Monday, April 22

For whom the bells toll in Sulawesi

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A man gestures towards a search and rescue team while looking for victims in the earthquake and liquefaction affected Balaroa neighbourhood in Palu, Central Sulawesi, Indonesia. — Reuters photo

IT was with great surprise that, a week after I returned from the active volcanic island of Vulcano, Sicily, I found that travel insurance can now be purchased, as an “add on” cost, to cover volcanic eruptions, earthquakes and tsunamis to include medical treatment and evacuation.

At 2.49 pm on Friday (Sept 28), the island of Sulawesi was shaken by a major earthquake of a magnitude of 7.5. Balikpapan in Kalimantan, Borneo, just 286 kilometres southwest of the earthquake’s epicentre, also experienced the tremor.

A destroyed road is seen in Balaroa neighbourhood hit by an earthquake and ground liquefaction in Palu, Central Sulawesi, Indonesia. — Reuters photo

The harrowing images, as televised, of the total disaster that hit the central province of Sulawesi island have said more than words can even begin to express. Where there is a need, there is a will and fortunately the world, for once, has pulled itself together in international aid programmes.

Where is Sulawesi?

If you said to me the two words Makassar and Celebes, then these would have clicked in my mind. The Celebes was the former name of this island until 1947 and Makassar is its capital.

In my boyhood days, I can well remember my mother placing linen drapes known as ‘anti-macassars’ over the back of all chairs in our household, much the same as most airlines today place disposable paper or synthetic linings on head rests on passengers’ seats.

In the mid-20th century, men used to ‘slick’ their hair with oil of Makassar, leaving stains on the fabric of chairs!

Sulawesi is just to the east of southeast Kalimantan and shaped in ballerina stance form with the left arm held upwards in an arc, the right arm extending upwards in the air, and with the left leg on toe tip and the right leg in the air to counterbalance the posture – almost like the letter K with four peninsulas! It is the eleventh largest island in the world.

What actually happened in Sulawesi?

Indonesia possesses five per cent of the world’s volcanoes with a string of these in Sulawesi.

Mount Soputan became active only four days after the earthquake, spewing out volcanic ash, nearly five kilometres up into the atmosphere, thus causing restricted aircraft movements.

A motorcycle passes in front of a stranded ship in the port hit by tsunami on the coastline in Palu, Central Sulawesi, Indonesia. — Reuters photo

Some 80 geological fault lines run through Indonesia and it was along the Pulakorn fault line that the big earthquake occurred. A month or so before that fateful day, as many as 20 to 30 smaller tremors each day had taken place.

Indonesia possesses a very complex tectonic environment, lying at the collision point of the Australian and Eurasian continental plates and the Philippines oceanic plate. Over millions of years of collisions, microplates have been created there.

In the so called Sunda volcanic arc, stretching for 3,000 kilometres, two or three strong earthquakes of a magnitude of seven and over are recorded annually.

The Palukorn fault experienced a strike-slip event in the interior of one of the microplates. The rocks to the east of this fault running through Sulawesi moved northwards relative to the surrounding rocks.

In doing so, this movement triggered a landslide of the underwater seabed sediments, thus causing a sudden vertical displacement of seawater, thrusting the surface waves to travel at a rate of 700 to 800 kilometres per hour.

The epicentre of this earthquake was only 39 kilometres below the surface of the seabed, just 78 kilometres north of the disaster that quickly befell the 363,000 plus residents in the regional capital of Palu. Subsequently, many aftershocks of a magnitude of between six and seven have been felt.

The ensuing tsunami

Palu lies at the head of the River Palu estuary with the town of Donggala to the north east near the Makassar Strait. The Palu river valley and its estuary stretch finger-like towards the open sea, lying along a fault line.

The giant earthquake created shockwaves and displacement in the seawater which traversed the Makassar Strait, entering the Palu estuary.

With all tsunamis, the shape and depth of the seafloor together with the configuration of a coastline play an important part in determining their force and timing when hitting coastal areas.

Moving along the Makassar Strait at high speed, the seawater waves were refracted by the shape of a headland and ‘piled up’ because of the shallower water in the Palu estuary. Thus, the waves’ speeds decreased but their heights increased to six metres before breaking and crashing down onto the shoreline of that city.

There is no doubt the elongated configuration and deep water in the Palu estuary were major factors leading to the devastation wrought there as the waves became amplified.

Coastal villages in depths of despair

Media attention has focussed on Palu where the tsunami ripped through the city, destroying the central mosque and its people at prayer.

Buildings crumbled and large ships in the bay were ripped from their anchorages and swept inland. Jetties were broken into smithereens under the force of the waves’ impact and containers were tossed around inland as if they were match sticks!

Over 1,700 people have been declared dead, with 5,000 people yet to be accounted for. Temporary makeshift hospital field tents house 2,570 patients with serious injuries.

With their houses totally destroyed, 70,000 to 80,000 people, as victims of this tsunami, are spread over 150 evacuation sites. Prisoners escaped as the jail walls crumbled.

What of the devastation in remoter coastal areas?

Massive landslides and mudflows, caused by the liquefaction of soils in mountainous areas, have cut off roads and communication masts from rescuers. Sadly, the death toll will rise and the number of homeless persons will continue to increase. Only time will tell.

The regional airport at Palu, which suffered runway damage by the earthquake, was inundated with refugees trying to get to relatives in Makassar but now, it is only open to emergency flights bringing in fresh water supplies and food.

Just imagine living in the 21st century without a home, fresh water, food and with no means of communication! That is the Armageddon situation on Sulawesi.

Aid pouring in

The Indonesian government has flown in military aid in terms of doctors, nurses, engineers, soldiers, communication experts and machinery, together with its own search and rescue teams.

The world at large has responded by raising over IDR 250 billion of economic aid and direct aid. Japan, for instance, immediately responded to the call in despatching experienced emergency, earthquake and tsunami rescue teams.

Many, mostly unidentified, victims, have already been buried at the Poboya Cemetery in Palu. The world’s prayers in all mosques and churches have been with the victims of this tragedy, with religions and NGOs all over the world providing financial assistance and emergency aid.

Could more have been done to avert the devastating effects of this particular very forceful earthquake?

The answer to this question is simply NO.

Sophisticated early warning systems do exist in Japan and Hawaii, but trying to replicate such systems in the Indonesian archipelago is well-nigh impossible frankly, because of the multiple languages spoken throughout the islands.

That said, several emergent Indonesian agencies have tried to develop sophisticated earthquake and tsunami disaster warning systems but, alas, their annual budgets have been cut.

Indonesia does have land-based seismographs and, around its coastline, very costly sensors on the seafloor which transmit warnings to over a score of floating buoys to satellite links. It also has a tsunami warning network of over 130 tidal gauge systems and warning sirens in well over 50 locations.

Clearly, no system of communication from satellites back to Earth receiving stations could have alerted the inhabitants of Sulawesi fast enough as the earthquake destroyed the main telecommunication masts and outlying stations on that island.

Given time, the real geological reasons for the earthquake and its resultant tsunami and inevitable tragedy on this island will emerge. Time is a great healer so it is said, but memories will stay for a lifetime for those who have survived this horrific disaster.

The name Palu is derived from old Malay meaning in translation “hitting hard with a rigid weapon” – this tsunami did just this!