WA

ASEG WA September Tech Night
SEG/AAPG Distinguished Lecturer,
Steven Constable

Thursday 29 September 2016
5:30 pm for 6:00 pm
City West Function Centre, 45 Plaistowe Mews, West Perth WA 6005

Geophysical Inversion: Which Model Do You Want? 
With a broad suite of geophysical inversion tools now available, it is seductively easy to submit your data, turn the crank, and obtain a model. But is the model meaningful? Are the data properly fit? How much does the model depend on the data, and how much on parameters in the inversion code, such as model discretization and regularization penalty? The inversion process depends as much, if not more, on the error structure of the data and inversion parameters as the data themselves. We all know that geophysical inversion is non-unique, but many people are surprised just how different models can be that fit the data equally well. And what exactly constitutes an adequate fit to the data? Without a rigorous analysis of error structure, choice of misfit can be highly subjective. Some rely on “L-curves”, but it can be shown that they too are subjective and depend very much on the choice of plotting parameters. Seeking to drive misfit down as low as possible can also be perilous – the least squares best fitting models for some problems are known to be pathological, and it is likely that this is true in general. In this lecture I shall attempt to provide an understanding of the practical issues associated with geophysical inversion, and provide a road map for avoiding common pitfalls.

Steven Constable studied geology at the University of Western Australia, graduating with first class honors in 1979. In 1983 he received a Ph.D. in geophysics from the Australian National University for a thesis titled “Deep Resistivity Studies of the Australian Crust” and later that year took a postdoc position at the Scripps Institution of Oceanography, University of California San Diego, where he is currently Professor of Geophysics. Steven is interested in all aspects of electrical conductivity, and has made contributions to inverse theory, electrical properties of rocks, mantle conductivity, magnetic satellite induction studies, global lightning, and instrumentation. However, his main focus is marine electromagnetism; he played a significant role in the commercialization of marine EM for hydrocarbon exploration, work that was recognized by the G.W. Hohmann Award in 2003, the 2007 SEG Distinguished Achievement Award, and now the SEG 2016 Reginald Fessenden Award. He also received the R&D 100 Award in 2010, and the AGU Bullard Lecture in 2015. More recent efforts have involved the development of equipment to map gas hydrate and permafrost. Steven has served as an associate editor for the journal Geophysics, as a section secretary and corresponding editor for the American Geophysical Union, and on the MARELEC steering committee

Registrations close September 26

Target 2017

Target 2017: Innovating now for our future conference will be held at UniClub, University of Western Australia Uniclub from April 19-21 2017 in Perth, Western Australia.

The mining industry must act now in order to find the next generation of mineral deposits that will sustain human development. Most resources extracted from the Earth today exploit near-surface deposits discovered more than 30 years ago. The outcrop/subcrop search space is being rapidly depleted of world-class deposits, leaving broad volumes of the Earths’ crust unexplored. Innovation is required to aid discovery of new tier-one deposits, especially if the exploration space is to be truly broadened extending under cover. Innovation is also required to increase the discovery to investment ratio, which is at an all-time low. Target 2017 will focus on all aspects of mineral exploration and provide a unique opportunity to workshop solutions to the challenges that lie ahead.

We expect more than 250 attendees from around the Australian and international mineral exploration community, including executives, professionals, researchers and university students. The technical program will consist of a unique plenary session, panel discussions and poster sessions, focusing on multi-commodity exploration from greenfields at the regional scale through to brownfields and near mine exploration. Short courses and workshops will cover topics such as the mineral systems approach to exploration targeting, applied exploration geophysics and geochemistry and 3D exploration and will provide hands-on training opportunities for conference delegates.

Presented in Perth, Western Australia the conference will benefit from being organized in the Australian Capital for the mineral industry. Target 2017 will be an excellent opportunity to network with your peers in the collegial atmosphere that has developed between industry, government and academic professionals in the minerals industry.

We look forward to welcoming you to Target 2017 and together shaping tomorrow’s exploration strategies for the future sustainability of our industry.

Keynote speakers

• Cam McCuaig (BHP), Methods of targeting across all scales – what important elements to consider?
• Carl Brauhart (CSA Global), Computational modelling in mineral systems analysis – the OSNACA example
• Glen Masterman (Evolution Mining), Successful targeting and exploration success in the mining industry – a corporate perspective
• June Hill (CSIRO), The role of machine learning in brownfields exploration
• Nick Hayward (Teck), Exploration targeting – best practice
• Richard Ernst (Carleton University): Multi-Commodity, Multi-Scale Exploration Targeting Using the Large Igneous Province Record
• Rob Hough (CSIRO), Creating a new frontier in detection and data integration for exploration through cover
• Ross Cayley (GSV), Thinking and targeting on the lithospheric scale as part of an exploration strategy:  using pre-competitive data
• Alok Porwal (Indian Institute of Technology), Uncertainty mapping in GIS-based prospectivity modelling
• Sandra Occhipinti (CET), Methods of targeting across all scales: shat important elements to consider; learnings from the Capricorn Distal Footprints study

EARLY BIRD REGISTRATION CLOSES 28 FEBRUARY 2017