Events

UTIG Seminar Series: Dallas Sherman, UTIG

Speaker: Dallas Sherman, Postdoctoral Research Fellow, University of Texas Institute for Geophysics

Host: Eric Attias

Title: Geophysics in Sustainable Resource Development and Hazard Assessment: A Focus on Marine Electromagnetics

Abstract: Geophysics has an increasingly important role to play in developing resources and assessing hazards for a sustainable future. This talk will present select case studies highlighting the use of geophysics in general, and marine electrogmagnetics in specific, to this end.

As the clean energy transition gains momentum, the demand for rare earth minerals has driven industry to seek deposits with increased logistical difficulties. Geophysics is a key component in not only quantifying the ore body, but also in guiding infrastructure development, as demonstrated by exploration in remote northern British Columbia and Greenland.

Developments in marine electromagnetics has allowed for near-shore surveys in support of discovery and management of offshore fresh ground water reservoirs and assessment of relict permafrost conditions. A surface-towed controlled-source electromagnetic (CSEM) system used offshore Hawaii identified a new mechanism for fresh groundwater discharge, as well as the presence of freshwater plumes and a large offshore fresh groundwater reservoir. The same surface-towed system successfully mapped subsea ice-bearing permafrost on the Beaufort Shelf along 200~km of coastline, an important step in quantifying the climate change hazard posed by relict permafrost and its associated methane hydrate. Maps of depth to permafrost and its thickness were produced from electrical resistivity inversions. This system provides a cost effective method that could be used to further quantify permafrost extent, provide a baseline for measurements of future degradation, and provide observational constraints to aid in permafrost modeling studies.

UTIG Discussion Hour: Sara Sieberath (UTIG) & Malcolm Ross (BEG)

The UTIG Discussion Hour hosts weekly talks Wednesday afternoons at 2 pm CST. The Discussion Hour is a flexible format seminar hosted by UTIG and open to all members of our community. Presentations range from spotlighting new geoscience research to less technical talks sharing fieldwork excursions.

DeFord Lecture | Nicola Tisato

Earthquakes Under the Lens of  Rock Physics: From analog Materials in the Lab to Rocks in the Field by Dr. Nicola Tisato, Department of Earth and Planetary Sciences at UT Austin

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.

DeFord Lecture Series
Since the 1940’s, the DeFord (Technical Sessions) lecture series, initially the official venue for disseminating EPS graduate student research, is a forum for lectures by distinguished visitors and members of our community. This is made possible through a series of endowments.

UTIG Seminar Series: Xinting Yu, UT San Antonio

Speaker: Xinting Yu, Assistant Professor in Physics Astronomy, The University of Texas at San Antonio

Host: Krista Soderlund

Title: Deciphering the Nature of Titan’s Mysterious Magic Islands: The Role of Simple Organics

Abstract: In the ever-expanding world of planetary science, Titan, Saturn’s largest moon, stands as a realm filled with perplexing phenomena. One of the most enigmatic features is the so-called “magic islands” that appear and disappear on Titan’s liquid methane and ethane lakes. This talk will take you through a captivating investigation of how simple organics play a critical role in these ephemeral features. Building upon a comprehensive Titan material property database built by our group, this talk sheds light on the interactions between Titan’s atmospheric organic molecules and its lake liquids. The key focus will be on understanding whether these organic molecules float, sink, or do something entirely different once they make contact with the lakes.

Discover how atmospheric chemistry and thermophysical properties come together to unravel the fate of molecules like HCN, benzene, and ethylene when they hit Titan’s surface. Learn why some of these molecules may be responsible for Titan’s “magic islands,” while others find their resting place at the bottom of the lakes. By the end of this talk, you’ll gain insight into the complex interplay of atmospheric organic chemistry and planetary geology on Titan.

Planetary Habitability Series: Sascha Grziwa, University of Cologne

Speaker: Sascha Grziwa, Research Associate, Rhenish Institute for Environmental Research, Department of Planetary Research, University of Cologne, Germany

Host: Brandon Jones

Title: The upcoming hunt for exoplanets in the habitable zone: Advances in the detection of exoplanets in the context of the upcoming ESA space mission PLATO

Abstract: In recent years, thousands of exoplanets have been discovered, largely thanks to space missions such as Kepler and TESS. However, a significant number of these exoplanets possess relatively short orbital periods, ranging from 10-20 days, which are even more compact than that of Mercury, our innermost planet. This bias towards shorter orbits arises from the extended baselines required to detect exoplanets with more extended orbits, both in space missions and subsequent follow-up observations. This leaves our understanding of stellar systems, their evolution, and statistics somewhat incomplete, as knowledge of exoplanets with larger orbital periods are needed for full characterization. One way forward is developing new techniques like the detection of mono-transits to uncover longer-period targets in existing photometric data. But finally, there is a need for space missions with extended baselines to provide a comprehensive catalogue of planets with wider orbits to complete the picture.

PLATO, an ESA mission slated for launch in 2026 will primarily focus to monitor bright stars (m_v < 11) over several years, aiming primarily to detect Earth-like planets within the habitable zones of solar-type stars. In addition, the mission will observe more than 250,000 stars (m_v < 13) with the ambition of detecting up to 7,000 new exoplanets.

UTIG Discussion Hour: Dr. Leah Turner, UTIG

DeFord Lecture | Timothy Shanahan

Past to Future Climate: How can the paleoclimate record help us to understand the climate system and our future? by Dr. Timothy Shanahan, Department of Earth and Planetary Sciences at UT Austin

Abstract: TBD

DeFord Lecture Series
Since the 1940’s, the DeFord (Technical Sessions) lecture series, initially the official venue for disseminating EPS graduate student research, is a forum for lectures by distinguished visitors and members of our community. This is made possible through a series of endowments.

UTIG Seminar Series: Anieke Brombacher, Yale University

Contact costa@ig.utexas.edu.

Speaker: Anieke Brombacher, Postdoctoral Associate, Yale University

Host: Chris Lowery

Title: From individual life-history to species evolution: a case study with planktonic foraminifera

Abstract: Variation among individuals forms the raw material for evolution. During their lifetime, individuals can often adjust their state in response to environmental conditions. This plasticity in developmental history is hypothesized to stimulate the expression of novel trait combinations, increasing mean population fitness and accelerating local adaptation. However, very few empirical data exist to test this hypothesis on macroevolutionary time scales, as developmental history is often impossible to reconstruct from fossilized remains.

I use the exceptionally rich fossil record of planktonic foraminifera to study ontogenetic shifts in deep time. Foraminifera retain their entire life history inside their calcium carbonate shells, allowing for detailed morphometric analyses at different ontogenetic stages. Using morphological changes before, during and after speciation in the Menardella limbata – Menardella exilis – Menardella pertenuis lineage I studied changes to the timing of developmental processes. Using micro-CT scans, I plot individual chamber coordinates in xyz-space and reconstruct 3-dimensional growth trajectories with a new custom-made R package, Foram3D. The package functions calculate distances and angles between subsequent chambers, quantify trochospirality and reconstruct “Raupian” coiling parameters at every growth stage, and determine the number of chambers per whorl at the time each chamber was built.

The resulting developmental trajectories show that three-dimensional growth varies among species from the neanic and adult stage onwards. The angles between subsequent chambers increase after a species-specific size threshold is crossed, resulting in an increase in chambers in the final whorl and reduced chamber growth rates. Similarly, trochospirality (‘steepness’ of the shell spire) decreases at different chamber numbers among species, resulting in species-specific adult shell shapes. These results suggest that ontogenetic constraints can be overcome, resulting in novel morphologies and the emergence of new species.

UTIG Discussion Hour: Viscous Fluids at UTIG (National Queso Day)

DeFord Lecture | Elizabeth Catlos

Aftershock: New Insights into the Dynamics of Himalayan Orogenesis provided by the 25 April 2015 Nepal Earthquake by Dr. Elizabeth Catlos, Department of Earth and Planetary Sciences at UT Austin

Abstract: Since the pioneering studies of Himalayan tectonics, the orogen has been described as a fold-thrust belt with the most of the focus on the location, nature, and timing of its contractional structures. Lineaments within the Himalayan orogen were identified early on as remote sensing techniques advanced. Lineaments are relatively straight features expressed in topography and are not considered faults, or else they would be termed as such. Lineaments are often not included in orogen-scale maps and cross-sections of the Himalayas, although many of these features extend from the Indian craton and cut major Himalayan fault systems. After the devastating Mw 7.8 Gorkha earthquake on 25 April 2015 and its Mw 7.3 aftershock 17 days later, several geophysical studies identified the critical need to study Himalayan lineaments near the city of Kathmandu as two (Judi and Gaurisankar) appeared to influence rupture dynamics. These earthquakes were also unusual to the geologic community as their magnitudes were lower than predicted (Mw > 8 had been broadly advertised) and located far from the fault and decollement predicted to sustain the next major event. Unfortunately, most Himalayan lineaments are sparsely studied, and their locations are only published in papers or maps that are site-specific. This approach is a problem because lineaments appear to be significant in improving our understanding of Himalayan hazards. A new paradigm shift is also emerging in the aftermath of the devastating Nepal events, with Himalayan architecture appearing to be more like an accretionary wedge with internal microplates delineated by major Himalayan faults and nearby cross-cutting lineaments rather than a folded package of deformed and uniform lithological units. The Sikkim region of NE India is the first to be identified as a unique Himalayan microplate and the metamorphic history of its rocks helps develop new ideas regarding the assembly of the range.

DeFord Lecture Series
Since the 1940’s, the DeFord (Technical Sessions) lecture series, initially the official venue for disseminating EPS graduate student research, is a forum for lectures by distinguished visitors and members of our community. This is made possible through a series of endowments.

UTIG Seminar Series: Alice Turner, UTIG

Speaker: Alice Turner, Postdoctoral Fellow, University of Texas Institute for Geophysics

Host: Sean Gulick

Title: Lunar tectonics – insights from deep and shallow moonquakes

Abstract: During the 7-year operation of the Apollo seismic network, researchers detected and cataloged tens of thousands of seismic signals. This included signals from impacts, as well as shallow and deep moonquakes. The lunar seismic activity detected by these instruments, which are over 50 years old, still offers valuable information about the moon’s tectonics and dynamics. In this talk, split into two parts, I will discuss my work to unravel some of the puzzles of deep and shallow moonquakes.

Firstly, I will focus on deep repeating moonquakes. Deep moonquakes occur in clusters at 700–1,200-km depth and provide unique insight into the stresses deep in the lunar interior. Using observations of deep moonquake waveforms, I find tidal stresses to be the main driver of deep moonquakes. Based on these results, I intend to discuss the potential implications for lunar structure and the mechanism of deep moonquakes.

Secondly, I will focus on my recent work here at UTIG on shallow moonquakes. Classifying seismic signals correctly is key for evaluating the moon’s impact and seismicity rates. Yet, 60% of the original Nakamura et al. (1981) catalog events remain unclassified because the highly scattered lunar waveforms appear visually similar. In this work, we have developed a precise and quantitative method to distinguish between shallow moonquakes and impacts. Our preliminary results identify six features that differ between shallow moonquakes and impacts and suggest we may robustly and semi-automatically classify new or previously unclassified events.

Finally, I present my current and future research directions.

Planetary Habitability Series: Valerie De Anda, UT Austin

Speaker: Valerie De Anda, Provost’s Early Career Fellow and a Research Associate, Marine Science Institute, The University of Texas at Austin

Host: Brett Baker

Title: From Eukaryogenesis to Membrane Origins: using microbial metabolism as fossil record of early life

Abstract: The origin of eukaryotes (eukaryogenesis) and the lipid composition of cellular membranes (lipid divide) have represented the most contentious problems in biology for decades. Recent findings, such as the discovery of Asgard archaea, have provided new clues on the emergence of complex life. Asgard archaea are now considered the closest prokaryotic relatives of eukaryotes, yet little is known about the Asgard ancestor involved in the eukaryogenesis event (some 2 Gya). By using microbial metabolism as a fossil record of early life, we inferred the metabolic capabilities of the Asgard ancestor that gave rise to eukaryotes, including humans. Furthermore, we unravel another intriguing puzzle: the “lipid divide” which centers on the distinct lipid membrane compositions that separate bacteria and eukaryotes from archaea and how modern eukaryotes acquired their unique membrane-lipid composition. Drawing from the geological record we searched for genes that could explain the presence of steranes (fossilized lipids that are derived from sterols, a class of lipids produced by all major groups of eukaryotes). Until now, no archaea has been found to produce sterols in their membranes. By bridging different disciplines we identified for the first time sterol-like biosynthesis genes in Asgard archaea and verified their functionality through in vitro protein expression and lipid analyses. This is the first evidence of an experimentally diterpenoid cyclase in any archaea and the first to be described in Asgard representatives, providing new insights into the origin of membranes in complex life. Join us for a journey that transcends disciplinary boundaries and provides key insights into the prokaryote-to-eukaryote transition and the emergence of complex life on Earth.

Biography: Valerie De Anda is a 2023 Provost’s Early Career Fellow and a Research Associate in the Baker Marine Microbial Ecology laboratory at UT Austin. She uses microbial metabolism to understand the past, present, and future outcomes of life on Earth. Her research focuses on unraveling the chemical and metabolic principles of life across ecological and evolutionary scales to develop an understanding of microbial properties and their implication in a changing environment. She earned her BSc in Biology and her PhD in Microbial Ecology at the National Autonomous University of Mexico, both with summa cum laude. Her research has been published in high impact journals, including Nature, Nature Microbiology, and Nature Communications. Valerie has been invited to present her work in 10 countries at international conferences and universities and obtained several international awards. As a Mexican, first-generation female scientist, Valerie is committed to enhancing the representation and opportunities for women in science and other underrepresented groups. She believes that making science more diverse starts by awakening and empowering children and students that just need to see themselves reflected in real-life scientists from diverse backgrounds.

UTIG Discussion Hour: Mohammad Afzal Shadab, Oden Institute

DeFord Lecture | Prosenjit Ghosh

Carbonate Clumped Isotopes Thermometry: A new tool for addressing the hydrological cycle and ocean circulation during Miocene optima and climate transition by Dr. Prosenjit Ghosh, Indian Institute of Science

Abstract: Carbonate Clumped isotopes served as a unique tool for reconstruction of past temperature with confidence. This method has gained significant popularity amongst other competing techniques due to its ability to adequately define the temperature without knowing the isotopic composition of water. Nearly two decades of research engaged earth scientists in utilizing this new tool for addressing environmental condition for carbonate precipitation ranging from cosmos to benthos. The seminar will showcase a few new developments in the approach and provide a recent update on the scale for calibration of this novel tool for temperature assessment in carbonate samples from geological archives. Here, I will highlight some of our findings about environmental condition during mid Miocene and transition periods, which bear a large similarity with modern day Earth. The trends in hydrological conditions and extremes featured in the daily news channel broadcasts are encapsulated in the rock records preserved in the sedimentary libraries of the continental shelf and open ocean. We used the novel tool of clumped isotope thermometry on surface-dwelling planktonic foraminifera to investigate the thermal state of Miocene Ocean and the salinity condition over Indian Ocean, which are significantly influenced by the continental runoff and the biosphere.

DeFord Lecture Series
Since the 1940’s, the DeFord (Technical Sessions) lecture series, initially the official venue for disseminating EPS graduate student research, is a forum for lectures by distinguished visitors and members of our community. This is made possible through a series of endowments.

UTIG Seminar Series: Eric Dunham, Stanford University

Speaker: Eric Dunham, Professor, Department of Geophysics, Director, SDSS Center for Computation, Stanford University

Host: Demian Saffer

Title: Earthquake Swarms, Slow Slip, and Fault Valving in Coupled Models of Earthquakes and Fault Zone Fluid Transport

Abstract: Fluids and changes in pore fluid pressure in fault zones are thought to affect earthquake occurrence and fault slip behavior. Here we integrate fault zone fluid transport into earthquake cycle models to explore the coupled evolution of slip, pore fluid pressure, and fluid transport properties. We explore several models that account for the evolution of porosity and permeability in response to dilatancy, permeability enhancement during slip, chemical healing and sealing, and creep compaction. We also model the pore fluid pressure distribution along subduction megathrust faults by integrating petrologic modeling of dehydration reactions with mechanical modeling of up-dip fluid flow. The models produce fluid-driven aseismic slip, even for rate-strengthening friction, with many similarities to slow slip events, as well as swarm seismicity. We explore the relevance of these models to observations of slow slip events in subduction zones and to earthquake swarms (both naturally occurring and from injection), while also highlighting the need for additional experimental and geologic constraints to discriminate between the models.

Hot Science - Cool Talks: "Living Wonders of the Hill Country"

“Living Wonders of the Hill Country”

Discover the enchanting stories that make the Hill Country such a unique place. From colorful wildflowers to endangered species, an incredible variety of plants and animals call this region home. Learn about the importance of preserving the Hill Country’s biological diversity and leave with ideas for how you can make a positive difference. Copies of Dr. Hillis’s new book, Armadillos to Ziziphus, will be available for purchase on site—don’t miss the chance to get your copy signed after the talk!

David M. Hillis is the director of the Biodiversity Center at the University of Texas at Austin’s College of Natural Sciences. He was awarded a MacArthur Fellowship (aka the “Genius Award”) in 1999 and was elected to the US National Academy of Sciences in 2008. He is also known for his discovery of numerous new species, including Austin’s iconic Barton Springs Salamander.

Cool Activities: 5:30 – 6:40 p.m.

Talk with Q&A: 7:00 – 8:15 p.m.

Armadillos to Ziziphus Book Signing Post-Talk

Hot Science – Cool Talks provides front-row seats to world class research. For additional information about the Hot Science events, please visit http://www.hotsciencecooltalks.org.  

Tailgate - UT vs. Kansas

Tailgate 2023

WHEN: Saturday, September 30, 12:30-2:30pm
WHERE: Holland Family Student Center and Munib & Angela Masri Family Courtyard – Jackson Geological Sciences Building at 23rd & San Jacinto