New Trends in Shallow Geophysical/Seismic Surveying and Borehole Logging

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1 New Trends in Shallow Geophysical/Seismic Surveying and Borehole Logging Dr. Michael Haschke Principal Geologist UIT GmbH Zum Windkanal Dresden-Germany

2 UIT is GA and Affiliates GENERAL ATOMICS Technologies Corporation General Atomics General Atomics Aeronautical Systems Inc General Atomics Electronic Systems Inc General Atomics Energy Multiplier Module EM2 General Atomics Uranium Resources Spezialtechnik Group Germany UIT 2

3 Our Exploration Targets: Shallow Mineral Resources Uranium Roll Front in Open Pit Mine South Texas

4 UIT: R&D in Mineral Resource Exploration for GA Frome Basin, South Australia 200m depth Gamma RLLD Neutron PFN 150 m survey km Seismic Survey

5 Innovative Geophysical Borehole Logging

6 Logging Operation On-site calibration pits (QA compliant) APFN+ operation in the field

7 Advanced Geophysical Borehole Logging Pulsed DT-neutron generator technology combined with multiple neutron and -ray detection channels (multi-scaling/spectroscopic) Universal logging technique to log ore grade, geophysical formation parameters (including permeability) and mineral abundances. Mapping of comprehensive deposit characteristics from logging of delineation drill holes for more reliable planning of ISR. APFN Basic function Advanced PFN to measure U grades accurately (i.e. in-tool correction for influencing factors not considered by PFN technology) APFN Petrophysical features APFN+ Mineralogical Logging Neutron correlations Extension of APFN for -ray spectroscopy Additional logging of - Porosity - Density - Macroscopic neutron cross section (clay) - Lithology systematic - Permeability (calculated) - Elemental concentrations in formation - Mineral abundances (quartz, pyrite, calcite, feldspar, clay minerals, optional organic carbon)

8 Geophysical APFN Parameters 50 Breccia Siltstone 40 Sandstone 30 Argillageous sandstone 40 Claystone Conglomerate 20 porosity Φ [%] porosity Φ [%] 50 PR1299 [ m] PR1301 [ m] PR1301 [ m] PR1302 [ m] PR1302 [ m] PR1304 [ m] PR1437 [ m] Silcrete-arenite/basement matrix cross section ΣM [c.u.] measures the attenuation of the thermal neutron flux [in capture units] matrix cross section ΣM [c.u.] 45 45

9 Mineral Resource UIT Gravel, coarse sand Willawortina Fm. Lacustrine clay & sand channels Namba Fm. 200m depth Fluvial sand 200 m Gamma RLLD Neutron PFN Eyre Fm. Marine shale Bulldog Shale

10 Seismic Imaging in the Frome Basin 2012 Willawortina Willawortina Beverley Clay Beverley Clay channel channel Seismic Exploration Approach Identify repeatable patterns in seismic reflection data: - sand channels - concave dents in reflectors - porosity contrast

11 Where to drill? upper limb reduced roll nose protore ROLL FRONT lower limb 300m depth 200m

12 A Highly Prospective Region U in Palaeo Valleys 12

13 Beverley Mine ISR Technology World s most advanced In-Situ Recovery (ISR) mine 13

14 Beverley Example of Channel Patterns 500m ca. 180 m channel width 1,000 m channel amplitude Data source: >12,000 drill logs outline AlphaOre Mud Surface 14

15 Radiometrics DEM - Gravimetry 2km (from Skirrow, 2009) U ore U ore Uranium Band Radiometrics Digital Elevation Model 15 Gravimetry with 3D Fault Surfaces

16 Uranium Mineralization 3D imaging (SEM) Coffinite U(SiO4)1-x(OH)4x occurs as disseminations within interstitial clay (kaolinite-dominant). Laminations of coffinite-quartz-clay 16

17 Seismic Imaging in the Frome Basin Curtin U 2500 Enhanced resolution TIME DEPTH TIME 1984-SPG Petratherm 2500 Central Line DEPTH Central Line 2010/2011 Velseis 2012 UIT/Petrologic

18 Key to High-Resolution Shallow Seismic Imaging 2500 Enhanced resolution Energy source: e.g. high-frequency 8.4t IVI Envirovibe vibroseis 60 kn peakforce Tight 2-5m shot intervals 2-5m geophone recording intervals Customized data processing DEPTH Maximum resolution in shallow seismic exploration (<500m depth) requires a combination of customized methods: - Derive new deconvolution parameters Redetermine new static - Refraction static (instead of elevation static) 2012 UIT/DMT Petrologic

19 Impact of Petrophysics on Seismic Resolution

20 Outlook: 3D Seismic Surveying amplitude stratal slice from Pliocene sediment sequence, Natuna Basin, offshore Indonesia deep-water sand channel turbidite, Gulf of Mexico From Kolla et al. (2007) and Posamentier et al. (2007)