3D Modeling for exploration

Size: px

Start display at page:

Download "3D Modeling for exploration"

Georgina Jefferson
5 years ago
Views:

1 3D Modeling for exploration Tero Niiranen Acting Division Manager Bedrock and Resources, GTK Rovaniemi office

Regional scale Drill core and bedrock observation data used, however, relies heavily on geophysical data (especially potential

2 3D modeling supporting exploration in GTK Visualizing data in 3D world 3D geophysical & geological models Target scale Drill core data, bedrock observation data, ground & airborne geophysics Resource modeling, delineating potential extensions for mineralization Regional scale Drill core and bedrock observation data used, however, relies heavily on geophysical data (especially potential fields and seismic data) Understanding the tectonic and geological processes, 3D extension of geological units and structures 2 km

Geological, geophysical and geochemical signatures of

3 D3 The Aims for 3D modeling Better understanding of: Ore forming processes Ore controlling structures, lithologies Geological, geophysical and geochemical signatures of mineral deposits Geological evolution...in space and time D

4 Modeling process Data collection & verification Geophysical data Bedrock obs, geol maps & drill core data Derivative maps (TDR, 1- VD), Worming 2D& 3D Structural interpretation 3D inversion modeling of potential fields data Iterative 3D Lithological modeling Products 3D geological and geophysical models Numerical modeling (paleostress, fluid flow etc)

Data processing: Upward continued gradient maximas Gravity data (bouguer

worms map & known gold deposits Automated edge detection method for

and structures and their extensions in depth Case CLGB: gravity worms

5 Data processing: Upward continued gradient maximas Gravity data (bouguer anomaly) Calculating upward continued gradient maximas or worms Resulting worms map & known gold deposits Automated edge detection method for potential fields data Fast processing, results delineate geological contacts and structures and their extensions in depth Case CLGB: gravity worms display spatial correlation with known epigenetic deposits (verified with WofE method)

6 3D forward modeling Iterative method for fitting 3D volumes with given properties to explain measured data Good results, however, only with tight co-operation with geophysicist and geologist Cons: Time consuming and laborous 3D forward model of the major lithological units of the CLGB based on the gravity data

fast tool allowing estimates of depth extension and orientation of geological features Plan view 1 km Oblique

7 3D inversion methods for potential fields data 3D inversion methods applied to potential fields data (mag & gravity) routinely in GTK Rovaniemi office Both unconstrained and constrained methods can be used Relatively fast tool allowing estimates of depth extension and orientation of geological features Plan view 1 km Oblique view fom south, susc. > Magnetic inversion model, block size 20x20x20 m Ground magnetic survey N

AMT Induction coils Receiver AMT is a geophysical electromagnetic

Uses thunderstorm activity (lightning) as electromagnetic source field.

8 AMT Induction coils Receiver AMT is a geophysical electromagnetic sounding technique for studying electrical conductivity structure of the earth. Significant depth extent. Survey depths from several hundred meters to several kilometers. Uses thunderstorm activity (lightning) as electromagnetic source field. 2D profiles & 3D grids GTK purchased AMT equipment in 2011 and has trained two field crews to operate them Electrodes

9 AMT-results AMT-measuring points on ground mag map High susceptibility High conductivity 2D inversion combined with seismic data 3D AMT inversion combined with 3D magnetic inversion

10 Methods in developement: 3D SOM maps AeroMag Bouguer 3D SOM model, 7 clusters

11 Future: 3D GIS prospectivity mapping 3D/4D mineral system modeling Paleostress modeling Fluid flow modeling Alteration systems

12 Clock is ticking any questions?

MPM Online Tool ArcSDM 5 Final Seminar May 4 th 2018, Rovaniemi

MPM Online Tool ArcSDM 5 Final Seminar May 4 th 2018, Rovaniemi http://gtkdata.gtk.fi/mpm/ ArcSDM 5 Final Seminar May 4 th 2018, Rovaniemi Funding 2 Vesa Nykänen/ArcSDM5 Seminar 4.5. 2018 http://gtkdata.gtk.fi/mpm/ 3 Vesa Nykänen/ArcSDM5 Seminar 4.5. 2018 http://gtkdata.gtk.fi/mpm/