Underwater mountains, canyons hold secrets of Malaysia's seas

PORT KLANG: Beneath Malaysia's vast maritime waters lies a dramatic landscape of underwater mountains, ridges, valleys and canyons, much of which remains unmapped to modern hydrographic standards.

National Hydrographic Centre (NHC) director-general Rear Admiral Dr Najhan Md Said said understanding this hidden terrain was vital to safe navigation, maritime security and sovereignty.

"If you drain the water from the South China Sea, you will see a terrain just as breathtaking as anything on land.

"There are underwater mountains, massive ridges, steep trenches and ancient riverbeds that once ran above water thousands of years ago," he told the New Sunday Times.

Najhan also serves as the vice-chair of the International Hydrographic Organisation — Intergovernmental Oceanographic Commission General Bathymetric Chart of the Oceans Sub-Committee on Undersea Feature Names, comprising 12 international experts.

The sub-committee is responsible for establishing internationally consistent nomenclature and naming guidelines for undersea features, ensuring uniformity across nautical charts, bathymetric maps and scientific publications worldwide.

He said high-resolution bathymetric surveys had mapped extreme depths across Malaysia's maritime domain.

Seabed mapping, he added, shared some principles with astronomy, but also carried a strong connection to national identity and heritage.

"When astronomers discover a new star, individual scientists are often allowed to put their names on it. But under international maritime rules, individuals cannot name undersea features. That privilege belongs strictly to sovereign nations.

"To date, Malaysia has secured official recognition for 17 undersea feature names, most of them in the bathymetrically rich waters off Sabah and Sarawak," he said.

The New Sunday Times was provided with advanced 3D acoustic renderings from the NHC, showing the varied topography of some seabeds in Sabah and Sarawak.

Among them are the Santubong Seamount, a jagged, volcanic-like spire; Kenyalang Hill, with its sharp, conical summit; and the Rafflesia Hill, a massive dome-shaped mound.

Measured against the Kuala Lumpur skyline, the seabed's peaks hold their own.

Santubong Seamount rises about 1,400m from the ocean floor, roughly twice the height of Merdeka 118, the country's tallest building. Yet its summit lies about 500m below the surface.

Rafflesia Hill, at about 450m, matches the Petronas Twin Towers, while Kenyalang Hill, at about 320m, is 100m shorter than KL Tower (421m).

Rungus, Kadazandusun and Bidayuh Hills each rise about 900m, a third taller than Merdeka 118.

Submerged mountain chains include Iban Ridge, Bajau Ridge and Kimaragang Ridge, which stretch across the ocean floor.

The seabed also features deep chasms and valleys, including the steep-walled Meranti, Chengal and Anggerik canyons, and the broad, flat-bottomed Mawar Valley.

Najhan said naming undersea features has helped preserve Malaysia's cultural identity, with internationally recognised names documenting the country's heritage on global maps and in scientific records.

"Through ongoing high-resolution bathymetric surveys, the NHC has identified and prepared another 45 undersea features for formal registration and submission to the sub-committee on undersea feature names.

"Imagine looking at an international ocean gazetteer or a global map and seeing an underwater mountain in your home waters named in a foreign tongue.

"It feels like a personal sting to national pride," said Najhan.

He added that hydrographers had a duty to not only map the seabed, but also ensure its features bore the names reflecting Malaysia's history, culture and identity.