Talk About Geophysics!  TAG Webinar Series

EEGS’ Monthly Educational Webinar Series

EEGS has developed a new educational webinar series exploring topics ranging from scientific presentations to a deeper dive into noted authors’ published articles. The webinar series is intended to offer an informal setting and an interactive opportunity to address diverse geophysical topics. Students will be pleased to see that some scheduled topics will focus on career paths, working with your advisor, etc. and small business owners will benefit from sessions ranging from business technical tools to client management.

If you have questions, email [email protected].  If you'd like to suggest a future TAG Topic or offer to host a webinar, please click here (a short, online feedback form for EEGS' TAG Webinar organizers).  

All TAG Webinars begin at times based on US Mountain Time Zone. 

NEW:  If you find EEGS' TAG Webinar series valuable or you just want to support the program, please consider donating to the development of the webinars.  Just use the feedback/donation form to donate online.  Any amount is appreciated. 


June 2022 TAG Webinar
Investigation of Scale-Dependent Groundwater/Surface-water Exchange in Rivers and Lakes by Gradient Self-Potential Logging: Numerical Modeling and Field Experiments
June 8, 2022 

Presentation Title:  Investigation of Scale-Dependent Groundwater/Surface-water Exchange in Rivers and Lakes by Gradient Self-Potential Logging: Numerical Modeling and Field Experiments
Presenter:  Scott J. Ikard, U.S. Geological Survey, Texas Water Science Center
Date:  June 8, 2022
Time: 4:00 PM Mountain Time US (3:00 PM Pacific; 5:00 PM Central; 6:00 PM Eastern )

Registration Required!
Register in advance for this webinar:
https://us02web.zoom.us/meeting/register/tZEldOGtrD4iEtWyfWyG66sXHEV3MLnmmOMQ
Registrants will receive a confirmation email containing the link to join the webinar. 

Presentation Description:
Exchanges of groundwater and surface-water are fundamental to a wide range of water-supply and water-quality management issues but challenging to map beyond the reach scale. Waterborne gradient Self-Potential (WaSP) measurements are directly sensitive to water flow through riverbed and lakebed sediments and can be used to infer exchange locations, direction (gain versus loss), physical scale, and relative spatial changes, but to date applications to river corridor hydrology are limited. Numerical modeling and field experiments were therefore performed herein, each emphasizing WaSP logging for identifying and locating focused and distributed vertical groundwater discharge (surface-water gain) and recharge (surface-water loss) in rivers and lakes. Two and three-dimensional numerical models were constructed to simulate the polarities, appearances, and peak amplitudes of streaming-potential and electric-field anomalies on a riverbed or lakebed, and in the surface-water, that were attributable to steady-state vertical fluxes of groundwater through the bed sediments. Effects of varied hydraulic length-scale of exchange and surface-water depth were tested through numerical modeling. Modeling results aided in data acquisition and interpretation for field experiments performed along a 1.5 – 2.0 kilometer reach of the Quashnet River in Cape Cod, Massachusetts, where focused, meter-scale groundwater discharges occur at discrete locations within otherwise ubiquitous and more diffuse groundwater upwelling conditions, and along a 31-km long reach at Lake Travis, Austin, Texas where the Colorado River is incised into the lower and middle zones of the Trinity aquifer. Strong gradient SP anomalies were repeatedly measured in the Quashnet River at previously confirmed locations of focused groundwater discharge, and in Lake Travis at locations of submerged springs and regional fault lines, showing the efficacy of waterborne gradient SP logging in identifying groundwater/surface water exchanges at multiple spatial scales. 

Biography:
Dr. Ikard is a licensed Professional Engineer and Geologist. He holds a B.S. in Geology and Mathematics from James Madison University, an M.E. in Geological Engineering from the Colorado School of Mines, and a Ph.D. in Geophysical Engineering from the Colorado School of Mines. He is a Hydrologist and Project Chief in the Geophysics and Subsurface Analysis unit of the United States Geological Survey's Oklahoma-Texas Water Science Center, in Austin, Texas. Scott leads applied research studies that entail geophysical and hydrologic surveying, instrumentation and data acquisition and data processing, and analysis and publication of airborne, waterborne, surface, and borehole hydrogeophysical data.

 


2022 TAG Webinar Presentations History

May 11, 2022 TAG Webinar:  A Framework for linking Geophysical and Geotechnical Observations

Mark Vardy, MSci. MRes PhD of SAND Geophysics outlined a proposed framework that can be used to link geotechnical and geophysical observations in a semi-quantitative manner not to be considered a definitive method or workflow for translating geophysical observations into equivalent geotechnical observations but rather, to be considered a geoscience Babel fish, bridging the communication gap between geophysicists and geotechnical engineers, allowing users/interpreters to understand how observed spatial and/or stratigraphic changes in one set of parameters are likely to be reflected in other parameters.  EEGS is grateful to Dr. Vardy for presenting and the questions answered at the conclusion of his presentation.


 

2022 TAG Webinar Presentations History

April 13 TAG Webinar:  A Multi-Geophysical Case Study of a Karstic Aquifer 

Mustafa Saribudak, Ph.D., Environmental Geophysics Associates (EGA), presented his case study on Barton Springs, a major discharge site for the Barton Springs Segment of the Edwards Aquifer and is located in Austin.  On behalf of EEGS and the large TAG Webinar audience, Dr. Saribudak was thanked for the presentation and follow-up question and answer session.


2022 TAG Webinar Presentations History

February TAG Webinar:  Leading the Way to Inclusion

Julia Potter, Call & Nicholas, Inc. and Mario Munoz, University of Arizona presented the latest news and accomplishments of the Arizona Chapter of Women in Mining, which focused on diversity, equity and inclusion (DEI) in the mining and mineral resources industries.  They also shared how individuals can contribute to more inclusive organizational cultures.  An engaging question and answer session followed.  Moira Poje, chair of EEGS' Diversity, Equity and Inclusion Task Force, thanked the February TAG Webinar presenters Julia and Mario for their inspiring and informative presentation.


2022 TAG Webinar Presentations History

January TAG Webinar: Geophysical Exploration of a Historical Stamp Mill Dump for the Volume Estimation of Valuable Residues

Tina Martin, 2020 Alan Witten Best Paper award winner, presented her paper "Geophysical Exploration of a Historical Stamp Mill Dump for the Volume Estimation of Valuable Residues" during a well-attended January webinar.  Presented was an approach for the estimation of ore processing residue volumes in a historical mine waste dump by combining electrical resistivity tomography (ERT), ground penetrating radar (GPR) and spectral induced polarization (SIP) flanked by mineralogical studies, enabling Ms. Martin and her colleagues to distinguish between valuable and non-valuable waste material and to calculate the volume of the ore processing residues, which can be used further for the determination of the economic potential from the remaining metal content.  (The Journal of Environmental and Engineering Geophysics (JEEG) offers an opportunity for published authors to earn a yearly Best Paper Award in honor of Alan Witten. The Best Paper Award is decided by the EEGS board of directors after a recommendation from the current JEEG editor. The award is presented yearly at SAGEEP.)


2021 TAG Webinar Presentations History

December TAG Webinar:  Best of the Proximal/Remote Sensing Soil Investigation Symposium

Harrison Smith (University of Arkansas), Felippe Hoffmann Silva Karp (McGill University), and Steven van der Veeke (University of Groningen) served as December's TAG Webinar presenters.  The three presenters were the “Application of Proximal and Remote Sensing Technologies for Soil Investigations” virtual symposium's best student presentation award winners.  The virtual symposium was a collaborative effort between the International Union of Soil Sciences – Proximal Soil Sensing Working Group, the Society of Exploration Geophysicists, and EEGS.  Approximately half of the 45 research presentations given at this symposium were provided by students, their quality termed by the Technical Committee as "outstanding."  EEGS was proud to feature the winners at its December TAG Webinar, and, based on the Q&A session and feedback, very well received by the webinar participants!   

November TAG Webinar:  Careers in Near-surface Geophysics

A panel of six professional geophysicists led a discussion on their careers and trends in geophysics on Nov. 10.  Bart Hoekstra, Dan Glaser, Esther Babcock, Evgeniy Torgashov, Katherine Grote, and Craig Murray represented a wide range of positions and roles in geophysics and shared their experience, education and professional development path with participants.  Great questions, as one panelist termed them, were posed by participants, adding to the value of the experience.     

October TAG Webinar: GeoLatinas presenters and members

On October 13, EEGS welcomed Adriana Crisóstomo Figueroa and Alma Vázquez-Lule of GeoLatinas to TAG Webinars.  GeoLatinas is a grassroots organization building bridges towards equity, diversity, inclusion and accessibility in the geosciences.  EEGS' Task Force DEI (Diversity, Equity and Inclusion) Chair, Moira Poje, hosted the event, presided over the question and answer session and thanked the presenters for their informative overview of GeoLatinas, its work to inspire and support those currently engaged or working in earth and planetary sciences, and impressive list of initiatives and accomplishments.     


September TAG Webinar - Magnetic Surveying for Man Made Objects – Theory 

On September 8, Gretchen Schumauder and Bart Hoekstra hosted a pre-recorded presentation by Becky Bodger, Seequent Limited, and Stefan Burns, Bart Hoekstra and Gretchen Schumauder from Geometrics Inc. This was the first in a series about magnetic surveying for anthropogenic objects and focused on the practical implications of magnetic theory for conducting surveys.  Following the pre-recorded presentation was a question and answer session hosted by Gretchen and Bart.  


August TAG Webinar - G2HE - Transforming Geophysical Parameters into Hydrogeological and Engineering Parameters and the Relevance of the Factors of Empiricism, Scalability, Resolution, Uncertainty, Clay and Experience

On August 11, attendees participated in EEGS' August TAG Webinar and an extended question and answer period.  Organizers thanked Mr. Pettifer for his interesting title and informative presentation.  


July TAG Webinar - Characterizing a Physical Model of a Collapsing Void Using a Trapdoor and Time-Lapse Surface-Wave Analysis

On July 14, Sarah Morton Rupert presented findings from a laboratory text box using a physical model designed to simulate void roof failure and migration to the ground surface to support the conceptual model that Vs variations can be an indicator of stress-field variations in the roof structure above a void and used to map the progression of a collapsing structure.  Questions and Ms. Morton Rupert's responses rounded out the well attended webinar.  Organizers and attendees thanked Ms. Morton Rupert for presenting her award-winning presentation with EEGS TAG Webinar participants.   

May TAG Webinar - New Frontiers in Near Surface Geophysics: Muons, Cosmic Ray Neutron Probes, and Hyperspectral Imagery

On May 12, Leon DuPlessis, formerly with Freeport-McMoRan Inc., Trenton Franz, Univ. of Nebraska, and Isabel Barton, Univ. of Arizona presented three very interesting and informative talks and answered participants' questions.  Dr. DuPlessis spoke about Subsurface Density Mapping Using Muon Technology; Dr. Barton presented Mineral Mapping Using Drone-Based Hyperspectral Imaging;  and Dr. Franz summarized the Opportunities and Challenges Towards Integration of Hydrogeophysical Sensors in Agriculture.  TAG Webinar organizers expressed their appreciation to all three presenters for a very well received event.


April TAG Webinar -  Proximal Soil Sensing: State of the Science

Dr. Craig Lobsey, senior lecturer in mechatronic engineering at the University of Southern Queensland, University of Southern Queensland presented his perspective on some of the key challenges in the application of sensor technology for soil management, recent developments and what may be on the horizon for proximal soil sensing technology.  Organizers extended many thanks to Dr. Lobsey for his talk as well as a robust question and answer session which followed.  


In March, EEGS held SAGEEP 2021 - held virtually March 14-19, 2021.


February TAG Webinar - Meet Me Halfway

The EEGS Task Force Diversity, Equity and Inclusion (DEI) takes advantage of every opportunity to raise awareness and take a lead role in setting and achieving the highest standards of integrity, fairness, dignity and respect. Therefore, February's TAG webinar series featured a Task Force DEI webinar:  Meet Me Halfway, an interactive webinar exploring intergenerational communication in a geophysics workplace.  EEGS President Barry Allred commented: "Thanks to all the Task Force members for your efforts putting together the TAG webinar. It was excellent, well organized, and the discussions in the breakout rooms were very interesting and insightful.  I think everyone really enjoyed the interactive webinar format."

The webinar slide presentation is available for viewing by clicking here.


Inaugural January TAG Webinar a Success!

TAG's first webinar was held on January 13 and welcomed guest speaker, G. Didem Beskardes, the JEEG's 2019 Alan Witten Best Paper Award recipient.  By all measures - audience participation, attendee feedback and content quality - the TAG Webinar was successful and well received.  Dr. Beskardes discussed her findings from the study published in the JEEG paper "Power Density Distribution in Subsurface Fractures Due to an Energized Steel Well-casing Source" and conducted a lengthy and insightful Q&A session.