Territory Stories

Woodgreen, Northern Territory : explanatory notes

Details:

Title

Woodgreen, Northern Territory : explanatory notes

Issued by

Northern Territory Geological Survey

Collection

E-Publications; E-Books; PublicationNT; Australia 1:100 000 Geological Map Series

Date

2007

Location

Australia 1:100 000 Geological Map Wood 5458; Australia 1:250 000 Geological MapAlcoota SF5310; Australia 1:250 000 Geological MapAlcoota SF5310

Map scale

1:100 000

Notes

Made available via the Publications (Legal Deposit) Act 2004 (NT); Available from GEMIS - Geoscience Exploration and Mining Information System

Language

English

Subject

Geology; Georgina Basin; Arunta Region

Publisher name

Northern Territory Government; Northern Territory Government

Place of publication

Darwin

Edition

1st ed.

Series

Australia 1:100 000 Geological Map Series

File type

application/pdf

ISBN

9780724571321

ISSN

0811-6296

Use

Attribution International 4.0 (CC BY 4.0)

Copyright owner

Northern Territory Government

License

https://creativecommons.org/licenses/by/4.0/

Related links

https://geoscience.nt.gov.au/gemis/ntgsjspui/handle/1/81885 [GEMIS]

Parent handle

https://hdl.handle.net/10070/794795

Citation address

https://hdl.handle.net/10070/794807

Page content

1 3 Figure13. Boko For m a t i on. We l l de ve l ope d gl a c i a l s t r i a t i ons on l a r ge quartzite clast. 434259mE 7535454mN, 6.5 km E of Whiterock Dam. Figure14. Bo ko For m a t i on unc o nf or m a bl y ove r l yi ng ut opi a Q ua r t z i t e (? ). Fe r r ugi nous s a nds t on e a nd qua r t z i t e of ut opi a Q ua r t z i t e (? ) e xpo s e d i n f or e gr ound a nd t o l e f t of ve hi c l e . unc onf or m i t y s ur f a c e di ps w e s t be hi n d ve hi c l e , w i t h ge nt l y di ppi ng Boko Formation outcropping to right; be s t e xpos ur e i s a r ound t op of s m a l l hi l l (s e e Figure12 for detail). 428550mE 7555 0 1 5m n, 3 km nnW of ne w Bor e . a l s o i n c l u d e g r a n i t e a n d v e i n q u a r t z . it i s p o s s i b l e t h a t s o m e , o r a l l o f t h e c l a s t s h a v e b e e n r e w o r k e d f r o m t h e Bo k o Fo r m a t i o n , a n d t h a t a n y f a c e t s a n d s t r i a t i o n s h a v e b e e n r e m o v e d b y a b r a s i o n . Fa c e t e d a n d s t r i a t e d c l a s t s h a v e been reported in HUCKITTA (Freeman 1986). th e oo r a b r a ar k o s e u n c o n f o r m a b l y o v e r l i e s b a s e m e n t granite (432171mE 7552110mN) and quartzite (431655mE 7552292mN), and locally conformably(?), overlies the Bo k o Fo r m a t i o n . a s m a l l o u t c r o p o f t h e u n c o n f o r m i t y s u r f a c e o v e r t h e ut o p i a Q u a r t z i t e h a s a d i s t i n c t l y p o l i s h e d a n d s t r i a t e d a p p e a r a n c e , a n d m a y r e p r e s e n t a s m a l l r e l i c t o f a g l a c i a t e d p a v e m e n t (Figure16). th e s t r i a t i o n d i r e c t i o n (e a s t w e s t t r e n d ) i s s i m i l a r t o t h a t n o t e d f r o m b e n e a t h t h e Bo k o Fo r m a t i o n . th e oo r a b r a ar k o s e i s o v e r l a i n w i t h p r o b a b l e u n c o n f o r m i t y b y t h e el y u a h Fo r m a t i o n , a l t h o u g h t h e c o n t a c t i s p o o r l y k n o w n . th e t h i c k n e s s o f t h e f o r m a t i o n i s e s t i m a t e d a t 2 0 0 m n e a r 4 3 3 0 0 0 m e 7 5 5 1 0 0 0 m n, b u t r e g i o n a l t h i c k n e s s v a r i a t i o n s a r e p o o r l y k n o w n , d u e t o t h e i n c o m p l e t e n a t u r e o f m o s t s e c t i o n s . th e f o r m a t i o n a p p e a r s t o b e c o m p l e t e l y a b s e n t f r o m t h e n e a r b y d i a m o n d d r i l l h o l e cms3. it i s a l s o a bs e nt f r om hol e s cms2 a nd cms4, g e n e t i c s i m i l a r i t i e s . Fo r t h i s r e a s o n , t h e k n o w n d i s t r i b u t i o n o f t h e u n i t i s e x t e n d e d , a l t h o u g h t h e f o r m a t i o n i s c l e a r l y l e n t i c u l a r a n d p r o b a b l y n o t c o n t i n u o u s b e t w e e n a l l l o c a l i t i e s . in Woodgreen, t h e oo r a b r a ar k o s e i s r e c o g n i s e d i n d i s c o n t i n u o u s o u t c r o p s f r o m t h e ku n o t h kn o b a r e a t o t h e r e g i o n e a s t o f ne w Bo r e . ne a r ku n o t h kn o b , t h e oo r a b r a ar k o s e c o n s i s t s o f m a s s i v e , p o o r l y s o r t e d , c o a r s e - g r a i n e d a n d p e b b l y a r k o s e . al t h o u g h s p a r s e l a r g e r p e b b l e s a n d c o b b l e s m a y b e w e l l r o u n d e d , t h e m a t r i x i s c o m p r i s e d o f a n g u l a r c l a s t s . th i s m a t e r i a l h a s a p p a r e n t l y b e e n d e r i v e d f r o m t h e e r o s i o n o f m a i n l y g r a n i t i c r o c k s , w i t h r e l a t i v e l y l i t t l e t r a n s p o r t a n d m i n i m a l c h e m i c a l w e a t h e r i n g . Significant facies changes occur between the Kunoth Knob area and the outcrops east of New Bore; the latter exposures c o m p r i s e i n t e r b e d d e d m u d s t o n e , s a n d s t o n e , c o a r s e a r k o s e a n d c o b b l e c o n g l o m e r a t e (Figure15), w i t h a p r o n o u n c e d h i g h r a d i o m e t r i c r e s p o n s e . sp e c t a c u l a r e x p o s u r e s o f c o b b l e conglomerate are present around 433280mE 7551039mN. th e s e s t a c k e d l e n t i c u l a r b o d i e s a r e i n f e r r e d t o r e p r e s e n t fluvial channels. Clasts are dominated by quartzite, but