Marking 20 years
of bold journalism,
reader supported.
Science + Tech

Inside the Quest to Chart the Seafloor by 2030

A Tyee Q&A with Laura Trethewey about her new book, ‘The Deepest Map.’

andrea bennett 4 Sep 2023The Tyee

andrea bennett is a senior editor at The Tyee and the author of Hearty: Essays on Pleasure and Subsistence, forthcoming with ECW Press.

What compels people to uncover the mysteries of the deep sea?

In her new book The Deepest Map, ocean journalist Laura Trethewey documents the race to map the seafloor — by the year 2030, if the ocean-mapping project Seabed 2030 has anything to do with it.

Tomorrow, we will feature an excerpt from the book, following Trethewey’s search to join an ocean-mapping vessel and experience first-hand how it gathers its data.

Today, we ask Trethewey all our burning questions about ocean science, gender dynamics in ocean mapping, and why humans as a species can’t simply leave the ocean alone.

This interview has been edited for length and clarity.

The Tyee: I’m going to get my naive and ornery question out of the way off the top: why not just let the ocean have its mysteries? Why do we want, or need, to map the ocean?

Laura Trethewey: There was a really great tweet that somebody put out. I don't know who they are, or where they came from, or what they have to say about oceans, really. But they said something along the lines of like, “95 per cent of the ocean is a mystery. Good, leave it alone, it's haunted.” I think about that tweet all the time.

We have such a history of uncovering new frontiers and not treating them very well. I think it's a really good question to ask, and it was definitely a question that guides the whole book. What is the point of doing this? What are we going to be using it for?

After all of my worries in the book about deep sea mining and other extractive industries that are taking off in the deep sea, I still found myself getting sucked into the wonder at times, particularly when I was out on ships. I would be with scientists or researchers, and they would just be showing me something really cool about the world that I never knew existed.

In the part of the book that you’re going to excerpt, I accompanied a deep sea mapping trip, and one of the projects was investigating forams, which are microscopic organisms that are over 500 million years old. They’re beautiful under a microscope. They kind of look like tulips. There is something kind of heartbreaking about the idea of not knowing about forams, about not knowing about these amazing secrets of the world.

Some people look at the ocean and they’re there to extract things from it. But then there are also a lot of people there who are really drawn to the discovery and the beauty of it.

Correct me if I’m wrong, but there are sort of two camps of people in your book who are interested in deep sea mapping: scientists, and people who are essentially contemporary gentleman explorers who want to visit the depths of the sea to satisfy a desire to be in a place no human has ever been before. Are there tensions that emerge between these two camps?

There are a lot of groups out on the ocean. Those two groups are probably the ones that are the most famous and that you would think of when you think of ocean exploration. But they're definitely not the only groups out there. It’s a pretty motley crew of people, which was something that was so hard to capture in the book. But to answer your question, yes, there has been this tension between those two groups growing over the last 20 years or so.

For a long time, ocean research has been underfunded. Academics have had to make do with, well, crappy ships or not very much support, or whatever it was. And then there were a couple of devastating reports that came out about ocean health. And then all of a sudden there was a lot of money coming into the field, from billionaires and millionaires who wanted to help the ocean. But then there was also a lot of skepticism about what they were doing there. Were they there to burnish their legacy? Were they there to actually do good science?

The book kicks off with Victor Vescovo. When he comes into this world, he wants to dive the deepest points of all five oceans. A lot of the scientists on board were really skeptical of him at first, I think with good reason, because diving the deepest points of all five oceans is a bit of an arbitrary goal scientifically. The scientists were really concerned: what is the point of doing this? In Victor’s case, I think he did come out to be a good supporter of science and showed himself to actually be interested in the ocean beyond record chasing.

But there is still this tension between who has money and who doesn’t, in exploring the ocean.

How much of ocean mapping is related to the prospect of extracting value from the ocean via deep sea mining, or oil and gas?

I don't have an exact number for you, but probably most of it. Seabed 2030 has a lot of partnerships with various companies all over the world. They’ve made certain partnerships with petroleum companies that are out there sounding the seafloor. They also recently partnered with the International Seabed Authority, which is the regulator of deep sea mining. Whenever the industry does take off, Seabed 2030 and the authority have some kind of map-sharing partnership.

It gradually became clear to me while I was writing the book. I thought the academic mappers had all the maps, but it became clear that they were actually the ones asking other people for maps. They are really reliant on militaries and industries. The academic expeditions that happen are tiny compared to the commercial ones.

What were you thinking about when you heard the news about the Titan submersible? The predominant narrative surrounding its implosion was about the hubris of the OceanGate CEO in terms of his belief that regulation hindered innovation. And then I read your book, and now it sort of feels to me like a lot of expeditions to the bottom of the ocean involve submersibles that, say, leak and have parts that accidentally fall off. Is the entire project a project of hubris?

Since the news of the Titan submersible implosion, there have been a lot of people on the news who have done some dangerous dives in their time, who have been like, "Well, I would never" — you know, quite judge-y.

This is an industry populated by mavericks and cowboys. It’s a lot of men out on ships sending things to the bottom of the ocean. There’s a lot of machismo on those ships still. There’s a lot of risk-taking.

That said, Stockton Rush did not have his submersible certified by the leading industry expert group. That did make him an outlier. Victor Vescovo paid about half a million dollars to get that certification. So there’s a lot of risk-taking in this field, but eventually somebody is supposed to come in and make sure that this thing can actually do what it's supposed to do.

That was a really crazy week when they were looking for the submersible. I was pretty certain that the people on board were dead. A lot of the online commentary was very vulgar and really crass around the human lives that were lost. There were also totally worthy criticisms about how much money and effort was spent on the search, particularly in comparison to what happened with the migrant ship that sank around the same time.

I’d heard warnings about OceanGate expeditions while I was writing the book. I went back and listened to some of those interviews. People were straight up telling me that someone was going to die on that expedition. At the time I would be like, "Okay, interesting." And I would move on. And then I listened back and I was like, oh my gosh, they were telling me right there that somebody was going to die, and it didn’t really sink in until it finally happened.

My colleagues were excited that I was going to be speaking with you. One question that emerged from a few folks: is there a possibility that deep sea exploration will lead us to learning about species we’re not yet familiar with? Importantly: how big might they be, and will they want to eat us?

I’ll handle the funny, cute part first. No, they’re not going to eat us. They tend to be like quite small organisms, or, you know, snails or clams, those kinds of things.

But yeah, there are tons of animals that are being discovered all the time. That’s why I’m still on the side of ocean exploration, even at the risk of exploitation. Because there are so many animals that we don’t know about down there. And I think they deserve to be discovered and known and their beauty brought into the world.

The mining companies that go out to the Clarion-Clipperton zone, which is that big area in the Pacific that they’re thinking about mining — scientists go out there and they lower down these box cores that sink into the sediment and bring up animals preserved in situ, and every time they do that, they’re bringing up animals that they haven’t known about before.

A study came out recently just about the Clarion-Clipperton zone, where scientists went through all the literature about the animals found in that area, and they found over 5,000 animals, just from that zone, with about 90 per cent that had never been described or known by science. There’s just so much more work to do. Every time somebody goes out there, they discover a new animal.

It’s also changed our fundamental understanding of biological rules on Earth, right? We’d previously thought that all animals on Earth relied on photosynthesis to some extent, and then we found —

And then we found chemosynthetic environments, yeah. Animals that survive off chemicals. That happened in 1977. Bob Ballard, the same guy who later discovered the Titanic, was part of the crew that discovered hydrothermal vents and changed our whole understanding of how life works on Earth.

There were so many moments in the book that were surprising to me — it’s a rollicking read. The moment that’s seared into my brain is when Victor Vescovo finally descends to the bottom of the Puerto Rico Trench, ostensibly in a spot no human has ever been before, and then he sees a cracked oil drum at the bottom of the ocean. And to surface, he has to jettison weights on his submersible — leaving more waste at the bottom of the ocean. What surprised you, as you were researching and writing?

I remember being really surprised that Cassie Bongiovanni, the ocean mapper on board the Five Deeps Expedition, was the first person to discover the deepest points of all the oceans. I was really surprised that no one had done that before. And also that when she did it, there wasn’t more fanfare about it, because I thought that it was a really interesting accomplishment.

It mirrors Marie Tharp I guess — the fact that her maps weren’t celebrated until the end of her lifetime. Is there a gendered dynamic in terms of mapping the ocean, in terms of who gets the fanfare? Because I feel like Victor Vescovo certainly got more fanfare for going down to the deeps.

Yeah, there’s that ongoing gender dynamic that the man kind of goes out and discovers, while the woman puts the data together, and tells you where to go. I get it to a certain extent. Victor Vescovo, if he hadn’t put that money in, if he hadn’t put the whole crew together, that trip wouldn't have happened. You do need a sort of Vescovo-like figure to get the thing going. But there’s definitely not enough attention paid to the people who get you down there. I love those people. I love anybody in the trenches, working away. I wish more Hollywood movies were made about, like, government bureaucrats.

When the Seabed 2030 project started in 2017, about 15 per cent of the ocean was mapped. As of 2022, when you were writing your epilogue, the project had reached 23.4 per cent complete. Do you think the project will hit its goal?

Ummm… yeah, probably not. Seabed 2030 might be pissed at me for saying that. But a lot of mappers within the community would say that off the record, that there’s just no way it’s going to happen. Take the example of Hudson Bay. It’s massive. We’ve barely mapped it. We’ve got small but important crowdsourcing projects going on. But they’re just never going to tackle that project in time. We’re probably not even going to map Hudson Bay by the end of 2030, let alone the global seafloor. It’s just very unlikely that it’s going to happen.  [Tyee]

  • Share:

Get The Tyee's Daily Catch, our free daily newsletter.

Tyee Commenting Guidelines

Comments that violate guidelines risk being deleted, and violations may result in a temporary or permanent user ban. Maintain the spirit of good conversation to stay in the discussion and be patient with moderators. Comments are reviewed regularly but not in real time.


  • Be thoughtful about how your words may affect the communities you are addressing. Language matters
  • Keep comments under 250 words
  • Challenge arguments, not commenters
  • Flag trolls and guideline violations
  • Treat all with respect and curiosity, learn from differences of opinion
  • Verify facts, debunk rumours, point out logical fallacies
  • Add context and background
  • Note typos and reporting blind spots
  • Stay on topic

Do not:

  • Use sexist, classist, racist, homophobic or transphobic language
  • Ridicule, misgender, bully, threaten, name call, troll or wish harm on others or justify violence
  • Personally attack authors, contributors or members of the general public
  • Spread misinformation or perpetuate conspiracies
  • Libel, defame or publish falsehoods
  • Attempt to guess other commenters’ real-life identities
  • Post links without providing context

Most Popular

Most Commented

Most Emailed


The Barometer

Will the BC Conservatives’ Surge Last?

Take this week's poll