Industry

Title : A new magnetic tensor approach to mapping magnetic rock properties and cover depth using AI

Date : 12th of November, Drinks and food from 4:30 for a 5pm start.

Presenter : David Pratt, Manager Research & Development, Tensor Research.

Location : Geoscience Australia, Scrivener Room.

Abstract

The presentation covers the use of an expert system AI method applied to magnetic gradient tensor data for mapping depth of cover and formation properties as a constrained 3D geological problem. The constraint takes advantage of an often, overlooked fact that the basement unconformity surface dominates the magnetic response measured in conventional airborne magnetic surveys. This dominance allows us to recover the rock properties and depth of the formations that are truncated by the basement unconformity. Recovery of rock property information from airborne surveys gives us the opportunity to look at old data with new eyes for the stones that were never turned.

Exploration under cover is very important to the discovery of new resources to replace existing mines as old resources are depleted. The magnetic method has evolved into an important tool for understanding the subsurface geology and location of favourable environments suitable for the emplacement of a broad range of economic minerals. A large part of the value is derived from qualitative interpretation of the spatial relationships and mapping of the inferred geology. However, much valuable information about the rock properties and cover depth is never recovered from the survey data.

Advances in the understanding of geologically constrained processing of the survey data along with rapid improvements in data quality and reduced line spacing promises to deliver higher resolution information on magnetic properties. Improved estimation of magnetic susceptibility provides guidance on the possible range of rock types associated with individual magnetic anomalies.

Magnetic remanence, often considered as inconvenient for interpretation, is an important indicator of a geological event, which in some cases may be associated with a mineralising process. We can now recover subtle magnetisation information indicative of magnetic remanence that is essentially invisible in a magnetic image. In many cases, subtle remanence events are lost in the low contrast blue areas of an image, yet these may contain clues to mineralising events.

About the speaker:

Manager Research & Development, Tensor Research. He holds a B.Sc. (Hons) and M.Sc. from the University of Sydney in Geology and Geophysics and a Ph.D. in Physics from the University of Newcastle. His early career started with the NSW Geological Survey, and then he worked as a geophysical consultant until 1984 when he co-founded Encom Technology. He was Managing Director from 2001 until it was acquired by Pitney Bowes Software in 2007. In 2010 he started Tensor Research with two colleagues to focus on advanced potential field research. He received the ASEG’s Grahame Sands Award in 2010 and Laric Hawkins Award in 2013.

Seminar Overview

The AusIMM Tasmania Branch, GSA, IAG and Tasmanian Government are pleased to bring you the Geoscience Forum.

The purpose of this forum is to assemble Geoscientists in one pleasant place to share their progress in exploration, mining and research.

This event is for sharing results and ideas in the geosciences and learning more about geology, in particular the geology of Tasmania.

Field Trip Friday, 6 December 2019

A field trip is planned the day after the Forum to visit historic and geological sites of interest in north east Tasmania.

Further details will be available shortly.

Accommodation

Delegates will need to book their own accommodation with the venue (Tidal Waters Resort) or at a venue of their choice.

Expressions of Interest for Guest Speakers

Please contact the Tasmanian Branch if you have any suggestions for speakers.

Sponsorship Opportunities

We welcome sponsors to assist in this event. Display tables will be available at the venue.

Contact the Tasmanian Branch to become a sponsor.

Registration details available here: https://ausimm.com/news/registrations-now-open-tasmania-branch-geoscienc...

AGS Tasmania Radar Interferometry Workshop

Registrations now open: AGS Workshop on INSAR and its Applications for Understanding Ground Movement

Radar interferometry (InSAR) is a rapidly expanding technique that offers valuable insight into ground deformation for a range of applications, particularly in the field of geotechnics. Due to advancing radar technology and increasing numbers of satellites, the quality and frequency of spaceborne radar coverage available for InSAR is continually improving. An increasing range of radar datasets are becoming freely available, further increasing application potential in geotechnical studies of various scale. However, InSAR is a technically complex technology necessitating appropriate planning, processing, and interpretation. This workshop is aimed at providing end-users and those commissioning imagery a basic understanding of the technique and its limitations in order to improve success and avoid disappointment. Those interested in conducting their own processing using commercially available software require further theoretical and applied background that is beyond the scope of this workshop.

Presenters

Dr. Bernhard Rabus is a Professor in the School of Engineering Science, Simon Fraser University, Canada. He has a geophysics background and is an internationally recognised expert in InSAR technology and processing with numerous academic publications to his credit, plus prior experience in government and industry roles. He teaches graduate and undergraduate courses in synthetic aperture radar applications, including InSAR, and undertakes a range of radar-based research activities.

Dr. Nicholas Roberts is a natural hazards geologist in the Geological Survey Branch of Mineral Resources Tasmania. He has strong interests in landslides and Quaternary geology with a range of academic publications and previous industry and government roles. Nick is also an Adjunct Professor at Simon Fraser University and collaborates with Dr. Rabus as an end-user to apply InSAR to a range of geological applications in diverse settings, including Tasmania.

Registration now open

An expressions of interest process earlier this year indicated strong support for the workshop to the point that the course is theoretically at capacity. Registrations are now open with priority given to those who previously responded if they register within 1 month of this notice being issued. Others are welcome to apply immediately should any spaces be available once the priority period is finished.

Day 1 (12 February) – The basics:

Providing high-level understanding of InSAR and its applications for a range of ground deformation questions through key lecture topics. The session will be held in central Hobart starting at 8:30

Basic introduction to synthetic aperture radar and its differences from remote sensing techniques conventionally used in geotechnical investigations (e.g. aerial photography, optical satellite imagery, LiDAR).

Overview of various InSAR techniques, their processing chains, and their strengths and weaknesses for particular applications.

Case studies of InSAR applications for slope stability and ground subsidence including discussion of specific considerations relevant to particular project types (e.g. pit mine stability, ground subsidence, landslide mapping, urban geohazards).

Merits of outsourcing and in-house processing (e.g. what to ask for when commissioning third party providers; assessing tenders from third party providers; what skill sets and resources are required for in-house processing; what data formats to specify from your provider).

Analysing and integrating InSAR data with other spatial data sets in a GIS environment (interested parties can bring laptops with Google Earth and QGIS installed and do some basic hands-on exercises).

Day 2 (13 February) – One-day field exercise:

Relating features in the field with their representation in InSAR datasets and building on the understanding of InSAR’s utility for addressing geotechnical questions in various environments.

Field sites will include locations for which various radar data and, where possible, InSAR results are available.

Please note that the field exercise will involve short walks over uneven ground to various sites. You are strongly advised to bring warm clothing.

Day 3 (14 February) – Technicalities of InSAR:

Providing greater detail on the processing chain for various InSAR techniques as well as specifics of data selection and access.

This final, lecture-based component of the workshop targets more advanced users including those with interest in conducting their own InSAR processing. Activities and topics will include:

Defining geotechnical problems in a way your InSAR provider will understand.

Selecting suitable imagery and satellites in greater detail.

Processing methods in more detail.

Advanced quality assessment of delivered products.

Registration fees

Standard Member rates*

Day 1 – The basics of InSAR $AUD700

Day 2 – Field Exercise $AUD500

Day 3 – Technicalities of InSAR $AUD500

Note: a $250 loading on the total fee applies to those who are not AGS members

Members of the NZ Geotechnical Society will qualify for AGS member rates

Student discount negotiable on application.

For all questions regarding registration and payments please contact the Secretary. For all technical questions please contact Colin Mazengarb at colin.mazengarb@stategrowth.tas.gov.au

See details at AGS’s website ( https://australiangeomechanics.org/courses/ags-tasmania-radar-interferom...) for registration. 

It is with great pleasure that I invite you to the 2019 Industry Sponsors Night on Thursday 14th November at the Coopers Alehouse. We will have presentations from some of our valued sponsors. This is a fantastic opportunity to hear about some of the projects our sponsors have undertaken over the previous year, and what they might have in store. See the image below for details.

Location: Coopers Alehouse, 316 Pulteney St, Adelaide

Time: 5:30 pm for a 6:15 pm start

Cost: Members and students free, non-members $10, includes finger food and drinks.

Please also save the date for our annual Honours Night and Christmas Party. The event will be on the evening of Thursday 12th December with more details to follow shortly, but will include talks from geophysics honours students with ample networking and socialising opportunity, and as usual free for Members and students, non-members are $10.

I hope to see you at these events, and please feel free to circulate to anyone who may be interested. Please contact me with any questions at sa-ntpresident@aseg.org.au

The 19^th  International Symposium on Deep Seismic Profiling of the Continents and their Margins - SEISMIX 2020

http://seismix2020.org.au/

On behalf of Curtin University, Perth, we would like to invite you to participate in the 19^th edition of the biennial International Symposium on Deep Seismic Profiling of the Continents and their Margins (SEISMIX 2020) that is now also extended to include the latest technological and scientific developments in the application of seismic methods. This high profile conference has been held in many countries it is our pleasure to welcome delegates to Fremantle W.A.

The Symposium will be held at the Esplanade Hotel in Fremantle, near Perth, Western Australia, from Sunday 15^th of March to Friday 19^th of March 2020.

A field trip is also planned to take place after the Symposium. It will run for seven to eight days and take in a wide range of Western Australia’s pristine coastlines and interior.

Symposium registrations and abstract submissions are now open:

1. Register here for the Symposium
2. Submit your abstract here

Date = Wednesday 13 November

Time = 530 to 7pm

Venue = Celtic Club, West Perth WA

Title = PSDM in relatively benign on-shore settings

Speaker = Marianne Rauch, TGS

Abstract:

Off-shore, depth imaging has been performed for a long time, especially to improve imaging around salt domes and faults. However, conventional wisdom dictates that in geological benign areas, it is not necessary to pre-stack depth migrate the data and stretching from time to depth is enough. A majority of the unconventional reservoirs are in geological less complex areas and this argument could be valid. We are presenting our thoughts why this is not correct and why applying a well-executed PSDM is worth the effort.

In many on-shore unconventional basins worldwide, the general geology around the tight reservoirs is nearly flat but the velocity and anisotropy within these layers can change rapidly laterally. PSTM velocities are based on hyperbolic assumptions and the ability to accurately image these changes are limited. In addition, it is crucial to solve the velocities in the near surface for accurate ray tracing but nearly impossible to do in the time domain. These issues can produce incorrect depthing and lateral positioning of the seismic events. A well-performed PSDM will result in an amplitude preserved dataset that has a higher resolution and can be used for geo-steering and attribute calculation which will further enhance the knowledge of the reservoir space. 

Speaker Bio:

Marianne received her PhD in Physics in 1985 from Uni Graz in Austria. She started her oil career as research assistant at Curtin University in Perth, Australia 30 years ago and has been active in geophysics ever since then. Marianne lived in many places and worked on-shore and off-shore basins all over the world. Her main specialties are DHI, seismic processing, depth migration, potential fields and researching new technologies, methodologies. She likes to do applied research, mentor and teach and is a seasoned presenter at conventions and workshop. She has published a good number of articles on several subjects and still is passionate about geoscience and the thrill to get more and unique information out of geophysical measurements that help drilling more successful wells. Currently, she is the Principal Technical Advisor, multi-client, onshore, TGS, Houston.

Dear ASEG Tasmania members and potential members,

Come and hear about Anton Rada’s work at the forefront of the development and implementation of drones for magnetic surveys.  Noon in the CODES Conference Room (UTas Sandy Bay campus), Wednesday 16th October.   Please let branch president Mark Duffett or branch secretary Matt Cracknell know if you’d like to join the speaker and Mark Duffett for lunch at the Uni Staff Club after the talk.

Dr Mark McLean, Geological Survey of Victoria presents a talk titled A new Full Spectrum FALCONⓇ airborne gravity and aeromagnetic survey over the Otway Basin, Victoria.

Tickets here

Our next meeting will be a joint event with the Young Professional Group and will happen on the 1st of October 2019. As usual it will be held at the Kelvin Club from 6 pm onward.

We will have the pleasure to welcome Dr Mark McLean from the Geological Survey of Victoria with a presentation about the Falcon survey that was acquired recently in the Otway Basin.

Please register before the 30/09/2019 noon time using the Eventbrite link.

In case of dietary requirement please email directly to vicpresident@aseg.org.au.

Abstract

Seismic surveying has been demonstrated to be the most effective technique to image sub-surface geological structure, particularly within sedimentary basins characterised by sub-horizontal stratigraphy where seismic energy is readily reflected back to the surface. However, there are some examples where seismic acquisition does not provide the most effective results: 1) where the area of interest lies along the coastal transition zone making acquisition problematic, 2) where there are sub-vertical geological structures (such as faults) which cause the seismic energy to be reflected away from the sensors and 3) where volcanic rocks attenuate the seismic signal.

Airborne Gravity Gradiometry (AGG) is a technique which measures very small changes in Earth’s acceleration. This approach is appropriate for the Otway Basin particularly in the transition zone where the geology is poorly understood. Qualitative interpretations can be made in map view, but data can also be quantitatively modelled using forward and inversion modelling processes. This approach makes airborne gravity gradiometry a complementary dataset for most of the seismic in the Otway which is dominated by 2D lines. Therefore, airborne methods provide an opportunity to not only ‘fill in the gap’ along the coast between seismic data collected off-shore and onshore, but there is also potential to add further detail to horizon geometries in between the more widely spaced (3-4km) seismic lines.

A new airborne Full Spectrum Gravity and magnetic survey has been undertaken as part of the Victorian Gas Program (VGP) using CGG’s FALCON® airborne data acquisition system. Flying commenced in August 2018 and was completed by early January 2019 (12 weeks). A total of 31042 line km of gravity, gravity gradiometry (Full Spectrum), magnetic and laser scanner data were acquired along 500 m spaced lines in a NW-SE orientation and 15000 m perpendicular tie lines. The surveyed region includes approximately 16000 km2 of the Otway Basin in Victoria, stretching from the edge of the Otway Ranges to the South Australian border, and from south of the Grampians to approximately 18 km offshore. Data were acquired at an altitude of 150 metres, increasing to 300 metres over built-up areas. A single engine Cessna Grand Caravan 208B was used to conduct the onshore portion of the survey and a DHC-6-100 (Twin Otter) aircraft was used for the offshore component. The survey has resulted in the largest airborne gravity dataset ever collected in Victoria and provides superior quality gravity imagery, compared with pre-existing data.

This presentation will visit a range of topics including the initial rationale for the survey, survey design, instrumentation and acquisition, but some emphasis will be placed on the new Full Spectrum product now being offered by CGG. This survey is the first publicly available Full Spectrum Falcon survey and is intended to capture the full spectrum of wavelengths by conforming the short wavelengths from the gravity gradiometry, with the longer wavelengths obtained from concurrently acquired conventional gravity.

Bio

Mark completed Arts/Science and Master of Science degrees at Monash University and then completed a PhD at The University of Melbourne in 2008 which involved acquisition, interpretation and modelling of an airborne geophysical survey over the Lambert Rift region in East Antarctica. Since then, Mark has worked at the Geological Survey of Victoria building regional 3D framework and rock property models using geological and geophysical datasets. Mark's time is now split between the GSV, and The University of Melbourne where he lectures in Applied Geophysics.

The talk can also be streamed to other members, if interested please contact one of the NT Division committee members.

Title: Synchronous natural climate cycles of the Common Era, for Europe, China and globally – existence and implications for future temperature trends

Author: Professor Michael Asten, School of Earth Atmosphere and Environment, Monash University. The talk summarises a joint effort with Kuan-Hui Elaine Lin (Univ of Taiwan) Carl Otto Weiss (PTB Braunschweig, Germany) Nicola Scafetta (Univ of Naples, Italy) and Alison Kelsey (U Qld), developed over three years at EGU 2017, 2018 and 2019.

Bio: Michael Asten is a Professor (retired) and ongoing Adjunct Senior Research Fellow in the School of Earth Atmosphere and Environment, Monash University, Melbourne.  He is a past-President of the ASEG, and served a recent three-year term as the AGC representative on the Australian Academy of Sciences UNCOVER Committee.  He has published 190 scientific papers.  He has developed passive seismic (microtremor) methods for 15 years, developing applications for earthquake hazard, and regolith characterization.   In the past six years he has applied signal processing methods to paleoclimate data sets with a view to quantifying past climate cycles and equilibrium climate sensitivity

Abstract:

We compare proxy temperature cycles contained in   data sets from European glaciation, China agricultural records, and two global proxy constructions.  A high correlation between European and China data sets, especially for 800-2000 CE, demonstrates a level of synchronicity beyond possible regional phenomena.  Spectral analysis shows a series of spectral peaks in all data sets consistent with those detected globally in cosmic ray flux, which supports the theory of natural climate cycles being partially under astronomical control. An interesting sidelight from the European and China data is observed temporal coincidence of social phenomena such as population decrease, starvation, disease and wars during phases of cooling, compared with human advancement during historical warmer phases. When the observed natural cycles are built into climate models, part of the global temperature increase of the past 170 years may be accounted for by natural cycles; we explore how this may influence estimates of climate sensitivity (the warming attributable to CO₂ forcing for a doubling of atmospheric CO₂).

Please don't hesitate to contact one of the NT Division committee members should you have any questions or wish to remote in for either presentation.

The talk can also be streamed to other members, if interested please contact one of the NT Division committee members.

Title: Comparisons of large igneous provinces (LIPs) and black shales in North China and Northern Australian cratons: Implications for paleogeographic reconstruction, paleoenvironment and subdivision of the geological time scale

Author: Prof Zhang Shuanhong, Institute of Geomechanics, Chinese Academy of Geology

Bio: Shuan-Hong Zhang is a Professor of the Institute of Geomechanics, Chinese Academy of Geological Sciences and vice-director of Key Laboratory of Paleomagnetism and Tectonic Reconstruction, Ministry of Natural Resources in Beijing. His recent researches mainly focus on Meso-Neoproterozoic tectonics and paleogeographic reconstructions of the Nuna (Columbia) and Rodinia supercontinents using large igneous provinces (LIPs) and rifting sediments, as well as the potential environmental effect of LIPs during the Meso-Neoproterozoic period. During last 5 years, he has published over 12 scientific papers in international journals such as Geology, Earth and Planetary Science Letters, Earth-Science Reviews, Precambrian Research, Tectonics, etc., and obtained two key research funds from the National Natural Science Foundation of China to study the Meso-Neoproterozoic tectonics and correlations of the LIPs and black shales during the "Boring Billon (1800 to 800 Ma).

Please don't hesitate to contact one of the NT Division committee members should you have any questions or wish to remote in for either presentation.