We honor Professor Takeshi Tsuji with the Asahiko Taira International Scientific Ocean Drilling Research Prize for his pioneering achievements in utilizing core-log-seismic data to estimate pore pressure, stress, fluid flow, gas hydrate distribution and carbon sequestration potential in subseafloor oceanic crust and subduction settings. By integrating International Ocean Discovery Program (IODP) and seismic data, Professor Tsuji's research has resulted in significant advances in our understanding of the geological processes that drive earthquakes and other natural hazards, improving our understanding of the mechanisms behind different types of earthquakes. His work has shed new light on pore pressure and the stress state in the Nankai Trough accretionary prism and plate interface. He has proposed new interpretations for the Nankai plate boundary fault, characterizing areas of slow and fast earthquakes, identifying geological structures that control large (fast) earthquakes along the plate interface, and finding that slow earthquakes are dominant in areas with high pore pressure.

Notably, Professor Tsuji has also devised innovative molecular-scale and pore-scale numerical simulations to investigate fluid circulation systems and chemical reactions in geological formations. He has made important contributions to the development of the concept of digital rock physics, a groundbreaking approach that uses high-resolution computerized tomography (CT) images to digitize discrete rock samples and investigate fluid behavior, mineralization processes and elastic wave velocity propagation inside the digitalized rock using a high-performance computer. Professor Tsuji is a global leader in this field and has been simulating fluid flow using digital rock models with exceptionally detailed grids. These methods are expected to lead to the construction of advanced rock physics models that link fluid behavior and elastic properties to quantify seismic faults.

Professor Tsuji has applied these integrative methods to quantify the methane hydrate and free gas saturation in the Nankai Trough with high spatial resolution and to identify large gas reservoirs close to the spreading axis of the Okinawa Trough. He has also been a leader in applying these approaches to understanding the carbon sequestration potential of the oceanic crust.

Professor Tsuji has been an active ambassador for scientific ocean drilling by presenting his research widely in high-impact publications and at international conferences in geosciences and geoengineering. He has also made important contributions to IODP through his service as a shipboard scientist and co-chief scientist and on international and national committees. In sum, Professor Takeshi Tsuji truly epitomizes the spirit of the Taira Prize!

— Keir Becker
University of Miami
Miami, Florida

I am deeply honored to receive the prestigious Taira Prize. I would like to express my heartfelt gratitude to Keir Becker for his kind citation.I first joined an ocean drilling cruise, IODP Expedition 301, when I was a student. I was excited because many specialists were on board for the cruise. This experience amplified my ability to integrate diverse methodologies to address scientific objectives, such as understanding fluid flow in oceanic crust. Indeed, it was during this drilling cruise that I decided to study rock physics, which has since become one of the central pillars of my ongoing research. The 2-month research cruise, guided by distinguished researchers, including Andrew Fisher, Tetsuro Urabe, Adam Klaus, Gerardo Iturrino, Fumio Inagaki and many others, was an invaluable opportunity for me. I also participated in IODP Expeditions 327 and 358, and I gained valuable experience that I could not get elsewhere. I believe that the international cruise environment fosters cross-cultural perspectives and nurtures the growth of researchers. Thanks to these experiences, my current research topics span a wide range, including space exploration.I am particularly interested in estimating pore pressure and its spatiotemporal fluctuations. This study has opened up exciting possibilities for monitoring pore pressure and stress states within volcanoes and plate convergent margins, potentially aiding in disaster estimation. This monitoring technology is also crucial in engineering projects for carbon neutrality, such as carbon capture and storage. Advances in sensing technology and computational capabilities have empowered us to unravel the dynamic behaviors of our Earth. I have especially used seismic approaches to image and monitor Earth. Due to recent advances in sensing technology, vibration information, which was previously not widely utilized by humans, now has many practical applications.I am delighted to collaborate with the members of our lab. Engaging in discussions with such intelligent researchers and students truly stimulates my brain. Additionally, Kyoko Tonegawa kindly supports me in the administrative work of our lab, allowing me to dedicate more time to research. Finally, I extend my deepest gratitude to my parents and family. In my childhood, I struggled with reading Japanese characters, particularly Hiragana and Katakana. Despite these challenges, my parents provided support and education. Today, I am able to read long sentences and can participate in research cruises. Furthermore, my wife and children help me relax, and our time together enables me to engage in scientific inquiry with profound depth.— Takeshi Tsuji, The University of Tokyo, Tokyo, Japan