GSA Data Repository Denyszyn, et al., 2018, A bigger tent for CAMP: Geology,

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1 GSA Data Repository Denyszyn, et al., 2018, A bigger tent for CAMP: Geology, SPPLEMENTARY FILE: Methods and Data Geochemistry Methods Bulk-rock compositions of the samples from the LBMC intrusion were determined by X-Ray Fluorescence (XRF) and inductively coupled plasma-mass spectrometry (ICP-MS), following open vessel multi-acid digestion at Geoscience Laboratories ( Geolabs ), Sudbury, Canada. Major and minor elements have been determined with an accuracy typically better than 2% and a 2-sigma external precision 3%, whereas most trace elements have been determined with an accuracy of 6% and a precision of 6% (2-sigma). A detailed discussion on the accuracy and precision is presented in Appendix A1 of Locmelis et al (2016). CA-ID-TIMS -Pb Geochronology Two samples were selected for geochronological analysis, one from near the roof of the intrusion and one from near the base. Sample PDR-12 is a pyroxenite near the contact with the Kinzigite Formation, whereas sample AD-15 is from the dunite at the base (Fig. 1B, C). Sample PDR-12, a pyroxenite, was fragmented using the Selfrag electric pulse disaggregator at Curtin niversity, Perth, and mineral-separation procedures using magnetic susceptibility and density filtration methods were used at the niversity of Western Australia, Perth, to isolate a non-magnetic, dense concentrate. Several small (ca. 100 microns in longest dimension) euhedral zircons were isolated, mostly stubby though some had a more elongate habit. Multiple populations were indicated based on colour; while most were colourless, some had a brown hue. Sample AD-15, a dunite, was crushed and pulverized using a hydraulic press and disc mill at WA; all other procedures were identical to those used for sample PDR-12. Several small, colourless, equant zircon grains were isolated from this sample. Grains selected after optical inspection to avoid grains with inherited cores (none were found) were pre-treated based on the chemical-abrasion technique after Mattinson (2005), with a hightemperature annealing step at 850 C for 60 hours followed by a leaching step in hydrofluoric acid at 180 C for 12 hours. Six single grains were selected, photographed, and were cleaned with concentrated distilled HNO3 and HCl. Due to their small size, no chemical separation methods were required. For ID-TIMS analysis, the samples were spiked with an in-house 205 Pb- 235 tracer solution, which has been calibrated against SRM981, SRM 982 (for Pb), and CRM 115 (for ), as well as an externally-calibrated -Pb solution (the JMM solution from the EarthTime consortium). This tracer is regularly checked using synthetic zircon solutions that yield -Pb ages of 500 Ma and 2000 Ma, provided by D. Condon (BGS). Dissolution and equilibration of spiked single crystals was by vapour transfer of HF, using Teflon microcapsules in a Parr pressure vessel placed in a 200 C oven for six days. The resulting residue was re-dissolved in HCl and H3PO4 and placed on an outgassed, zone-refined rhenium single filament with 5 µl of silicic acid gel. Pb isotope analyses were carried out using a Thermo Triton T1 mass spectrometer at niversity of Western Australia, using a

2 secondary electron multiplier in peak-jumping mode. ranium was measured as an oxide (O2). Fractionation and deadtime were monitored using SRM981 and SRM 982. Mass fractionation was %/amu. decay constants are from Jaffey et al. (1971). Data were reduced and plotted using the software packages Tripoli (from CIRDLES.org) and Isoplot 4.15 (Ludwig, 2012). All uncertainties are reported at 2σ, decay constant uncertainties not included. REFERENCES CITED Jaffey A.H., Flynn K.F., Glendenin L.E., Bentley W.C., and Essling A.M., 1971, Precision measurements of half-lives and specific activities of 235 and 238 : Physics Reviews C, v. 4, p Locmelis, M., Fiorentini, M. L., Rushmer, T., Arevalo, R., Adam, J., and Denyszyn, S. W., 2016, Sulfur and metal fertilization of the lower continental crust: Lithos, v. 244, p Ludwig, K. R., 2012, Isoplot/Ex, v Berkeley Geochronology Center Special Publication, 5. Mattinson, J. M., 2005, Zircon Pb chemical abrasion ( CA-TIMS ) method: combined annealing and multi-step partial dissolution analysis for improved precision and accuracy of zircon ages: Chemical Geology, v. 220, p FIGRE CAPTIONS Figure DR1: Photomicrograph of zircons extracted from sample PDR-12. Figure DR2: Photomicrograph of zircons extracted from sample AD-15.

3 Sample wt. (μg) (ppm) Pb c (pg) mol% Pb* Th 206 Pb Pb 207 Pb Pb 207 Pb 206 Pb ρ 206 Pb/ 238 Age (Ma) (Ma) 207 Pb/ 206 Pb Age (Ma) (Ma) AD-15: 1 crystal per fraction PDR-12: 1 crystal per fraction Table DR1: -Pb isotopic data for zircons from the La Balma Monte Capio Intrusion. Sample weights are calculated from crystal dimensions and are associated with as much as 50% uncertainty (estimated) Pb c = Total common Pb including analytical blank ( pg per analysis). Blank composition is: 206 Pb/ 204 Pb = , 207 Pb/ 204 Pb = , 208 Pb/ 204 Pb = (all 2σ), and a 206 Pb/ 204 Pb 207 Pb/ 204 Pb correlation of 0.9. Th/ calculated from radiogenic 208 Pb/ 206 Pb and age. Measured isotopic ratios corrected for tracer contribution and mass fractionation ( %/amu). ρ = error correlation coefficient of radiogenic 207 Pb/ 235 vs. 206 Pb/ 238. All uncertainties given at 2σ Ratios involving 206 Pb are corrected for initial disequilibrium in 230 Th/ 238 using Th/ = 4 in the crystallization environment. Table DR2

4 Fig. DR1

5 Fig. DR2