EAGE Education Tour 7 Portland - Prof. Peter Styles

Environmental Geophysics: Everything you ever wanted (needed!) to know but were afraid to ask!

Date
17 - 17 March
Location
Portland, Oregon, United States
Registration
Closing soon
Call for papers
Closed

Course Description

EET 7 - Environmental Geophysics: Everything You Ever Wanted (Needed!) to Know but were Afraid to Ask!

Instructor Prof. Peter Styles (Keele University, UK)
Duration 1 day
Disciplines Environmental Geophysics
Level Foundation
Language English
Book Available in EAGE Bookshop
CPD Points
5

Course description 

There are many excellent books and some courses dealing with Environmental/Near Surface Geophysics but they are all INWARD facing, i.e., aimed at Geophysicists and students of Geophysics and not truly accessible to the stakeholders and commissioners of Environmental Geophysics. This is a serious problem because much Environmental/Engineering Geophysics is commissioned by other disciplines, most notably Civil Engineers, Water Engineers, and Nuclear Engineers amongst others, where lack of clear communication can lead to ill-defined and inappropriately specified tenders and which, whilst the work may be adequately carried out, may still not deliver the desired information. This is an OUTWARD facing course for people who need to understand Geophysics because it can solve their problems and will be driven by problems regularly encountered and their optimal geophysical solution in collaboration with the essential but last to be applied intrusive investigation.

The people who need this course do not require a great understanding of the mathematical basis of geophysics but they do need to understand the physical principles and what techniques will do what and where they fail and why and what information can be gleaned from Geophysics and what are the limitations and boundaries of interpretation.

What is really important is how we combine techniques in a truly integrated way to solve subtle, complex and critical problems that one technique alone cannot satisfy.

 

Course outline

In order to understand the physical, hydrological, and pollution situations which are present in the near subsurface, (often due to past industrial activity and presenting a need to regenerate safely) it is critical to be able to interrogate the shallow subsurface. In previous times this was done by trial pitting, drilling and excavation but the nature of the problems mean that these intrusive techniques, while essential for ground truthing, can liberate or compromise the very ground we are seeking to make safe. Therefore, legislators and developers are turning more and more to non-intrusive geophysical techniques to characterize the subsurface in order to make informed decisions as to where and how many intrusive confirmations (i.e., boreholes) are needed to obtain sufficient comfort to plan a strategy for remediation/containment or abandonment. Poor specification, poor advice, lack of knowledge about the appropriateness or otherwise of the tools available to address the task, adherence to methods which are defensible in litigation rather than right for the problem have all led to a position where there is a lack of trust between Engineers, who are usually in the position of client and Environmental Geophysicists, who are usually the contractor. It is not just the fault of the Purchaser; with the advent of much more automation in geophysical instrumentation there are practitioners who carry out surveys without a full understanding of what, where, why and in what order and also make promises which cannot be delivered because of the constraints imposed by the fundamental laws of physics. The scale of task (and financial risk) that Environmental Geophysics is being required to address is also growing exponentially; I sit on the Nuclear Decommissioning Agency Geosphere Characterization Panel and have become acutely aware that legislators such as the UK Environment Agency, Health and Safety Executive, Nuclear Installations Inspectorate impose strong controls on the number and position of exploratory boreholes in projects such as the site characterization and investigation for Radioactive Waste Geological Disposal Facilities and are relying on geophysics in all its forms to deliver the information on which siting, safety case , post closure safeguarding will be designed and delivered. Exactly the same will occur for Underground Gas Storage and Geological Sequestration of CO2 where monitoring of retention and stability are paramount. The days of claiming that 'only the drill will prove it' are fading as the drill will only be applied at a very late stage and NOT where the critical facility itself will be situated for fear of compromising the safety case. New sources of energy from Coal bed Methane and Underground Coal Gasification will also require remote monitoring of areas which CANNOT be investigated by intrusive techniques.

This course will address:

  • The nature of Geophysics, the range of problems that can be addressed by it, what can be seen and what cannot and the limitations imposed by the laws of physics and 'environmental noise'.
  • Problems such as Natural and Man-Made Cavities in Coal, Chalk, Limestone Karst, Salt and other Evaporites and their collapses, either potential or incipient. Their detection, characterization, geometries and state of stability and verification of the quality of their remediation. Brownfield site characterization and the scale of remediation necessary; LNAPL and DNAPL pollutants and leachates, buried infrastructure, archaeological features. Determination of engineering properties, topography, layering, strength and rippability of soil/bedrock. Monitoring gas storage and CO2 sequestration underground using microgravity and microseismic techniques
  • How to detect sub-surface 'trouble ahead'! Techniques: When, Where and How They Should Be Used and When Not!
  • Potential Field Techniques: Gravity and Magnetism, their similarities and differences, instrumentation, field methodologies for high resolution and accuracy, interpretation, target identification, definition and characterization. Time varying gravity, Magnetic gradiometry.
  • Electrical Techniques Resistivity, field techniques, standard and Electrical Resistance Tomography, in the search for fluid targets, water, gas and pollution. Self Potential, Electroseismic and Electrokinetic signals and their significance in water investigations and fluid flow and leakage in dams and other structures. Induced and spontaneous polarization
  • Electromagnetic techniques: Ground Penetrating Radar both for indentifying structure and determining physical properties , Electromagnetic techniques and Nuclear Magnetic Resonance techniques in Hydrogeophysics and Pollution as reconnaissance Tools. Controlled Source Magneto-Tellurics and other electromagnetic methods as more sophisticated techniques for specialist applications
  • Seismic Techniques: Field data collection and a brief guide to reduction and interpretation. Shallow 2D and 3D seismic reflection and refraction for structure with noise-based microtremors and shear-wave techniques for engineering properties. Microseismic monitoring and acoustic emission in mines, slope stability and landslides, hydrofracturing and other applications
  • Joint Inversion and Modelling: How do we improve the definition/resolution of already high-resolution techniques? Discussion of combined inversion of complementary techniques which utilize different geophysics fields.

Borehole Geophysics: In order to better resolve targets especially in areas where reconnaissance geophysics has indicated useful targets may exist, we need to emphasize the use of well chosen borehole techniques using both drilled borehole and push techniques. These include Borehole radar, Self-potential and electrical resistivity as well as, of course, cross-hole seismic tomography

 

Participants' profile

Geoscientists, Environmentalists, Water, Civil and Geotechnical Engineers, Engineering, Mining and Hydro Geologists. In fact all those who have responsibilities for specifying and procuring geophysical services or appointing and directing geophysical staff but who do not feel that they understand the techniques, approaches, strengths and limitations of geophysics well enough to obtain optimal advice and understand the survey/interpretation information. The course will also be suitable for those who wish for an application/case-study-oriented introduction to Environmental Geophysics concentrating on the problems and their solutions with recourse to mathematical analysis only where really necessary.

 

Prerequisites

Attendees should have experience/knowledge of the types and range of environmental/engineering problems that are encountered in the near-surface and a desire to learn how to best approach them. A working knowledge of elementary mathematics and physics will help but a willingness to engage with the material is more important.

 

About the instructor

Peter StylesProfessor Peter Styles has taught Environmental and Engineering Geophysics for 35 years to undergraduates, postgraduates and professional training courses, nationally and internationally. He graduated from Wadham College, Oxford in Physics and a PhD in Geophysics at Newcastle-upon-Tyne. In 1977, he was appointed as Lecturer in Geophysics at University College, Swansea where he utilised mining-induced earthquakes to predict catastrophic failures in coal mines and developed the nascent microgravity technique into a robust tool for the detection of abandoned mineshafts and karst caverns worldwide. This developed into his lifetime interest in environmental geophysics. With postgraduates, he trialled the deployment of many other techniques including Induced Polarisation, Self Potential, Resistivity imaging and Magnetics for mineshaft detection and characterizing contaminated land. In 1987 he moved as Senior Lecturer in Geophysics to the University of Liverpool and as a Senior Visiting Scientist carried out extensive collaborative mining microseismological research with CSIRO in Brisbane, Australia and on microgravity for the detection of abandoned underground gold workings at Kalgoorlie, WA. He also has interests in low-frequency vibrations and noise (Infrasound) with emphasis on the effects of Wind Turbine Vibration on the UK Capability to discriminate nuclear weapons tests for the Comprehensive Test Ban Treaty Organisation seismic station at Eskdalemuir in southern Scotland. In 2000 he moved to Keele University as Professor of Applied and Environmental Geophysics where he was Head of the School of Earth Sciences and Geography and Director of the Environment, Physical Sciences and Applied Mathematics Research Institute. He has published more than 90 papers and many professional reports and obtained external research funding of more than 5 million pounds. The Applied and Environmental Geophysics Group which he founded has expanded greatly to take in Forensic Geophysics and Hydrogeophysics together with Clean Coal Bed and CCS monitoring techniques and his postgraduates have now populated and spawned many successful geophysical consultancies. He served as Honorary Secretary of the Geological Society of London from 1996 to 2000 when the Continuing Professional Development programme and accreditation of Geology Degrees were instituted. He served on the Board of the European Federation of Geologists and the Editorial Board of the Quarterly Journal of Engineering Geology and Hydrogeology. He was appointed President of the Geological Society of London and President of the British Association for the Advancement of Science (Geology Section) for 2007.He is a member of EAGE, SEG, AGU and PESGB. He is a Fellow of the Geological Society, the Royal Astronomical Society and the Institute of Materials, Minerals and Mining. From 2002 to 2010 he served as a Board Member of the British Geological Survey. He Chaired the UK Government Committee which developed Sub-Surface Exclusion Criteria for Geological Disposal of Radioactive Waste He is a member of the Royal Society Committee on Non-Proliferation of Nuclear Weapons and the Geosphere Characterization Panel of the Nuclear Decommissioning Authority.