It is an unfortunate
fact that the very same fault line which caused the
December 26th 2004 tsunami, where the Eurasia plate
pushes over the Australia plate, runs just south of
Bali. It is also a chilling thought that Bali's main
tourist areas are just 20 minutes away from a similar
tsunami should a similar earthquake occur in the wrong
place. But what makes this even more worrying is that
some experts in Europe have indicated such a quake may
be long overdue and perhaps hastened by the extra tension
created between the plates just off south Sumatra, Java
and Bali by the December 2004 disaster. You see, after
the December 26th quake that caused the killer tsunami
across the Indian Ocean, virtually all of the aftershocks
happened to the north of the main quake's epicenter.
Aftershocks are where smaller quakes occur elsewhere
along the main and neighboring fault lines to give off
the extra tension caused there by the main quake. So
it is probable that extra tension, unrelieved by aftershocks,
has built up along the Sunda Trench (fault line) to
the south.
Bali and potential visitors to the island have been
lulled into a false sense of security by the fact the
island was untouched by the December 2004 tsunami, by
token of the fact it was shielded by Java and Sumatra
(the large X marks the epicenter, so you can see this),
and by the unsubstantiated optimism of both the Indonesian
Government and tour operators / travel agents that it
could never happen to Bali. There has even been talk
of implementing the tsunami warning system used elsewhere
in the Indian and Pacific Oceans. But this would not
help Bali during a local event, as it is just 20 short
minutes by tidal wave away from the fault line. This
warning would only help other countries, further away
get advanced warning.
Anyway, there would be no siren alarm needed if a major
quake happened along the Sunda Trench just south of
Bali. Anyone and everyone on Bali would feel such a
quake and how. The damage to buildings erected without
any strict building codes would likely be considerable.
The irony being, those that were flexible enough to
survive the quake would almost certainly not have the
constructed strength, by default, to withstand an incoming
tsunami if they are near the beach. Anyway, even if
we assume there was not utter devastation from the quake,
getting away from any resulting tidal wave would be
a major problem for people in the low lying tourist
areas close to the ocean. You see, the largest wave
that hit Aceh (nearest to the quake) on December 26th
2005, was some 30 meters (100 feet) high. Tidal waves
as high as 60 meters have been known. To put this in
proportion, a London double decker bus is 4.2 meters
high. For many buildings, 30 meters equates to 7 storys
/ floors. It is perhaps ironic, due to Bali's regulations
for building heights, that no building can be higher
than a coconut palm tree. The maximum height of a coconut
palm tree is 30 meters, although most are much smaller
of course.
Experts in Europe have predicted further quakes in
the area, and were confirmed as accurate by further
quakes along this fault line on the 28th March (8.7
on the Richter scale) and 8th June (6.3 on the Richter
scale). Optimists will point out that it takes a large
and very specific kind of quake under the sea to generate
a tsunami. A quake above 9 on the Richter scale where
the sea bed is raised by 15 meters or more. Unfortunately,
the Sunda trench is a fault line that causes mostly
vertical movements in the earth's crust, as one plate
rises above another. Other fault lines, as you can see
on the above image, such as the Sumatra fault (which
runs parallel to the Sunda Trench fault) are lateral
faults. That is they move in opposite direction and
grate against each, not move above / beneath each other.
So whatever magnitude of quake happens along the Sunda
trench will almost certainly result in the sea bed being
raised. And the fact is, the Sunda trench is a major
fault line and well capable of producing 9+ Richter
scale quakes.
Some may well say this page is not fair on the Balinese
/ Indonesians, as it is not something they are guilty
of or can easily solve. But we believe the Indonesian
Authorities should produce Earthquake, Volcano (Bali
has 2 active ones) and Tsunami education information
sheets for tourists. More stringent building codes would
certainly help too. So in lieu of this, how can you
avoid and / or protect yourself and earthquakes while
on Bali?
Earthquakes
First, find a strong structure such as a heavy table
or doorway to protect yourself under. Do not run out
into the street unless you have no choice, as you are
more likely to be injured from falling glass and debris.
Once the quake is over, immediately move to a safe area
if you can to avoid the risk of gas leaks, further quakes,
etc. Avoid beach areas or areas with weak soil, as strong
quakes may turn these into quicksand. If you suspect
the quake was out to sea and significant enough, try
to make your way to higher land / inland to avoid any
resultant tsunamis.
Tsunamis / Tidal Waves
To lessen your chances of being affected by a tsunami,
stay at a hotel at least 50 meters (160 feet) above
sea level or 3.2 kilometers (2 miles) inland from the
beach. Or stay in a beach area sheltered by land mass
from the potential wave source. Although these sheltered
beach areas are likely to experience some flooding if
the land mass is not that great; as what happened on
Koh Phi Phi and Koh Phuket in Thailand, the sheltered
side of the islands experienced some rising water).
The main tourist areas in Bali most at risk are Jimbaran
Bay, Kuta, Legian, Seminyak, Tanjung Benoa, Nusa Dua,
Sanur and Candi Dasa. As they have low lying beach areas
which directly face the Sunda trench.
If you believe a tsunami is imminent, chose whichever
is the most available option;
a) Move as quickly as possible inland and / or to higher
ground.
b) Get to the top of the tallest building you are able
or climb the nearest tree.
Please do not become a victim or part
of the problem. Read:
Bali
Tourism (Should I go, where, and how do I avoid
adding to the problem / putting myself / my family at
risk in Bali?).
|