KEGS/BCGS Roundup Breakfast – Tuesday, January 24, 2017

SPEAKER: Dr. Martyn Unsworth, Professor of Geophysics, University of Alberta

TITLE: A geophysical view of mountain building: perspectives from the Andes, Himalaya and Antarctica

DATE/TIME: Tuesday, January 24, 2017

LOCATION: Fairmont Waterfront Hotel, Princess Louisa Room, Vancouver

REGISTRATION: Online at www.kegsonline.org (Deadline Jan 20, 2017)

ABSTRACT:

Geophysical imaging has proven to be a valuable tool in understanding the geological processes that occur within plate boundaries. Magnetotelluric (MT) exploration is especially useful in these studies since it can measure electrical resistivity, a rock parameter which is sensitive to the presence of fluids such as water or partial melt. In this presentation I will describe how MT has been used to study mountain building. In subduction zones, MT has defined the pathways taken by molten rock from the mantle to the surface where it is erupted by volcanoes. It has also detected some of the largest magma bodies on Earth and shown that the melt can have a high water content. The Himalaya and Tibetan Plateau were formed by the collision of the Indian and Asian plates and MT studies have imaged regions of molten rock that are sufficiently weak to flow. A final example will focus on Mount Erebus in Antarctica, where MT data are being used to image the magma system of a volcano which is not located on a plate boundary.

BCGS Technical Talk – December 15, 2016

Speaker: Gary Tipper, Skytem

Title: New generation of helicopter time domain electromagnetic systems for mineral exploration in rough terrain

Date/Time: Thursday December 15, 2016 @ 4:30pm

Location: 4th Floor Conference Room, Room 451, 409 Granville St. (UK Building at Granville and Hastings), Vancouver

Abstract:
Advances in technology for helicopter borne Time Domain Electro-Magnetic survey systems in the last 10 years has allowed the Mining industry the ability to acquire high resolution data in areas historically very difficult to access.

This presentation will focus on some of the past and ongoing technical challenges associated with survey design, drape mode versus contour mode flying, helicopter and pilot performance, technical limitations of past helicopter AEM systems and data quality issues of previous public domain BC AEM surveys.

It will show examples of past system geometry and design, claimed system dipole moments and calculations of Effective Dipole Moments (EDM), based on the wave forms of the different commercial AEM systems, and realistic depth of investigation.

It concludes with details of the new SkyTEM AEM systems for providing high resolution data in these challenging areas and recent case study of a new generation system flying in British Columbia.

BCGS Technical Talk – November 16, 2016

Speaker: Justin Granek, PhD Candidate, UBC-GIF, Vancouver, BC

Title: Application of Machine Learning Algorithms to Mineral Prospecting Mapping

Date/Time: Wednesday, November 16, 2016 @ 4:30 pm

Location: 4th Floor Conference Room, Room 451, 409 Granville St. (UK Building at Granville and Hastings), Vancouver

Abstract:

In the modern era of diminishing returns on fixed exploration budgets, challenging targets, and ever-increasing numbers of multi-parameter datasets, proper management and integration of available data is a crucial component of any mineral exploration program. Machine learning algorithms have successfully been used for years by the technology sector to accomplish just this task on their databases, and recent developments aim at appropriating these successes to the field of mineral exploration. Framing the exploration task as a supervised learning problem, the geological, geochemical and geophysical information can be used as training data, and known mineral occurrences can be used as training labels. The goal is to parameterize the complex relationships between the data and the labels such that mineral potential can be estimated in under-explored regions using available geoscience data.

Numerous models and algorithms have been attempted for mineral prospectivity mapping in the past, and in this thesis we propose two new approaches. The first is a modified support vector machine algorithm which incorporates uncertainties on both the data and the labels. Due to the nature of geoscience data and the characteristics of the mineral prospectivity mapping problem, uncertainties are known to be very important. The algorithm is demonstrated on a synthetic dataset to highlight this importance, and then used to generate a prospectivity map for copper-gold porphyry targets in central British Columbia using the QUEST dataset as a case study.

The second approach, convolutional neural networks, was selected due to its inherent sensitivity to spatial patterns. Though neural networks have been used for mineral prospectivity mapping, convolutional neural nets have yet to be applied to the problem. Having gained extreme popularity in the computer vision field for tasks involving image segmentation, identification and anomaly detection, the algorithm is ideally suited to handle the mineral prospectivity mapping problem. A CNN code is developed in Julia, then tested on a synthetic example to illustrate its effectiveness at identifying coincident structures in a multi-modal dataset. Finally, a subset of the QUEST dataset is used to generate a prospectivity map using CNNs.

The BCGS Executive is pleased to announce the speakers for the fall 2016 symposium.

Geophysics & Geological Case Studies

Geophysics plays and ever increasing role in geological investigations of the earth for resource exploration, extraction and other engineering applications (e.g. geological hazards). In this year’s Fall Symposium series from the BC Geophysical Society, we have brought together a wide range of different geophysical methods applied to an even wider array of geological investigations. In a one-day symposium, at a convenient downtown Vancouver location, for a very modest cost, come and learn about the latest geophysical technologies applied to some familiar and unfamiliar geological themes. The cross application of these techniques should lead to some thought provoking and interesting discussions throughout the day.

Sponsors:

Speakers:

Craig Miller, SFU, Physical Volcanology Group – Internal Structure and Volcanic Hazard potential of Mt Tongariro, NZ, from 3D Gravity and Magnetic Models

David Bingham, Bingham Geoscience – Geophysics on Fission’s Patterson Lake South Uranium Deposit.

Dikun Yang, Doug Oldenburg, UBC, Geophysical Inversion Facility – Reconciliation of airborne frequency-domain and time-domain data using an agree-to-disagree strategy in inversion:  groundwater case study.

Jonathan Rudd, Dias Geophysical – The value of 3D Resistivity surveying in a tailings management application

Ken Witherly, Condor North Consulting – Examples of ZTEM EM/mag over the Kemess (BC) and Resolution (AZ) Porphyry Copper Deposits.

Maxim Boisvert, Canadian Royalties and Dennis Woods, Discovery Int’l Geophysics – TDEM Exploration for Magmatic Ni-Cu-PGE Sulphide Deposits: A systematic strategy paying dividends in Nunavik.

Nick Williams, HPX – Advanced gravity and magnetic inversion methods: Platreef PGE-Ni-Cu resource.

Norm Cooper, Mustagh Resources – How to Plan Your Second 3D Program in Your Project Area.

Peter Fullagar, Fullagar Geophysics – Remanent magnetization inversion at the Cannington Mine, Queensland, Australia.

Peter Kowalczyk, Ocean Floor Geophysics – CSEM for gas hydrate exploration – a new approach using the Scripps Institute of Oceanography CSEM Vulcan system.

Scott Napier, Mira Geoscience – 3D inversion modelling of Sub-Audio Magnetic (SAM) data: An example from an orogenic gold deposit in the Yamarna Greenstone Belt, Western Australia.

Seogi Kang, Sarah Devriese, Dominique Fournier, Doug Oldenburg, UBC, Geophysical Inversion Facility – Inversion of airborne geophysics over the Tli Kwi Cho Kimberlite Complex.

Syd Visser, SJ Geophysics – Advancement of the Ootsa Project through Geophysical Innovation: Contributions of 3DIP survey.

Thomas Wade, Geotech – Integrated Helicopter ZTEM Electromagnetic, Airborne gravity and Aeromagnetic System Results over the Vredefort Dome Structure, South Africa.

The BCGS Executive is pleased to announce that registration is now open for the fall 2016 symposium, titled “Geophysics & Geological Case Studies”.

When: Friday October 14, 2016

Where: BCIT Downtown Campus (555 Seymour St. Vancouver, BC)

Time: 8:00 am – 5:00 pm (PST)

Cost: Regular $120 / Student $30

Please register in advance of the workshop. Your registration can only be guaranteed once payment has been received. The attendee name must be entered for registration to be complete.

Payment will be accepted through PayPal. Click on the “Buy Now” button below.