VALENTINA BARANOVA
SEQUENCE STRATIGRAPHER
VALYA@PETROEXPLORERS.COM

AZER MUSTAQEEM
RESERVOIR GEOSCIENTIST
AZER@PETROEXPLORERS.COM

The 8th International Workshop on Rock Physics was held in Auckland, New Zealand on February 22-27, 2026. The workshop was organized by the International Association of Rock Physicists (IARP). The program covered various topics related to rock physics, such as digital rock physics, modeling and simulation, geofluid systems, the physics of fractured rocks, the impact of fluids on the rock matrix, rock physics and volcanology, faults and earthquakes, and even planetary rock physics. The program encompassed theoretical, numerical, and experimental advances, mainly gravitating towards digital rock physics and innovative laboratory methods. The necessity to add another rock physics workshop to the already existing rock physics symposia organized by the SEG and EAGE was to address the gap in laboratory rock physics research. Initially, the workshop started as the International Workshop on Seismic Anisotropy in 1984 and was held every two years. Later it became the Rock Physics Workshop. The first one was held in 2011 at the Colorado School of Mines, followed by events in Southampton, UK (2013), Perth, Australia (2015), Trondheim, Norway (2017), Hong Kong, China (2019), A Coruña, Spain (2022), and Pau, France (2024). At the end of each workshop participants must vote for the location of the next one to be held, preferably on a different continent.

This event was hosted by the University of Auckland at its world-famous Rock Acoustic Laboratory. The laboratory is led by Dr. Kasper van Wijk and Dr. Ludmila Adam. It has a 25-year history in the study of fundamental problems in wave propagation and applied research. The applied research mostly focuses on experimental rock physics for the understanding of geohazard. This type of research is high priority for New Zealand which is considered as one of the most tectonically active countries globally. It records approximately 20,000 earthquakes annually with about 150 to 200 quakes that are large enough to be felt. Its North Island is situated right on a highly active plate boundary of the Australian Plate and the South Island is located on the Pacific Plate which is moving toward the Australian Plate at high speed. (GeoNet, New Zealand). Recently, laboratory research is supporting carbon sequestration programs as well as planetary geophysics. The Physical Acoustic Lab works, as well, on non-destructive testing of fruit, ice, and timber, as well as laser ultrasonic and photoacoustic medical imaging.

Figure 1: 8IWRP participants before group dinner at the Waiheke Island local winery.

There were more than eighty workshop participants and seven invited speakers. Invited speakers started every session with a talk which set the tone of the session. The presenters ranged from working in academia to working in private companies. Every session was followed by an intense discussion of recent advances and poster presentations.

Dr. Tapan Mukerji (Stanford University), who opened the session on Digital Rock Physics, Modelling and Simulation, spoke about the success of the application of deep learning in direct numerical calculations of physical properties (elastic moduli, permeability, electrical conductivity, etc.) over large 3D digital rock volumes. In his talk, Ronny Hofmann from Shell Exploration showed that various approaches have been developed to assess the influence of lithology on seismic attributes and to differentiate between brine- and hydrocarbon-saturated pore spaces using fluid substitution. Yury Alkhimenkov from the University of Lausanne, Switzerland talked about a 3D GPU-accelerated solver for the effective elastic properties of heterogeneous digital rocks reconstructed from micro-computed tomography (microCT) images. He showed that developed, combined methodology provides a reproducible and computationally efficient path for linking microstructure to pressure-dependent elastic properties. Anna-Maria Eckel from the GFZ Helmholtz Centre for Geosciences in Potsdam, Germany showed that hydrogen injection into the Stuttgart Formation at Ketzin is unlikely to trigger fault reactivation, and that the reservoir remains mechanically stable. Her future work will include simulation to include full slip displacement analysis and stress distribution in the caprock. Researchers from Ruhr University Bochum in Germany, Nils Kerkmann and Mirko Siegert, showed the application of digital rock physics to drill cuttings to estimate frequency-dependent properties in exploration drilling for geothermal reservoirs. They are confident that they will be able to make meaningful predictions about the rock surrounding the borehole using drill cuttings. Furthermore, the combination of drill cuttings and digital rock physics would represent a considerable increase in efficiency, saving time and reducing costs in exploration drilling for geothermal reservoirs.

Keynote speaker for the session on Geofluid Systems: Fluid Migration through Rocks, Steve Morice from Todd Energy and Seis Momentum Ltd. of New Zealand, talked about the role of rock and fluid physics in petroleum exploration and production in New Zealand and the likelihood of a proposed CCS project in the Kapuni field. He started with an overview of rock and fluid physics applications in the petroleum industry in New Zealand followed by the study investigating the geophysical properties of fluids for monitoring a proposed CCS project at the Kapuni field, onshore in the Taranaki Basin of New Zealand.

This session also included a talk by the Bedretto Team from ETH Zurich about establishing a 100-meter scale reservoir test bed in the Bedretto Underground Laboratory in Switzerland to enable in-situ experiments. It is equipped with a high-resolution multi-parameter monitoring system to conduct a series of hydraulic stimulations to better understand reservoir creation induced seismicity.

Talks also included investigation done by the team led by Boris Gurevich from the Centre for Exploration Geophysics at Curtin University, Australia, of spatio-temporal variations in strain and temperature recorded by distributed temperature sensing (DTS) and distributed strain sensing (DSS) during CO2 injection into a deep saline aquifer. The team from the Institute of Earth Sciences, Lausanne, Switzerland, talked about the anisotropic dynamic response of isotropic fluid saturated rocks and how their findings provide clear numerical evidence of dynamic, wave-induced anisotropy resulting from fluid-solid coupling in isotropic porous media. Maureen James from the Colorado School of Mines showed the importance of the integrity of seals at CO2 sequestration sites. Her results emphasize the importance of including diffusion and sorption effects in CO2 storage risk assessments and conformance models. Tapan Mukerji and Yashee Mathur from Stanford University, USA, talked about the effectiveness of geophysical methods of exploration to delineate hydrogen. It was pointed out that the next decade will show whether hydrogen is merely a geological reality worthy of our attention, a valuable energy source or a complete game changer. Ludmila Adam of the University of Auckland, New Zealand, showed the potential for large scale storage of hydrogen in depleted gas reservoirs within the Taranaki Basin in terms of understanding of hydrogen-brine rock interaction.

Dr. Manika Prasad, keynote speaker for the session Broken but Functional: the Physics of Fractured Rocks, emphasized that the quantitative mapping of CO2 is only possible with rock physics guided geophysical monitoring that reliably quantifies and verifies the fate of the injected CO2.Other talks in this session included a study by Guadalupe Flores and her team from the University of Lausanne, Switzerland, of the frequency-dependent behavior of attenuation and dispersion measured in fluid-saturated sandstone caused by squirt flow. Yevhen Kovalyshen and co-authors from CSIRO Energy, Australia, talked about applying machine learning for ultrasonic monitoring of fluid-induced shear fault reactivation. The team from Indonesia, Pertamina Energy and University Gadjah Mada, showed the importance of rock physics modeling in the prediction of hydrocarbon bearing facies in areas with rapid depositional changes and mineralogical variability. Jarrod Dune and James Parsons from QIntegral Pty Ltd, Australia, presented a longitudinal study of explorational rock physics trends. Comparisons between different basins such as the Campos Basin, Gulf of Mexico, and Australian basins, using common seismic AVO inversion attributes and assuming full seismic resolution of each lithofacies, reveal the role of geological drivers such as provenance, sedimentation rate, temperature and uplift.

Dr. Tongchen Han, of China University of Petroleum, keynote speaker for the session Experimental Frontiers and Low-carbon Geoenergy Science, showed that the key to successful joint seismic and electrical interpretation relies on understanding the correlation between elastic and electrical properties of the reservoir rocks with temperature being shown to affect both the elastic and electrical properties of the rocks. Maxim Lebedev from Curtin University, Australia, emphasized the clear need for a simple and rapid laboratory system capable of measuring Young and shear moduli under elevated pressures and potentially high temperatures. The combined team from CSIRO, Australia, and Shell, the Netherlands, showed the importance of monitoring mechanical and transport properties of reservoir rocks during cyclic hydrogen injection and withdrawal in underground hydrogen storage. Another joint research team from the Marine Geoscience Centre (UK), the British Geological Survey and the University of Sao Paulo, Brazil, showed the experimental work that is needed to validate the models and improve the interpretation of the phenomena occurring underground during geo-storage operations. Prescelli Annan from ETH Zurich, Switzerland and her team talked about the challenges and problems arising from CO2 storage in basaltic formations.

Dr. Elisabeth Bemer, IFP Energies Nouvelles, France, keynote speaker for the session Impacts of Fluids on the Rock Matrix, talked about the effect of alteration processes on the acoustic signature of carbonate rocks during carbon storage. She pointed out the lack of appropriate laws to describe the evolution of the hydromechanical properties of different rock formations under the effect of chemical alterations. A team led by Umar Fauzi from the Institute Teknologi Bandung of Indonesia, demonstrated the understanding of the mechanism of changes in elastic properties which may help develop treatment strategies to enhance hydrocarbon recovery. A multinational team of researchers from different universities, led by Dr. Kerry Leith from New Zealand, talked about recent experimental and modelling advances that demonstrate how absorption stress and mechanical loading jointly control elastic behavior in crystalline and clastic rocks. Mark Totani from the Colorado School of Mines, presented his study of seismic signatures during geochemical interactions between rock forming minerals and brine with CO2. Joint research between the Technical University of Denmark and Aker BP of Norway, presented by Shohreh Iraji, showed that North Sea unconventional reservoirs containing siliceous mudstones with high internal surface areas and a substantial amount of moisture which may be absorbed at the mineral interface can compromise porosity estimates. Jonathan Simpson of MIT talked about an experimental study of flow-through experiments on thermally cracked basalt and peridotite in which permeability, porosity, ultrasonic velocity and outlet fluid chemistry were tracked during carbonate precipitation from reactive fluids. Fourier Latief of Institut Teknologi Bandung, Indonesia and his team investigated how acidizing treatments can change the internal pore structure and fluid flow in carbonate rock samples to optimize well treatment and enhance hydrocarbon production.

Keynote speaker for the session Frontiers in Rock Physics: Planetary, Non-linearity, Geomech/Geophy Coupling, Yves M. Leroy of Imperial College of London, UK, talked about a new numerical platform developed by his multinational team, for laboratory rock mechanics based on the finite-element method to support experimental rock mechanics in two ways: precisely pinpointing ultrasonic S-wave arrival times and physically explaining hysteresis during cyclic, hydrostatic loading. Boris Gurevich of Curtin University, Australia, talked about the Biot’s theory which adequately describes wave attenuation in shallow marine sediments, but underestimates seismic attenuation in rocks due to their low porosity. Weitao Sun and Diyao Wang of Tsinghua University and the Caofeidian Laboratory of China, presented their study of oscillatory flow which can modulate the gap-controlled resistance accelerating transit times and improve flow efficiency. A multinational team from the University of Denmark and Aker BP of Norway, led by Ermis Proestakis, presented a paper on the elastic response of a highly porous and mechanically soft siliceous mudstone from the North Sea during uniaxial compaction. This elastic response suggests that time-lapse seismic monitoring of P-wave velocity could identify compacted reservoir zones, supporting reservoir management strategies. Kasper van Wijk of the University of Auckland presented his findings about the applications of non-contacting laser ultrasound in rock physics. Ludmila Adam of the University of Auckland, New Zealand talked about the interpretation of moon and marsquake seismic data. Her team interpreted data recorded by seismometers deployed by NASA both on Mars and on the Moon. She pointed out that a combined laboratory, digital rock, and modelling approach shows that porous sedimentary rocks and fractured basalts can explain observed seismic velocities in the planetary bodies.

Keynote speaker for the session Rock Physics and Volcanology, Faults, Earthquakes, Dr. Doug Schmitt of Purdue University, USA, talked about the elastic anisotropy of the fractured alpine fault hanging wall and how to gain understanding from laboratory rock physics and borehole seismic. The knowledge about the state of fracturing near a fault from the observation of reduced wave speed and seismic anisotropy has the potential to constrain the hydrological and geothermal conditions in this zone. Matej Pec of MIT and his team of Harvard University and Ultrecht University presented the experimental studies of constraining the full energy budget of laboratory earthquakes. The energy budget of an earthquake is the balance of the energy consumed by the dissipative processes within the fault zone, radiated away by elastic waves and the work done due to or against gravity. His team’s study is the first to constrain the full energy budget of lab-quakes from an observational standpoint, providing critical insights into the dynamics of fault rupture and energy dissipation processes. Lionel Esteban and his team of researchers from CSIRO, Inpex, the Geological Survey of Western Australia and Edith Cowan University, Australia, learned about the microstructural transformations in both intact and mechanically fractured basalt samples sourced from Western Australia. Their findings highlight the complex interplay between fracture enhancement, mineral dissolution, and carbonate precipitation in governing CO2 mineralization potential and the long-term integrity of basaltic reservoirs. Mark Sams of IKON Science, Malaysia talked about the impact of gas on the elastic properties of shaley sands. Yazi Ali of the University of Auckland, New Zealand and his team explored how to address the lack of research on the link between cementation and strength by investigating how cementation influences rock strength in the East Coast Days Formation of Auckland sandstones using an integrated field laboratory methodology. Xiaodong Ma of the University of Science and Technology of China along with his colleagues proposed a novel inversion workflow using untapped borehole data. Hannu Seebeck and his colleagues at Earth Science New Zealand and the Ministry of Business, Innovation and Employment of New Zealand, reported on progress towards improving regional seismic velocity models which includes the characterization of New Zealand specific physical rock properties. These data contribute to the development of a new generation of high-resolution velocity models required for physics-based simulations of earthquake and tsunamis.

The organizers prepared a very exciting social program. The first get-together party was held in the Auckland Sky Tower which delivered an awesome view of the City of Auckland. The main workshop dinner was held in a beautiful local winery situated on Waiheke Island (Figure 1), a short ferry ride from downtown Auckland.

Figure 2: Hayward, B. W., Hopkins, J. L., Morley, M., & Kenny, J. A. (2022). Microfossil evidence for a possible maar crater and tuff ring beneath Rangitoto Volcano, Auckland, New Zealand. New Zealand Journal of Geology and Geophysics, 1-17.

A whole day was devoted to a guided geological field trip on Rangitoto Island (Figure 2) which is one of 53 volcanoes in the Auckland area. The field trip was guided by James Muirhead, a professional geologist from the University of Auckland. The group learned about the various phases of lava flows and the brave ones were taken into beautiful volcanic lava tubes.

At the end participants discussed the location of the next workshop. This time there were three candidates: China (a Beijing area university), Indonesia (close to Bali) and Canada (in the vicinity of Banff, Alberta). After an upbeat presentation made by Doug Schmitt, former professor at the University of Alberta, all votes went to Canada. So, the next 9th International Workshop on Rock Physics will be held in Alberta, Canada in 2028. Location and time to be determined.

Please contact authors for any research mentioned in the summary.