2015 broken hill resources investment symposium - geological survey of new south wales - phil...

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Uncovering the Curnamona and surrounds: a New South Wales perspec:ve Phil Gilmore Ac-ng Manager, Regional Mapping & Explora-on Geoscience Geological Survey of NSW

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Uncovering  the    Curnamona  and  surrounds:    a  New  South  Wales  perspec:ve

Phil  Gilmore  Ac-ng  Manager,  Regional  Mapping  &  Explora-on  Geoscience  

Geological  Survey  of  NSW  

Contents  •  Where  is  ‘Curnamona  and  surrounds’?    •  Why  does  GSNSW  care?  

•  What  has  GSNSW  been  doing?  

‘Curnamona  and  surrounds’    •  Includes:  

•  NSW  part  of  the  Curnamona  Craton  

•  Parts  of  the  Delamerian  and  Thomson  orogens  

•  Younger  basins  –  Palaeozoic,  Mesozoic,  Cenozoic  

Why  do  we  care?  •  Mineral  and  energy  endowment  

•  Elephant  country  •  Proven  concepts  •  Lots  of  smoke  (>4800  mineral  occurrences)  •  Under  explored  •  Infrastructure  and  know-­‐how  

•  1.7  billion  years  of  geology  to  research  •  Cri-cal  area  for  eastern  Australian  geodynamics  •  Challenges  of  cover  

Curnamona  Craton  •  Broken  Hill  and  Olary  domains  •  ~1710  –1640  Ma  deposi-on  of  metasedimentary  and  

metavolcanic  rocks  (Willyama  Supergroup)  plus  intrusions  •  ~?1640–1580  Ma  intense  deforma-on  and  metamorphism  

in  the  Olarian  Orogeny  •  ~1600–1580  Ma  intrusive  rocks  (e.g.  Mundi-­‐type)  

 Joel  Fitzherbert’s  talk  •  And  of  course  the  Broken  Hill  ore  body  

•  300  Mt  @  20%  combined  Pb  +  Zn,  80  g/t  Ag  •  A$75  billion  in  ground  value  

Large et al. (2002)

Curnamona  Craton  •  Despite  huge  advances  in  understanding  the  forma-on  of  the  ore  body  and  

explora-on  models  for  BHT  …  it’s  a  challenge  •  Some  basic  rules  (stra-graphy  and  classic  indicators)  •  But  need  mul--­‐tool  and  mul--­‐scale  explora-on  …  and  drilling  

Groves et al. (2008) Stevens (2004)

Curnamona  Craton  •  Other  economic  systems  known  

–  e.g.  Pyrite  Hill  cobalt  •  20.8  Mt  @  1.87lb/t  (850ppm)  Co1  

 •  What  about  other  mineralised  systems?  

–  Proven  processes  –  Economic?  –  IOCG?  

Source: Reid (2009) after Stevens et al. 2008, Cooper and Tuckwell 1974

1 – Broken Hill Prospecting (2011)

Delamerian  Orogen  •  Neoproterozoic  to  Cambrian  rocks  •  Unconformably  overlie  Broken  Hill  and  Olary  domains  •  Range  of  sedimentary  and  igneous  protoliths  •  First  deformed  in  Delamerian  Orogeny  (~510-­‐495  Ma)  

 Glen  Phillip’s  talk    

Thomson Orogen

Delamerian Orogen

Arrowie Basin

Iron  ore  (magne-te)  •  e.g.  Hawsons  (Carpentaria)  •  Hosted  in  Braemar  Ironstone  (~660Ma)  •  215  Mt  @  mass  recovery  16.2%  magne-te  for  35  Mt  

premium-­‐grade  concentrate  (indicated)  1  

 MVT  or  stra-form  base  metals  •  MVT  intersected  at  Dome  5  in  basal  conglomerates  and  

carbonate  sequences  <300m  cover  (age  uncertain)  •  0.8  m  @  4.9%  Pb,  19.2%  Zn  and  83g/t  Ag  in  DF6  

•  Variscan  Mines  aqer  Teck,  Platsearch  

Thomson Orogen

Delamerian Orogen

Arrowie Basin

Dome 5

Hawsons

1 – maiden resource, Carpentaria, March 2014

Ni  (±  Cu,  PGE)    •  Red  Hill  (Impact  Resources)  drilling  lodes  within  

ultramafic  sills  and  dykes  •  Age  uncertain  but  cross  cut  Willyama  SG  •  Rodinian  riqing  ~830Ma?  

•  Orthomagma-c  systems  in  Koonenberry  Belt  •  Discovered  by  Inco  •  Hosted  in  Neoproterozoic  (~585  Ma)  alkali  

basalts  and  ultramafic  lavas  and  intrusions  

Thomson Orogen

Delamerian Orogen

Arrowie Basin

Mt Arrowsmith

Red Hill

Cu-­‐Zn-­‐Pb-­‐Ag  •  Cambrian  mafic-­‐peli-c  volcanic  associated  massive  

sulfide  (VAMS)  systems  •  FW  –  MORB  basalt,  HW  –  exhala-ves    •  Resource  (indicated)  at  Grasmere:    

•  3.02  Mt  grading  1.15%  Cu,  0.3%  Zn,  0.06  g/t  Au,  and  2.53  g/t  Ag1    

•  Structural  repe--on  and  upgrading  

Pb-­‐Ag  •  Thackaringa-­‐style  veins  •  Orogenic  veins  

•  Delamerian  Orogeny  ~500  Ma  

Thomson Orogen

Delamerian Orogen

Arrowie Basin

Grasmere Thackaringa

1.  Black  Range    Minerals  2006    

Post-­‐Delamerian  Orogeny  •  Porphyry  Cu-­‐Au  (polymetallic)  

–  Mount  Daubeny  basin  •  Late  Silurian  pull-­‐apart  basin  with  Cu,  Pb,  Ag  mineralisa-on  

–  Under  explored  calc-­‐alkaline  diorites  (e.g.  Quarry  Hill)  

•  Porphyry  poten-al?  

Thomson Orogen

Delamerian Orogen

Arrowie Basin

Mt Daubeny

Quarry Hill

Post-­‐Delamerian  Orogeny  •  Bendigo-­‐style  orogenic  Au  in  slates    •  Mainly  east  of  Koonenberry  Fault  –  300  km  

strike  •  Benambran-­‐aged  (~440  Ma)  mineralisa-on  

Thomson Orogen

Delamerian Orogen

Arrowie Basin

Warratta

Greenfield and Reid (2006) Victorian  Goldfields  (Ramsay,  1998)  

Devonian  basins  •  Darling  Basin  •  Actually  range  from  Late  Silurian  to  

Carboniferous  –  though  mostly  Devonian  •  ~  8000m  of  sedimentary  rocks  in  dis-nct  

structural  depressions  

Mesozoic  basins  •  Eromanga  Basin:  Jurassic  to  Cretaceous  (~199-­‐93  Ma)  •  Berri  Basin:  Lower  Cretaceous  (~125-­‐100  Ma)  •  Terrestrial  to  marine  sedimentary  rock  sequences  in  

both  basins  •  Gold  in  basal  Eromanga  Basin  

Eromanga Basin

Berri Basin

Emergent .The Granites

. Easter Monday . Tunnel Hill

Tibooburra Inlier

Work and slides by Steve Hill

Tunnel Hill

Cenozoic  basins  Murray  Basin  mineral  sands  

–  Intracratonic  basin  up  to  <600m  thick  –  Paleocene  to  Quaternary  (<60  Ma)  –  World  class  mineral  sand  deposits  

•  David  Forster’s  talk  Lake  Eyre  Basin    •  Fluvial  to  lacustrine  sequence  up  to  400m  

thick  (thickest  to  west,  south)  –  Paleocene  to  Quaternary  (<60  Ma)  –  Poten-al  for  Palaeochannel-­‐hosted  roll  

front  U  systems  in  NSW  •  SA  leading  the  way  

Lake Eyre Basin

Murray Basin

What  has  GSNSW  been  doing?  

What have the Romans ever done for us?

Geophysics  and  spectral  data  •  Available  by  250k  map  sheet  •  Aeromagne-c  

–  25  m  grid,  160  000  line  km    •  Radioelement  

–  Reprocessed  data  –  Special  uranium  stretches  

•  Gravity  –  2x2  km  grid    

•  Spectral  –  ASTER,  HyMap,  Hylogger  

•  Plus  seismic,  poten-al-­‐field  /  3D  modelling  and  lessons  for  interpre-ng  (Rosemary’s  talk)  

New  genera-on  mapping  –  Seamless    •  Best  available  mapping  •  Consistent  geodatabase  •  No  map  sheet  or  scale  capture  issues  •  Strato-­‐tectonic  layers  

•  Curnamona,  Delamerian,  Devonian  etc  •  Consistent  stra-graphy  •  Avribu-on  in  two  streams  

•  Source  –  scale,  how  captured    •  Geological  –  age,  lithology,  deposi-onal  

environment  etc  

Seamless  geology  –  what’s  in?  •  Previous  mapping  

–  25k  lithological  and  100k  stra-graphic  mapping  from  1970s  and  1980s  

•  Previous  compila-on  –  Bill  et.  al’s  ‘bheimoth’  (BHEI  2009)  –   –Palaeoproterozoic  to  Neoproterozoic  

Seamless  geology  –  what’s  in?  •  Koonenberry  Belt  

–  4  x  25k  geology  –  12  x  100k  geology  –  4  x  100k  regolith  

•  Geophysical-­‐geological  and  solid  geology  interpreta-ons    –  Loch  Lilly-­‐Kars  –  Koonenberry  Belt  250k  solid  

geology    –  Milparinka  250k,  Cobham  Lake  

250k  and  western  division  

1.  Sharp  et  al.  2006  2.  Gilmore  et  al.  2010.  3.  Hegarty  2011,  2010,  in  prep.  respec-vely      

Mineral  systems  •  Broken  Hill  special  250k  metallogenic  map  

–  Includes  updated  classifica-ons  and  review  of  metamorphism  (Joel’s  talk)  

•  Koonenberry  Belt  –  Mineral  systems  study  (2010)    

•  Ongoing  research  –  e.g.  intrusion  related  Sn,  REE,  U  

•  Collabora-on  with  Geoscience  Australia  –  Pb  isotope  map  (Huston  et  al.  2013)  –  MUM  geochronology  Koonenberry  

Juvenile  

Evolved  

Approximate  uncertainty  

Huston  et  al  (2013)      

Drilling  support  •  Coopera-ve  drilling  in  the  area  

–  Impact  Minerals  (Red  Hill)  •  $121k  to  test  below  workings  •  Intersected  high  grade  Ni  and  Cu  

–  Ausmon  Resources  (Nuntherungie)  •  $39k  to  test  porphyry  system  •  S-ll  to  be  drilled  

•  EC  Andrews  Drillcore  Facility  in  Broken  Hill  –  80  000m  storage,  viewing  

 

GDW  •  Geoscien-fic  Data  Warehouse  

–  GSNSW  maps  georeferenced  –  GSNSW  point  data  (e.g.  geochron)  –  Open  file  explora-on  data    

•  An  example  from  our  system  –  18  500  drill  holes    –  5  400  have  Cu  assays,    –  13  600  have  Pb  assays  –  Max  value  per  hole  plots  

 

hvp://dwh.minerals.nsw.gov.au/CI/warehouse  

The  MoU  •  Memo  of  Understanding  between  NSW  and  South  

Australia    

•  From  the  Geological  Survey  point  of  view  –  Developing  Curnamona  wide  seamless  geology  

•  Understanding  the  geology  beneath  cover  sequences  

•  Understanding  the  cover  –  Mineral  systems  

•  Includes  Uncover  Curnamona  technical  day,  field  trip  

Conclusions  •  ‘Curnamona  and  surrounds’  =  massive  area  

–  A  lot  of  metal    –  A  lot  of  concepts  –  A  lot  of  poten-al  

•  GSNSW  wants  to  see  more  mines  –  So  aiming  to  reduce  explora-on  risk  

•  Precompe--ve  data  •  Coopera-ve  drilling  •  Ideas  •  Technology  

•  Internally  and  via  collabora-on  

Thanks