MSDP insights from new GSSA mapping
Stacey McAvaney, Mario Werner, Carmen Krapf, Mark Pawley, Ben Nicolson and Claire Wade
11th August 2016, Mineral Systems Drilling Program Open Day Outline
• Southern Gawler Ranges margin GSSA project
• Mapping as part of the Mineral Systems Drilling Program
• Map products and releases
• MSDP Map Series
• Southern Gawler Margin Regolith Map
• Mapping highlights
Department of State Development 2
Southern Gawler Ranges margin project
• Characterise mineral systems associated with GRV-HS magmatism
• Lithological and structural controls on mineralisation
• 1590 Ma palaeosurface
• Thickness of GRV Department of State Development 3 MSDP Mapping
Department of State Development 4 Role of field mapping in drilling program
• Constrain interpretation of geophysics
• Stratigraphy
• Structural geology and tectonic evolution
• Regional vs deposit-scale alteration systems
• Two-dimensionality of contact relationships
Department of State Development 5 Field mapping 669 Field observations 169 rock samples 62 geochemistry analyses 57 thin sections 13 geochronology samples
Department of State Development 6 Field mapping data delivery
www.sarig.pir.sa.gov.au/Map
Department of State Development 7 Geological core logging
Department of State Development 8 MSDP Mapping products
Department of State Development 9 Six Mile Hill Surface Geology
Department of State Development 10 previous mapping new mapping
Department of State Development 11 Regolith Map of the southern Gawler Ranges Margin
https://sarigbasis.pir.sa.gov.au/WebtopEw/ws/samref/sarig1/image/DDD/RB201600015.pdf Department of State Development 12 Regolith material
Regolith landforms Regolith transported vs. in situ Nine Mile Dam Six Mile Hill vitric tuff New outcrops of lower GRV Roopena Basalt northern extension of known outcrop
O’Reily Dam felsic porphyritic volcanic
Parkinson Dam quartz-phyric rhyolite lava
agate
10 km Department of State Development 14 Six Mile Hill Bimodal mafic and effusive-explosive felsic volcanic Sequence in lower GRV
Department of State Development 15 Six Mile Hill
Lanzarote, Canary Islands
Department of State Development 16 Peltabinna Volcaniclastic marker horizon in upper GRV siltstone
Pondanna Dacite
mud flow deposit
Eucarro Rhyolite debris flow deposit
Department of State Development 17 Peltabinna Volcaniclastic marker horizon in upper GRV outcrop MSDP 05 & 07
Department of State Development 18 Peltabinna Quartz-muscovite-fluorite greisen alteration in Hiltaba Suite granite
enriched in Sn (114 ppm), Cu (163 ppm), Zn (197 ppm), Pb (125 ppm), Bi (37 ppm), As (5 ppm), Sb (0.4 ppm)
depleted in K2O (3.2 wt%), Na2O (0.1 wt%), CaO (0.3 wt%), Sr (7 ppm)
muscovite altn in granite malachite staining in granite
TMI 10 km
qtz-mu replacement of fdspar greisen
cpy
100K geology 10 km Department of State Development 19 Plutonic to subvolcanic facies of GRV – Mount Double Hiltaba Suite along southern GRV margin andesite dyke dacite dyke rhyolite dyke
Waulkinna Hill Tin Hut
10 km
Department of State Development 20 Mount Double Archaean vs Palaeoproterozoic granitic basement? Sleaford Complex Pinbong Suite 2550–2440 Ma (1735–1700 Ma) Waddikee Rocks Poverty Corner
Peter Pan Platforms Little Pinbong Rockhole
Department of State Development 21 Mount Double Sleaford Complex Pinbong Suite
Department of State Development 22 Future directions
• Defining new volcanic succession at Six Mile Hill
• Significance and lithospheric/tectonic controls on basaltic magmatism on eastern margin of GRV
• Olarian faulting, potential controls on volcanism
• Hutchison Group stratigraphy: resolving ~2550 Ma, ~1790 Ma and ~1740 Ma max. dep ages
Department of State Development 23
Contact
Department of State Development Level 4, 101 Grenfell St Adelaide, South Australia 5000 GPO Box 320 Adelaide, South Australia 5001 T: +61 8 8463 3162 E: [email protected] www.statedevelopment.sa.gov.au