Dimensional analysis unexpectedly indicates the world’s first petroleum discovery at depths exceeding 10 km

For ages, scholars and engineers across the globe have been unceasing in their quest to unlock the mysteries of the 10,000-m-deep Earth, driven by the pursuit of new scientific theories and energy resources. On February 20, 2025, China National Petroleum Corporation (CNPC) made a momentous announcement: China’s inaugural scientific exploration well at the 10,000-m level, the “Shenditake 1” well, nestled in the hinterland of the Taklimakan Desert in Xinjiang, was officially completed after reaching a staggering depth of 10,910 m beneath the surface. Within the depth interval from 10,851 to 10,910 m, they unearthed high-quality ancient source rocks and clear indications of petroleum.1 This marked the world’s first instance of detecting and validating the presence of petroleum at a depth exceeding 10,000 m on land. As a result, it has significantly overturned the scientific community’s long-held beliefs about the depth at which petroleum can exist, thereby laying a firm cornerstone for China’s stride toward "energy independence." Intriguingly, this groundbreaking discovery aligns remarkably with the prediction put forward by the research team from the Institute of Mechanics, Chinese Academy of Sciences, based on dimensional analysis, presenting a remarkable congruence between theory and reality. This study aims to interpret CNPC’s engineering achievements from the perspective of theoretical researchers.

Kerogen, often referred to as the "parent substance" of petroleum, has the potential to yield hydrocarbons over an extended period under appropriate temperature and pressure conditions. Nevertheless, the highly intricate molecular structure of kerogen and the complex physicochemical environment within the Earth render the potential for petroleum generation subject to a multitude of factors. Scientists have long been dedicated to defining the depth limit at which kerogen can effectively generate petroleum. This would enable the precise demarcation of exploration areas, thereby substantially conserving time, manpower, and material resources.2,3 However, for a long time, there has been a dearth of an estimation equation that is both physically meaningful and concise in form to address these concerns.

The drilling of the Shenditake 1 well was independently completed by the CNPC team. The authors’ team has long focused on theoretical research in deep-Earth hydrocarbon generation, having proposed the ultra-deep hydrocarbon generation depth hypothesis via dimensional analysis.1,4 The discovery of petroleum at 10,851–10,910 m underground marks the first validation of the hypothesis’s feasibility, demonstrating that basic research and engineering practice are two sides of the same coin, each indispensable to the other. Even though they are likely to be carried out independently by separate research teams, their symbiotic relationship is the cornerstone of scientific and technological progress. Looking back to 2023, the authors’ research team posited that the petroleum generation process involves the transformation of initial kerogen, which features a complex structure, a large molecular molar mass, and a low dissociation energy for hydrocarbon generation. This kerogen gradually evolves toward a simpler structure, with a decreasing molecular molar mass and an increasing dissociation energy for hydrocarbon generation. Consequently, the real-time dissociation energy for hydrocarbon generation and the real-time molecular molar mass of kerogen are the most immediate internal determinants of the real-time petroleum generation potential.4 Additionally, temperature, stress, and terrestrial heat flow are crucial external factors. By comprehensively weighing these internal and external factors influencing kerogen-derived petroleum generation, they employed the fast-matching method of dimensional analysis to derive, for the first time, an estimation equation for the lower-limit depth of petroleum generation from kerogen. The equation reveals that the lower-limit depth is primarily contingent upon the ratio of the dissociation energy to the molar mass at the conclusion of hydrocarbon generation (the higher this ratio, the deeper the lower limit). They also crafted the first distribution histogram of the predicted lower-limit depths of petroleum generation from global kerogen, suggesting that the likelihood of discovering petroleum below 10,000 m is high, with a maximum lower-limit depth of approximately 16,337 m (Figure 1). At that juncture, this theory was merely at the academic hypothesis stage, aiming to extend the theoretical boundaries of petroleum exploration depth. Yet, unexpectedly, just 2 years later, the discovery of high-quality source rocks and petroleum manifestations by the Chinese within the depth range of 10,850–10,910 m precisely fell within the predicted range of the lower-limit depth of hydrocarbon generation from the aforesaid kerogen. This incontrovertibly demonstrates that at this depth, kerogen still retains the energy and material requisites for petroleum generation. It also fully validates the feasibility of petroleum resource exploration in ultra-deep regions and the necessity of developing ultra-deep drilling engineering technology at the 10,000-m level, further underscoring the prescience and immense value of basic theoretical research.