Carl Heiland Lecture Series

Join us on the 15th St. cul-de-sac between Green Center and Hill Hall from 11:45 a.m. to 1:15 p.m. Tickets required. Pick them up in the Green Center Geophysics Front Office (GC 283) starting Monday, August 17. 

Seismic Monitoring at Utah FORGE: What We Have Learned and What is Next

Kristine Pankow, University of Utah
In-person: CTLM 102; Zoom link: https://mines.zoom.us/j/95432461641

Abstract
The Department of Energy Frontier Observatory for Research in Geothermal Energy (FORGE) program has a mission to enable research and advances in drilling and technology to facilitate a pathway for commercial Engineered Geothermal Systems (EGS). Dedicated seismic monitoring of the Utah FORGE site has been ongoing since November 2016 and is focused on both seismic hazard and on the development of the EGS reservoir. During this time, a local seismic network (a combination of surface broadband and accelerometer stations and shallow post-hole to borehole depth broadband/accelerometer/geophone stations) has been built, four deep (~1 to 3 km) seismic monitoring wells drilled, and as of July 2023, two deep (~3 km), highly deviated wells drilled. Additional temporary seismic experiments utilizing nodal geophones and DAS have also been deployed. In this talk, I will highlight some of the technical advances that have come from the drilling, discuss the development of the Utah FORGE traffic light system, and will present results of seismic monitoring of background seismicity, stimulations during 2019 and 2022, and seismic monitoring during drilling and circulation tests of the second deviated well in 2023. A focus of my research efforts at Utah FORGE is exploring the benefits and limitations of various scales and types of seismic deployment for both hazard and reservoir monitoring. I will highlight our results in the discussion of the various Utah FORGE activities. I will conclude with future planned activities at Utah FORGE and the planned seismic monitoring.

Speaker Bio
Dr. Kristine Pankow received her PhD in Earth Science with a Geophysics specialty from the University of California at Santa Cruz in 1999. Since 2000, she has worked as a seismologist at the University of Utah. She is currently the Acting Director of the University of Utah Seismograph Stations (UUSS) and is a Research Professor in the Geology and Geophysics Department. She also leads seismic monitoring for the Utah Frontier Observatory for Research in Geothermal Energy (FORGE). In addition, Dr. Pankow is the Board Secretary for the Seismological Society of America, is a member of the Utah Mine Safety Technical Advisory Council, and is the Advanced National Seismic System, Regional Coordinator for the Intermountain Region. Her current research interests include seismotectonics and related hazards in the Intermountain Region, improved seismic network operations, detecting and locating small- to micro-seismic events, source properties of small earthquakes, and better understanding swarm and triggered seismic sequences.

Characterizing an earthquake rupture barrier at the Gofar oceanic transform fault using controlled-source electromagnetic data

Christine Chesley

Remote only; Zoom webinar link: https://mines.zoom.us/j/95432461641

Abstract
Enigmatic earthquake patterns are observed at the Gofar oceanic transform fault (TF) off the East Pacific Rise. Repeat cycles of Mw ≥ 5.0 events appear to be separated by a “barrier zone”, which hosts prolific microseismicity but inhibits larger events from rupturing the entire fault length. The properties that allow this region of the fault to act as a rupture barrier zone are a topic of interdisciplinary research efforts.

In 2022, we collected controlled-source electromagnetic (CSEM) data from three ~30 km-long profiles that crossed the Gofar TF. Two profiles were located in the barrier zone, while the third straddled the seismically-determined division between the barrier zone and a rupture patch to the east. We inverted the CSEM data to determine the crustal resistivity structure of the TF. Our resistivity models reveal strong conductivity anomalies to the south of the TF in both the upper and lower crust. The sheeted dikes contain a sub-horizontal conductor, and a pipe-like conductor connects this shallow anomaly to a highly conductive (> 0.1 S/m) lower crustal body that dips and extends to the south of the TF.

Conductivity anomalies arise from interconnected conductive fluid (e.g., melt, seawater) and/or mineral (e.g, sulfides, clays) phases within relatively resistive crustal rocks. While the pipe-like conductor could indicate the enhancement of porosity due to brittle deformation in the TF domain, the amount of seawater or melt necessary to explain the deeper crustal anomaly is unreasonably large. We thus propose that the lower, and potentially upper, crustal conductors likely imply the presence of 1) brine and/or 2) saline magmatic fluids or brine with a small melt fraction. Given their confinement to the younger side of the TF, we suggest that the brines may have been generated during phase separation of seawater or magmatic fluids from an off-axis melt source (OAMS). We speculate that periodic injection of melt into the young lithosphere or suctioning of melt from adjacent ridges into transform domains may provide localized heat reservoirs that, when coupled with increased permeability from TFs, drive fluid flow where OAMSs are present. Elevated fluid circulation may increase pore pressure within discrete zones of TFs, promoting conditions that favor creep or microseismicity and impeding slip propagation.

Speaker Bio
Christine Chesley is a marine electromagnetic geophysicist and postdoctoral investigator at Woods Hole Oceanographic Institution. Her research areas center on characterizing the electrical resistivity and porosity of the oceanic lithosphere, including seamounts and oceanic transform faults, relating subduction zone processes to input material, investigating accretionary wedge dynamics, and estimating gas hydrate saturation in continental margins.

CATALOG: A United States National Laboratory Consortium for the Identification and Characterization of Undocumented Oil and Gas Wells

Chester Weiss
Sandia National Laboratories

In-person: CTLM 102; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

The U.S. Environmental Protection Agency estimates that methane emissions from over two million inactive, unplugged oil and gas wells, of which documented orphaned wells are a subset, range from a CO2 equivalent of 7-20 million metric tons per year, approximately the emissions of 2-5 million cars. Methane emissions from oil and gas wells, including orphaned wells, remain a significant driver of short term climate change – at least 25% of today’s warming is believed to be driven by methane from human activities. Under bipartisan infrastructure legislation, the U.S. Department of Energy established in 2022 the Consortium to Advance Technology to Assess Lost Oil and Gas wells (CATALOG, catalog.energy.gov), a national laboratory effort to accelerate technology transfer from the federal sector to move wells from the “undocumented” to the “documented” state, thereby enabling prioritization for well plugging and/or repurposing. In this presentation I will give a brief overview of the scope of the orphaned well problem, the organization and priorities within CATALOG, and recent technical achievements in the well identification task. You will learn that full accounting of the undocumented orphaned wells will require a reduction in cost and time-to-decision that is orders of magnitude lower than current state of practice. You will also learn that traditional geophysical reconnaissance and characterization techniques are one aspect of a much broader suite of analytical methods for finding and characterizing lost wells, and these data are being integrated with large-scale data scrapes of historical documents enabled by advances in GIS, machine learning and optical character recognition. Lastly, you will learn of outstanding challenges in the identification and characterization problem – working in rough topography, dense vegetation, absence of steel casing – that require novel solutions and continued research and development attention.

Speaker Bio

Dr. Chester Weiss (PhD, 1998, Geophysics, Texas A&M) is a cross–disciplinary scientist and recognized leader in computational geophysics, with a principal research emphasis on electromagnetic methods. Now at Sandia National Laboratories by Special Appointment as Distinguished Member of the Technical Staff (adjunct appointment at University of New Mexico, Department of Earth and Planetary Sciences), he previously held positions at Virginia Tech (Associate Professor of Geophysics), BP (Scholar in Residence), Scripps Institution of Oceanography (Greens Fellow) and Cambridge University (Visiting Scientist). He is the Sandia National Laboratories technical lead for DOE’s Orphaned and Abandoned Well Consortium. In 2022, he was honored with the Harold Mooney award by the Society for Exploration Geophysicists for technical excellence and “tireless support” of the Near Surface Geophysics community. He is a member of American Geophysical Union, Society of Exploration Geophysicists and was elected Fellow of the Royal Astronomical Society in 2002. He was Assistant Editor for Geophysical Prospecting (2003-09) and served as Assistant Editor (2009-11, 2016-2020) and frequent reviewer for Geophysics on the topics of electromagnetics, numerical modeling and fracture characterization. In 2018 he was chair-elect of the Near Surface Technical Section of the SEG and in 2020 was invited to serve on the Editorial Board of The Leading Edge where in 2022 he was elected Chair. When not working, he spends his time as a Certified Outdoor Emergency Care Technician and Ski Patroller while pursuing his lifelong passion for fitness, outdoor sports and adventure with his wife and twin nine-year-old boys.

Hydro-mechanical anisotropy in Oklahoma’s wastewater disposal reservoir from strain and fluid pressure measurements

Andy Barbour
U.S. Geological Survey

In-person: CTLM 102; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

In areas of induced seismicity, where earthquakes are triggered by human activities, such as wastewater disposal or hydraulic fracturing, hydromechanical properties in the subsurface can play a significant role in seismic hazard because of the interplay between crustal permeability, fluid flow, and frictional-failure mechanisms. I will discuss how the USGS has been using direct measurements of strain and fluid pressure to study the hydromechanical response of the Arbuckle wastewater disposal reservoir in Oklahoma. These measurements reveal significant leakage (vertical fluid migration) from the reservoir and anisotropic poroelastic coupling in response to external loading, which has implications for the accuracy of regional subsurface injection models, static and dynamic triggering mechanisms, and aftershock occurrence.

Speaker Bio

Dr. Andy Barbour received a BS in Mechanical Engineering from the University of California at San Diego and his PhD in Earth Science at the Institute of Geophysics and Planetary Physics at the Scripps Institution of Oceanography. He joined the USGS Earthquake Science Center as a Mendenhall Postdoctoral Fellow in 2014 and as a research geophysicist in 2016. Presently he leads the earthquake geodesy group, and his research focuses on understanding mechanisms for induced seismicity from wastewater disposal and ground deformation from geothermal energy production.

NEIC The Next Generation: Leveraging machine learning at the U.S. Geological Survey National Earthquake Information Center

William Yeck
USGS National Earthquake Information Center

In-person: CTLM 102; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

The U.S. Geological Survey’s National Earthquake Information Center (NEIC) leverages a wide array of seismic processing strategies to fulfill its mission to rapidly characterize and report global seismicity. The growing field of seismo-machine-learning continues to demonstrate that deep-learning algorithms have the potential to dramatically improve earthquake monitoring systems, but seismic networks must take care to ensure that the tools developed and employed suit their specific requirements. Near-real-time global earthquake monitoring is particularly challenging due to the wide array of observation variability, including tectonic setting, earthquake magnitude, instrumentation type and noise characteristics, and spatially and temporally variable network geometry. Deep-learning tools show particular promise due to their generalization abilities across all of these variables. The NEIC has developed and implemented its first generation of deep-learning algorithms into its operational system, including a regression model to improve the accuracy of automatic picks and classifiers to determine the phase-type and source station distance of automatically detected seismic phases. NEIC continues to conceptualize and develop new tools specific to its processing requirements, including models to rapidly estimate event magnitudes and robust pick uncertainty. In this presentation, I will give an overview of NEIC’s ongoing machine-learning developments and describe where NEIC can go next to develop a more automated, accurate, and rapid monitoring system.

Speaker Bio

Will Yeck is a research geophysicist with the NEIC at the Geologic Hazards Science Center in Golden, Colorado. His research focuses on the real-time detection and characterization of earthquake sources for rapid dissemination and investigations of significant earthquake sequences for long-term hazard assessment. His research is often directly aimed at improving the National Earthquake Information Center’s ability to detect and characterize global earthquakes, working on conceptualizing, developing, and implementing seismic processing tools. He also acts as an event coordinator at the NEIC, coordinating the response to significant earthquakes.

Distinguished Alumni Lecture

Nori Nakata
Massachusetts Institute of Technology

In-person: CTLM 102; Zoom link: https://mines.zoom.us/j/95432461641

The Antarctic coastal cryosphere is a complex and fascinating coupled system with global implications

Laurie Padman
Earth and Space Research

In-person: CTLM 102; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

This presentation aims to encourage a ‘systems’ approach to understanding ocean-ice interactions in Antarctic waters. The Antarctic coastal cryosphere consists of the edges of the grounded ice sheet, its floating ice shelves, icebergs, and various forms of sea ice. Recent research points to important, complex interactions between these components as they respond to atmosphere and ocean forcing, and tides. I first summarize some of the feedbacks that have recently been identified but not yet incorporated into coupled models. Then, as a detailed case study, I consider how grounded icebergs act as anchors for development of landfast sea ice and polynyas. These features then change ocean-atmosphere heat and freshwater exchanges to modify the properties of water masses that melt ice shelves, while landfast sea ice may also reduce iceberg calving. Potential feedbacks include: changes in iceberg calving rates and ice draft that alter the spatial distribution and frequency of groundings; and changes in coastal ocean stratification that modify the seasonal cycle of sea ice production and melt, the ability of subsurface warm water to intrude into sub-ice-shelf cavities, and the upper ocean heat available to melt thin ice-shelf ice in summer.

Speaker Bio

Dr. Laurie Padman is president and senior scientist at Earth and Space Research, a small research nonprofit based in Seattle. He received a PhD in Oceanography at the University of Sydney, Australia, in 1987, then spent 10 years on the research faculty at Oregon State University before moving to ESR. His research focuses on physical processes in polar oceans, including mixing and internal waves, tides, and ocean interactions with sea ice and ice shelves. He has also been involved in studies of variability of ice shelf elevation using radar and laser satellite altimetry and has been a member of the science team for both of NASA’s “ICESat” altimetry missions.

Objective Seismic Insight

Greg Partyka
OpenGeoSolutions

In-person: CTLM 102; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Seismic processing and imaging can reveal structure, stratigraphy, rock mass characteristics, discontinuities, and associated morphology and heterogeneity.

Resolution and detection requires:
– inversion to bandlimited realizations of target properties (leveraging AVO content to target and predict relevant rock and fluid properties), and
– decomposition of each realization into comprehensive sets of descriptive attributes/dimensions that respond to distinct characteristics.

The resultant attribute set should ensure that no available geologic content (that is available within the seismic signal) gets missed. A key principle of such characterization is to impart as little as possible subjective guidance (i.e., to objectively reveal the geological content without biasing the solutions via preconceived notions). This kind of processing and characterization can lead to huge data growth that can easily overwhelm the end user. Seismic processing readies the solution space, but it does not facilitate navigation and examination of the content. Effective exploration of the solution space requires comprehensive, intuitive, easy-to-use, real-time visualization that avoids problems associated with data access and data management. In this presentation, I will talk about
– characterization strategies for revealing the geological content, and
– a visualization approach that presents the information in a way that is objective and non-overwhelming.

Speaker Bio

Dr. Gregory Partyka received a degree in Geological Engineering from the University of Manitoba in 1987. From 1988 to 2007 he worked for Amoco, then BP, in Canada, Poland, the United States, and the United Kingdom. He has moved back and forth between assignments in operations and technology. This mix of roles allowed him to experience research, development, application, and just as importantly, the value that appropriate technology can bring to business decisions. Along the way, he focused his efforts on multidisciplinary problem solving and improving our ability to decipher geologic content embedded in seismic data. In 1996, he deepened his knowledge of reservoir characterization by participating in an intensive, year-long petrophysics training program. In 2003, he received the SEG Virgil Kauffman Gold Medal for developing spectral decomposition as a technique for reservoir characterization. In 2005, he was the the SEG Distinguished Lecturer. In 2007, he joined OpenGeoSolutions, where he continues to research, develop, implement, and provide services associated with exposing and extracting geological and engineering content that is embedded within seismic data. He was the Chairman of the SEG Distinguished Lecture Committee from 2007-to-2009 and served the SEG Council as representative for District 2. In 2012, he was awarded Honorary Membership to the Geophysical Society of Houston.

Natalya Gomez
McGill University

A cycle of memory creation, erasure, and phase transitions in granular assemblages sheared by natural faults

Dr. Vashan Wright
UC-San Diego

In-person: CTLM 102; Zoom link: https://mines.zoom.us/j/95432461641

Abstract:

A hallmark of many natural hazards is the transition in states that granular assemblages undergo, from structurally arrested to creeping to flowing. The frictional jamming theoretical framework predicts granular assemblages’ volume fraction and shear stress govern the transitions. This study uses x-ray microtomography to determine if the three-dimensional re-arrangement and fracturing of minimally disturbed fault zone grains, collected from two paleoseismic sites along the southern San Andreas fault zone that experience relatively differing shear stress magnitudes, record frictional jamming phenomenologies. The analyses reveal that the fault zone assemblages transition between one or more interrelated but geometrically localized and mesoscopic deformation states that change the assemblages’ stability during the seismic cycle. These states include (1) bulk grain re-arrangement, (2) localized grain re-arrangements, (3) individual grain fracturing, and (4) localized zones of grain fracturing. Grain re-arrangement is primarily a global phenomenon. Sorting exerts control over grain fracturing and re-arrangements. Co-seismic shear erases anisotropic fabric memory developed during aseismic shear and introduces its own (i.e., shear-hardened zones). One fault strand hosts gas bubbles or nematode burrows that record 300 years of tectonic deformation history after the ~Mw 7 ca. 1726 sSAFZ earthquake. Shear stress magnitude and elastoplasticity control memory creation and erasure and thus vary with the distance from a fault. Our findings imply that sheared fault zone grains experience a cycle of memory creation and erasure accompanied by varying deformation phase transitions (creeping, flowing, and structural arrest) and thus hold an invaluable record of how shallow faults influence grains as they slip co-seismically and aseismically.

Speaker Bio:

Dr. Vashan Wright is an assistant professor at Scripps Institution of Oceanography. He quantifies feedback between tectonics, paleoclimate, fluid flow, and the deformation of granular media deposited within marine, lacustrine, and coastal environments. To conduct this research, he examines granular media using seismic reflection and refraction profiles, sediment cores, aerial imagery, trenches, and x-ray microtomography. He integrates these data with numerical, experimental, and theoretical rock physics, fluid flow, and heat flow models to study tectonics, paleoseismicity, and earthquake-triggered geohazards.

Thanksgiving Holiday – No Heiland Lecture this week.

The Geophysics of Rubble Pile Asteroids

Daniel J. Scheeres
University of Colorado

In-person: CTLM 102; Zoom link: https://mines.zoom.us/j/95432461641

Abstract

Over the past few decades, there have been several missions that have explored small, rubble pile asteroids. The scientific exploration of these bodies is driven by their primitive compositions, which can contain materials that are largely unchanged from the formational epoch of the solar system. This has motivated a few sample return missions from these bodies to study the fundamental chemistry of the early solar system. However, the study of these bodies has also exposed many interesting aspects of, and questions about, the unique geophysical properties about these bodies. In fact, the study of the geophysics of rubble pile bodies is of fundamental interest for understanding key aspects of solar system evolution, including the formation of planetesimals across all regimes in the solar system, the unique and dynamic structures seen in planetary rings, and the formation of rubble pile asteroids following catastrophic collisions.

Given the unique environment about these small bodies, the determination and estimation of their mass distribution parameters and internal processes is challenging. These bodies balance gravitational, inertial and cohesive forces, while dynamical motion on and about them are also strongly perturbed by their irregular mass distributions and by exogenous forces such as from solar photon pressure. Despite the challenges of operating spacecraft in these environments, we have achieved significant insight into the internal structure of a number of these small bodies. These have provided unique constraints on their formation and overall evolution. In this talk the fundamental geophysical processes of small rubble pile asteroids will be presented, and several key exploration missions to these bodies will be reviewed and their results discussed. Finally, some future ideas for the continued exploration of rubble pile asteroid geophysics will be presented.

Speaker Bio

Dr. Dan Scheeres is a University of Colorado Distinguished Professor and is the A. Richard Seebass Endowed Chair Professor in the Smead Department of Aerospace Engineering Sciences at the University of Colorado Boulder. Scheeres is a member of the National Academy of Engineering, a member of the International Academy of Astronautics, and a Fellow of both the American Institute of Aeronautics and Astronautics and the American Astronautical Society.  Scheeres has studied the dynamics of the asteroid environment from a scientific, engineering and navigation perspective since 1992 and has been involved with NASA’s NEAR mission to asteroid Eros, the Japanese Hayabusa missions to asteroids Itokawa and Ryugu. He was a co-investigator on NASA’s OSIRIS-REx mission to asteroid Bennu where he led the Radio Science team, and is the PI for Janus, a NASA SIMPLEx mission that will launch two spacecraft to flyby two separate binary asteroids. Asteroid 8887 is named “Scheeres” in recognition of his contributions to the scientific understanding of the dynamical environment about asteroids.

Damien Jougnot