1. Geologic Setting of Interformational Braided
Channel Type Sandstone Uranium Deposits
in North China
M. Zhu, R. Wu, X. Liu, F. Nie, D. Yu
East China Institute of Technology
2012/05/29

2. 1. Basins and U Deposits in North China
2. General Characteristics of U bearing
Mesozoic to Cenozoic Basins
3. Geologic Setting of Interformational
Braided Channel Type Sandstone
Uranium Deposits －－ Examples
4. Conclusions

3. 1.Basins and U Deposits in North China
Songliao Basin
Turpan-Hami Basin
Yili Basin
Erlian Basin
Bayingebi Basin
Ordos Basin

4. 2. General Characteristics of U bearing Mesozoic to
Cenozoic Basins in North China
Area M.
Basin Epoc
Basin type Resource Deposits
Name 10 4 h
s
km 2
2.85 T-J Rift, depression, Coal+Oil+U 511, 512, 509
compression superposed
Tuha 5.35 C2-T-J Tensional-depressional Coal+Oil+U Shihongtan
piggyback basin
Bayinge- 12 Mz Strike slip-pull apart Oil+U Tamosu,
bi basin Celaomiao
Ordos 25 C-P-T Composite craton type Coal+Oil+U Dongsheng,
(Foreland basin) Dongwan
Erlian 10.9 J-K Tensional downfaulted- Coal+Oil+U Saihangaobi,
depressional type Bayanwula
Hailar 4.05 J-K Tensional downfaulted- Coal+Oil+U Kelulun,
depressional type Chagannor
Songliao 26 J3-K Tensional downfaulted- Coal+Oil+U Western slope
depressional type
Kailu 3.32 J3-K Tensional downfaulted- Coal+Oil+U Qianjiadian,

5. Uranium Mineralization Characteristics in Different Basins
Braided Braided Braided
channel channel channel
Roll/tabular

6. Sedimentation system of U ore-bearing formation
Yili Tuha Bayingebi Erlian Kailu
Lacus
Lacus/
Lacus/
Braided
Fluvial
Fluvial channel
Braided
Delta
Fan Braided
Delta Fan Braided
Delta Delta channel
front

7. 3. Interformational Braided
Channel Type Sandstone Uranium
Deposits
Examples: Ordos Basin
Erlian Basin

8. *about 300,000 km2
*A basin of energy resource
3.1 Ordos Basin coal, oil and nature gas
*A large-scale sandstone-type U in
Zhiluo Fm. of J2 in Dongsheng area,
northeastern part of the basin.

9. 3.1.1 Basin evolution
Downfaulted basin
Foreland basin
Depression basin
Foreland basin

10. J 1-2
Depression
basin
strata
column

11. 3.1.2 Unconformities in Jurassic
and between the J2 and K1
Unconformity between J2z and J2y --- tectonic reversion

12. High resolution seismic profile in North Ordos
(after Zhu, 2010)

13. The lower uncomformity (J2z/J2y) and
kaolinization in J2y (Yanan formation)
Dongsheng, North Ordos Basin
(Jiao, 2010)

14. 3.1.3 Sedimentation system and facies
K1 Alluvial fan depositional system
High sinuosity meandering river
Fluvial depositional system
Channel
Flood plain
J2z
Low sinuosity meandering river 河道沉积和
Channel 泛滥平原沉
积
Flood plain
River island U
Braided stream
Braided channel U
J2y Delta depositional system

15. Stratigraphic Column of Yan’an and Zhiluo Fms in Ordos
U
U

16. Zhiluo Fm (J2z)
High sinuosity meandering river
Low sinuosity meandering river
Braided stream

17. Facies of low sinuosity meandering river
Low sinuosity meandering river
U U U
Braided stream channel sedimentation

18. Section showing the sedimentation system
and facies in Dongsheng
Alluvial fan depositional system
High sinuosity meandering river
Low sinuosity of meandering river
Braided stream
Delta depositional system

19. The composite profiles of Dongsheng deposit

20. 3.1.4 Bleaching of red beds
Possible relations of
hydrocarbon to U
mineralization
Oil immersed sandstone

21. Asphalt vein and
U minerals in
Dongsheng
(BRIUG, 2004)

22. Concentration of Hydrocarbon in sandstone
and ores in Dongsheng
CH4 C2H6 C3H8 i-C4H10 n-C4H10 i-C5H12 n-C5H12 No
Normal 269.70 56.41 39.67 2.96 7.57 2.54 2.55 5
S.
Poor 346.59 77.64 33.13 4.04 7.89 3.18 3.29 3
ores
Rich 1189.5 218.48 117.30 8.91 18.93 6.50 5.88 2
ore
( Team No. 208, CNNC,2001)

23. 1 6-1 1 2-1 0 4-1 0 1-1 0 5- 1 Q11 50
50
Q
0
K2n
-50
5
K2y2
4
3
-100
2
K2y1 1
-150
0
K2qn
-200
F4 F3
0 200 400m
Geochemistry of gray and red sandstone in
Qianjiadian deposit in Kailu basin
U CH 4 Eh Fe 2 O3 C 有 机
Samples -6 pH S% CO 2%
( × 10 ) (μ g/kg) (mv) / FeO (%)
Gray S. 39 60.5 565.7 8.9 41.5 0.15 1.62 0.67 0.2
Red S. 15 2.1 147 9.6 17 0.02 1.30 5.26 0.01
Zhao, 2010

24. asphalt veins
Immersed oil
Immersed oil
Oil immersed features in various basins
A-Ordos ； B-Qianjiadian ； C/D-
Erlian
Migration Hydrocarbon ?

25. 3.1.5 New Exploration sections in Husiliang area
Wuligemiao Nalinguo Caidenghao
Hantaimiao
Dongsheng
(Team No. 208, CNNC)

26. Large scale Braided channel system of
Zhilou Formation in Husiliang area
(Team No. 208, CNNC)

27. 3.2 Erlian basin
--- Bayanwula Deposit
(Christophe, 2012)

28. 3.2.1 Stratigraphic Column in Erlian Basin

29. 3.2.2 Sedimentation system in
Bayanwula
Saihan Fm
Braided Braided
channel channel

30. Flooding plain
(Red mudstone)
Braided stream
(Braided channel sand bodies)
Fan delta
(Lacustrine mudstone and
distributary channel ) Culomn of BZK127-0 drilling hole

31. 3.2.3 General characters of ore bodies
No. B335 exploration profile showing the tabular
ores in west part of Bayanwula deposit

32. 155o
No. B319 exploration profile showing the
roll-front ores in east part of Bayanwula deposit

33. l
f
– L
f
• Roll f
of th
collis
Jaireth et al. 2008
Genesis model for Bayanwula deposit

34. 3.2.4 Bayantala sag in Erlian basin
----Huhe deposit
(Christophe, 2012)

35. Geological map derived
from RS image (TM7,4,1)
“Roof windows”-- the
outcrops of the Lower
Cretaceous (K1b)

36. Sedimentation characters of Saihan formation in Huhe
Saihantala Fm Depositional Lithological Climate Primary Organic
system assemblage color matter
Upper member Meandering Mudstone Arid Variegated Deficient
（ K1bs2 ） intercalated with color
sandstone
Lower member Braided Overlap of Warm Grey Abundant
（ K1bs1 ） braided channel and
sand bodies humid
ores
Tengge’er Fm -- fan delta

37. Uranium mineralization in Huhe deposit
• 200 to 300 m wide, 1600m long, buried at depths of 115 to 127m
• Tabular or lenticular in shape and 2.4 to 14m in thickness
• Grade: 0.01%~0.074%
No. 320 exploration profife of Huhe deposit

38. 4. Conclusions
a. Three formation model
--- favorable for U mineralization
• Lower Fm: dark coal-bearing formation of
lacustrine
• Middle Fm: grey sandstone formation of braided
channel
• Upper Fm: red mudstone formation of
meandering stream
two unconformities: between the lower and
middle, and between the middle and upper

39. b. favorable geological setting: tectonic
reversion of extension or depression basin
c. Favorable sedimentation system: fluvial
system braided channel to meandering
system, but braided channel sandstone is the
most important target for U
d. early-stage U mineralization: related to
phreatic oxidation or interlayer oxidation.
e. later-stage U mineralization: might related to
migration hydrocarbon as the reductant
along the faults or sandy strata ?

40. Thank you!