The Market Monitor Minding the Nation's Business
By Rose de la Cruz
With global warning attributed mainly to greenhouse gases like carbon dioxide, adding to carbon emissions like alternative fuel laden with CO2 harmful to the environment.Just as carbonated drinks are water infused with carbon dioxide, so are gas hydrate that are mostly ice infused with methane are good as fuel but dangerous to the environment.
Gas hydrates are ice-like substances that usually form beneath the seafloor, where the pressure is high and the temperature is just below the water’s freezing point of 0°C.
The UP Diliman College of Science Natonal Institute of Geological Sciences found that gas hydrates may be abundant in the Manila Trench, west of Luzon.
Scientists Elisha Jane Maglalang, Dr. Leo Armada, Madeleine Santos, Karla May Sayen, and Dr. Carla Dimalanta of UPD-CS NIGS made a pioneering study on these substances in the Philippine trenches where they found that since gas hydrates have huge amounts of carbon and methane, they can be great alternative energy sources.
“The western Philippines has vast potential for this unconventional energy resource, with a total area of 5,400 square kilometers in the Manila Trench, or the size of Palawan, containing gas hydrates. They estimate these substances might be around 200 to 500 meters below the seafloor.
But, they said, gas hydrates pose geologic and environmental threats as they are unstable solids that would dissociate and melt when the conditions in which they form change, usually during earthquakes.
The Manila Trench is an active margin, responsible for numerous earthquakes in Western Luzon. When gas hydrates melt, it will agitate the seafloor, possibly triggering submarine landslides and tsunamis.
Moreover, methane can harm the environment when released into the atmosphere. Methane is a potent greenhouse gas that contributes to global warming, and just one cubic-meter block of gas hydrate contains as many as 160 cubic-meter blocks of methane in its gas form. This is equivalent to 14% of an average Filipino’s methane emission in 2021, they said.
“Therefore, it is essential to determine the distribution and stability conditions of gas hydrates offshore of the Philippines,” the researchers emphasized.
To determine their location without drilling through the seafloor, scientists rely on sound waves. Similar to how a pond reflects sunlight, gas-bearing substances like gas hydrates reflect sound waves. These seismic reflections, called bottom-simulating reflectors (BSRs), indicate where gas hydrates might be present. By analyzing existing seismic data in the Manila Trench, they were able to map out BSRs and, consequently, deduce possible locations of gas hydrates in the region.
They note, however, that while BSRs are tell-tale signs of gas hydrates, they are not definitive. “Future drilling of offshore targets will be instrumental in confirming methane hydrate occurrence,” they said adding that “these investigations offer a vital opportunity to develop our indigenous energy wealth.”
Moving forward, they are conducting additional investigations in other offshore places in the Philippines to expand our geophysical dataset. The team is spearheading efforts to foster marine geophysics in the country. ”These efforts will contribute not only to the advancement of scientific knowledge but also to the development of the expertise of Filipino geoscientists in marine geophysics,” they concluded.