Carl Heiland Lecture Series

Our first Heiland lecture features two researchers from our Geophysics Department.

In-person: CK 140; Zoom link: https://mines.zoom.us/j/95432461641

Observations from the Seafloor: Low-frequency Ambient Wavefield Seismology on Large Nodal Arrays

Aaron Girard
Research Associate, Colorado School of Mines Geophysics

Abstract

Large-scale ocean-bottom node (OBN) arrays of thousands of multi-component instruments deployed over thousands of square kilometers have been used successfully for active-source seismic exploration activities at frequencies above 2.0 Hz. The analysis of concurrently recorded lower-frequency ambient wavefield data, though, is only just beginning. One objective of such ambient wavefield analyses is to exploit the sensitivity of naturally occurring sub-2.0 Hz energy to build long-wavelength elastic models to facilitate full waveform inversion (FWI). Doing so requires a detailed understanding of ambient wavefield information recorded on the seafloor including the types, frequency and effective source distribution of recorded surface-wave modes, the near-seafloor elastic model structure, and the sensitivity of recorded wave modes to model structure.

This talk will outline how using prestack ambient seismic data from the Gulf of Mexico and applying preprocessing and cross-coherence interferometry workflows allows analysis of ambient wavefields at (ultra)low-frequencies (defined as <1.0 Hz). The interferometric virtual shot gathers show evidence for Scholte, leaky Rayleigh and guided P-wave mode propagation between the 0.001-1.0 Hz. These waves remain coherent to distances of 80 km and have evidence of surface-wave scattering from shallow salt-body structure. Overall, these observations may have important consequences for the early stages of initial model building for elastic FWI analysis.

Speaker Bio

Dr. Aaron Girard completed his undergraduate degree in the Mines Geophysics Department, his MSc in the IDEA-League joint master program at TU Delft, ETH Zürich and RWTH Aachen, and his PhD at the University of Western Australia, where he explored imaging with ambient seismic wavefields. After graduation, he came back to Mines GP where he continues to develop methods for explorations with ambient seismic recordings.

From Rocks to Algorithms: Exploring Geoscience Through the Lens of AI and Machine Learning

Athos Nathanail
Post-doctoral Fellow, Colorado School of Mines Geophysics

Abstract

This presentation introduces a novel AI system that enhances geological data interpretation. This AI system efficiently learns from outcrop imagery and applies this knowledge to subsurface data like core samples, connecting surface observations with subsurface insights. It synthesizes these findings with geological literature to offer credible interpretations of depositional environments from single images. Such a system enhances the efficiency of routine geological interpretations, enables quantitative evaluation of interpretational uncertainty, and leverages consolidated domain knowledge from heritage records to add value.
The talk also explores the use of Machine Learning (ML) in enhancing Carbon Capture and Storage (CCS) assessments, aiming to establish a relationship between sonic velocity and CO2 saturation by refining petrophysical and geophysical log predictions. Additionally, the presentation highlights the development of ML tools for visualizing various data types, including lab results and well logs. The creation of software to enhance the resolution of seismic images using AI/ML techniques is also discussed. These innovations illustrate the potential of AI and ML to revolutionize subsurface exploration, risk analysis, and decision-making under uncertain conditions.

Speaker Bio

Dr. Athos Nathanail received his BSc in Petroleum Engineering in 2017 from the University of Wyoming, Wyoming, USA, and his MSc. in Reservoir Evaluation and Management in 2018 from Heriot-Watt University, Edinburgh, UK. He then continued to pursue his PhD and completed this in 2023 in Petroleum Geosciences from Heriot-Watt University, Edinburgh, UK. His previous work at the GeoDataScience Group focused on data science solutions for reservoir modeling, optimization, and uncertainty quantification. Dr. Nathanail specializes in integrating AI and ML in geosciences, enhancing geological interpretation efficiency, and scaling up routine tasks through AI-driven innovations.

Earthquakes through the lens of Rock Physics: from Analog Materials in the Lab to Rocks in the Field

Nicola Tisato
University of Texas – Austin

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Recent geophysical observations have revealed that faults and subduction zones deform through a complex spectrum of slip and deformation behaviors. Consequently, we still lack a full and comprehensive understanding of earthquake mechanics, limiting our ability to forecast earthquakes.

I will present and discuss the results of two research projects that shed light on Earthquake mechanics. Innovative rotary shear experiments paired with recordings of high-speed videos and acoustic emissions reveal that co-seismic slips trigger different weakening and strengthening mechanisms controlling the deformation along faults, suggesting that such dynamics may also be observed in seismograms. With the second study, I will show how rock-physics experiments, paired with CT scanning on sedimentary rocks from the Hikurangi margin, reveal how clay minerals play a fundamental role in controlling slow-slip events in the northern part of the North Island of New Zealand, providing help to mitigate earthquake geohazard.

Speaker Bio

Nicola Tisato is an assistantprofessor of Geophysics at the Earth and Planetary Science Department of University of Texas-Austin. He is a rock physicist and principal investigator of the Rock Deformation Laboratory. He earned his PhD from ETH Zurich in 2013 and a Master’s degree from the University of Padova in 2008. Nicola is a caver and loves mountains.

An Electromagnetics (EM) Guy working in Steel Casing: Nightmare, Opportunity or Both

Michael Wilt
Lawrence Berkeley National Laboratory

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Steel pipe and well casing are everywhere on the surface of the Earth. Most boreholes are cased with steel; steel pipe is also used for fencing and carrying various fluids around, as well as for electrical conduits. Although this is widely viewed as a nuisance to any electromagnetics (EM) field measurements, it is now understood that the subsurface pipe can provide access to deeper parts of the Earth, thereby allowing sensitivity to deeper target than would be available from the surface.

In this talk, I look at the challenges and opportunities of doing EM measurement within and around steel well casing. I show examples of where the casing is an issue for data collection and where it is essential for target sensitivity ― sometimes being the target of the measurements themselves. Finally, I look at what remains to be done in this new and emerging set of technologies.

Speaker Bio

A graduate from the Engineering Geosciences group at University of California-Berkeley, Dr Michael Wilt has worked with deep reading EM for the past 40 years. He worked in the Geothermal division at Lawrence Berkeley Lab in the 1970’s, in Earth Sciences at Lawrence Livermore lab in the 1990’s and joined Electromagnetic Instruments in the late 1990’s. He continued with Schlumberger after its acquisition of EMI in 2001 and retired from there in 2015. His emphasis has been on deep reading borehole EM including crosswell, surface-to-borehole and extended induction logging. He has worked for the past eight years as chief scientist at Groundmetrics and a staff scientist and contractor to build the deep reading EM capability at Lawrence Berkeley lab.

How Does Hydrothermal Alteration Change Volcanic Rock Properties?

Shreya Kanakiya
University of Houston

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Rock-fluid interactions ubiquitously occur in active tectonic environments and various reservoir settings. Understanding changes resulting from these interactions is vital for reservoir characterization, CO2 sequestration, and geohazards.

In this talk, I will discuss how hydrothermal alteration changes the petrophysical properties and corresponding geophysical signatures of volcanic rocks. Combining results from rock-fluid interactions in both a controlled lab environment and naturally altered rocks, I will show how the initial composition and fluid pathways in rocks can nudge the course of alteration and petrophysical changes. I will conclude by briefly discussing the open challenges to be explored ahead.

Speaker Bio

Dr. Shreya Kanakiya completed her undergraduate degree in Geology from St. Xaviers College and Physics from Jai Hind College in India. She then moved to New Zealand to pursue her Master’s & PhD from the Physics of Rock Lab at the University of Auckland where she studied rock-fluid interactions with implications for CO2 sequestration and volcano monitoring. After graduation, she held a postdoctoral position at the University of Houston and continues her work on better understanding the Earth’s dynamic subsurface. Her research interests lie in understanding hydrothermal processes that occur in the dynamic subsurface of high-risk active volcanoes, fault zones, and natural and man-made reservoirs using interdisciplinary lab techniques from geochemistry, rock physics, geomechanics, and paleomagnetism.

Asteroid Exploration and Space Resource Utilization

Rick Binzel
Massachusetts Institute of Technology

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Why do asteroids captivate such great scientific and public attention? It is because asteroids matter. Asteroids matter to scientists, to explorers, and to the future of humanity. Scientists across broad disciplines have come to recognize that understanding asteroids — and their relationships to meteorite samples in our laboratories — are essential to discerning the basic processes of planetary formation in our own solar system and beyond. For explorers, the nearest asteroids beckon as the most accessible milestones in interplanetary space, offering spaceflight destinations with lower propulsion requirements than the lunar surface. For futurists, the prospects of asteroids as commercial resources tantalize as a twenty-first-century silver and gold rush, albeit with far greater challenges and less certain rewards than faced by nineteenth-century Colorado pioneers. For humanity as a whole, it is not a question of if — but when — the next major asteroid impact will occur. While the disaster probabilities are thankfully small during any one lifespan (and miniscule within the time horizons typically considered by funding agencies), fully cataloging and characterizing the potentially hazardous asteroid population remains unfinished business. In this talk, we’ll review the growth of asteroid science from pinpoints of light to geological and geophysical worlds. Highlights will include the once-per-thousand year geophysical experiment opportunity presented by the near-Earth flyby of asteroid Apophis in 2029.

Speaker Bio

Dr. Richard P. Binzel is a professor at the Massachusetts Institute of Technology, recently retired from teaching in four MIT departments: Planetary Science, Physics, Aerospace Engineering, and Civil Engineering. His research continues, specializing in asteroids from the perspectives of science investigations and planetary defense by studying the physical characteristics of those objects whose orbits bring them within the vicinity of Earth.

Fiber-Optic for Environment Sensing (FORESEEx): from Urban to Arctic

Tieyuan Zhu
Penn State

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Fiber-optic sensing is increasingly utilized for subsurface resource exploration, near-surface geology characterization, and earthquake monitoring. Fiber-optic sensing offers three key advantages: dense sensors, centralized power system, and integration with existing telecom infrastructure, making it particularly beneficial for urban and remote areas. In this talk, I will introduce the Fiber-Optic Sensing for Environment Dynamics (FORESEEx) project, showcasing two Distributed Acoustic Sensing (DAS) experiments conducted in urban and Arctic environments. The urban study uncovers unique storm-induced signals, enhancing our understanding of storm processes. Additionally, in the second experiment conducted in Alaska, I will discuss newly discovered signals associated with glacial ice movement and ice-wedge cracking, offering valuable insights into their physical mechanisms.

Speaker Bio

Dr. Tieyuan Zhu is an associate professor in the Department of Geosciences at Penn State. Dr. Zhu received his PhD degree from Stanford University in 2014, and MS degree from Chinese Academy Sciences Institute of Geology and Geophysics, and BS degree from China University of Geosciences. He received Best Student Paper from SEG 2013, and J. Clarence Karcher Award from SEG 2018 for his contribution in advancing seismic attenuation theory and practice in seismic exploration. Dr. Zhu’s research is centered on the exploration of wave physics, particularly seismic and seismoelectric waves, as they relate to subsurface processes linked with energy and the environment. Recent projects involve the creation of real-time seismic monitoring techniques for geological stored CO2 plumes, the application of machine learning to seismic data for determining CO2/geothermal properties, and the development of fiber-optic seismology to better comprehend environmental dynamics.

From Medical Imaging to Exploration Geophysics: A Journey of CSI Technology

Chengbo Li
ConocoPhillips

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Compressive Sensing (CS) is a modern sensing theory in signal processing that revolutionizes how data is sampled and reconstructed. Originating in medical imaging, CS allows for the acquiring of fewer samples without compromising on the quality of the image or data, by exploiting the sparsity/redundancy of the data. This principle is particularly transformative in the field of exploration geophysics where efficiently sampling the subsurface is crucial yet often hindered by high costs and time constraints.

This presentation explores the application of CS principles in the development of the proprietary Compressive Seismic Imaging (CSI) technology, aimed at advancing seismic data acquisition and processing. It focuses on CSI’s adaptability and efficiency, underscoring its impacts in reducing operational costs and environmental footprint. Through real-world examples, the presentation demonstrates the practical benefits of CSI in exploration and development programs.

Speaker Bio

Chengbo Li, a mathematician and geophysicist, graduated from Nanjing University and obtained his Master’s and PhD from Rice University. At ConocoPhillips, his expertise in compressive sensing and optimization led to the development of the proprietary Compressive Seismic Imaging (CSI) technology. Li’s significant contributions in geophysics have been recognized with several prestigious awards, including the SEG Reginald Fessenden Award in 2021 and the Edith and Peter O’Donnell Award from the Academy of Medicine, Engineering and Science of Texas (TAMEST) in 2023, marking him as the first recipient in the field of exploration geoscience. He has also held influential positions in various committees and boards, serving the society of geophysics.

Biogeophysics: Geophysical Sensors for Biogeochemical Hotspots and the Search for Life

Estella Atekwana
AGU Fellow Distinguished Lectures

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Microorganisms are found in almost every conceivable niche of the Earth from hydrothermal vents in the deep ocean basins to the cold subglacial lakes of Antarctic ice sheets. As such, microorganisms have played an important role in transforming Earth systems over most of Earth’s 4 billion history. Understanding the dynamic and intricate microbial-rock interactions occurring at varying temporal and spatial scales requires non-invasive tools. The emerging field of Biogeophysics addresses this need, focusing on the study of physical changes in Earth materials catalyzed by microorganisms, observable through geophysical techniques. This presentation showcases how geophysical sensors serve as invaluable tools to sense subsurface microbial activities, ranging from cell growth and biofilm formation to biomineralization and biogeochemical cycling of elements. Future directions such as the search for life on other planetary bodies will be explored.

Speaker Bio

Dr. Estella Atekwana, the current dean of the College of Letters and Science at UC Davis, is a distinguished geophysicist renowned for her expertise in biogeophysics, near-surface geophysics, tectonics, and continental rifting. She previously served as dean at the University of Delaware’s College of Earth, Ocean, and Environment and as head of the Boone Pickens School of Geology at Oklahoma State University. She is a fellow of the American Geophysical Union and Geological Society of America. She is the recipient of outstanding educator awards from the Association of Women Geoscientists and the Society of Exploration Geophysicists. She received the 2021 Reginald Fessenden Award from SEG and the SEG 2020 Virtual Near Surface Global Lecturer award. She is a champion for developing a diverse talent pool in STEM and capacity building in developing countries.

Dr. Atekwana earned her BS and MS degrees from Howard University and her PhD from Dalhousie University, Nova Scotia, Canada.

The Adventures of an R&D Geophysicist

Albena Mateeva
Shell

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

For those of us who identify as researchers at heart, joining the industry may not be the most natural choice, but it can still lead to an exciting and fulfilling career. Mine is an example of a path that started in research and development (R&D) for oil and gas and led into the Energy Transition. By sharing it, I hope to benefit those on a similar journey. I was helped by the early realization that technical communication skills can be as important as mastery of geophysics (thanks CWP!) Another important realization was that one must articulate their wishes. Doing so got me involved in highly interesting work – from Virtual Source to DAS VSP and monitoring for CCS. The experience gained in mainstream geophysics then helped me take a leap to Nature Based Solutions for mitigating climate change. The role of geophysics there is still very new but of critical importance, as it aims to enable scaling up carbon sequestration monitoring in soils. It borrows on 4D insights gained in the oil patch. This is just one example, but a typical one, of valuable skills being acquired in oil & gas and applied in the Energy Transition.

Speaker Bio

Dr. Albena Mateeva holds a MSc in Physics (University of Sofia, Bulgaria) and a PhD in Geophysics (CSM – CWP’03). Upon graduation, she joined Shell R&D and has worked at the forefront of technology development ever since in the United States and The Netherlands. Among the multitude of recognitions for her work, she cherishes the most three SEG Best Paper awards. Currently, Albena leads technology development for monitoring carbon sequestration in soils. Albena is a champion for D&I and has three kids.

Subsurface Imaging and the Future of Geotechnical Site Investigation

Joseph Vantassel
Virginia Tech

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Traditional geotechnical site characterization relies on interpolating between limited 1D measurements of subsurface stratigraphy to develop 3D engineering models for design. The sparsity of traditional 1D geotechnical measurements presents challenges in geological settings with rapid spatial variation (e.g., alluvial deposits) and/or anomalies (e.g., karst formations). However, on-going efforts continue to show that non-invasive seismic imaging methods can be used to as a cost-effective means of improving geotechnical site investigation. This presentation will highlight some of this recent work to adapt and improve seismic imaging techniques to the problem of near-surface (i.e., depths < 30 m) geotechnical site investigation. The presentation will specifically emphasize work on improving uncertainty quantification and accelerating data-processing with artificial intelligence (AI). The presentation will highlight the application of techniques including the horizontal-to-vertical spectral ratio (HVSR), multichannel analysis of surface waves (MASW), and full-waveform inversion (FWI) to challenges including post natural-disaster reconnaissance, seismic site characterization, and cryosphere monitoring.

Speaker Bio

Dr. Joseph P. Vantassel earned his BS in Civil Engineering from Rensselaer Polytechnic Institute (RPI) in 2016. For his graduate studies, Dr. Vantassel attended The University of Texas at Austin, earning his MS in May of 2018 and PhD in December of 2021, in Civil Engineering. His graduate studies focused on the intersection of geotechnical engineering, geophysics, and computer science. After earning his PhD, Dr. Vantassel worked as a research associate in the Data Intensive Computing Group at the Texas Advanced Computing Center (TACC), until fall 2023. Dr. Vantassel is currently an assistant professor of geotechnical engineering in the Department of Civil and Environmental Engineering at Virginia Tech. He leads a group focused on advancing subsurface imaging toward more-robust and uncertainty-aware solutions through the intersection of field experiments, numerical simulation, artificial-intelligence, and high-performance computing.

Induced seismicity monitoring and source mechanism study in northeast British Columbia, Canada

Yajing Liu
McGill University

In-person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Seismicity related to fluid injection during unconventional oil and gas exploration has increased dramatically in North America in the last decade. In the western Canada sedimentary basin, most magnitude 3+ earthquakes are linked to high-pressure stimulation during hydraulic fracturing (HF), posing critical questions as to their triggering mechanism and seismic hazard implications. Using a local monitoring network in the Kiskatinaw area of the Montney Formation in northeast BC, we conduct an induced seismicity source property study of 8000+ earthquakes between 2017 and 2020. Local seismicity clusters exhibit spatiotemporal migration patterns consistent with HF stimulation along horizontal wells and/or fractures close to the wells. The dominant faulting style inferred from focal mechanism solutions highlights multiple cascading, shallow, strike-slip events and generally isolated, larger-magnitude reverse-style events in close proximity to the Fort St. John Graben system. Source spectral analysis suggests a constant stress drop of 1-10 MPa, with the self-similarity scaling breaking down at ML < 2.0, likely due to observational bandwidth limitation. We also developed a coupled poroelastic stress change and rate-state friction model to examine the relative roles of pore pressure, solid matrix stress and aseismic slip in triggering earthquakes on a pre-existing fault.

Speaker Bio

Dr. Yajing Liu received her BS in Geophysics from Peking University in 2001 and PhD in Earth and Planetary Sciences from Harvard University in 2007. She was a Harry Hess Postdoctoral Fellow at Princeton University from 2007 to 2009, and an assistant scientist at Woods Hole Oceanographic Institution from 2009 to 2011. She is currently an associate professor in the Department of Earth and Planetary Sciences at McGill University, and the Canada Research Chair in Earthquake Seismology. Her research focuses on integrating field observation and numerical simulation to understand the source processes of earthquakes and slow slip events.

Geophysical Modeling Meets Paleoseismology: Can We Know the Details of Past Cascadia Earthquakes?

Diego Melgar
University of Oregon

In-person: 4-6 p.m. Green Center, Friedhoff Hall
Reception with appetizers and drinks: 5:00-6:00 p.m.

Zoom link: https://mines.zoom.us/j/95432461641

This lecture is jointly sponsored by the Department of Geophysics, Department of Geology and Geological Engineering, and the U.S. Geological Survey

Abstract

Was the famous 1700 Cascadia earthquake a single magnitude 9+ plate boundary rupturing event? Or was it a series of ruptures closely spaced in time? What were the details of the slip distributions during those event(s)? These are fundamental questions which have persisted throughout the decades of study of the Cascadia subduction zone (CSZ). Answers to them impact how we think of the long term seismotectonic behavior of the margin and how we quantify its earthquake and tsunami hazards. In this talk I will showcase an approach which uses computationally efficient rupture and tsunami modeling to explore which kinds of earthquakes are parsimonious with the vast and diverse paleoseismic record at the CSZ. I will conclude that we do not know beyond a reasonable doubt that 1700 was a single event and that a sequence of ruptures should still be considered possible.

Speaker Bio

 Diego Melgar is the Ann and Lew Williams Chair in Earth Sciences and an associate professor of geophysics in the Department of Earth Sciences at the University of Oregon. He is also the director of the NSF-funded Cascadia Region Earthquake Science Center. His research focuses on large earthquakes where he works to understand the physics of the rupture process and how to best image it by using many diverse kinds of on-shore and off-shore geophysical data. Melgar researches the hazards associated with these large events, working on tsunami modeling and coastal impacts, as well as studying how strong shaking can be forecast.

He was awarded the 2016 Charles Richter early career award from the Seismological Society of America and the 2022 John Wahr early career-award from the American Geophysical Union’s geodesy section. He has served as member of the National Academy of Science’s Committee on Solid Earth Geophysics. Prior to joining the University of Oregon, he spent three years at the University of California-Berkeley’s Seismological Laboratory. Melgar earned his B.Eng. in geophysics from the Universidad Nacional Autónoma de México and his MS and PhD in geophysics from the Scripps Institution of Oceanography.

System-scale Airborne Electromagnetic Surveys in the Lower Mississippi River Valley Support Multidisciplinary Applications

Burke Minsley
U.S. Geological Survey

In person: BE 243; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

The lower Mississippi River Valley spans over 200,000 square kilometers in parts of seven states, encompassing areas of critical groundwater supplies, natural hazards, infrastructure, and low-lying coastal regions. From 2018–2022, the U.S. Geological Survey (USGS) acquired over 82,000 line-kilometers of airborne electromagnetic, radiometric, and magnetic data over this region to provide comprehensive and systematic information about subsurface geologic and hydrologic properties that support multiple scientific and societal interests. Most of the data were acquired on a regional grid of west-east flight lines; however, several high-resolution inset grids with line spacing as close as 200 m were acquired in targeted areas of interest. Additionally, 8,000 line-kilometers were acquired along streams and rivers to characterize the potential for surface water-groundwater connection, and another 6,000 line-kilometers were acquired along the Mississippi and Arkansas river levees to map this critical infrastructure corridor. I will present a summary of this large data collection effort, a new approach for joint interpretation of uncertainty in lithology and salinity using airborne electromagnetic and borehole data, and examples of how these data are being used to inform regional groundwater model development, inferences of groundwater salinity and coastal change, identification of faults in the New Madrid seismic zone, and characterization of levee infrastructure.

Speaker Bio

Dr. Burke Minsley joined the USGS in 2008 as a research geophysicist with the Geology, Geophysics, and Geochemistry Science Center in Denver, Colorado. After receiving a BS in Applied Physics from Purdue University in 1997, Burke began his career as a field geophysicist working on offshore seismic vessels before receiving a PhD in Geophysics from the Massachusetts Institute of Technology in 2007. His work at the USGS involves the development and implementation of innovative ground-based and airborne geophysical methods used in interdisciplinary studies to improve our understanding of Earth’s geosphere, hydrosphere, and cryosphere. Minsley’s projects are interdisciplinary and geographically diverse, including permafrost mapping in Alaska, and large regional groundwater availability and salinity studies in the lower Mississippi River valley, Delaware Bay, and Illinois River Basin. He also works on development of computational methods for uncertainty quantification in geophysical datasets and development of an open community data standard for geophysical data.