China is rapidly expanding its oceanographic research efforts, but these missions are far from purely scientific. Under the guise of civilian exploration, Beijing is systematically mapping the seafloor in strategic regions across the globe, gathering intelligence that could provide a critical military advantage. With an ever-growing fleet of research vessels, China’s efforts threaten U.S. naval superiority, endanger American allies, and raise serious concerns about Beijing’s true intentions.

The Strategic Significance of Seabed Mapping

At face value, mapping the seafloor may seem like an innocuous scientific endeavor. However, detailed oceanographic data—including information on underwater terrain, salinity levels, and sound propagation—plays a crucial role in modern naval warfare. By understanding how sound moves through water, China can refine its anti-submarine warfare tactics and improve its ability to track U.S. and allied submarines. Conversely, this same intelligence can be used to make Chinese submarines harder to detect, giving them a significant stealth advantage.

The U.S. Navy and other military forces rely on submarine capabilities as a critical component of deterrence and strategic defense. If China gains superior knowledge of the ocean’s hidden topography, it could undermine America’s ability to project power in the Indo-Pacific and beyond.

China’s Global Seabed Mapping Campaign

China’s mapping activities have been met with growing alarm from governments around the world. Its research ships have been spotted conducting extensive surveys near India, Japan, Australia, and throughout the Pacific and Indian Oceans. These missions often follow a precise, lawnmower-style pattern—systematically covering vast stretches of ocean to collect high-resolution seabed data.

In early 2025, China’s Xiang Yang Hong 01 and Dong Fang Hong 3 were observed conducting extensive mapping in the eastern Indian Ocean. These vessels, along with dozens of others, operate under the control of Chinese state agencies, universities, and government-linked organizations. However, analysis shows that more than 80% of these so-called civilian research ships exhibit behavior suggesting military involvement—including visits to Chinese naval ports and operations near strategic maritime chokepoints.

Undermining U.S. and Allied Security

China’s seabed mapping directly threatens the security of U.S. allies. India, for example, has repeatedly voiced concerns over Chinese research ships operating near its Andaman and Nicobar Islands—critical military outposts that control access to the Malacca Strait, one of the world’s most vital trade routes.

In 2024, India successfully lobbied Sri Lanka to impose a moratorium on foreign research ships due to Beijing’s increasingly bold maneuvers. However, that ban expired at the end of the year, allowing China’s survey ships to resume their operations. Australian defense officials have also warned that Chinese vessels are mapping submarine transit routes near Christmas Island—an area frequently used by Australian and U.S. naval forces.

Even in the Pacific, China is making inroads. The small island nation of the Cook Islands recently signed an agreement with Beijing for oceanographic research. This partnership has drawn concern from New Zealand, which fears that detailed seabed data could be exploited for both deep-sea mining and military purposes.

A Cover for Deep-Sea Mining or Military Expansion?

While China officially claims its research efforts are driven by scientific curiosity and economic interests—such as deep-sea mineral exploration—the reality is far more troubling.

By mapping the ocean floor, China is not just identifying valuable mineral deposits but also charting potential hiding spots for submarines and optimizing routes for undersea warfare.

The Cook Islands, for instance, has some of the world’s richest deposits of deep-sea cobalt nodules—critical for producing batteries and military technologies. But to extract these resources, China needs a precise map of the ocean floor. The same maps that aid in mining also provide invaluable intelligence for submarine warfare—a dual-use capability that many Pacific nations are beginning to recognize as a national security risk.

China’s Push into the Indian Ocean and the Maldives Factor

Another alarming development is China’s expanding presence in the Indian Ocean, where it is systematically undermining India’s influence.

In early 2024, the Maldives government, under President Mohamed Muizzu, approved the docking of the Xiang Yang Hong 3—a Chinese research vessel known for conducting seabed surveys with potential military applications. The move was a significant geopolitical shift, signaling closer ties between China and the island nation, much to India’s dismay.

India had previously signed a hydrographic survey agreement with the Maldives, but Muizzu’s administration refused to renew it, effectively blocking Indian survey ships while welcoming Chinese vessels instead. This maneuver is widely seen as aiding Beijing’s efforts to map the region’s seafloor while limiting India’s ability to do the same.

The situation underscores how China is leveraging economic and political influence to gain strategic military advantages—whether through port access, research partnerships, or covert intelligence collection disguised as civilian science.

The U.S. and Allied Response: What’s Next?

Despite growing concerns, China shows no signs of slowing down its maritime intelligence-gathering operations. The United States, India, Australia, and other regional powers must take decisive steps to counter Beijing’s efforts, including:

• Enhancing naval monitoring and surveillance of Chinese research vessels operating near sensitive maritime regions.
• Strengthening alliances and security agreements to deter China’s aggressive expansion.
• Investing in deep-sea mapping technology to prevent Beijing from monopolizing undersea intelligence.
• Applying diplomatic pressure to nations cooperating with China’s mapping operations, particularly in the Pacific and Indian Oceans.

As China continues to blur the line between civilian and military research, the threat to global security grows. The U.S. and its allies must recognize China’s seabed mapping for what it truly is—an ambitious military strategy disguised as science.

Failure to act now could allow Beijing to achieve a stealth and intelligence advantage that could reshape the balance of power in the world’s oceans for decades to come.

ACZ Editor: In land-based military operations, maps are among the most valuable intelligence, whether they are yours for navigating to your own strategic positions or your enemy’s maps to determine his strategies with the idea of countering them. GPS was, in fact, constructed primarily for military purposes.

Detailed undersea charts would be a substantial advantage in submarine warfare versus submarines without them. The ability to find hiding places and other strategically superior geographic locations is a force multiplier.