Rock Sample Description and Petrography

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1 GSA Data Repository Rock Sample Description and Petrography For the purposes of this study, zircons have been separated from a range of rock samples from the Coolac Serpentinite Belt, including two (high-al and high-cr) massive chromitites, leucogabbro, plagiogranite and rodingite. Detailed descriptions of sample site geology and sample petrography are given by Graham, Samples M104-M13 (high-cr) and ML101A (high-al) Chromitites: Massive polycrystalline chromitite consists of highly fractured, subrounded and closely packed chromite nodules, with less than 5% internodular space in-filled by serpentine. Post-formational textures are less prominent and range from discrete fractures to intense brecciation, in which the amount of dilation ranges from 0.5mm down to resolution limits. The fractures generally lack offsets and therefore have no significant shear component. Sample #238, Leucogabbro: The sample site is located within the western schistose margin of the central section of the Coo lac Serpentinite Belt where leucogabbro occurs as a segregation within a complex leucogabbro/hornblende gabbro body which contains numerous elongate enclaves of metabasalt, and veins and patches of pegmatitic hornblende gabbro. The leucogabbro has an allotriomorphic granular texture defined by interlocking grains of diopside, hornblende and plagioclase, cut by fibrous tremolite. It consists of 85% albite, 5% diopside, 5% tremolite, 5% hornblende and accessory zircon. Sample #20, Plagiogranite: The plagiogranites mostly exhibit an allotriomorphic granular texture, generally defmed by interlocking grains of quartz and albitic plagioclase along with cross-cutting fibrous grains of tremolite and mica. The mean modal composition of the plagiogranites is 60% quartz, 40% albite and contains 5% perthitic orthoclase, with trace amounts of tremolite, Na-rich white mica, epidote and zircon. Sample RH106, Rodingite: Grossular dominant rodingite has only been found at Mount Lightning. It is entirely composed of grossular and forms schistosity-parallel vein-fillings in schistose serpentinite. The contact between the grossular veinlets and serpentinite is sharp and the rodingite is massive and unfoliated.

2 Figure DR17 presents a photo of the outcrop with veinlets of rodingite at the chromitite location Chr-104 (or Artic Mine; Graham, 1998) of the Coolac Serpentinite Belt. Note that only samples of massive chromitites without visible cracks or veinlets were selected for zircon separation work. Sample Processing, Analytical Techniques and Methods To avoid cross-sample contamination during sample processing, the rocks were disaggregated using the selfrag (Selective Fragmentation) technique followed by conventional methods of zircon separation using heavy liquids and a Frantz magnetic separator at the GEMOC/CCFS Centre, Department of Earth and Planetary Sciences, Macquarie University, Sydney. Zircon separation procedure The selfrag (Selective Fragmentation) approach was used for disintegration of the rock samples. Most of the processed rock samples were over 5kg to achieve sufficient yield of zircon. They have been pre-crushed to about 3-4cm blocks and then processed using the selfrag S1.1 with the parameters set at 10mm gap, 200 pulses per cycle, frequency 3 pulses per second, and the voltage variable (115kv 140kv). The disaggregated samples were screened using 210µm disposable sieves and the <210µm fraction panned with a Russian Lotok (pan) to remove the bulk of the sample including the fines and the light material fraction. A non-magnetic fraction was separated from the panned concentrate using a Frantz LB-1 Magnetic Barrier Laboratory Separator set at 1.7A /ss=10 0 /fs=15 0 and then treated by heavy liquid separation in sodium polytungstate solution with density of ~3 to produce the final zircon concentrate. Zircon was then hand picked from the concentrate to a stainless steel stub with doublesided adhesive and then molded into an epoxy mount for subsequent lapping, polishing and analysis. Prior to the analyses all mounted grains were CL imaged to examine their internal structure using a Camebax SX 100 electron microprobe in the Geochemical Analysis Unit (GAU) of the GEMOC/CCFS Centre in the Department of Earth and Planetary Sciences, Macquarie University.

3 Zircon U Pb analysis Most of the zircons have been U-Pb dated by LAM-ICPMS technique at Macquarie University, while small zircons with grain size less than 50μm have been analysed using the SHRIMP ion microprobe of the John de Laeter Centre for Isotope Research at Curtin University, Perth, Australia. The zircon analyses followed standard operation procedures described by Compston et al. (1984) and Williams (1998). The mass resolution was >5000 and the primary (O - 2 ) beam was 0.6 na on a 15 µm spot. The zircon standard used was TEMORA-2 (416.8 Ma; Black et al., 2003). Data were processed using the SQUID and ISOPLOT program (Ludwing, 2003, 2009). Common Pb was subtracted from the measured compositions using the measured 204 Pb and a common Pb composition from the model of Stacey and Kramers (1975) at the approximate age of each analysis. LAM-ICPMS U Pb analyses were carried out using Agilent 7700 quadrupole ICP-MS instruments, attached to a Photon Machines Excimer 193 nm laser system. The analyses were carried out with a beam diameter of ca μm with 5 Hz repetition rate and energy of around 0.06 µj and 8J/cm2. The analytical procedures for the U Pb dating have been described in detail previously (Jackson et al., 2004). A very fast scanning data acquisition protocol was employed to minimise signal noise. Data acquisition for each analysis took three minutes (one minute on background, two minutes on signal). Ablation was carried out in He to improve sample transport efficiency, provide more stable signals and give more reproducible Pb/U fractionation. Provided that constant ablation conditions are maintained, accurate correction for U/Pb fractionation can then be achieved using an isotopically homogeneous zircon standard. Samples were bracketed at the beginning and end by pairs of analyses of the GEMOC GJ-1 zircon standard (Elhlou et al., 2006). This standard is slightly discordant, and has a TIMS 207 Pb/ 206 Pb age of Ma (Jackson et al., 2004). The other well-characterised zircon standard and Mud Tank were analysed within the run as an independent control on reproducibility and instrument stability. U Pb ages were calculated from the raw signal data using the online software package GLITTER ( Griffin et al., 2008). GLITTER calculates the relevant isotopic ratios for each mass sweep and displays them as time-resolved data. This allows isotopically homogeneous segments of the signal to be selected for integration. GLITTER then corrects the integrated ratios for ablation related fractionation and instrumental mass bias by calibration of each selected time segment against the identical time segments for the standard zircon analyses.

4 For zircon analyses we have employed the common-pb correction procedure of Andersen (2002) and the analyses presented here have been corrected assuming recent leadloss with a common-lead composition corresponding to present-day average orogenic lead as given by the second-stage growth curve of Stacey and Kramers (1975) for 238 U/ 204 Pb=9.74. No correction has been applied to analyses that are concordant within 2σ analytical error in 206 Pb/ 238 U and 207 Pb/ 235 U, or which have less than 0.2% common lead. Ion microprobe oxygen isotope analysis in zircon Oxygen isotope ratios ( 18 O/ 16 O) were determined using a Cameca IMS 1280 multi-collector ion microprobe located at the Centre for Microscopy, Characterisation and Analysis (CMCA), University of Western Australia (UWA). Oxygen isotope analyses were performed with a ca. 3 na Cs + beam with an impact energy of 20 kev focused to a ca. 15 µm spot on the sample surface. Instrument parameters included a magnification of 130 between the sample and field aperture (FA), 400 μm contrast aperture (CA), 4000 μm FA, 120 μm entrance slit, 500 μm exit slits, and a 40 ev band pass for the energy slit with a 5 ev gap toward the high energy side. Secondary O - ions were accelerated to 10 kev and analyzed with a mass resolving power of approximately 2400 using dual Faraday Cup detectors. A normalincidence electron gun was used to provide charge compensation and NMR regulation for magnetic field control. Ten seconds of pre-sputtering were followed by automatic centering of the secondary beam in the FA and CA. Each analysis consisted of 20 four-second cycles, which gave an average internal precision of 0.2 (2 SE). Analytical sessions were monitored in term of drift and precision using at least two bracketing standards (Temora II; 8.2 ; Black et al., 2004) every 5 sample analyses. Instrumental mass fractionation (IMF) was corrected using Temora II closely following the procedure described in Kita et al. (2009). The spot-to-spot reproducibility (external precision) was better than 0.3 (2 SD) on Temora II during all of the analytical sessions. Uncertainty on each δ 18 O spot has been calculated by propagating the errors on instrumental mass fractionation determination, including the error on the reference value of the standard, and internal error on each sample data point. The resulting uncertainty is typically between 0.2 and 0.3 (2 SD). Raw 18 O/ 16 O ratios and corrected δ 18 O (quoted with respect to Vienna standard mean ocean water or VSMOW) are presented in the Table 3 of the Data Repository.

5 Zircon Hf-isotope analysis Hf-isotope analyses were carried out in the Geochemical Analysis Unit of the GEMOC/CCFS Centre in the Department of Earth and Planetary Sciences, Macquarie University. The details of the methodology and analytical condition for Lu-Hf isotope analysis are provided by Griffin et al. (2000). Hf-isotope analyses were carried out in-situ using a New Wave/Merchantek UP-213 laser-ablation microprobe, attached to a Nu Plasma multi-collector ICPMS. The analyses were carried out with a beam diameter 40µm and a 5 Hz repetition rate and typical ablation times ca 100 s. He carrier gas transported the ablated sample from the laser-ablation cell via a mixing chamber to the ICPMS torch. Interference of 176 Lu on 176 Hf was corrected by measuring the intensity of the interference-free 175 Lu isotope and using 176 Lu/ 175 Lu = (DeBievre & Taylor 1993) to calculate 176 Lu/ 177 Hf. Similarly, the interference of 176 Yb on 176 Hf has been corrected by measuring the interference-free 172 Yb isotope and using 176 Yb/ 172 Yb to calculate 176 Yb/ 177 Hf. The appropriate value of 176 Yb/ 172 Yb was determined by spiking the JMC475 Hf standard with Yb, and finding the value of 176 Yb/ 172 Yb ( ) required to yield the value of 176 Hf/ 177 Hf obtained on the pure Hf solution. Detailed discussions regarding the overlap corrections for 176 Lu and 176 Yb are provided in Pearson et al. (2008). Precision and accuracy obtainable on the 176 Hf/ 177 Hf ratio are illustrated by analyses of standard zircons in Griffin et al. (2000) and Pearson et al. (2008). The typical 2SE precision on the 176 Hf/ 177 Hf ratios presented here is about , equivalent to +0.7 εhf unit. The Mud Tank and Temora zircon were used as independent control on reproducibility and instrument stability. Most of the data and the mean value are within 2 s.d. of the recommended values reported for Mud Tank ( 176 Hf/ 177 Hf = ±42 (2sd), Griffin et al., 2007) and Temora reference material ( ± 15, Kemp et al., 2005). For the calculation of εhf values, we have adopted the chondritic values of Bouvier et al. (2008): 176 Lu/ 177 Hf (CHUR, today) = , 176 Hf/ 177 Hf (CHUR, today) = and the decay constant for 176 Lu of x yr-1 (Scherer et al., 2001). To calculate model ages (TDM) based on a depleted-mantle source, we assume that the depleted mantle (DM) reservoir developed from an initially chondritic mantle, and is complementary to the crust extracted over time. T DM ages, which are calculated using the measured 176 Lu/ 177 Hf of the zircon, can only give a minimum age for the source material of the magma from which the zircon crystallised. Therefore we have also calculated, for each zircon, a crustal Model age (TDMC in Data tables) which assumes that its parental magma was produced from an average

6 continental crust ( 176 Lu/ 177 Hf = 0.015; Geochemical Earth Reference Model database, that was derived from a depleted mantle. Zircon trace-element analysis Trace element content was analysed using Agilent 7700 quadrupole ICP-MS instruments, attached to a Photon Machines Excimer 193 nm laser system at the GAU, Macquarie University. The analyses were carried out using the same laser condition as for U-Pb dating. Detailed descriptions of analytical and calibration procedures have been given by Belousova et al. (2002). Zirconium content was used for internal calibration and quantitative results for the trace elements reported here were obtained through calibration of relative element sensitivities using the NIST-610 standard glass as the external calibration standard. The precision and accuracy of the NIST-610 analyses are 1 2% for REE, Y, Sr, Nb, Hf, Ta, Th and U at the ppm concentration level, and from 5% to 10% for Ca, P and Ti. PGM Re-Os isotope analyses Polished thin sections of chromitite from a number of hand samples were studied by reflected light microscopy to locate platinum-group minerals (PGM). Then the PGM (laurite) were identified by their Energy Dispersive (EDS) X-ray spectra, and back-scattered images were taken of each mineral grain using a Scanning Electron Microscope (SEM) at the GAU in the GEMOC/CCFS Centre, Macquarie University. Single grains of PGM >5 μm across were selected for in situ Re Os isotope analysis carried out at GEMOC/CCFS using analytical methods described in detail previously (e.g. Pearson et al., 2002; Griffin et al., 2002; González-Jiménez et al., 2012). A New Wave/Merchantek UP 213 laser microprobe with a large-format cell was coupled with a Nu Plasma Multicollector ICP-MS. During the analysis of PGM all ion beams were collected in Faraday cups. The laser was fired at a frequency of 4 Hz, with energies of 1 2 mj/pulse and a spot size of 15 μm. A standard NiS bead (PGE-A) with 199 ppm Os (Lorand and Alard, 2001) and 187 Os/ 188 Os= (Pearson et al., 2002) was analyzed between samples to monitor any drift in the Faraday cups and ion counters. The overlap of 187 Re on 187 Os was corrected by measuring the 185 Re peak and using 187 Re/ 185 Re= All the analyzed grains have 187 Re/ 188 Os lower than 0.5, thus ensuring that the isobaric interference of 187 Re on 187 Os was precisely corrected (c.f. Nowell et al., 2008). The data were collected using the Nu Plasma

7 time-resolved software, which allows the selection of the most stable intervals of the signal for integration.

8 Table DR1. Locality information for the samples from the Coolac Serpentinite Belt and Young Granodiorite, Lachlan Fold Belt, NSW, Australia Sample Rock type Geographic Coordinates Longitude Latitude Geographic location Mineral recovered ML104-M13 High-Cr massive chromitite ' ' Quilter's open cut, Mt. Lightning Zircon ML100A & 101A High-Al massive chromitite ' ' Mary Mine, Mt. Lightning Zircon ML-104-F High-Cr massive chromitite ' ' Quilter's open cut, Mt. Lightning Laurite ML-104-M10 High-Cr massive chromitite ' ' Quilter's open cut, Mt. Lightning Laurite MCI-101-F1 Massive chromitite ' ' Massive chromitite filons in host dunite, ocurrence #35 of Graham (1998) None RH106 Rodingite ' ' South of Mt. Lighting Zircon #20* Plagiogranite Western margin of the central part of the Coolac Complex Zircon #238* Leucogabbro Western margin of the southern part of the Coolac Complex Zircon TC12-ML01 Stream sample ' ' Small ~1 m gully on the Northern slope of Mt. Lightning Zircon TC12-BG01 Stream sample ' ' Browngrow Creek, Eastern side of the Coolac Complex Zircon YG202 Young Granodiorite ' ' ~ 20 m East from the contact with the Coolac peridotite, SE side of Mt. Lightning Zircon * Ian Graham's samples as described in Graham et al. (1996 a, b) and Graham, 1998 PhD thesis

9 Table DR2. Zircon U- Pb age data for the samples from the Coolac Serpen>nite Belt and Young Granodiorite, Lachlan Fold Belt, NSW, Australia Analysis No. R A T I O S A G E S ( M a ) CONCENTRATIONS (ppm) 207 Pb/ 206 Pb ± 2σ 207 Pb/ 235 U ± 2σ 206 Pb/ 238 U ± 2σ 208 Pb/ 232 Th ± 2σ 207 Pb/ 206 Pb ± 2σ 207 Pb/ 235 U ± 2σ 206 Pb/ 238 U ± 2σ 208 Pb/ 232 Th ± 2σ Used Age ± 2σ Th U Plagiogranite # # # # # # # # # # # # # Leucogabbro #238-01C #238-01R #238-02C #238-02R #238-03R #238-03C # #238-06C #238-06R #238-07C #238-07R #238-08C #238-08R # # #238-11C #238-11R #238-12C #238-12R #238-13C #238-13R # # # #238-19R #238-20C #238-20R #238-23C #238-23R #238-24C #238-24R # #238-26C #238-26R

10 Analysis No. R A T I O S A G E S ( M a ) CONCENTRATIONS (ppm) 207 Pb/ 206 Pb ± 2σ 207 Pb/ 235 U ± 2σ 206 Pb/ 238 U ± 2σ 208 Pb/ 232 Th ± 2σ 207 Pb/ 206 Pb ± 2σ 207 Pb/ 235 U ± 2σ 206 Pb/ 238 U ± 2σ 208 Pb/ 232 Th ± 2σ Used Age ± 2σ Th U High-Cr massive chromitite ML104- M ML104- M ML104- M ML104- M ML104- M ML104- M High-Al massive chromitite *ML100A- 01C *ML100A- 01R *ML100A *ML100A *ML100A- 03C *ML100A- 04C *ML101A *ML101A- 01C ML101A ML101A Rodingite RH RH *RH *RH *RH106-05B *RH *SHRIMP analysis Stream sample, Northern slope of Mt. Lightning TC12- ML TC12- ML TC12- ML01-03R TC12- ML TC12- ML TC12- ML01-08C TC12- ML01-08R TC12- ML TC12- ML TC12- ML01-13C TC12- ML01-13R TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML01-23C TC12- ML01-23R TC12- ML

11 Analysis No. R A T I O S A G E S ( M a ) CONCENTRATIONS (ppm) 207 Pb/ 206 Pb ± 2σ 207 Pb/ 235 U ± 2σ 206 Pb/ 238 U ± 2σ 208 Pb/ 232 Th ± 2σ 207 Pb/ 206 Pb ± 2σ 207 Pb/ 235 U ± 2σ 206 Pb/ 238 U ± 2σ 208 Pb/ 232 Th ± 2σ Used Age ± 2σ Th U TC12- ML TC12- ML01-27C TC12- ML01-27R TC12- ML01-28C TC12- ML01-28R TC12- ML TC12- ML01-30C TC12- ML01-30R TC12- ML TC12- ML TC12- ML01-34C TC12- ML01-34R TC12- ML TC12- ML01-35C TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML01-5C TC12- ML01-5R TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML01-71C TC12- ML01-71R TC12- ML01-72C TC12- ML01-72R TC12- ML01-73C TC12- ML01-73R TC12- ML TC12- ML Stream sample, Browngrow Creek, Eastern side of the Coolac Complex TC12- BG TC12- BG TC12- BG TC12- BG01-15C TC12- BG01-15R TC12- BG

12 Analysis No. R A T I O S A G E S ( M a ) CONCENTRATIONS (ppm) 207 Pb/ 206 Pb ± 2σ 207 Pb/ 235 U ± 2σ 206 Pb/ 238 U ± 2σ 208 Pb/ 232 Th ± 2σ 207 Pb/ 206 Pb ± 2σ 207 Pb/ 235 U ± 2σ 206 Pb/ 238 U ± 2σ 208 Pb/ 232 Th ± 2σ Used Age ± 2σ Th U TC12- BG TC12- BG01-22C TC12- BG01-22R TC12- BG TC12- BG01-24C TC12- BG01-24R TC12- BG TC12- BG01-26C TC12- BG01-26R TC12- BG01-35C TC12- BG TC12- BG01-46C TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG Young Granodiorite YG YG202-06C YG202-06R YG202-07C YG202-07R YG202-08C YG202-08R YG202-10C YG YG YG YG YG YG202-25C YG202-25R YG202-26C YG202-26R YG202-27C YG202-32C YG202-32R YG202-36C YG202-36R YG202-37C YG202-37R YG YG YG202-51C YG202-51R YG YG202-53C YG202-53R

13 Table DR3. Zircon Hf- and O- isotope data for the samples from the Coolac Serpen=nite Belt and Young Granodiorite, Lachlan Fold Belt, NSW, Australia Analysis No. Lu- Hf R A T I O S O- ISOTOPES U- Pb A G E Hf 176 Hf/ 177 Hf 1SE 176 Lu/ 177 Hf Yb/ 177 ini=al εhf(t) ± SE T DM (Ga) Crustal T DM (Ga) Hf 18O/16O Rel. err in % δ18o 2 σ (Ma) 2 σ Plagiogranite # # # # #20-15* # # # # # # # Leucogabbro #238-01C #238-01R #238-02R #238-03R # #238-06R #238-08R # # #238-11C #238-11R #238-12R #238-13R # # # # #238-20C #238-20R #238-21C #238-21R #238-22C

14 Analysis No. Lu- Hf R A T I O S O- ISOTOPES U- Pb A G E Hf 176 Hf/ 177 Hf 1SE 176 Lu/ 177 Hf Yb/ 177 ini=al εhf(t) ± SE T DM (Ga) Crustal T DM (Ga) Hf 18O/16O Rel. err in % δ18o 2 σ (Ma) 2 σ #238-22R Plagiogranite #238-24C #238-24R #238-26C #238-26R #238-27C #238-27R #238-28C #238-28R High-Cr massive chromitite ML104- M ML104- M ML104- M ML104- M ML104- M13-04R ML104- M ML104- M13-05B ML104- M ML104- M13-06B ML104- M High-Al massive chromitite M100A- 01C M100A- 01R M100A M100A M100A- 03C M100A- 03R M100A- 04C M100A- 04R M100A ML101A ML101A- 05R ML101A ML101A ML101A ML101A

15 Lu- Hf R A T I O S O- ISOTOPES U- Pb A G E Analysis No. Hf 176 Hf/ 177 Hf 1SE 176 Lu/ 177 Hf 176 Yb/ 177 ini=al εhf(t) ± SE T DM (Ga) Crustal T DM (Ga) Hf 18O/16O Rel. err in % δ18o 2 σ (Ma) 2 σ ML101A- 12 Plagiogranite Rodingite RH RH RH RH106-05A RH106-05B RH Stream sample, Northern slope of Mt. Lightning TC12- ML01-08C TC12- ML01-08R TC12- ML01-13C TC12- ML01-13R TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML01-24* TC12- ML TC12- ML TC12- ML01-30C TC12- ML01-30R TC12- ML TC12- ML01-41* TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML

16 Analysis No. Lu- Hf R A T I O S O- ISOTOPES U- Pb A G E Hf 176 Hf/ 177 Hf 1SE 176 Lu/ 177 Hf Yb/ 177 ini=al εhf(t) ± SE T DM (Ga) Crustal T DM (Ga) Hf 18O/16O Rel. err in % δ18o 2 σ (Ma) 2 σ TC12- ML01-71C Plagiogranite TC12- ML01-71R *Grains- "survivors" Stream sample, Browngrow Creek, Eastern side of the Coolac Complex TC12- BG01-1C TC12- BG01-1R TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG01-15C TC12- BG TC12- BG TC12- BG01-22C TC12- BG01-22R TC12- BG TC12- BG01-24C TC12- BG01-24R TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG TC12- BG Young Granodiorite YG YG202-06C YG202-06R

17 Analysis No. Lu- Hf R A T I O S O- ISOTOPES U- Pb A G E Hf 176 Hf/ 177 Hf 1SE 176 Lu/ 177 Hf Yb/ 177 ini=al εhf(t) ± SE T DM (Ga) Crustal T DM (Ga) Hf 18O/16O Rel. err in % δ18o 2 σ (Ma) 2 σ YG202-07C Plagiogranite YG202-07R YG202-08C YG202-08R YG202-10C YG202-10R YG YG YG YG YG YG202-25C YG202-25R YG202-26C YG202-26R YG202-27C YG202-32C YG202-32R YG202-36C YG202-36R YG202-47C YG202-47R YG YG YG202-51C YG202-51R YG YG202-53C YG202-53R *Grains- "survivors"

18 Table DR4. Zircon trace- element data (ppm) for the samples from the Coolac Serpen=nite Belt and Young Granodiorite, Lachlan Fold Belt, NSW, Australia Analysis No. P Ti Y Nb La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta Pb Th U Th/U U/Yb Age (Ma) 2 σ Plagiogranite # # # # #20-15* # # # # # # # Leucogabbro #238-01C #238-01R #238-02C #238-02R #238-03R #238-03C # #238-06C #238-06R #238-07C #238-07R #238-08C #238-08R # # #238-11C #238-11R #238-12C #238-12R #238-13C #238-13R # # # #

19 Analysis No. P Ti Y Nb La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta Pb Th U Th/U U/Yb Age (Ma) 2 σ #238- #20C #238- #20R #238-23C #238-23R #238-24C #238-24R # #238-26C #238-26R High-Cr massive chromitite ML104- M ML104- M ML104- M ML104- M ML104- M ML104- M High-Al massive chromitite ML101A < ML101A Rodingite RH RH RH RH106-05B RH Stream sample, Northern slope of Mt. Lightning TC12- ML TC12- ML TC12- ML01-03R TC12- ML TC12- ML TC12- ML01-08C TC12- ML01-08R TC12- ML01-13C TC12- ML TC12- ML TC12- ML

20 Analysis No. P Ti Y Nb La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta Pb Th U Th/U U/Yb Age (Ma) 2 σ TC12- ML TC12- ML TC12- ML TC12- ML01-24* TC12- ML TC12- ML TC12- ML01-30C TC12- ML01-30R TC12- ML TC12- ML01-41* TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML TC12- ML Stream sample, Browngrow Creek, Eastern side of the Coolac Complex TC12- BG < TC12- BG TC12- BG TC12- BG01-15C TC12- BG TC12- BG TC12- BG01-22C < TC12- BG01-22R < TC12- BG TC12- BG Young Granodiorite YG YG202-06C YG202-07C YG202-07R YG202-08C YG202-08R YG202-10C

21 Analysis No. P Ti Y Nb La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta Pb Th U Th/U U/Yb Age (Ma) 2 σ YG YG YG YG YG YG202-25C YG202-25R YG202-26C YG202-26R YG202-27C YG202-32C YG202-32R *Grains- "survivors"

22 Table DR5. Re- Os isotope data for Laurite (Ru,Os)S 2 from massive (high- Cr)chromiBte, Quilter's open cut, Coolac SerpenBnite Belt Analysis No. 187Os/188Os 2σ 187Re/188Os 2σ ECR T RD (Ga) 2σ (Ga) ML F1A- PTO ML F1B- PTO ML F1- E- PTO ML F1- F- PTO ML F5- A- PTO ML M10A- PTO ML M10- B- PTO1a ML M10- B- PTO ML M10- C- PTO ML M10- DPTO

Zircons were separated using standard techniques of mineral separation, including a Wilfley

GSA DATA REPOSITORY 2011129 Dhuime et al. Analytical methods Zircons were separated using standard techniques of mineral separation, including a Wilfley table, a Frantz isodynamic separator and heavy liquid.