Subsea Fiber Optic Cables: If There Is a Cable, There’s Data
How a scientist building the world’s most precise clock found a way to measure earthquakes, and how an internet cable became a seafloor sensor array. EGS Case Study No. 2.
This is the ExAI blog edition of EGS Case Study No. 2. It adds a Value Generation section to the initial version posted on EGS Substack and my LinkedIn
This is EGS Case Study No. 2, the Subsea Fiber Optic Cables case from my dissertation. It is a technical, impactful, and widely interesting case describing how the exaptation occurred, how it generated value for multiple stakeholders in distant domains, and what practitioners can learn from it to develop their exaptation-based growth strategy. The case details the specific activities, experiments, and insights developed by Marra’s research team over several years to intentionally develop the novel functions.
Exaptation is when an existing asset or resource takes on a function it was never designed for. This case demonstrates the expansion of the subsea cables from internet connectivity to becoming an environmental sensor array for multiple, novel functions. As in the Google Search case, the people who found the new function did not own the resource. Unlike Google’s founders, they were scientists, and most of the value they created went to others.
The pertinent exaptation question from this case is now a prompt type for EGS: Where there is X, there is also Y which can be exapted.
Case Context: What Do You Do When There Is an Anomaly in the Data You Cannot Explain?
In 2016, Giuseppe Marra, a research metrologist, a scientist who specializes in measurement, at the National Physical Laboratory in Teddington, UK, was studying time as part of a project to build the world’s most precise clock. He noticed a slight discrepancy in the experiment’s data set that tracked ultra-stable lasers fired through underground fiber optic cables. When fired, the lasers should have arrived at a certain point at a specific time but arrived later than expected. As he investigated the cause of this delay, Marra stumbled upon an unlikely reason beyond his field of study. At the same time as the lasers were firing, there was an earthquake a thousand miles away in Italy, and the energy waves created by the seismic event shook the fiber optic cables, thus producing a noticeable delay or a wiggle in the oscillation of the laser wave.
Marra learned of the earthquake on the news but did not appreciate its impact until the next day in his lab when he noticed that the time of the earthquake and the wiggle synced up. The British Geological Survey data helped him calculate that the earthquake shifted the cable by a millimeter and created the delay. A scientist attempting to create a precise clock at the scale of a quintillionth of a second had instead observed the power of an earthquake at the scale of a millimeter. A minuscule noise in the data, which is often neglected, turned out to be a signal of something meaningful: a way to measure earthquakes.
Earthquakes are one of nature’s most destructive events. They can be notably worse if they occur under the ocean, where they can create tsunamis that devastate coastal communities and economic infrastructure, such as the Fukushima Nuclear Power Plant in Japan. The 2011 Tohoku earthquake and tsunami caused an estimated ¥16.9 trillion (about $211 billion) in direct damage, the costliest natural disaster on record at the time. Scientists study earthquakes to improve our understanding of their power and find ways to monitor and eventually predict them with as much warning as possible. Doing so underwater is doubly difficult because there is a lack of ocean sensors relative to land-based seismometers, and existing methods to provide coverage through ships, naval vessels, sensors, satellites, and buoys are insufficient.
Scientists have known about this problem for decades and have tried to use existing subsea fiber optic communication cables to generate insights. By deploying techniques such as Distributed Acoustic Sensing (DAS), which is based on using lasers to study sound waves, or Interferometric Sensing, which is the study of any wave, prior research teams have been able to obtain data for such events as earthquakes and volcanoes. However, these techniques were limited to measuring movement near the beginning and end of the cable, or across the whole cable at once, and not at smaller intervals between the long cable lines. That causes the data to be less valuable since the earthquake and its after-effects are detected at intervals of thousands of kilometers, ultimately limiting precision.
Advantageously, there was a new opportunity to leverage the abundant resource already operating in the world’s oceans. Fiber optic cable networks span the globe, connecting distant places via the internet. This submarine communication system comprises about 570 cable systems covering nearly 1.4 million kilometers and transmits 99% of global digital information across continents. Telecom companies, internet service providers, and technology companies like Google and Meta own these resources to enable internet communications, thus fulfilling dual roles as a profit-making venture and essential public infrastructure. However, previous techniques were limited in how much data could be generated, and the full affordance of the resource, meaning everything it makes possible, was not actualized until Marra and his team began to tackle the issue in 2016.
Case Process: What Did Marra and the Team Do?
After the initial discovery in the lab, Marra began a new project to detect and monitor earthquakes. His team took a different approach by relying on a different part of the cable network. The more recently laid fiber optic cable lines have a piece of equipment called a repeater every 45 to 90 kilometers. The repeater amplifies the incoming light wave and sends it forward to the next section of the line so that the signal remains strong. For example, the cable line between Halifax, Canada, and Southport, UK, is about 3,600 miles long and has 128 repeaters, about 46 kilometers apart on average.
The team used repeaters along this line to take three different types of measurements to determine the earthquake’s existence, cause, and location.
First, instead of firing lasers and looking at the delay or scattering of the light wave, which is the norm in interferometric sensing, the team sent a light signal down the line and looked at the frequency of the light that reaches a repeater. The frequency of a light wave refers to the number of waves that pass a fixed point in a specific period, like one second. If the light reaches the repeater intact with the same frequency, there is no disturbance, and the signal is stable. However, if there is a change in frequency, some disturbance, such as an earthquake, tides, or something else, is causing it.
Second, the change in frequency can provide a tell-tale signal of the cause of the disturbance due to specific patterns. The frequency of a tsunami-related disturbance would differ from earthquakes and tides. Once scientists identify the different types of disturbances resulting from an earthquake, a tsunami, a surface tide, a subsurface wave, and so on, they can use the new knowledge again anywhere in the world.
Third, the team used a different part of the equipment to determine the precise location of the disturbance by using the speed of light waves, which were being slowed down due to geological phenomena. Researchers innovatively used the existing tiny mirrors in each repeater to monitor the phase shifts across each section of the cable line and detect precisely where changes occurred.
Whereas the previous techniques measured the cable only near its ends or as a whole, this new technique could turn each section between two repeaters into its own sensor, up to 128 along this one line, thus transforming a single long cable line into a sensor array that can monitor disturbances in the marine environment. According to Marra, the team transferred the lab’s ultra-stable optical frequency metrology techniques to the marine environment to enhance scientific knowledge about Earth’s systems.
The team had to do significant work to convince the operator of the cable, Google, to use their equipment. After initial reservations relating to maintaining the quality of the cable and the resulting delay, Google allowed the team to use a section of the cable. The team could use the cable so long as there was no effect on the primary function of the resource: internet communication.
In 2021, Marra’s team successfully experimented with the new technique and found two tremors. In subsequent trials, they found disturbances with a different signature, which turned out to be surface-level ocean waves driven by a cyclone. The first trials used up to 12 sensors along the cable. As the process develops, the same line can serve as up to 128 distinct sensors, ultimately creating a sensor array. Specifically for earthquake monitoring, they could be classified as 128 localized earthquake detectors.
Case Results: The Physical Cables Are the Same
This breakthrough, the ability to detect ocean disturbances with fiber optic cables, was six years in the making, and its impacts show no sign of stopping. The new technique can help monitor the ocean floor with thousands of permanent real-time environment sensors, effectively creating a new resource with multiple new functions. The physical cables are the same, but their expanded functionality transformed them into a different artifact. In addition to sensing earthquakes, the new scientific method and the existing and new resources can also detect tsunamis, monitor ocean waves and currents, help improve climate research, record seismic phases for imaging suboceanic structures, study the sensitivity of the fiber optic cables to temperatures, currents, and other phenomena, and study the earth’s interior. In this case, the existing, in-use fiber optic cable line has been exapted from its original communication function in the telecommunication industry to many other functions relating to earth monitoring in the scientific domain. This transformation was only possible with the initial curiosity of the scientists and the active participation of many different stakeholders.
The subsea fiber optic cable network is expensive to design, construct, and operate. The sole business reason for the cables to exist is data connectivity. The resource owner did not intend to add any equipment or provide access to it while it was used for the primary function. Also, the industry consortia, who have a global view of this resource, were not enthusiastic about adding a scientific function due to concerns about the legal protection afforded to the fiber optic cables by the UN Convention on the Law of the Sea. According to an industry CEO, they preferred governments to mandate collaboration between companies and researchers, thus reducing individual risk and leveling the playing field for all cable operators.
Beyond this team’s collaboration with Google, another team was able to form partnerships with new agents, the Government of Portugal, to introduce these scientific experiments into the design and construction of new fiber optic cables. The new system, Atlantic CAM, links mainland Portugal with the Azores and Madeira and is scheduled to go live in 2026. Since Marra’s work demonstrated that scientific investigations can be conducted without modifying or interrupting the original resource, there is renewed interest in using these existing resources for experiments, which may yield more new functions.
Given the magnitude and ferocity of the underlying destructive events, even a tiny improvement in detecting, monitoring, and warning systems could substantively impact economic and personal outcomes. Coastal communities and the insurance companies that serve them can avoid massive losses. Coastal infrastructure like shipping ports, power plants, tourist destinations, and so on can develop proper business continuity plans with advanced notice. While a numerical analysis of financial impacts is complex, the customer base is highly motivated to pay for this information. Each stakeholder can leverage the newfound functionality as a direct result of these exaptations.
Without the scientific and technological breakthrough, it would not have been possible to convince stakeholders to cooperate for a scientific function they had little interest in. The ability to use compact, low-cost, and commercially available lasers makes the new technique highly scalable, with the potential to turn the existing subsea cable infrastructure into “a global network of environmental sensors.” As new agents interact with this resource, additional functions may emerge.
Value Generation Across the Five Emergent Functions
Exaptation is not the goal. Value is. In EGS, value generation runs through five stages: value discovery from exaptations, value creation for customers, value delivery to customers, value capture for the firm, and value sharing with stakeholders. The table follows each of the cable’s five emergent functions through all five stages. The dot in the Created column shows which functions were demonstrated in the trials and which remain a stated potential.
| Emergent function | Discovered | Created | Delivered | Captured | Shared |
|---|---|---|---|---|---|
| Earthquake sensing | DiscoveredA data anomaly in Marra’s 2016 clock experiment, when an earthquake in Italy shifted a cable by a millimeter. | CreatedDemonstrated. Two distant earthquakes detected on single spans in the 2021 trials. | DeliveredReal-time detection on spans about 46 km apart, with no change to the cable or its internet traffic. | CapturedPublished results and recognition for the researchers, goodwill for the cable owner. No monetary capture. | SharedSeismologists, governments, and coastal communities, where the ocean floor had few sensors. |
| Seismic imaging | DiscoveredThe same technique records seismic phases on each span. | CreatedStated potential: imaging suboceanic structures and the earth’s interior. | DeliveredPublished data and methods that other scientists can reuse. | CapturedScientific knowledge. No monetary capture. | SharedOceanographers and geoscientists charting Earth’s interior. |
| Cable sensitivity | DiscoveredSpans respond to temperatures, currents, and other phenomena. | CreatedStated potential: how the cables themselves respond to their surroundings. | DeliveredResearch findings on the cables’ own behavior. | CapturedScientific knowledge. Possible value to cable operators.* | SharedScientists and, potentially, cable operators.* |
| Tsunami warnings | DiscoveredA tsunami-related disturbance would carry a different frequency signature from earthquakes and tides. | CreatedStated potential: the next application, not yet demonstrated. | DeliveredBeing built into new SMART cable designs, starting with Portugal’s Atlantic CAM, scheduled for 2026. | CapturedExpected to land with others, such as insurers, ports, and governments, more than with the finders. | SharedCoastal communities, insurers, and coastal infrastructure that gain time for business continuity plans. |
| Monitoring currents | DiscoveredIn later trials, a different signature turned out to be surface-level ocean waves driven by a cyclone. | CreatedDemonstrated. Ocean waves and currents detected on single spans. | DeliveredReal-time information about ocean tides, waves, and currents. | CapturedScientific knowledge. No monetary capture. | SharedMarine operations and climate scientists modeling deep water flows. |
| Across all five | DiscoveredOne discovery, made by new agents from another domain. | CreatedTwo functions demonstrated and three stated potential, all on an unchanged resource. | DeliveredMostly by other agents, over time. | CapturedNo monetary capture for the finders or the cable owner. | SharedFar more value shared than captured. |
There is significantly more value sharing than value capture in this case of science-related exaptation. Product-Market Fit was achieved when the new experiments demonstrated successful detection and monitoring capabilities that served the needs of multiple new customers.
The table shows that this held for two of the five functions, earthquake sensing and monitoring currents, so practitioners should count emergent functions by the evidence behind each one. The scientists were not motivated in generating revenue or delivering the end-results to new agents. Other agents have to get involved in value delivery to the end-users over time. Here those agents are governments and cable builders.
Portugal’s Atlantic CAM, a €154 million system supported by €50 million from the European Union, builds sensing into a new cable from the start. For asset owners, that is the signal worth noticing: a second function found in today’s asset can shape the design and budget of the next one. Value capture will be both monetary and non-monetary, which is peculiar in this case. Agents’ motivations matter!
The Case at a Glance
The EGS case table breaks the case down across each element of the EGS model. Instead of a table, here it is laid along the cable itself.
What the Case Demonstrates
1. New Agents Present: The new function was found by a distant agent. A new agent, who was distant and not involved in the resource’s existing function, was able to find a new function while working in their domain. The eureka moment was based on a data anomaly and their curiosity.
2. Latent Properties: The cables had properties their designed function did not use. These tangible assets were owned by other firms and not available for other uses. Thus, they were inaccessible to the new external agents, thus limiting their affordance. In addition to affordance, the designed function did not use the full suite of resource properties.
3. Expansion, not shift, of Functions: The cables kept their first job while taking on new ones. The original internet connectivity function was not lost as cables began serving new functions. Thus, this is a case of expansion of functions, where new resource functions were added. The physical infrastructure didn’t change, but its functional utility expanded.
4. Multiple Exaptations: One discovery led to several new functions. Their initial goal was to detect and monitor underwater earthquakes, but multiple new functions emerged. There are as many as five exaptive functions: earthquake sensing, seismic imaging, measuring cable sensitivity, tsunami warnings, and monitoring currents.
5. Multiple VDMs: Several discovery mechanisms worked together. There are multiple value discovery mechanisms (VDM) at play in this case, similar to other cases: new science and technological advancements, a data anomaly in the lab, an edge case of the cables, experimentation, involvement of new agents from another domain, and specific resource properties. These VDM act at various levels of the EGS model to help find latent functionalities of the asset or resource.
6. Distant Industry Sectors: The application domains moved far from telecommunication. The application domains expanded from telecommunication to infrastructure protection, insurance, business continuity, disaster avoidance, and related domains. The presence of new agents and functions enables the extension of novel solutions in vastly different economic sectors.
7. Global Shared Value (k<1): Value sharing far exceeded value capture. The research team published exciting new results, and resource owners generated goodwill. There was no monetary value capture for these primary agents. The value will be captured by other agents throughout the world and society, and it will be both monetary and non-monetary. Agents’ motivations matter!
Where There Is X, There Is Also Y
Instead of a valuable resource sitting plainly or eventually becoming obsolete, this new technical advancement increased the optionality of the resource and generated new value for the world. The subsea cables were built to carry internet traffic, and they still do. The same cables, light, and repeaters were also carrying a second signal that no one had a reason to read until a scientist building a clock noticed a wiggle in his data.
For an organization, the question from this case is easy to ask: where there is X in our business, what Y is also there? The X might be a fleet, a network, a data set, or a factory floor.
The case also raises a question for asset owners. The cable owners gained goodwill, while most of the financial value from these new functions will be captured by others. When an outside agent finds a second function in an asset, who captures the value?
At Exaptation AI, we are building the search engine for every asset’s undiscovered functions. Growth is a search problem, and sometimes the search starts with a wiggle in the data.
Earlier in this series: Google Search: A $1 Trillion Exaptation (EGS Case Study No. 4).
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