So what is seismic blasting anyway?

If you've heard the term “seismic blasting” bouncing around lately, but aren't quite sure what it means, here's the lowdown. 

Seismic blasting is essentially an underwater treasure hunt for oil and gas, except instead of a cute little map and shovel, companies tow a ship housing an array of high-pressure airguns to fire seismic shockwaves causing deafening blasts into the ocean every 10 seconds, day and night, for months on end.

And it's not just in one small patch of ocean either; these surveys can span more than 50,000 square kilometres — greater than the size of Tasmania.

Essentially, it’s loud and invasive, and it’s got a lot of people — scientists, fishermen, surfers and many others who care about the ocean — seriously worried.

The sound waves travel down, bounce off the seabed, and get picked up by sensors, creating a detailed underground map of potential oil and gas deposits. Useful for energy companies and fossil fuel supplies? Absolutely. Fun for marine life? Not so much.

So what’s the big deal?

First, the noise. Underwater, these blasts can hit 250 decibels — louder than a jet engine at takeoff and capable of travelling thousands of kilometres. 

Sound is the language of the ocean. Whales and dolphins navigate, hunt and find mates through sound — imagine trying to hold a conversation while someone sets off dynamite in your house every few seconds. Now imagine your life depends on that conversation.

Then there’s the collateral damage. It’s not just whales and dolphins — zooplankton, the tiny creatures at the base of the ocean food chain, get absolutely hammered.

Research from 2017 found that a single airgun blast could wipe out plankton populations over a kilometre away. No plankton means big trouble for fish, seabirds and basically everything else that relies on them — so the entire ocean food chain, essentially.

Otway blasting

Here in Victoria’s Western District, the Otway Basin — the stretch of ocean between us and Tasmania — has been a hotspot for seismic testing proposals. Companies have eyed this area for years, but they keep running into one big problem: people aren’t having it.

These surveys aren't illegal — they're signed off by the National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA), Australia's offshore energy regulator, who requires companies to submit Environment Plans showing their environmental risks are at acceptable levels. This includes assessing impacts on marine life and implementing mitigation measures like exclusion zones and timing restrictions. While NOPSEMA acknowledges these blasts impact the environment, they consider the damage "manageable" with these safeguards.

In 2024, energy firm TGS backed out of what would've been the largest seismic testing survey ever in Australia after more than 30,000 submissions opposing the plan flooded NOPSEMA. This, along with hundreds of people turning out in person to protest across Victoria's southwest coast, sent a clear signal - the locals do not support this.

But that victory was temporary. Another company, CGG, has been pushing for a new round of blasting off the coast of Warrnambool and the Logans Beach whale nursery. And with endangered species like the pygmy blue whale and southern right whale frequenting these waters, the stakes are high.

The protests are ongoing. Most recently, the "Seismic Shift" protest at Warrnambool’s Logans Beach on Saturday, March 29 saw more than 1,000 people gather — locals, surfers, conservationists, First Nations groups and environmental organisations were all there in solidarity against seismic blasting in the region.

What’s next?

The science isn’t great for seismic blasting. Evidence keeps piling up that it harms marine ecosystems, and public opposition appears to be growing. 

Meanwhile, the energy industry argues these surveys are essential for finding new reserves — even as the world tries to shift away from fossil fuels. 

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