The document discusses uranium deposits in the Frome Basin of South Australia. It describes the geological framework that led to the formation of the deposits, including the uplift of granite source rocks and weathering that released uranium. Groundwater transported the uranium into sedimentary basins where it was trapped by reducing conditions. Detailed seismic surveys and deposit mapping are used to develop criteria to identify additional deposits. Case studies of specific deposits like Beverley and Four Mile East illustrate the deposit characteristics that indicate feasibility for in-situ recovery of uranium.

1. IAEA
Technical Meeting on Origin of Sandstone Uranium Deposits: A Global Perspective
VIC, Vienna, May 29 - June 01, 2012
PERSISTENT SURVEILLANCE FOR
PIPELINE PROTECTION AND THREAT INTERDICTION
Sedimentary Uranium Deposits
in the Frome Basin, South Australia –
Metallogeny and Recognition Criteria
for Exploration
H. Maerten1,2, A. Marsland-Smith1, M. Haschke2, A. Huddleston1, B. Packer1
1
Heathgate Resources Pty. Ltd., Adelaide, Australia
2
UIT GmbH Dresden, Germany

2. Overview
• Introduction:
Sedimentary uranium in Frome Basin
• Metallogeny aspects:
– Source: geological framework/source-term
– Transport: primary groundwater vs. potential secondary flow
paths
– Trap: source/distribution of reductants, trap mechanisms in
heterogeneous aquifers and varying deposit types/ages
• Geophysical surveys:
– Focus: shallow seismic → structural-stratigraphic model
including regional fault structures and local discontinuities
• Towards recognition criteria
– Indications from structural-stratigraphic model
(→ sandstone bodies): status and outlook
– Deposit mapping and 3D modelling from delineation
programs (roll-front geometry, characteristics)
• Outlook:
Methodology to assess ISR feasibility/optimization
2

3. Location
3

4. Frome Embayment – World Class Uranium Province
4

5. Known Deposits
5 km EL3934
N
Pepegoona
Range Front 5km Pepegoona West
(deposits in Eyre/
Cretaceous Pannikan
formations)
ML6387
Main Beverley
Four Mile
Four Mile East
ML6321
Tewalina channels
West Channel (Namba)
Paralana
Hot Springs Beverley
Central
Channel
Beverley East
South
Channel Beverley
Deep South
Tabular/
paleochannel
(flat mineral
EL3935 bodies)
EL3666
5

6. Source and Mineralization Potential
g es
Ran
s
d er
l in
F
n
er
rth
No er
int
Pa
t.
M
Radiometrics
6

7. Frome Basin U Deposits – Systematic
Holocene Frome Basin [Ma] Age of host rock
Neo- Pleistocene Willawortina
Uranium deposition
Cenozoic
Formation
gene Pliocene 3
Namba 5.3
Miocene Formation ~16 Beverley
23
Oligocene Pepegoona 2
Paleo- Eyre Pep. West
Eocene Formation ~43 Pannikan
gene Four Mile East
Paleocene
65
Creta- Late 1
ceous Early
Bulldog Shale
Cadna-owie Formation Four Mile
Murta Formation ~110
Basement uplift followed
Algebuckina Sandstone West
Late
Mesocoic
145 Multiple
by deep weathering
Jurassic Middle stacks of
Paleo- roll-fronts
Early „Classical“
channels/ (dis-
roll-fronts
Late tabular continuous)
Triassic Middle
Early 251 Deposit type
7

8. Ultimate U Source and Mineralization Potential
Cosmogenic 10Be erosion rate Ultimate U source:
estimates suggest that Northern Flinders - geochronological
- geochemical
formed over 4 Ma (Quigley et al., 2007). - mass-balance
If granites contain >30 ppm U, then - sedimentologic
yearly erosion ~2,400 lbs U. arguments
Possible chemical
weathering of
U-rich granites
before uplift
er (preconditioning)
int
Pa
t.
M
>9 Blbs U eroded into Frome Basin in the past 4 Ma
8

9. Conceptual Geological Section: Beverley
Beverley
Alpha
Beta
Gamma
9

10. Four Mile Schematic
10

11. Transport
• Channelized flow of U-bearing groundwater from
weathering granite blocks into Frome Basin
– Meteoric → groundwater
– Sandstone layers/lenses and paleochannels
• Time-dependence of hydrogeological flow regime in
geological scale
– Active tectonics
– Stress system according to orientation of Flinders Ranges
and known faults
– Seismicity/seismic surveys → transpressive tectonic regime/
tectonic constraints
• Primary groundwater flow versus secondary flowpaths
– Role of faults
11

12. Trap: Single-fluid versus Two-fluid Models
• Single-fluid model
– In-situ reductants immobilize U in aquifer
– In-situ reductants from microbial, anaerobic decomposition
of organic matter
• Two-fluid model
– Upflow of reductants into aquifer from underlying organic-
rich formations, thus, immobilizing U from the groundwater
Jaireth et al., 2008
12

13. Reduction Processes – Organic Matter Decomposition under
Anaerobic Conditions (Schematic)
Fe-oxide reducing bacteria
Fe2+
FeOOH
Organic
material
Sulfate reducing bacteria
Acetate
Formate
H2S
H2
SO42-
CO2
Methanogenic bacteria
Fermenting
bacteria
CH4 + CO2
CH4 + H2O
Re-drawn from Appelo/Postma
13

14. Reference: Sediment REDOX – GA Study EL 5/6
GA18232
14

15. In-situ reductants or reductant
REDOX Mapping – EL 5/6 transport via faults?
Long transport
pathways from
source rock
to trapping
(Beverley within
Namba)
Short transport
pathways
(→ Range Front
Same patterns observed
deposits)
at Beverley/Four Mile
GA18232
15

16. Towards Recognition Criteria (Programmatic)
• Conventional geophysical surveying
– Including gravimetrics, magnetics, airborne electromagnetics,
induced polarization, magnetotellurics, and radiometrics
– From data it is hard/impossible to identify recognition criteria in
a regional scale
• New high-resolution seismic surveys (2D):
– Throughout Paralana Lease (Beverley) and in the Range Front area
(including Four Mile) – total of ~500 line km
– Targets: sandy formations (including paleachannels) and faults
• In progress:
– Improved migration procedures for higher resolution/ significance
– Joint inversion (seismic + CSAMT/gravimetrics)
– Advanced seismic analysis including attribute analysis and AVO
(towards rock physics)
• Outlook: 3D seismic surveying:
– Much better significance for (bending) channel structures
16

17. 3D Paralana Model with Beverley Deposit (2D Seismic)
Flinders Ranges
t
ul
Fa
na
ta
on
Po
Top
of:
Namba
Eyre
Bulldog Shale
Cadna-owie
Basement
17

18. 3D Paralana Model with Beverley Deposit (2D Seismic)
18

19. 3D Beverley (2D Seismic – Line 2500)
Beverley Central
19

20. 3D Beverley (2D Seismic Line 2500 + Drill Logs)
Beverley Central
sand channel
20

21. 3D Beverley (2D Seismic Line 2500 + Drill Logs + Ore)
Beverley Central
ore body
21

22. 3D Beverley (from 2D Seismic) + Ore Bodies
Top of Bulldog Shale Top of Eyre Formation
Line 2500 Beverley deposit
Poontana Fault
22

23. Range Front Deposit Example: Four Mile East
Top of:
Basement
23

24. Range Front Deposit Example: Four Mile East
View from Flinders Ranges into the Basin
Silcrete on top
of sand body in
Eyre Formation
(chemical
wheathering
during high-T
climate period)
Sandy
Eyre
Formation
Top of basement
Faults
24

25. Range Front Deposit Example: Four Mile East
View from Flinders Ranges into the Basin
Silcrete on top
of sand body in
Eyre Formation
(chemical
wheathering
during high-T
climate period
U mineralization
in Eyre
Formation
Top of basement
Faults
25

26. Ranges Front Stratigraphy (Example: Four Mile East)
Extending to Beverley North
26

27. Ranges Front Stratigraphy (Example: Four Mile East)
Max.
Boun-
thick- System
Strata ding
ness Lithofacies tracks
Age
surface
[m]
Alluvial fan-braided channel conglomerates with fine floodplain/
50
Willwortina Will lacustrine muds; several coarsening upwards cycles; incised base; Tectonic Pliocene
hematitic
Alluvial fan-fluvial conglomerates and sands/multiples fine upward Late
125
Namba Namb cycles; disrupted floodplain muds (‘injection flames’); highly incised Tectonic Oligocene –
+ aeolian contributions
base; kaolinitic Late Miocene
Fluvio-lacustrine; channel sands/conglomerates, fine-grained ‘glass’
Basin
Eyre 4/5 sands, thicker lucustrine muds with turbiditic sands, abundant mud Late HST
‘rip up’ clasts; minor lignitic debris
Multi-storey (amalgamated) braided channel sands/conglomerates;
Eyre 3 12 Early HST
floodplain muds; minor lignitic debris Early – Middle
Eyre
Meandering channel sands with minor conglomerates; floodplain Eocene
Lake Eyre (Frome Embayment)
Eyre 2 20 sands/silt/muds; abundant lignitic debris/some thin coals (zone of TST
maximum flooding/accomodation)
Multi-storey (amalgamated) braided channel sands/conglomerates;
Eyre 1 8 LST
minor lignitic debris; highly incised base
‘Bulldog shale facies’: carbonaceous shales/silts, fine sands and
Bull 4 5 TST Early Albian*
‘pebbly mudstone’; abundant bioturbation
Bull 3 0 Grain flow sands/turbidites (present at Four Mile West only) Late Aptian*
Bull 2 5 Sandy diamictite with dropstones Glacial *Microplanctonic
age extrapolated
from Four Mile
Bull 1 20 Basal conglomerates (clast-supported ‘cabblestones’) West
27

28. Rollfront Morphology at Four Mile East (Area 1)
UB
LB UB
LB
50m
Uranium deposition controlled by both
REDOX and (heterogeneous) permeability
within host formation (aquifer)
→ recognition criteria on local scale to follow up
rollfronts within drilling programs
Open pit (Texas)
28

29. Beverley North Roll Fronts – Morphology
29
29

30. Core Samples Four Mile East (Area 1)
30

31. Four Mile East Details – Area 1 (Upper Rollfront)
% of ore zone in pyrite (organic carbon – more scattered)
31

32. Four Mile East Details – Area 1 (Upper Rollfront)
Disequilibrium DEF – pU3O8/eU3O8 (U grade/γ activity)
32

33. Four Mile East Details – Area 1 (Upper Rollfront)
% of ore zone in clays
33

34. Four Mile East Details – Area 1 (Upper Rollfront)
Host formation flow rates
34

35. Conclusion: ISR Feasibility
• Data matrix for assessment on the basis of
– (Real) Uranium GT (grade/thickness)
– Permeability (flow rates)
– Mineralogy/geochemistry (in particular, abundance of
reductants including organics and pyrite)
• Reactive-transport model simulation of ISR performance
– Forecast of wellfield performance + experience
– Adjustment of ISR chemistry/optimization
→ To be presented at the IAEA Technical Meeting/
Consultants’ Meeting on ISL Technology, Nov 19-23, 2012
35