1. Fertility and endowment indices for mineral systems: examples for Zn-Pb systems David Huston All mineral provinces are not created equally

2. Fertility indicators Sillitoe (2012) Circum-Pacific porphyry copper provinces Fertility: Presence Endowment: Amount

3. Fertility indicators Possible controls on fertility and endowment Geodynamic environment Tectonic setting and events Evolution of atmosphere and hydrosphere Size of individual mineral systems Temporal distribution Paleoclimate Source volumes and concentrations Magmatic crystallisation history Preservation

4. Fertility indicators VHMS – rhyolite geochemistry and fertility Hart (2004); following Lesher et al. (1986)

5. Fertility indicators VHMS – Nd-Pb isotopes and endowment VHMS deposits Lode gold deposits Well endowed provinces: T 2DM within 200 myr of volcanic age  < 8.3

6. Fertility indicators Lead isotope patterns in the Abitibi-Wawa Subprovince Abitibi-Wawa has much lower μ than Eastern Goldfields

7. Fertility indicators Comparison of VHMS endowment, Archean terranes ProvinceCu + Zn + Pb endowment (t/km 2 ) North Pilbara20 Whundo120 Yilgarn Craton30 Teutonic zone45 Cue zone280 Superior Province45 Abitibi-Wawa Subprovince170 Uchi Subprovince10 Wabigoon Subprovince20 Slave Province35 Eastern Slave35 Western Slave35

8. Fertility indicators Leach et al. (2010) Link between metal endowment of paleolatitude of sediment- hosted Zn-Pb deposits Latitude from paleomagnetic data Probably related to formation of evaporites as salt source

9. Fertility indicators Hart (2004) Limitations to fertility and endowment indices Secular variations Unusual deposits (e.g., hybrid Cu- Au) can have unusual signatures Not “silver bullets”, but useful as indicators

10. Phone: +61 2 6249 9111 Web: www.ga.gov.au Email: David.Huston@ga.gov.au Address: Cnr Jerrabomberra Avenue and Hindmarsh Drive, Symonston ACT 2609 Postal Address: GPO Box 378, Canberra ACT 2601 Thank you