The past and future surveyor

Remote control centre for USV.

(Image courtesy: Exail)

From Hydro by y Huibert-Jan Lekkerkerk

How past and current developments may impact the surveyor

The world is ever changing.
So is the profession of the hydrographic surveyor.
But how will current technological and societal changes impact hydrographic surveying? Will this be a matter of historical recurrence or are we on the brink of something completely new? Let us look at some past developments, taking a line from George Santayana (1905): “Those who cannot remember the past are condemned to repeat it.”

This article will therefore first consider some historical developments to see what may happen in the future to our profession.
Please note that this overview is neither complete nor can developments be pinned to an exact time period.

Until 1720: the age of discovery

Before the 18th century, hydrographic surveying was a very imprecise business with data unsystematically gathered from a great number of sources.
Bathymetry was mostly absent in early charts and positioning relied on relatively crude latitude measurements and dead reckoning.
Charts were either state or company secrets or were created and distributed by commercial printing houses.
Very often, information was not only inaccurate but also outdated.
New charts often copied old charts with a new look and name on them.

Hydrographic surveyors as we know them today were virtually non-existent, and chart information came from sea captains and explorers who wrote down what they witnessed.
They collected their data using whichever sailing ship they happened to be on, were often away for years on end and had to rely on navigators onboard, the education of whom was mostly in the hands of individuals.
Knowledge was transferred orally using hands-on experience or a select number of standard works on navigation that often were kept in print for decades.

Frontispiece of 'De groote lichtende ofte vyerighe colom' showing the state of the art of navigator education in the 17th century.
(Image courtesy: Allard Pierson Museum) 

1720–1920: hydrography becomes scientific

From the 18th century onwards, hydrography for the safety of navigation became more state-institutionalized, starting with the French Depot des Cartes et Plans de la Marine in 1720.
It was not until the second half of the 18th century that systematic chart updates based on proper hydrographic surveys were performed.
This was also the start of hydrography as we know it today.
First, land survey work was performed to set the geodetic network.
The development of the sextant and chronometer allowed relatively accurate determinations of latitude and longitude, which greatly improved the accuracy of data.
The hydrographic data was then systematically collected using resection from two sextant angles combined with depths from the lead and line along survey lines.
The charting itself relied, depending on the preference of the hydrographic service, on instruments such as the station pointer or on newly developed formulas.
Navigational charts were issued by governments rather than commercial companies.

Late 19th-century survey sextant.

(Image source: collection author)

As exploration became more systematic and institutional, specialized tools and training appeared.
Ships for exploration and surveys required their own outlay and specialized crew.
Engine power was adopted relatively quickly.
Hydrographic training was still ‘on the job’ and most hydrographic surveyors started their career as navigators.
Surveyors would be away for long periods but could often rely to some extent on existing infrastructure to support them.
As most surveying was government business, hydrographic surveyors became part of navies and were trained at navy institutes.
In the field they were supported by a survey crew that was trained on the job by the same surveyors who would oversee their work.
Books specifically devoted to hydrographic survey started to appear, such as those of Murdoch Mackenzie and Beautemps-Beaupre.

 

Illustration from Beautemps-Beaupre’s ‘Introduction to the practice of nautical surveying’ showing the resulting chart of a ‘modern’ survey.

(Image source: archive.org) 

1920–1970: hydrography goes electronic

The methods described were further refined during this period but essentially remained unchanged.
With the development of underwater acoustics, the single-beam echosounder made its introduction into hydrography and was quickly adopted as a standard tool.
In the United States, radio acoustic ranging was developed, a system that can be seen as a predecessor of long baseline positioning.
During WWII, electronic positioning systems were conceived which, after the war, were transformed into a multitude of high-accuracy hyperbolic and range-range positioning systems.

Photogrammetry for topography became mainstream, which also saw the introduction of aircraft into hydrography.
These new technologies were used side by side with the ‘old’ technologies.
Chart plotting did not change much and still required manual labour but chart printing was modernized.
Near the end of this period, the first of the ‘modern’ survey technologies such as multibeam echosounders, sidescan sonar, underwater acoustic positioning and sub-bottom profilers saw the light of day.

The establishment of the International Hydrographic Bureau (IHB, now IHO) in 1921 can be seen as the formal start of international cooperation which lasts until today.
With respect to hydrographic training, not much changed.
The publication of the International Hydrographic Review by the IHB and the hydrographic conferences held by the same did much to spread knowledge across the field.
Surveyors were now away for periods of a few months to maybe a year or so and could rely on existing infrastructure with relatively quick communications.

Radio acoustic ranging principle. 

(Image courtesy: NOAA) 

1970–1990: hydrography is automated

With the more systematic exploration and production of oil and gas, hydrographic surveying became a private, commercial, enterprise.
Though initially navies supported exploration, it became quickly clear that more capacity was required.
What also became clear was that project requirements were different although survey technologies were essentially the same.
Hydrographers were quick to adopt computers into the work process, allowing for faster data collection and processing.
As computer capacity increased, software became more elaborate and complete.

With the greater need for capacity, the training of surveyors could no longer be handled by just the navies, although many of the early commercial surveyors obtained their knowledge through the respective hydrographic services.
Specialized, civil training emerged with the IHO setting the standards for training programmes, which led to the Cat-A and Cat-B recognized courses we still see today.
This period also saw the establishment of hydrographic societies and new periodicals and congresses to continuously educate a much wider hydrographic audience and allow them to network and cooperate.

The surveyor from this period had to be skilled in both the ‘old’ manual techniques but also in the ‘new’ digital and electronic technologies.
The commercial environment also required faster turnaround times, and the surveyor could no longer afford a few months delay between surveying and delivering the final product.
Teams became smaller as automation did not require as many people.
The surveyor would generally be away for no longer than a few months and could rely on structured organizations and immediate communications with experts to help solve issues.

Crew at work on a survey launch in 1969.
(Image source: De Hollandse Cirkel) 

1990–2015: data revolution

GNSS and specifically dGPS were quickly embraced by the hydrographic world and almost fully replaced electronic positioning as they were about as accurate but much faster and cheaper to use.
At the same time, systems such as the multibeam echosounder and bathymetric Lidar became commercially available.
This changed the sparse data from single-beam to full bottom coverage, high-density datasets.

This period also saw the development of the geographic information system and of modern survey software to support the new data streams.
Charting became part of survey software supporting relatively quick turnaround of data to final product.
At the same time, the electronic navigational chart and electronic chart display system were defined and developed, allowing safety of navigation data to be distributed in digital form.
New platforms became more elaborate, with the ROV becoming the standard offshore tool.
The first autonomous underwater vehicles were developed but the main tool remained the survey vessel / launch and aircraft / helicopter for photogrammetry and airborne Lidar (bathymetry).

New technologies require new standards and commercial and civil institutes started to develop these standards, notably the European Petroleum Surveying Group (EPSG, now IOGP) and the International Marine Contractors Association (IMCA).
The new surveyor had to be able to handle the high data volumes and increased accuracy with tools that were still being developed and improved.
Survey crews became even smaller, but knowledge was easily disseminated through the internet and digital publications.
Hydrographic surveyors would be away for weeks to months now.
The hydrographic surveyor was responsible for a wide variety of systems using technology that was still under development.
As a result, training also became wider in subjects and more detailed in content with a focus on specific techniques and applications. 

2015–today: remote, autonomous and artificial

Most of the technologies we use today are still the same as in the previous era.
Systems have become easier to use if set up correctly.
However, clients also keep asking for more and higher quality data while setting stricter tolerances for construction.
Further miniaturization of electronics and the improvement of computing power have allowed the development of smaller and faster electronics.
Additionally, communications have become significantly faster and less expensive.

This has allowed the development of autonomous, uncrewed and remote systems.
The uncrewed aerial vehicle equipped with Lidar and photogrammetric cameras is standard on many construction projects.
The next step with remote control and remote processing of survey data with lightly or uncrewed and sometimes autonomous survey vessels is in full swing.
This has also changed the work environment; remote working does not require the remote surveyor to be away and, for the first time, some surveyors can work from behind their desk in the office and be home in time for supper.

With the increase in computing power, data processing has also become more automated.
Machine learning and artificial intelligence are out of the research phase and are slowly becoming mainstream in data processing.
Compiling data in databases and integrating it with other datasets is now standard for many clients for whom bathymetric data is just one aspect of their daily operations.

 

Cat-A students at work with a USV. 

(Image courtesy: Maritiem Instituut Willem Barentsz / NHL Stenden) 

Towards the future

What will hydrography look like in the next 10 to 20 years? No one can say for sure, but it is clear from history that new technologies will keep emerging.
Historically, hydrographic surveyors have shown themselves to be technocratic and flexible enough to be the early adopters and absorb new technologies quickly.
On the other hand, society has changed.
We can see this in the job rotation duration, which has gradually been reduced from years to weeks and for some no longer than a working day.

As the industrial revolution changed the way we propelled our survey vessels, the age of automation changes the way we collect our data.
Looking towards the future, we can see two types of surveyors emerge.
The first is very skilled in the higher theoretical and technological details of mobilization, data acquisition and processing.
This type of surveyor will possibly travel from site to site, mobilizing systems and troubleshooting them in the field.
Once the system has been set up and running, we will see another type of surveyor, more of an operator, taking over the operation.
These operators will most probably work increasingly remotely, and their main function will be overseeing the operation of highly automated systems.
When they detect an issue, they will involve a troubleshooting surveyor to analyse and resolve the issue, either through a change in the system or through corrective action with the automation.

Looking at data processing and products, we have seen a gradual change from pure safety of navigation products on paper to electronic products / data for a much wider use with integration into other datasets.
At the same time, the processing of data without major issues is becoming increasingly automated.
This will possibly create a similar division for data processing / charting as described for data acquisition.

The above translates to a potential paradigm shift in our industry that we have not seen for decades.
We will (again) require survey operators who can be trained relatively quickly and without all the theoretical details as well as more technical surveyors who can oversee the operations and can analyse and troubleshoot the system based on in-depth knowledge.
At the same time, there are so many systems around that it is impossible to be trained in detail on each system and method.
Education will need to give a basic understanding of all technologies and techniques with specialization occurring through additional formal training geared towards the application.

The above may be seen as a bad thing, but considering that it is becoming harder to obtain and retain personnel for many companies, it may also provide a way out.
The big challenge will be to sustain training programmes for the specialized surveyors if the volume drops even lower than it is today.

Raw power of the ocean

Raw power of the ocean
pic.twitter.com/B3ON0Yv0ep

— Science girl (@sciencegirl) February 24, 2026

Earth's deep tectonic “pump” moves billions of microbes to the surface in an evolutionary cycle

Cold seeps offer a brilliant window into this otherwise hidden world.

These cracks in the ocean floor act as vents, spewing enormous volumes of fluid from the subseafloor into the sea above.
Image credit: NOAA Office of Ocean Exploration and Research, 2013 ROV Shakedown and Field Trials in the U.S. Atlantic Canyons

 

From IFLS by Tom Hale

Earth's lifeless geology and its organic inhabitants share a surprisingly harmonious, cyclical relationship.
Beneath the seafloor, rich colonies of microbes thrive within buried ocean sediment.
Through the slow grind of tectonic plates, some are carried to the surface while others are swallowed into the planet's interior in what geologists have dubbed a "tectonic pump."

Until recently, scientists had little idea of just how much life lurks below the surface.
The deep subsurface was long considered too hot, too pressurized, too starved of nutrients to harbor much of anything.
But over the past few decades, advances in sampling technology and DNA sequencing have revealed a hidden “deep biosphere” of staggering scale.
By some estimates, the majority of microbes on the planet live underground, sometimes sitting dormant for thousands or even millions of years.

According to new research by the University of Southern California, the “tectonic pump” may be an important part of this process.

The researchers unearthed evidence of a giant geological “elevator” upon noticing that regions with more earthquake activity tended to harbor a greater abundance of underground-dwelling microbes on the seafloor.
Earthquakes, it seemed, were dredging these microbes up from the deep.

“We can also examine how seismic activity relates to the relative abundance of different microbial groups, and we find a positive correlation between seismic energy and the abundance of subsurface-associated microbes,” Zhengze Li, a PhD student at the University of Southern California, said in a statement.

Li and the team explain how the tectonic pump is linked to subduction zones, places where one tectonic plate slides and descends beneath another.
As the downgoing plate sinks, layers of sediment are scraped from its surface and pile up in a wedge against the overriding plate, squeezing fluid and microbial life upward in the process. 

Meanwhile, many microbes on the downgoing plate are sent on a “trip to hell,” Li said, deeper within Earth’s interior to its mantle.

For those brought back toward the surface, the journey may be a fundamental part of their evolutionary cycle, allowing them to wake from dormancy and reproduce after millions of years of dormancy.
"The full cycle – from burial and transport with the subducting plate to eventual return – can take tens of millions of years or longer," Li said.

From lava lakes to hydrothermal vents, microbial communities can survive in some of the most extreme conditions on the planet—and nowhere is that more apparent than the peculiar landscapes of the deep sea.

Dive deep with geobiologist Jeffrey Marlow to explore the hidden worlds inside a volcano and at the bottom of the oceans and discover how the incredible microbes that live there are essential to the health of our planet in ways we’re only just beginning to understand.

 
It doesn't just take a catastrophic earthquake to set the pump in motion.
The models suggest that even a “silent” slow slip event and the gradual creeping of plates can mobilize fluid and send microbes on their way.

The scale of this movement is monumental.
According to their models, the tectonic pump could circulate more than 1 million gigatons of fluid per million years, potentially transporting up to 1030 (that’s 1,000,000,000,000,000,000,000,000,000,000) microbial cells.

They may be microscopic, and it takes hundreds of thousands of years, but this would represent the largest migration of life ever recorded.

The research was recently presented at the 2026 Seismological Society of America Annual Meeting.

Strategic pings: the big silent hunters

Silent Giant - Thomas Meurling (Nano Banana and Photoshop)

From Pulse by Thomas Meurling

Extra-Large Uncrewed Underwater Vehicles, or XLUUVs, are changing undersea warfare.

Not because they are big.

Not because they are unmanned.

And not because they look impressive in defense exhibition renderings.

They matter because they can carry mission payloads into places where humans should not have to go, stay there for a long time, and collect acoustic intelligence in a GPS-denied, radio-silent, pressure-heavy environment.
But here is the uncomfortable truth.

An XLUUV without the right sonar payload is just an expensive underwater bus.

Underwater Bus

The platform provides endurance.

The payload provides purpose.

The sonar provides understanding.

Why XLUUVs Are Not Underwater Trucks, They Are Sensor Weapons

For more than a century, the submarine was the apex predator of the undersea domain.

Silent, expensive, crewed, and politically sensitive.
Now something different is entering the water.
It does not need coffee.

It does not need sleep.

It does not complain about hotel points.

It can transit quietly, sit near the seabed, map a cable route, carry payloads, listen for activity, and move again when the mission requires it.
Welcome to the age of the XLUUV.

The industry loves to talk about size, range, endurance, payload bay, and autonomy.

Fair enough.

These things matter.

Boeing describes Orca as an XLUUV with a large modular payload section intended for open-ocean transit, bottom-following, seabed operations, and mission flexibility.

NAVSEA accepted delivery of the first Orca XLUUV test asset in December 2023, emphasizing the modular payload section for sensors, communications, and mission-specific systems.

But the real question is not: how far can it go?
The real question is: what can it understand when it gets there?
Because underwater autonomy is not magic.

It is acoustics, navigation, signal processing, and mission doctrine wrapped inside a pressure hull.

In the air, a drone can use GPS, cameras, radio links, radar, and satellite communications.

Underwater, most of that disappears very quickly.

Radio frequency energy dies.

Cameras are range-limited.

GPS does not work at depth.

Communications are slow, intermittent, and acoustic.

The XLUUV relies solely on sound.
That means sonar is not a bolt-on accessory. It is the nervous system.

XLUUVs Missions

For mine warfare and seabed operations, active sonar becomes critical.

Synthetic aperture sonar, or SAS, provides high-resolution imagery over wide areas and helps solve one of the old problems of side-scan sonar: resolution degradation at range.

Traditional side-scan sonar can tell you that something interesting may be on the seabed. SAS gets you closer to understanding what it is, where it is, and whether it matters.

Multibeam echo sounders add the 3D picture.

They provide bathymetry, slopes, seabed shape, and clearance data.

That matters if you are navigating near the bottom, selecting a payload placement location, inspecting infrastructure, or avoiding an expensive collision with geology.

Passive sonar plays a different game.

It listens. It does not reveal itself by transmitting.

For ISR, anti-submarine support, pattern-of-life monitoring, and covert surveillance, passive arrays can be more important than active imaging.

The XLUUV can be equipped with a passive sonar suite; conformal array, flank array, towed array, and intercept array.

Sometimes the smartest acoustic move is to shut up and listen.

 
XLUUV Approaches

This is where the XLUUV conversation becomes interesting.

Collage of different XLUUVs (China, USA, Australia and UK)

Boeing Orca represents the heavy modular approach.

Anduril’s Dive-XL represents a fast-moving, software-heavy approach.

In March 2026, Anduril said the U.S. Navy and DIU selected it for the Combat Autonomous Maritime Platform project, aimed at advancing extra-large autonomous underwater vehicles.

XLUUVs carry payloads and provide persistence.

Medium UUVs classify and survey.

Small UUVs inspect.

USVs communicate, launch, recover, and relay.

Seabed nodes listen.

AI helps sort the acoustic mess.

Humans still define intent.

The sonar benchmark remains platforms like Kongsberg’s HUGIN Superior, even if it is not an XLUUV.

It shows what high-end undersea sensing can look like when the payload is treated as the heart of the system.

Kongsberg states that HUGIN Superior carries HISAS 1032 dual-receiver synthetic aperture sonar, generating about 1,000 meters of swath at 2.5 knots with consistent high-resolution SAS imagery, along with an EM2040 Mk II multibeam.

That is the difference between “something is down there” and “that is a mine-like object, next to a cable, on rippled sand, at this coordinate.”

Other nations are moving too.

The Royal Navy’s XV Excalibur, developed under Project Cetus, is a 12-meter, 19-ton experimental XLUUV testbed intended to explore payloads, autonomy, and future crewed-uncrewed teaming.

China’s new generation of XLUUVs suggests a serious shift in undersea power.

The focus is no longer just on small autonomous underwater vehicles for survey or inspection.

China appears to be moving toward much larger, mission-capable underwater drones designed for ISR, seabed operations, mine warfare, and potentially payload delivery.

Reports describe multiple Chinese XLUUV designs, including the AJX-002 and HSU-100, with some larger concepts reportedly exceeding the scale of the U.S. Boeing Orca.

Chinese XLUUV programs

The provocative point is that China is not betting on one platform.

It is building a family of large unmanned underwater systems with different roles, sizes, and likely mission profiles.

That gives China more flexibility than a single-purpose vehicle focused mainly on mine deployment. Compared with Western efforts such as Orca and emerging systems like Dive-XL, China’s approach looks broader, faster, and more aggressive.

The undersea competition is moving from experimental autonomy to deployable sensor-and-payload networks.

Russia continues to pursue a split path between deep-water ISR vehicles and strategic underwater weapons.

The details are often opaque, and we should be careful not to pretend that every sonar suite is publicly known. 

XLUUV Trends

But the trend is obvious.
The undersea domain is becoming more distributed, more autonomous, and more sensor-driven.
And that leads to the provocative point.

The next undersea arms race will not be won by the country with the biggest unmanned submarine.

It will be won by the country that best integrates sonar, autonomy, payloads, and mission doctrine into one coherent undersea system.

Because endurance without sensing is tourism.
Autonomy without sonar is wandering.
And a beautiful XLUUV without acoustic intelligence?
That is just an underwater bus with a defense budget.
So next time someone shows you a sleek unmanned submarine rendering, ask the uncomfortable question:
Nice hull. What sonar is on it?  (see below)

 

Links :

• THALES 76Nano sonar for XLUUV
• National Interest : Why China’s XLUUV Drones Are Sea Monsters 

Fifteen maps that changed how we see the ocean floor

 

From The Library of Lost Maps by James Cheshire

Celebrating the Pioneering Cartography of Marie Tharp and Bruce Heezen

“I had a blank canvas to fill with extraordinary possibilities, a fascinating jigsaw puzzle to piece together: mapping the world’s vast hidden seafloor.
It was a once-in-a-lifetime—a once-in-the-history-of-the-world—opportunity for anyone, but especially for a woman in the 1940s.” Marie Tharp.

A few weeks into my exploration of the University College London Geography Map Library I happened upon two drawers filled with vast “physiographic” maps.

These were not conventional contour maps, but textured, almost sculptural views of the Earth’s surface.
Many were by Armin Lobeck and Erwin Raisz, pioneers of the approach, which was especially popular in the 1940s and 1950s.

 

Physiographic Diagram of North America: The Geographical Press, Columbia University (1948) 57 × 79.5cm

Among the maps of mainland Europe and North America were three enormous ocean‑floor maps — spanning the South Atlantic, the Western Pacific, and the Indian Ocean — created by Marie Tharp and Bruce Heezen.

Tharp is now one of the most celebrated cartographers from the 20th Century (even being featured as a Google Doodle in 2022).
The maps of the ocean floor she produced with Heezen transformed our understanding of the landscape beneath the waves, simultaneously capturing the imagination of millions but also informing the theory of plate tectonics: one of the most important scientific breakthroughs of the postwar era.

When I first found these maps I recognised Tharp’s name, but I knew little about how these maps had been made.
My curiosity got the better of me, so I extended a pre-booked trip to Washington to spend several days sifting through Tharp’s vast archive housed at the Library of Congress.

Only there did I truly understand the scale and ambition of the maps of the ocean floor she dedicated her career to.

 

 

A dream come true: Viewing the “World Ocean Floor Panorama” at the Library of Congress

There so much fantastic material that has already been written about Tharp and her legacy (I’ve listed some at the end), but nowhere have I found the most signficant maps she helped to create gathered in one place.

So I have created a chronology of these ocean floor maps to show how they became some of the most well-known and influential maps of the twentieth century.
I know there are a few I’ve missed that are in National Geographic atlases and on globes, but the fifteen below show the most comprehensive evolution of the ocean floor mapping work I’ve found to date.

I’ve kept the text to the minimum here, but if you want to read my detailed version of the story it can be found in the later chapters of The Library of Lost Maps!

n.b. : Images below are largely scanned from maps held by UCL Geography/ my own collection and used here for educational purposes.
The maps remain in copyright so permission for re-use should be sought from the relevant holders.

1. Physiographic Diagram Atlantic Ocean (1957)

Physiographic Diagram Atlantic Ocean: The Geological Society of America (1957) 137.5 × 68.5cm

In September 1957 Heezen co-authored a paper in The Bell System Technical Journal titled “Oceanographic Information for Engineering Submarine Cable Systems”.
It was a specialist paper for engineers interested in laying cables, but in the back was the “Physiographic Diagram Atlanitc Ocean”, which was the first of Tharp’s major creations.

Detailed bathymetric contours were considered militarily sensitive at the time, so Tharp and Heezen took a different approach.
Instead of only charting precise depths, they focussed on the terrain and shapes of the seafloor and deflty skirted the censors.

The result was an entirely different impression of what the bottom of the ocean looked like.
Gone was the idea that it was flat and featureless: the map suggested something much more textured and intriguing.

 

Section of Physiographic Diagram Atlantic Ocean: The Geological Society of America (1957)

This map was also significant as Tharp had sketched in a rift valley along the centre of the Mid-Atlantic Ridge.
She had deduced its existence from assembling cross‑sections of depths and noticing a V‑shaped indentation in all of them that could be aligned to indicated a vast fracture splitting the ocean floor.

At first, the idea was dismissed, not least by Heezen, who like many geologists of the time, found the notion uncomfortable.
A rift implied movement.
And movement, in turn, hinted at continental drift — an idea that was still considered controversial.

But Tharp’s data became impossible to ignore, so in 1957 (the same year as the physiographic map), Tharp, Heezen, and Maurice Ewing published their findings, announcing the rift valley as a major feature of the ocean floor.
The media seized on the story.
Headlines proclaimed that the world was “cracking up.”

In the Library of Congress is a globe that Heezen has painted over to show the key geological features of the seafloor, not least his vision for a “world girdling” rift valley (in red) which dissected the oceans.

 

The combination of a map that transformed deep from a featureless plain to a dramatic series of mountains and canyons, and the finding that Earth was “cracking up” ignited the public’s imagination and caught the attention of the biggest magazines of the era.

2. The Newly Discovered World Beneath the Waves (1959)

 

 

The Newly Disvovered World Beneath the Waves: Fortune Magazine (1959)

Tharp and Heezen’s data found its way into magazines like Life and Fortune, illustrated by some of their most skilled graphic artists.
Among the first was Richard Edes Harrison, whose 1959 world map of the ocean floor brought this hidden landscape into homes and classrooms.
He used an innovative projection that helped to create this single ocean view as he explains to readers:

“The surface of the earth has been cut, like the skin of an orange, along the American continents (at longitude 70° west) and pressed flat in such a way that the relative sizes of all areas are free from distortion.”

I think this is the first global map of the ocean floor that includes the data processed by Tharp and Heezen.
It is printed on very shiny paper – in subtle colours – so was very hard to do justice in a photo!

 

 

3. The New Portrait of Our Planet (1960)

 

 

The New Portrait of Our Planet: Life (1960) 128.5 × 76cm

Kenneth Fagg’s rendering, published in 1960, is one of my favourites.
It is huge poster that splits Earth into four hemispheres set on a near black background.
Life Magazine also included it within their “Life Nature Library” books.
He chose to colour the floor by sediment type, which makes Earth look more like Mars, but Heezen felt was slightly “too bold”.

 

 

4. The Floor of the World Ocean (1961)

 

 

The Floor of the World Ocean: Association of American Geographers (1961) 68 × 40cm

In 1961 Edes Harrison produced a second map in much more muted tones to Life’s version as a supplement to an academic journal.
It was printed much larger in comparison to his original version and without the ocean currents on the top.
The thicker, uncoated, paper gives the map a much classier feel than the glossy magazine format of his first version.

5. Physiographic Diagram of the South Atlantic Ocean (1961)

 

 

Physiographic Diagram of the South Atlantic Ocean: The Geological Society of America (1962) 118 × 142cm

Buoyed by the success of their first map and the interest it generated, Tharp and Heezen pushed on into the early 1960s with their physiographic maps.
They benefitted too from a wealth of data that was being gathered on numerous expedition ships.
In 1961 they published what was to be the largest in the series: the South Atlantic Ocean…which was followed by the Indian Ocean in 1964.

6. Physiographic Diagram of the Indian Ocean (1964)

  

Physiographic Diagram of the Western Pacific Ocean: The Geological Society of America (1962) 116 × 84cm

7. Indian Ocean Floor (1967)

 

Indian Ocean Floor: National Geographic Magazine (1967) 63.2 × 48.2cm

The yellow and blue physiographic giants could be purchased for a few dollars and sent out either folded or in tubes.
These maps appealed to a fairly niche crowd of geologists and oceanographers, and certainly weren’t going to make Tharp and Heezen as well known as they are today.

It wasn’t until the late 1960s that National Geographic Magazine initiated a collaboration that would define the visual language of the ocean floor for generations.
They paired Tharp and Heezen with an Austrian artist named Heinrich Berann.
The three of them would collaborate for over a decade, with Berann taking Tharp and Heezen’s processed data and sketches to create his own renderings under their careful supervision.

The first result was a map of the Indian Ocean, published in 1967.
It amazed millions of readers with this unfamiliar perspective and shocked them with the sight of great fissures carving up the Indian Ocean.
The success of the map led to a second comission for the Atlantic Ocean in 1968.

8. Atlantic Ocean Floor (1968)

  

Atlantic Ocean Floor: National Geographic Magazine (1968) 38 × 50cm

Probably the most recognisable of the National Geographic Maps is the “Atlantic Ocean Floor”.
Whilst being visually stunning, it also shows a further breakthrough by including “transform faults”.
These are large cracks that can be seen running perpendicular to the Mid-Atlantic Ridge and are caused by the tension of the plates either side of it moving at different speeds along their length (plate tectonics was by now a widely accepted theory) .

 

Below is I photo I took (standing on a stepladder!) of the “South Atlantic Ocean” alonside the National Geographic poster to demonstrate just how large the former is – and how much Berann squeezed into the latter!

 

 

9. Western Pacific Ocean (1971)

 

The final map from Tharp and Heezen in their physiographic style is of the Western Pacific Ocean.
I love how Tharp breaks the neatline around the edge of the map to squeeze in (most of) New Zealand and Australia.

10. Pacific Ocean Floor (1969)

 Pacific Ocean Floor: National Geographic Magazine (1969) 63.2 × 48.2cm

The penultimate map published in National Geographic Magazine was of the Pacific and, finally, the Arctic followed two years later…

11. Arctic Ocean Floor (1971)

 

 Pacific Ocean Floor: National Geographic Magazine (1971) 63.2 × 48.2cm

Thanks to National Geographic and the collaboration with Berann, millions — perhaps tens of millions — of people had seen the ocean floor in a whole new light by the start of the 1970s.

12. Carte du Fond des Océans (1973)

 

Carte du Fond des Océans: Éditions Pierre Charron (1977) 96 × 54.5cm

National Geographic went ocean-by-ocean, so it had been over a decade since any illustrators had tackled a global map of the ocean floor.
Then in late 1968/early 1969 the geologist Xavier Le Pichon commissioned an illustrator named Tanguy de Rémur to create a world map (in French) based on the available maps including the physiographic maps that Heezen and Tharp had completed.
“Carte du Fond des Océans” was the result.

In the back catalogue of Heezen and Tharp’s maps the de Rémur map is often mistaken for one that they had a direct hand in.
This is understandable because it has clearly drawn inspiration from the National Geographic maps and, what’s more, a later edition was published in english under the banner of the American Geographical Society that is credited to Heezen and Tharp.
In this case their exisiting maps were used but to my knowledge they did not supply data and supervision in the way they had for the other maps

13. The Floor of the Oceans (1976)

 

  

The Floor of the Oceans: American Geographical Society (c.
1976) 96 × 54.5cm

The map above was sold by the AGS to raise much-needed funds for the society.

14. Physiographic Map of the Earth (1975)

 

Physiographic Map of Earth (1975) 76 x 50cm

Now this map by William Chesser, published in 1975 to accompany the textbook Exercises in Physical Geology by W. K. Hamblin & J. D.Howard, is the one I know least about!

I spotted no reference to it in the Tharp archive but she and Heezen are prominently credited as data sources.

It is the only map in the physiographical style of the entire globe to include land and oceans I have found and is probably not as well known.
Not least because it lacks some of the visual impact of the de Rémur map that was doing the rounds at the same time.
It would also have been eclipsed by what would be Tharp, Heezen’s and Berann’s final map…

15. World Ocean Floor Panorama (1978)

 

World Ocean Floor (1978) in this case published as a special version for the UK’s Open University.
161 x 94 cm.

In 1974, with support from the US Office of Naval Research, work began on what would become the World Ocean Floor Panorama.

This was not a compilation of previous maps, it was a painstaking re‑evaluation of the underlying data.
Heezen and Tharp returned to original soundings, refining details across every ocean basin.
In his studio near Innsbruck (Austria) Berann, joined by his assistant Heinz Vielkind, translated Tharp’s sketches into a continuous, rolling vision of the planet.

Tharp and Heezen travelled to Austria to oversee the work and by 1977 it was finished.
They were able to carefully roll the map and fly back with it to the US.

The first print tests were completed just before they headed off on a research voyage to the coast around Iceland.
It was on this trip that tragedy struck and Heezen died suddenly of a heart attack while exploring the Reykjanes Ridge in a submarine.
Tharp learned of his death by radio, while aboard another research vessel.

Upon her return, and after making arrangements for Heezen’s repatriation and funeral, Tharp continued pushing to get the map printed.
She refined the colours, oversaw the labelling, and arranged the printing.
When World Ocean Floor Panorama was finally published in May 1978, it bore a dedication from the United States Navy honouring Heezen’s contributions.

 

Photo of the World Ocean Floor Panorama manuscript

Getting to see the orignal up close (in the Library of Congress) was an extraordinary experience.
Berann and Vielkind had created a map that looked like a 3D model not a 2D painting.
It stands alone as a stunning artwork.
You can see the full size scan here.

 

 World Ocean Floor: (1977) 191.5 × 106cm

Final thoughts

 

Marie Tharp in later years surrounded by her many maps. 

Photo: Lamont-Doherty Earth Observatory and the estate of Marie Tharp.

Half a century after is was published, the “World Ocean Floor Panorama” map and others that Tharp and Heezen had a hand in still sit at the top of the Google rankings — unmatched in clarity and beauty.

 

 

A recent Google Image search for “ocean floor map”. 

The maps boxed in red come from the list above.

In an era before digital cartography, Tharp and Heezen estimated that over fifty million maps based on their work were already in circulation.
Today, that number must be vastly higher.
Billions of people have absorbed an understanding of the Earth shaped by Marie Tharp’s vision.
Further Reading

I wanted to pull together what I see are the fifteen most important maps that Tharp and Heezen were involved in to provide cartographic inspiration and broaden their canon beyond the “World Ocean Floor Panorama” which is the most frequently used to illustrate Tharp’s story.
But there is so much more to say!

So if you would like read more about how the maps were made and how they influenced the science of the time, this is what I write about in The Library of Lost Maps so do pick up a copy!

If you would like to know more about Tharp’s life and her relationship with Heezen (and others in the scientific community) I heartily recommend Hali Felt’s book: Soundings.

The Library of Congress is home to the Tharp archive and has published several articles and blog posts about it.
See here and here for two recent examples.

And if you are a cartographer looking to create your own maps in the Berann style see here.

 

Links :

• GeoGarage blog : Mapping the deep: Marie Tharp's physiographic diagram of ...  / Marie Tharp: the woman who mapped the ocean floor / Geologist Marie Tharp mapped the ocean floor and helped ... / 1968 Tharp and Heezen Map of the North Atlantic Ocean Floor / How one brilliant woman mapped the ocean floor's secrets / If the ocean was transparent : the see-through sea / The great challenge of mapping the sea / Secretly mapping the sea floor / Why the first complete map of the ocean floor is stirring ... / Secretly mapping the sea floor / Nippon Foundation wants to map entire Ocean Floor by 2030