the impact

ripples throughout the national economic system

. Transportation stopped,

logistical supplies were cut off, and energy networks

were disrupted.

Then, what about the

psychological burden? Survivors of the

first wave still had to fight their way

to high ground. Meanwhile the

second and third waves continue to arrive.

Many evacuation routes on the south coast of

Java have actually been mapped

in various studies. However, access

to safe points is often blocked by

buildings, narrow roads, or

unknown to local residents. Ultimately

survival is determined by

decisions made in the

first minutes after the earthquake stops. At

this point, the war is no longer between

humans and water, but between humans

and time. Because once the

third wave recedes, what remains will not only be

physical damage, but a city that

will have to rebuild itself from the

ashes. [music]

Sunda Megatrans is not a myth. It's not a

prediction, nor is it a fear

spread by the internet. This is

part of the earth's mechanism that works

deep beneath our feet. Slow, quiet,

but sure. Every study that has

emerged in the last 10 years has only

reinforced one thing. Tekanan di zona ini

ada dan suatu hari nanti tekanan itu

akan dilepaskan.

The question is no longer whether a

major earthquake and tsunami could occur, but

how prepared we are when the time

comes. Because the Megat Trans disaster is not an

enemy that can be stopped. All

we can do is increase our

chances of survival by understanding what's

happening, recognizing evacuation routes,

and not waiting for the sirens to

decide to move.

Indonesia has repeatedly

proven that we are capable of recovering

from natural disasters. But getting up is always

harder than getting ready. So

before the wave actually appears

on the horizon, before the long tremor is

felt on our land, it is good for

us to ask. Do we know

where to run when the earth finally

speaks?

[music]

Yeah.