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Career Center Open House
Start:March 2, 2015 at 9:00 am
End:
March 2, 2015 at 12:00 pm
Location:
JGB 2.112 Martineau Career Services Suite
Contact:
Chelsea Ochoa, chelsea.ochoa@jsg.utexas.edu, 5122320893
JSG students, faculty and staff are invited to come by the Career Center for coffee and bagels.
Soft Rock Seminar - Reynaldy Fifariz
Start:March 2, 2015 at 12:00 pm
End:
March 2, 2015 at 1:00 pm
Location:
JGB 3.222
Climate Forum speaker series: Prof. Elinor Martin
Start:March 2, 2015 at 3:00 pm
End:
March 2, 2015 at 4:00 pm
Location:
JGB 3.222
Contact:
Kai Zhang, kzkaizhang@gmail.com
Elinor Martin (Assistant Prof. from Oklahoma Univ.)
Employer Spotlight Day: TCEQ
Start:March 3, 2015 at 10:00 am
End:
March 3, 2015 at 3:00 am
Location:
JGB 2.112 Martineau Career Services Suite
Contact:
Maurine Riess, mriess@jsg.utexas.edu, 512-232-7673
EMPLOYER SPOTLIGHT DAYS
A career services program designed to bring employers and students together in a relaxed, informative setting.
TCEQ will be on hand to visit with students and to talk about current full-time and internship openings.
Where: JGB 2.112 Career Center
Time: 10 a.m. to 3 p.m.
Students are welcome to stop by at any time during the day.
Refreshments will be provided. Business casual dress recommended.
Tech Sessions Speaker Series: PhD Talk
Start:March 3, 2015 at 4:00 pm
End:
March 3, 2015 at 5:00 pm
BEG Seminar
Start:March 5, 2015 at 10:30 am
End:
March 5, 2015 at 11:30 am
Location:
BEG Main Conference Room; Building 130; PRC Campus
Contact:
Sophia Ortiz, sophia.ortiz@beg.utexas.edu, 512.475.9588
View Event
William W. Simpkins
Professor and Chair, Department of Geological and Atmospheric Sciences
Smith Family Foundation Departmental Chair in Geology
Iowa State University
Abstract:
Enteric viruses have been observed in the Ames aquifer, an alluvial/buried valley aquifer composed of sand and gravel that supplies drinking water to Ames, Iowa (pop. 59,000). The focus of this study was the Downtown well field, where continuous pumping induces flow from the South Skunk River (SSR) nearly 1.4 km away into the well field. Because the SSR watershed contains 13 wastewater treatment plants and 109 swine CAFOs upstream, it was hypothesized that enteric viruses of both human and animal origin could be drawn into the well field by induced infiltration. The experimental design consisted of four sampling sites along a groundwater flow path at distances of 3.1 m to 2 km from the SSR. Velocity estimates predict that viruses would travel to Site D at the farthest point within two years. Fifty samples were collected and analyzed for adenovirus, enterovirus, norovirus, rotavirus, Bacteroides, and Hepatitis E virus (HEV), as well as Cl, ?18O, and ?2H, during seven sampling events (October 2011 to October 2012). Untreated sewage was sampled twice. Viruses were analyzed using real-time qPCR and RT-qPCR methods. At least one virus was detected in 42% of the samples, with groundwater showing detections in 39% of samples in the unconfined part of the aquifer next to the SSR and in 28% of the samples in the confined part of the aquifer. Adenovirus Subgroup A and HEV were the most frequently detected. Sewage samples showed the highest concentrations of adenovirus subgroups A and C, D, F, but contained no HEV. Sequencing showed adenovirus A31 to be the only serotype in the SSR and sewage; G3 HEV was the only genotype present and only in the SSR. This evidence suggests that the SSR is the source of G3 HEV (likely a swine source) and adenovirus A31 (human source) in the aquifer, thus confirming the original hypothesis about groundwater transport via induced infiltration. The occurrence of G1 norovirus and Campylobacter jejuni in two municipal wells, but not in the SSR, suggests possible entry through leaks in the sanitary sewer systems and/or well casing. In the case of enteric viruses in the Downtown well field, human enteric viruses come both river and sanitary sewer sources, while animal enteric viruses appear to come solely from the South Skunk River.
Tech Sessions Speaker Series: Owen A Anfinson
Start:March 5, 2015 at 4:00 pm
End:
March 5, 2015 at 5:00 pm
BEG Friday Seminar Series
Start:March 6, 2015 at 9:00 am
End:
March 6, 2015 at 10:00 am
Location:
BEG Main Conference Room; Building 130; PRC Campus
Contact:
Sophia Ortiz, sophia.ortiz@beg.utexas.edu, 512.475.9588
View Event
John R. Dribus
Global Geosciences Advisor
Schlumberger
Abstract:
Since the Macondo incident occurred in the Gulf of Mexico, the oil and gas industry has been diligent in following a three-step approach to addressing various drilling hazards that may be encountered in deep water: Identification, Prevention, and Mitigation. This presentation focuses on the important step of understanding the geologic origin of various hazards in deep water and around salt by reviewing the geologic origin, characteristics, and behaviors of the three deep water hazard types:
1. Man-made surface hazards including linear geometry and single site geometry hazards.
2. Sea-floor hazards including pockmarks, mud volcanoes, and mass sediment movement.
3. Sub-surface geologic hazards including shallow water flows, reactivated faults, and gas chimneys.
In addition, various potential drilling hazards may also be encountered when drilling massive salt and layered evaporates to reach prospective targets below. These challenges may occur when drilling:
1. Into the top of an allochthonous salt canopy (cap rock issues),
2. Through massive salt and layered evaporite complexes (including sediment inclusions, salt-to-salt sutures, and mobile layered evaporates), and
3. Emerging from salt or evaporites (including rubble zones, feeders, mobile bitumen) and other potential hazards.
UTIG Seminar Series: Brandon Schmandt, University of New Mexico
Start:March 6, 2015 at 2:00 pm
End:
March 6, 2015 at 3:00 pm
Location:
PRC, 10100 Burnet Road, Bldg 196, Rm 1.603, Austin, TX 78758
Contact:
Nick Hayman, hayman@ig.utexas.edu, 512-471-7721
View Event
“Seismic Structure beneath EarthScope’s USArray and the Origin of the Yellowstone Hotspot”
Abstract:
The seismic component of the EarthScope program includes >2500 broadband seismographs progressively deployed across the contiguous United States since 2005. The resulting data facilitate seismic imaging from the crust to deep within the mantle and are providing new insights into convective processes beneath North America such as the sinking and fragmentation of the Farallon slab and mantle upwelling beneath areas of intraplate volcanism such as the Yellowstone hotspot. Recent imaging indicates that the heat source for Yellowstone magmatism is rooted in the lower mantle and a buoyant plume is rising through a gap between fragments of the Farallon slab. A relatively local increase in broadband seismograph coverage near Yellowstone has also improved imaging of the crustal scale magmatic system, which shows two concentrated low-velocity anomalies thought to represent melt reservoirs in the shallow and deep crust.
Soft Rock Seminar - Eric Petersen
Start:March 9, 2015 at 12:00 pm
End:
March 9, 2015 at 1:00 pm
Location:
JGB 3.222
AAPG Distinguished Lecturer Seminar
Start:March 10, 2015 at 9:00 am
End:
March 10, 2015 at 10:00 am
Location:
BEG Main Conference Room; Building 130; PRC Campus
Contact:
Sophia Ortiz, sophia.ortiz@beg.utexas.edu, 512.475.9588
View Event
Chris Wojcik
Geophysical Advisor with Deepwater Exploration
Shell
Abstract:
Direct Hydrocarbon Indicator (DHI) support for hydrocarbons in the Niger Delta has been recognized for several decades. Largely unconsolidated Tertiary shallow marine and deepwater clastics are characterized by strong amplitude response related to hydrocarbon presence. Bright-spot amplitude anomalies have been an attractive exploration target since early 70s. However, even in a well-calibrated basin as the Niger Delta, amplitudes do not always ‘work’. Both false positives, as well as hydrocarbon-bearing reservoirs without any DHI support, are fairly common. The remaining exploration potential in the Niger Delta is still significant thus there is a clear driver to improve our ability to assess the potential for DHI support beyond classic bright-spot plays, as well as to polarize exploration risks to avoid costly failures.
The assessment of any seismic anomaly always includes an observational component and a predictive component. A comprehensive and robust predictive framework must be based on a detailed, geologically-driven integration of the available data across different scales, from a thin section to a seismic loopset, and with a good understanding of geologic controls of elastic rock properties. Key geological variables, such as reservoir and seal texture, pressure history and diagenesis, impact the type, magnitude and detectability of DHI’s. The rock properties knowledge and understanding of geologic controls can be organized into robust, basin or play-wide predictive frameworks enabling forward modeling of any subsurface scenarios and comparison with the actual seismic data in the prospective areas.
The classic Niger Delta bright-spot play can be considered mature, so there is a clear need to extend the amplitude-driven exploration to include other types of DHI’s such as dim spots and other more subtle anomaly types. The dim spot plays, with generally weaker hydrocarbon signal, are elusive, but they are recognized as holding large, generally under-explored potential. This paper presents an overview of key controlling factors that impact seismic response and cause rapid transition from bright spots to dim spots, and the transition from amplitude to AvO anomalies. Many clastic Tertiary basins globally follow similar stratigraphic and diagenetic evolution, thus the Niger Delta example may be a good analogue for subtle DHI plays elsewhere.
Tech Sessions Speaker Series: PhD Talk
Start:March 10, 2015 at 4:00 pm
End:
March 10, 2015 at 5:00 am
Tech Sessions Speaker Series: Mike Hudec
Start:March 12, 2015 at 4:00 pm
End:
March 12, 2015 at 5:00 pm
BEG Friday Seminar Series
Start:March 13, 2015 at 9:00 am
End:
March 13, 2015 at 10:00 am
Location:
BEG Main Conference Room; Building 130; PRC Campus
Contact:
Sophia Ortiz, sophia.ortiz@beg.utexas.edu, 512.475.9588
View Event
John Harju
Associate Director for Research
Energy & Environmental Research Center
University of North Dakota
Abstract:
Total oil in place estimates for the Bakken Petroleum System range from 300 billion barrels (Bbbl) to as high as 900 Bbbl. Estimates for primary recovery range from 3% to 12% depending on reservoir characteristics. When considering these low recovery factors in the context of such a large resource, it is clear that small improvements in productivity could increase technically recoverable Bakken oil by billions of barrels. While the use of CO2 in conventional reservoirs is a widely applied and well understood practice, its use for enhanced oil recovery (EOR) in tight oil reservoirs is a relatively new concept. In conventional reservoirs, heterogeneity, wettability, gravity, and relative permeability characteristics have a significant impact on the effectiveness of an EOR scheme, and fracture networks could be detrimental to EOR operations. In tight oil reservoirs, like the Bakken, which rely on fracture networks for productivity, the conventional notion of positive and negative attributes may or may not apply. A research program is being conducted to determine the viability of using CO2 for EOR in the Bakken. The key elements of the program include the development and integration of new and existing reservoir characterization and laboratory analytical data (core analyses, well logs, oil analyses, etc.) and static and dynamic modeling. Specific aspects of the project include
1) detailed geological characterization of selected Bakken reservoirs; 2) characterization of Bakken oils from the selected reservoirs; 3) laboratory experimental work to determine rates of hydrocarbon diffusion from Bakken matrix materials in the presence of CO2 under reservoir conditions; 4) static geomodeling, including the integration of multimineral petrophysical analysis, discrete fracture networks, and dual porosity-permeability elements; and 5) dynamic simulation of potential CO2 injection scenarios. Initial experimental data and modeling results indicate CO2 injection may substantially improve oil production while storing significant amounts of CO2. The results of this project are being used to plan and implement a pilot-scale CO2-based EOR test in a Bakken reservoir.
UTIG Seminar Series: John Snedden, UTIG
Start:March 13, 2015 at 10:30 am
End:
March 13, 2015 at 11:30 am
Location:
PRC, 10100 Burnet Road, Bldg 196, Rm 1.603, Austin, TX 78758
Contact:
Nick Hayman, hayman@ig.utexas.edu, 512-471-7721
View Event
“Interaction of Deep-water Deposition and a Mid-Ocean Spreading Center, Eastern Gulf of Mexico Basin, USA”
Abstract:
The general position of a Jurassic-Early Cretaceous spreading center in the eastern Gulf of Mexico has been suggested for many years, yet the precise location has not been defined. New seismic reflection and refraction data and plate reconstructions allows for delineation of this Tithonian to Valanginian age ocean ridge system and illuminate its prolonged influence on deep-water Cretaceous sedimentation. The extinct spreading center displays morphological characteristics associated with slow-spreading mid-ocean ridges: 1) large and wide axial valleys, ranging from 5 to 20 km wide; 2) deep axial valleys, often over 2 km deep; 3) normal faults that dip toward axial valleys; and 4) discontinuous, isolated basement highs, with elevations over 1km above regional oceanic basement depth that reflect local variations in magma supply.
Correlation from Florida Platform wells to this extinct spreading center confirms the precise time of oceanic crustal emplacement and thus estimation of spreading rate, consistent with plate reconstructions and morphotectonic observations. Reflections tied to the Top Haynesville-Buckner, Cotton Valley-Bossier, and Cotton Valley-Knowles downlap onto contemporaneous oceanic crust, confirming the depositional history of the area. These correlations imply that source rock intervals such as the Tithonian and Oxfordian are absent in a large portion of the abyssal plain south of the Florida escarpment.
The extinct spreading center remained a major element of the deep-water seascape, diverting sediment gravity flows during the Mesozoic. Pronounced depositional thicks occur north of the ridge line confirming that it acted as a partial barrier to seismogenic debris flows initiated by the Chicxulub impact but derived from the Florida Platform area.
The extinct spreading center and its associated seamounts are prominent structural highs that are draped by prospective Paleogene and younger reservoir intervals. Several of these features have been leased by oil companies for possible future drilling. Exploration here would test the outer limits of several Cenozoic play fairways, both from a reservoir and source rock standpoint.
Undergraduate Externships
Start:March 19, 2015
End:
March 19, 2015
Location:
Austin
Contact:
Chelsea Ochoa, chelsea.ochoa@jsg.utexas.edu, 512-232-0893
View Event
Participate in the undergraduate externship program! More information on externship sites can be found on GeoSource.
An externship is an unpaid career exploration opportunity for undergraduate students. Externs spend a day shadowing and learning at a host organization during an academic break. Hosts can be alumni or friends of the Jackson School, or companies looking to build their presence with students.
UTIG Seminar Series: Professor Thorsten Becker, UCLA
Start:March 23, 2015 at 12:00 pm
End:
March 23, 2015 at 1:00 pm
Location:
PRC, 10100 Burnet Road, Bldg 196, Rm 1.603, Austin, TX 78758
Contact:
Ian Dalziel, ian@ig.utexas.edu, 512-471-0431
View Event
“Structure and Dynamics of the Oceanic Plate System”
Abstract:
Seismic anisotropy in the Earth is strongest in the thermo-mechanical boundary layers of the mantle. There, observed variations in anisotropic patterns and strength should be straightforward to relate to mantle flow. However, both frozen-in and active mantle convection scenarios have been invoked, and recently fundamental assumptions about Earth’s lithosphere-asthenosphere domain have been challenged. Here, I first discuss to what extent paleo-spreading orientations explain the shallowest, lithospheric azimuthal anisotropy patterns. We detect a spreading rate and seafloor-age dependence of the degree of fabric establishment, with implications for how lattice preferred orientation (LPO) textures of olivine get frozen-in during plate generation. Associating asthenospheric anisotropy with active mantle flow, we explore several absolute plate motion (APM) models and show that a spreading-aligned (SA) model can provide a universal reference frame for present-day plate kinematics. The SA-APM model naturally approximates azimuthal anisotropy, matches hotspot kinematics, conforms to geodynamic constraints on net rotations of the lithosphere, and has implications for trench motion systematics. However, azimuthal anisotropy is best described when LPO is computed from actual mantle convection computations via texture formation tracking. A ~200 km thick layer of asthenospheric LPO alignment lies just below the ~1200 °C isotherm of half-space cooling, where this depth naturally defines a mechanical lithosphere. Yet, radial anisotropy and receiver function work appear to indicate a shallower boundary. We quantify these structural deviations from a thermally controlled lithosphere using new tomographic inversions and show that this “G” discontinuity sits on top of a strong radial anisotropy layer, which is also bracketed at the base by underside reflections. The bracketing depth range is consistent with estimates of melt mobility, indicating that the origin of the G, as well as Po/So scattering, may be partial melt layering, or alternatively petrological fabrics generated at the ridge. This may cause a mid-oceanic lithosphere discontinuity, similar to what is found in continental plates. While such structures speak to how oceanic plates are made, they appear to be dynamically irrelevant. This suggests that the traditional, first order model of the lithosphere-asthenosphere “boundary” as the base of a cooling half space system, albeit with regional variations and complexities due to reheating and effects of composition, provides a parsimonious explanation of a range of constraints.
Soft Rock Seminar - Joseph Levy
Start:March 23, 2015 at 12:00 pm
End:
March 23, 2015 at 1:00 pm
Location:
JGB 3.222
Climate Forum speaker series: Prof. Katharine Hayhoe
Start:March 23, 2015 at 3:00 pm
End:
March 23, 2015 at 4:00 pm
Location:
JGB 3.222
Contact:
Kai Zhang, kzkaizhang@gmail.com
Katharine Hayhoe (Prof. from Texas Tech Univ.)
Tech Sessions Speaker Series: PhD Talk
Start:March 24, 2015 at 4:00 pm
End:
March 24, 2015 at 5:00 pm
Employer Spotlight Day: PBW
Start:March 26, 2015 at 10:00 am
End:
March 26, 2015 at 3:00 pm
Location:
JGB 2.112 Martineau Career Services Suite
Contact:
Maurine Riess, mriess@jsg.utexas.edu, 512-232-7673
EMPLOYER SPOTLIGHT DAYS
A career services program designed to bring employers and students together in a relaxed, informative setting
Pastor Behling & Wheeler will be on hand to visit with students and discuss current openings.
Where: JGB 2.112 Career Center
Time: 10 a.m. to 3 p.m.
Students are welcome to stop by throughout the day. Refreshments will be provided.
Business casual dress recommended.
Tech Sessions Speaker Series: Julia Clarke
Start:March 26, 2015 at 4:00 pm
End:
March 26, 2015 at 5:00 pm
Evening of Thanks
Start:March 26, 2015 at 6:00 pm
End:
March 26, 2015 at 8:00 pm
Location:
Westin at The Domain
Contact:
Georgia Sanders, gsanders@jsg.utexas.edu, 512-471-1282
BEG Friday Seminar Series
Start:March 27, 2015 at 9:00 am
End:
March 27, 2015 at 10:00 am
Location:
BEG Main Conference Room; Building 130; PRC Campus
Contact:
Sophia Ortiz, sophia.ortiz@beg.utexas.edu, 512.475.9588
View Event
Dr. Svetlana Ikonnikova
Energy Economist
Bureau of Economic Geology
Abstract:
There are an increasing number of geologists and engineers that have become involved in shale gas research. However, the current fall in oil prices demonstrates how much the demand and funding for our research depends on energy prices. This talk will discuss in what way and to what extent shale gas drilling and profitability depends on economic parameters and how much it relies on other non-economic variables.
The talk will start with an overview of the key drivers for new shale gas/oil well drilling based on the discounted cash flow model. We will review the value of liquids, sensitivity to the natural gas price, and economic limit. Then, we will dig deeper and look at how operators may adjust to prices and keep their profitability by managing completion costs and by rationing drilling locations. The objective is to show in simple terms how economic parameters are integrated with engineering and geologic knowledge to support operator’s decision to drill. The role of geologic uncertainty as well as the knowledge of the major geologic attributes will be addressed.
UTIG Seminar Series: Pedro DiNezio, University of Hawaii
Start:March 27, 2015 at 10:30 am
End:
March 27, 2015 at 11:30 am
Location:
PRC, 10100 Burnet Road, Bldg 196, Rm 1.603, Austin, TX 78758
Contact:
Yuko Okumura, Yukoo@ig.utexas.edu, 512-471-0383
View Event
“The Climate of the Indo-Pacific Warm Pool at the Last Glacial Maximum”
Abstract:
During the Last Glacial Maximum (LGM), temperatures within the Indo-Pacific warm pool (IPWP) were cooler than today and precipitation patterns were altered, but the mechanism responsible for these shifts remains unclear. Previous proxy and model studies have emphasized the role of the Pacific Ocean, in particular changes in the zonal sea-surface temperature gradient driven by greenhouse gas forcing. In my talk I will present results showing the importance of the Indian Ocean, in particular changes driven by lowered glacial sea level. I will explore these ideas combining a network of 100+ proxy records with a multi-model ensemble of LGM simulations. This proxy-model synthesis suggests a key role for changes in tropical convection over the Sunda and Sahul shelves, which were subaerially exposed at the LGM due to the 120 m sea level drop. In the second part I will test this hypothesis using new climate model simulations performed with the Community Earth System Model Version 1 (CESM1). The simulations confirm that the changes in atmospheric circulation are initiated by the exposure of the shelves, in particular the Sahul shelf. More importantly, we find that ocean dynamical processes in the Indian Ocean amplify the response resulting in a large climatic reorganization in which a cold tongue develops in the eastern part of the basin, much like in the modern day Pacific. Last we explore the role of other LGM forcings, such as ice sheets and greenhouse gases (GHG). We find a role for northern hemisphere ice sheets, which explain the drier conditions in the northern part of the IPWP. The response to reduced GHG forcing shows wetter IPWP consistent with a stronger Walker circulation. This response is overwhelmed by the drying driven by sea level and ice sheets and therefore cannot be identified in the proxy data.
Few climate models participating in the Paleo Model Intercomparison Project (PMIP) are capable of simulating this response.
Soft Rock Seminar - David Brown
Start:March 30, 2015 at 12:00 pm
End:
March 30, 2015 at 1:00 pm
Location:
JGB 3.222
UTIG Special Lecture: Professor Demian Saffer, Penn State University
Start:March 30, 2015 at 12:00 pm
End:
March 30, 2015 at 1:00 pm
Location:
PRC, 10100 Burnet Road, Bldg 196, Rm 1.603, Austin, TX 78758
Contact:
Ian Dalziel, ian@ig.utexas.edu, 512-471-0431
View Event
“In Situ Stress and Pore Pressure Magnitude along Subduction Zone Megathrusts: Integration of Laboratory, Drilling, Geophysical and Numerical Modeling Approaches”
Abstract:
At subduction zones, mechanical loading due to burial and tectonic compression, in combination with the release of bound fluids by dehydration, can drive fluid pressures significantly in excess of hydrostatic. The resulting fluid overpressure drives flow and volatile transport through the forearc, and ultimately affects the strength of fault zones and wall rock, thus mediating in situ stress magnitudes, seismic behavior, and deformation style. Recent advances in documenting pore fluid pressure and effective stress magnitudes at convergent margins have come from drilling, seismic reflection surveys, and numerical modeling. Boreholes penetrating across the plate boundary at several subduction complexes, including Nankai, Costa Rica, and Barbados, have allowed quantification of effective stress and pore fluid pressure from observed compaction state and from laboratory reconsolidation tests on core samples. Likewise, drilling efforts coupled with laboratory measurements of rock strength have also yielded new estimates of in situ horizontal stress magnitude defined on the basis of wellbore failures and direct hydrofracturing experiments. At larger scales, pore pressure and horizontal stress magnitudes have been quantified using P-wave interval velocities from seismic reflection surveys, by application of laboratory- and field-based transforms linking velocity, porosity, and stress state. Numerical models, constrained by laboratory and drilling measurements, provide additional independent constraints on regional-scale pore pressure distribution. Finally, new and ongoing sub-seafloor observatory installations provide direct in situ measurements that serve as essential “ground truth”, while also documenting temporal variations in stress, strain, and pressure.
In total, these approaches show that low effective stress and highly elevated pore pressure (pore pressure ratios of ? = ~0.70–0.95) are common in the vicinity of the subduction megathrust at several margins, and that these conditions extend at least 30-40 km landward of the trench. In some cases, increased seismic reflectivity along the plate boundary is also correlated with regions of expected dehydration reactions or locations of high pore pressure estimated from numerical models, although this link remains unquantified and the underlying cause of the reflectivity is not fully understood. A simple non-dimensional analysis suggests that, globally, elevated pore pressure – and thus mechanical weakness – results from a dynamic balance between (a) geologic forcing that acts to drive pore pressure generation, and (b) hydraulic conductivity and drainage path length, which mediate fluid escape. Taken together, these findings provide a robust, quantifiable, and universal framework for understanding the role of fluids in the absolute strength of subduction megathrusts beneath the outer forearc. The high excess pore pressures and concomitant low effective stresses should suppress the nucleation of unstable slip, consistent with observations of fault failure by slow slip, afterslip, and very low-frequency earthquakes (VLFE) common to this region. Additionally, the low absolute strength of the plate boundary near its trenchward edge may offer an explanation for the propagation of rupture from below, potentially allowing coseismic slip all the way to the trench. Finally, in situ indicators of stress magnitude and orientation suggest that both horizontal stresses and slip on splay thrust faults are transient, and likely tied to the seismic cycle.
Tech Sessions Speaker Series: PhD Talk
Start:March 31, 2015 at 4:00 pm
End:
March 31, 2015 at 5:00 pm
Planetary Habitability Seminar SeriesApril, 22 2024Time: 1:00 PM - 2:00 PMLocation: PMA 15.216B UT Center for Planetary Systems Habitability Seminar Series. See website for speaker schedule and more details: View Events Join remotely: https://utexas.zoom.us/j/94052130734 In person: Classroom 15.216B, Physics, Math and Astronomy Bldg. UT Austin, Department of Astronomy 2515 Speedway, Stop C1400 Austin, Texas 78712-1205 |
UTIG Discussion Hour: Nicholas Montiel - PhD Talk (UTIG)April, 23 2024Time: 2:00 PM - 3:00 PMLocation: ROC 2.201 |
UTIG Seminar Series: Cornelia Rasmussen, UTIGApril, 26 2024Time: 10:30 AM - 11:30 AMLocation: PRC 196/ROC 1.603 Speaker: Cornelia Rasmussen, Research Associate, University of Texas Institute for Geophysics Host: Krista Soderlund Title: The Emerging Field Of Position-Specific Isotope Analysis: Applications in chemical forensics, exobiology, geo- and environmental sciences Abstract: Complex organics can be found all over our solar system and within each living thing on our planet, be it as part of its physiology or as a contaminant. However, different processes can lead to the formation of chemical identical molecules. This makes answering a number of scientific questions challenging. One example is distinguishing between biotic and abiotic molecules, hence hindering life detection on early Earth but especially on other planetary bodies, such as on Mars, Titan, Enceladus and on meteorites where organics have been detected. Moreover, tracing molecules as they move through the environment can be demanding, yet is essential in studying the flow of organic molecules as well as correlating pollutants with their source. Novel tools to address these challenges are currently being developed. Especially, the emerging field of position-specific isotope analysis is beginning to grant access to the unique intramolecular carbon (13C/12C) isotope fingerprint preserved in complex molecules. This fingerprint can be applied in various scientific disciplines, ranging from forensics to exobiology, geo- and environmental sciences, including geo health. Nuclear magnetic resonance spectroscopy (NMR) has the potential to become a key player in this research area, as it allows the analysis of organics within complex mixtures, all without the need to fragment the molecule into single carbon units or the combustion of the molecule of interest. We have been developing several NMR tools that allow us to investigate the intramolecular carbon isotope distribution within various molecule classes and to test the central hypothesis that the position-specific carbon isotope distribution within complex organics depends on a molecule’s source and formation history. |
Planetary Habitability Seminar SeriesApril, 29 2024Time: 1:00 PM - 2:00 PMLocation: PMA 15.216B UT Center for Planetary Systems Habitability Seminar Series. See website for speaker schedule and more details: View Events Join remotely: https://utexas.zoom.us/j/94052130734 In person: Classroom 15.216B, Physics, Math and Astronomy Bldg. UT Austin, Department of Astronomy 2515 Speedway, Stop C1400 Austin, Texas 78712-1205 |
UTIG Discussion Hour: Kristian Chan - PhD Talk (UTIG)April, 30 2024Time: 2:00 PM - 3:00 PMLocation: ROC 2.201 |