New Trends in ShallowGeophysical/Seismic Surveying
and Borehole Logging
Dr. Michael HaschkePrincipal Geologist
UIT GmbHZum Windkanal 2101109 Dresden-Germanyemail: [email protected]
www.uit-gmbh.de
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General AtomicsElectronic
SystemsInc
GeneralAtomics
General AtomicsAeronautical
SystemsInc
General AtomicsUranium
Resources
UIT is GA and Affiliates
UIT
General AtomicsEnergy Multiplier
Module EM2
GENERAL ATOMICSTechnologies Corporation
SpezialtechnikGroup
Germany
Our Exploration Targets: Shallow Mineral Resources
Uranium Roll Front in Open Pit Mine – South Texas
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UIT: R&D in Mineral Resource Exploration for GA
150 mGammaRLLDNeutronPFN
455 survey kmSeismic Survey 2010-2011
Frome Basin, South Australia200m depth
Innovative Geophysical Borehole Logging
Logging Operation
APFN+ operationin the field
On-site calibration pits(QA compliant)
Advanced Geophysical Borehole Logging
APFNBasic function
APFNPetrophysical features
APFN+
Mineralogical Logging
• Advanced PFN tomeasure U gradesaccurately(i.e. in-tool correctionfor influencing factorsnot considered by PFNtechnology)
• Neutron correlations• Extension of APFN for
- Porosity- Density- Macroscopic neutroncross section (clay)
- Lithology systematic- Permeability (calculated)
• -ray spectroscopy• Additional logging of
- Elemental concen-trations in formation
- Mineral abundances(quartz, pyrite, calcite,feldspar, clay minerals,optional organic carbon)
• Pulsed DT-neutron generator technology combined with multiple neutronand -ray detection channels (multi-scaling/spectroscopic)
– Universal logging technique to log ore grade, geophysical formationparameters (including permeability) and mineral abundances.
– Mapping of comprehensive deposit characteristics from logging ofdelineation drill holes for more reliable planning of ISR .
Geophysical APFN Parameters
0
10
20
30
40
50
5 15 25 35 45
matrix cross section ΣM [c.u.]
poro
sity
Φ [%
]
Breccia
Argillageoussandstone
Sandstone
Conglomerate
Silcrete-arenite/basement
Siltstone
Claystone
0
10
20
30
40
50
5 15 25 35 45
matrix cross section ΣM [c.u.]
poro
sity
Φ [%
]
PR1299 [258-279m]PR1301 [196-217m]PR1301 [230-162m]PR1302 [193-206m]PR1302 [239-275m]PR1304 [199-242m]PR1437 [187-213m]
…measures the attenuation of the thermal neutron flux [in capture units]
Mineral Resource Exploration @ UIT
200m depth
Gravel,coarse sand
Willawortina Fm.
Lacustrineclay & sand
channelsNamba Fm.
Fluvial sandEyre Fm.
Marine shaleBulldog Shale
GammaRLLDNeutronPFN
200 m
Seismic Imaging in the Frome Basin 2012
channel
Willawortina Willawortina
Beverley Clay
Seismic Exploration ApproachIdentify repeatable patterns in seismic reflection data:
- sand channels- concave dents in reflectors- porosity contrast
channel
Beverley Clay
Where to drill …?
200m
lower limb
upper limb
roll
reduced
protorenose
ROLL FRONT
300m depth
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A Highly Prospective Region – U in Palaeo Valleys
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Beverley Mine – ISR Technology
World’s most advanced In-Situ Recovery (ISR) mine
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Beverley Example of Channel Patterns
Data source: >12,000 drill logs Ore outline
500m
Alpha Mud Surface
1,000 mchannel amplitude
ca. 180 mchannel width
Radiometrics – DEM - Gravimetry
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2km(from Skirrow, 2009)
Digital Elevation Model
U ore
Uranium Band Radiometrics
U ore
Gravimetry with3D Fault Surfaces
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Uranium Mineralization
Laminations ofcoffinite-quartz-clay
Coffinite U(SiO4)1-x(OH)4x occurs as disseminationswithin interstitial clay (kaolinite-dominant).3D imaging (SEM)
Seismic Imaging in the Frome Basin 1984 - 2012
1984-SPG Petratherm 2006 Curtin U 2012 UIT/Petrologic
Central Line
2010/2011 Velseis
2500 2500Enhancedresolution
TIME
DEPT
H
TIME
DEPT
H
Central Line
Key to High-Resolution Shallow Seismic Imaging
2012 UIT/DMT Petrologic
2500Enhancedresolution
DEPT
H
Maximum resolution in shallow seismic exploration(<500m depth) requires a combination ofcustomized methods:
• Energy source: e.g. high-frequency 8.4t IVIEnvirovibe vibroseis buggies @ 60 kN peakforce
• Tight 2-5m shot intervals• 2-5m geophone recording intervals• Customized data processing
- Derive new deconvolution parameters• Redetermine new static
- Refraction static (instead of elevation static)
Impact of Petrophysics on Seismic Resolution
Outlook: 3D Seismic Surveying
From Kolla et al. (2007) and Posamentier et al. (2007)
deep-water sandchannel turbidite,Gulf of Mexico
amplitude stratalslice from Pliocene
sediment sequence,Natuna Basin,
offshore Indonesia
