Jurassic carbonatite and alkaline magmatism in the Ivrea Zone (European Alps) related to the break-up of Pangea

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1 GSA DATA REPOSITORY Jurassic carbonatite and alkaline magmatism in the Ivrea Zone (European Alps) related to the break-up of Pangea A. Galli, D. Grassi, G. Sartori, O. Gianola, J.-P. Burg, M.W. Schmidt Department of Earth Sciences, ETH Zurich, Sonnegstrasse 5, CH-8092 Zurich DR1. ANALYTICAL METHODS BULK ROCK ANALYSES Sample preparation Forty-four fresh and homogeneous samples representing carbonatites (6 samples), marbles (3 samples), leucocratic enclaves within carbonatite VF (5 samples), oligoclasite dykes (9 samples), syenite (1 sample), alkaligabbros/diorites (2 samples), gabbros related to carbonatite VF (2 samples), hornblendites (6 samples) and pyroxenite enclaves within carbonatite VM (10 samples) were collected and analyzed for major and trace elements. A saw was used to reduce the size of the samples and remove the weathered surfaces. For each sample > 5 kg material were crushed using a vertical mill and a jawbreacker. Ca 60 g of crushed material were separated using a splitter and grounded in an agate mill for 4 minutes to have a homogeneous powder. XRF analyses Powders were dried in an oven at 105 C for at least 10 hours. 1.6 g of each powder were heated at 1050 C for 2 hours and weighed again in order to calculate the loss of ignition (LOI). Samples were mixed with di-lithiumtetraborate (Li 2B 4O 7) using a ratio 1:5 (5x Li 2B 4O 7 for 1x rock powder) and fused to circular glass pills with a Claisse M4 Fluxer. Major element composition was determined by X-ray fluorescence (XRF) at the Institute of Geochemistry and Petrology at ETH Zurich using a wave-length dispersive XRF spectrometer Axios of PANanalytical equipped with 5 crystals. LA-ICP-MS Trace elements were determined by Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICP-MS) on single fragments of crushed glass pills (the same as used for the XRF analyses) using a 193 nm (ArF) Excimer laser (Coherent, Germany) attached to a NexION 2000 (PerkinElmer, USA) quadrupole ICP-MS. An in-house made ablation cell flushed with He carrier gas (5.0 purity grade, ca. 1 L.min 1 ) was used for analyses. Sample gas consisting of ca. 1 L.min 1 Ar (5.0 purity grade) was admixed to the carrier gas downstream of the ablation chamber, before introduction to the plasma. The laser repetition rate was fixed to 10 Hz for all analyses. The NIST SRM610 glass standard was ablated using a 40 μm spot and an energy density of ca J.cm 2. For all other materials (di-lithiumtetraborate blank, BCR-2 standard and unknowns), a 100 μm spot size and an energy density of ca. 15 J.cm 2 were used, except for the blank that was ablated using ca. 25 J.cm 2. Trace element concentrations in the unknowns were calibrated against NIST SRM610 as external standard, using classical sample-standard bracketing (NIST SRM610 analysed twice every 5 samples). Every sample was analysed three times, the final concentration and uncertainty corresponding to the aver and 2 S.D. (standard deviation) of the three analyses. Data processing was performed using the Matlab-based SILLS program v (Guillong et al., 2008). The concentrations in the unknowns were i) blank-corrected using repeated analyses of di-lithiumtetraborate glass free from any rock powder and using Li concentration thereof (10 wt.%) as internal standard, and ii) corrected from sensitivity difference relative to NIST SRM610 using Ca (measured wt.% CaO from XRF analyses) as internal standard. The BCR-2 basalt (USGS), prepared in di-lithiumtetraborate glass using the same procedure as the unknowns, was repeatedly analysed as a secondary standard and processed as an unknown to check for the accuracy of the calculations. The obtained concentrations are all accurate within ±10% of the reference values of Jochum et al. (2016).

2 ZIRCON INVESTIGATION Zircon separation, imaging and study of inclusions Samples were reduced to fine sand by high volt pulse power fragmentation (SELFRAG) at ETH Zurich and sieved. The fraction between 32 µm and 400 µm was used for separation by a Holman and Wilfley gravity separation table. Zircons were handpicked and mounted in epoxy resin. After polishing and coating, zircon internal structures were visualized with a JEOL JSM-6390 LA scanning electron microscope (SEM) equipped with a LaB6-filament and a Centaurus CL detector. Mineral inclusions within zircons were investigated by a DILOR Labram micro-raman spectrometer with an exciting wavelength of nm. Zircon U-Pb dating and trace element composition Zircon U-Pb isotopic analyses were carried out at ETH Zurich by laser ablation inductively coupled plasma sector field mass spectrometry (LA-ICP-SF-MS) using a RESOlution (ASI, Australia) 193 nm ArF excimer laser system attached to an Element XR (Thermo, Germany) sector-field mass spectrometer. A laser repetition rate of 5 Hz, a spot size of 29 μm and a laser energy density of ca. 2.5 J cm 2 were used. Ablation was performed in a S-155, volume-constant ablation cell (Laurin Technic, Australia) characterized by a <1 cm 3 aerosol dispersion volume. It was fluxed during ablation with carrier gas consisting of 0.7 L min 1 high-purity He (5.0 grade) mixed with sample gas consisting of ca. 1.0 L min 1 high-purity Ar (6.0 grade). Data were acquired using time resolved-peak jumping and triple detector mode (SEM, analog and faraday). The monitored masses (dwell time in ms) were 202 Hg (10), 204 (Hg+Pb) (10), 206 Pb (75), 207 Pb (75), 208 Pb (10), 232 Th (10), 235 U (10) and 238 U (20), for a total sweep time of 0.25 s. A total of 240 mass scans were acquired over 60 s measurement (30 s of gas blank measurement followed by 30 s of sample ablation). The data were subsequently corrected offline for gas blank, downhole Pb/U fractionation, and instrumental drift and offset using the Igor Pro Iolite software (Paton et al., 2011), specifically the VizualAge data reduction scheme (Petrus and Kamber 2012). Downhole 206 Pb/ 238 U fractionation during sample ablation was corrected for each analysis using an exponential fit based on all analyses of the GJ-1 zircon reference material (Paton et al. 2010). All ratios were corrected from mass bias, instrumental offset and drift throughout the analytical session by classical standard-sample bracketing (2 standards every ca. 30 samples), using GJ-1 zircon standard (Jackson et al. 2004) as a primary reference material. Secondary standards ( 206 Pb/ 238 U of 1065 Ma, Wiedenbeck et al., 1995), Plešovice ( 206 Pb/ 238 U of 337 Ma, Sláma et al., 2008) and AusZ 7-1 ( 206 Pb/ 238 U of 38.9 Ma, Kennedy et al., 2014) were used for data quality control. Spots showing an alumina content higher than the limit of detection were not taken into account, as they were considered to show the influence of inclusions. The results were displayed on a Wetherills Concordia diagram using the software Isoplot v.3.0 (Ludwig, 2003). The error on the calculated Concordia s were determined using the error propagation scheme of Horstwood et al. (2016). The same measurement intervals chosen for zircon dating were also applied for trace element measurements. To determine the trace element concentrations, NIST SRM610 was used as external standard to calibrate the mass spectrometer and ppm Si (according to the zircon stoichiometry) were used as internal standard. In-situ Hf isotopic composition of zircon In-situ Hf isotopic composition of zircon were determined on the same grains analysed for U-Pb data and trace element characterization (one spot per grain) on a Nu plasma MC-ICP-MS (Nu instrument Ltd) attached to a 193 nm UV ArF Excimer laser at at the Department of Earth Sciences at ETH Zurich. Ablation was performed using He as a sweep gas with flow rate of l/min and combined with Ar (0.7 l/min) using a 38 µm spot size and a 5 Hz frequency. Each ablation was preceded by a 40 s background measurement. Ablated zircons were measured for 60 s. In order to correct for isobaric interferences on 176 Hf, Lu and Yb were analyzed using 173 Yb/ 176 Yb = and 175 Lu/ 176 Lu = (Chu et al., 2002). The Hf and Yb mass bias coefficients were calculated using an exponential law from measured 179 Hf/ 177 Hf and 173 Yb/ 171 Yb, respectively, and using natural abundance reference values of 179 Hf/ 177 Hf = and 173 Yb/ 171 Yb = (Chu et al., 2002). Lu mass bias fractionation was assumed to be the same as Yb. To evaluate precision and accuracy of the data, reference zircons with well-known Hf isotopic compositions Temora-2 ( ; Black et al., 2004), Mud Tank ( ; Black and Gulson, 1978) and Plešovice ( ; Sláma et al., 2008) were systematically measured. In particular, in order to evaluate if data correction for the isobaric interference from Yb was appropriate, a Yb-rich standard (Temora) was measured and data displayed in a 176 Hf/ 177 Hf vs. 176 Yb/ 177 Hf diagram (Fig. 1). Measured Hf isotopic compositions of Temora are not correlated to 176 Yb/ 177 Hf and are close to the reference value of , indicating that the correction is appropriate. Calculations of εhf(t) and depleted mantle model (TDM) were carried out using the 176 Lu decay constant of Scherrer et al. (2001) and the 176 Lu/ 177 Hf and 176 Hf/ 177 Hf chondritic isotopic ratios of Blichert-Toft and Albarède (1997).

3 Fig. 1: 176 Hf/ 177 Hf vs. 176 Yb/ 177 Hf diagram for the analysed zircons and standard TEMORA-2 (Hf isotopic composition = ; Black et al., 2004).

4 DR2. FIELD ASPECT AND MICROPHOTOGRAPHS OF INVESTIGATED SAMPLES

5 DR3. BULK ROCK GEOCHEMISTRY FOR CARBONATITES AND MARBLES INTERCALATED WITHIN PARAGNEISSES Rock type Carbonatites Marbles within paragneiss Sample VM1 VM9 VF33 VF9 VF33B BC98 CA-01 ST-02 BC-16 Location Val Mastallone Val Fiorina La Balma Candoglia Val Strona A. Scaredi SiO2 wt% TiO2 wt% Al2O3 wt% *FeOtot wt% MnO wt% MgO wt% CaO wt% Na2O wt% K2O wt% P2O5 wt% Rb ppm Ba ppm Th ppm U ppm Ta ppm b.d.l. Nb ppm b.d.l. La ppm Ce ppm Pb ppm Pr ppm Sr ppm Nd ppm Hf ppm b.d.l. Zr ppm Sm ppm b.d.l. Eu ppm b.d.l. Gd ppm b.d.l. Tb ppm Dy ppm b.d.l. Y ppm Ho ppm Er ppm b.d.l. Tm ppm b.d.l Yb ppm b.d.l. b.d.l. Lu ppm b.d.l. b.d.l. Major elements from XRF analysis; trace elements from LA-ICP-MS analysis (see A.1) *Total iron as FeO b.d.l.: below detection limit

locations and s. DR5. INCLUSIONS IN ZIRCON Fig.

6 DR4. CATHODOLUMINESCENCE IMAGES OF CARBONATITE ZIRCONS Fig. 3: Cathodoluminescence (CL) ims of representative zircon grains from intrusive carbonatites VM and VF with spot locations and s. DR5. INCLUSIONS IN ZIRCON Fig. 4: Optical ims of selected zircons with calcite inclusions and Raman spectroscopy results on inclusions. Blue and red dotted spectra are typical spectra for zircon and calcite, respectively (from RRUFF TM database, Lafuente et al., 2015).

7 DR6. ZIRCON U-Pb-Th ISOTOPE DATA FOR ANALYSED CARBONATITES AND STANDARDS S pot Zircon morphology 206 Pb 235 U 206 P b/ 238 U 208 P b/ 232 Th E rror Corr 206 P b/ 238 U vs E rror Corr 238 U/ 20 6 P b vs 206 Pb 206 Pb 235 U 206 P b/ 238 U 208 P b/ 232 Th 235 U Carbonatite sample VM1 VM1-01* faint-zoned VM1-02* faint-zoned VM1-04* homogeneous VM1-05* faint-zoned VM1-06 faint-zoned VM1-07 homogeneous VM1-08* faint-zoned VM1-09 faint-zoned VM1-10* homogeneous VM1-12* homogeneous VM1-13* faint-zoned VM1-15* homogeneous VM1-16* homogeneous VM1-17 faint-zoned VM1-19* faint-zoned VM1-20 faint-zoned VM1-21* faint-zoned VM1-22 faint-zoned VM1-23* faint-zoned VM1-25* faint-zoned VM1-26 faint-zoned VM1-27* faint-zoned VM1-29 faint-zoned VM1-35* faint-zoned VM1-36 faint-zoned VM1-37* faint-zoned VM1-39 homogeneous VM1-40 homogeneous VM1-42* homogeneous VM1-43* homogeneous Carbonatite sample VF33 VF33-01 core/rim VF33-02* homogeneous VF33-03* homogeneous VF33-04* homogeneous VF33-05* faint-zoned VF33-06* homogeneous VF33-07* homogeneous VF33-08* homogeneous VF33-09* homogeneous VF33-10 core/rim VF33-11* faint-zoned VF33-12 faint-zoned VF33-13 core/rim VF33-14 homogeneous VF33-15 faint-zoned VF33-16 faint-zoned VF33-17* faint-zoned VF33-18* faint-zoned VF33-19 faint-zoned VF33-20 faint-zoned VF33-21 faint-zoned VF33-22* homogeneous VF33-23* faint-zoned VF33-24* faint-zoned VF33-25* faint-zoned VF33-26 core/rim VF33-27 homogeneous *points used to calculate the concordant not concordant: not considered mix between core and rim Permian oscillatory-zoned core points influenced by inclusions

8 S pot 206 Pb 235 U 206 P b/ 238 U 208 P b/ 232 Th E rror Corr 206 P b/ 238 U vs E rror Corr 238 U/ 20 6 P b vs 206 Pb 235 U 206 P b/ 238 U 208 P b/ 232 Th 235 U 206 Pb Standard GJ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Standard Plesovice Z_Plesovice_ Z_Plesovice_ Z_Plesovice_ Z_Plesovice_ Z_Plesovice_ Z_Plesovice_ Standard Z_91500_ Z_91500_ Z_91500_ Z_91500_ Z_91500_ Z_91500_ Standard AUS7 Z_AUSZ7_1_ Z_AUSZ7_1_ Z_AUSZ7_1_ Z_AUSZ7_1_ Z_AUSZ7_1_ Z_AUSZ7_1_ Standard NIST 610 G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_ G_NIST610_

DR7. ZIRCON Hf-Lu-Yb ISOTOPE DATA FOR ANALYSED CARBONATITES AND STANDARDS S pot Age (Ma ) Time (s) 17 6 Y b/ 17 7 Hf (c orr) 2 σ 17 6 Lu/ 17 7 Hf (c orr) 2 σ Hf17 8 _ 17 7 2 σ Hf F r a c t Tota l Yb

2 4.3 0.282554 0.000088 0.282554-7.7-3.6 3.5 1.2 VM1-02 187 36 0.00059 0.000262 0.0000203 0.000001 1.467283 0.000080-1.3-1.8 4.2 0.282678 0.000075 0.282678-3.3 0.8 3.1 1.0 VM1-04 187 35 0.000277 0.

282654-4.2-0.1 1.9 1.1 VM1-08 187 36 0.000822 0.000259 0.0000266 0.000001 1.46727 0.000075-1.3-2.9 4.4 0.282596 0.000074 0.282596-6.2-2.1 3.0 1.2 VM1-10 187 36 0.000721 0.000169 0.0000229 0.000001 1.467319 0.

2 VM1-13 187 36 0.000711 0.000080 0.0000249 0.000001 1.467386 0.000080-1.3-1.3 4.8 0.282585 0.000063 0.282585-6.6-2.5 2.6 1.2 VM1-15 187 36 0.000577 0.000453 0.0000145 0.000001 1.467348 0.000063-1.

9 DR7. ZIRCON Hf-Lu-Yb ISOTOPE DATA FOR ANALYSED CARBONATITES AND STANDARDS S pot Age (Ma ) Time (s) 17 6 Y b/ 17 7 Hf (c orr) 2 σ 17 6 Lu/ 17 7 Hf (c orr) 2 σ Hf17 8 _ σ Hf F r a c t Tota l Yb Fr Hf act Be a m S tdcorr 17 6 Hf/ 17 7 Hf 2 σ 17 6 Hf/ 17 7 Hf (initia l) εhf(0 ) εhf(t) 2 σ T DM Carbonatite sample VM1 VM VM VM VM VM VM VM VM VM VM VM VM VM VM VM VM VM VM VM VM Carbonatite sample VF33 VF VF VF VF VF VF VF VF VF VF VF VF VF VF VF VF VF VF VF VF VF not concordant: not considered mix between core and rim Permian oscillatory-zoned core Fig. 4: εhf(t) values of individual analyses of zircon from carbonatites. For VM1 zircons and group 1 and 2 VF33 zircons, εhf(t) has been re-calculated for the concordant inferred to represent the magmatic of carbonatite intrusion as recommended by Vervoort and Kemp (2016). For zircons composed of core and rim, εhf(t) has been re-calculated for the of the single spot analyses.

10 S pot Age (Ma ) Time (s) 17 6 Y b/ 17 7 Hf (c orr) 2 σ 17 6 Lu/ 17 7 Hf (c orr) 2 σ Hf17 8 _ σ Hf F r a c t Yb Tota l Fr Hf act Be a m S tdcorr 17 6 Hf/ 17 7 Hf 2 σ Standard GJ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Z_GJ_1_ Standard Temora Z_Temora2_ Z_Temora2_ Z_Temora2_ Z_Temora2_ Z_Temora2_ Z_Temora2_ Z_Temora2_ Z_Temora2_ Z_Temora2_ Z_Temora2_ Standard Z_91500_ Z_91500_ Z_91500_ Z_91500_ Z_91500_

11 DR8. ZIRCON TRACE ELEMENT COMPOSITION S pot Zirc on morphology Al P Ti Sr Y Z ro2 ( wt - %) La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta Th U Th/U Zr/Hf Carbonatite sample VM1 VM1-01 faint-zoned b.d.l VM1-02 faint-zoned b.d.l VM1-04 homogeneous b.d.l b.d.l b.d.l VM1-05 faint-zoned b.d.l VM1-06 faint-zoned b.d.l b.d.l VM1-07 homogeneous b.d.l b.d.l VM1-08 faint-zoned b.d.l. b.d.l VM1-09 faint-zoned VM1-10 homogeneous b.d.l VM1-12 homogeneous VM1-13 faint-zoned VM1-15 homogeneous b.d.l b.d.l VM1-16 homogeneous b.d.l VM1-17 faint-zoned VM1-19 faint-zoned b.d.l VM1-20 faint-zoned b.d.l b.d.l. b.d.l VM1-21 faint-zoned b.d.l b.d.l VM1-22 faint-zoned b.d.l VM1-23 faint-zoned b.d.l VM1-25 faint-zoned b.d.l b.d.l VM1-26 faint-zoned b.d.l b.d.l VM1-27 faint-zoned b.d.l b.d.l VM1-29 faint-zoned VM1-35 faint-zoned b.d.l VM1-36 faint-zoned VM1-37 faint-zoned b.d.l b.d.l VM1-39 homogeneous b.d.l VM1-40 homogeneous b.d.l VM1-42 homogeneous b.d.l VM1-43 homogeneous Carbonatite sample VF33 VF33-01 core/rim b.d.l. b.d.l. 2.7 b.d.l b.d.l. b.d.l. b.d.l. b.d.l b.d.l b.d.l VF33-02 homogeneous b.d.l. b.d.l. 2.2 b.d.l b.d.l. b.d.l VF33-03 homogeneous b.d.l. b.d.l. 4.0 b.d.l b.d.l b.d.l. b.d.l VF33-04 homogeneous b.d.l b.d.l b.d.l b.d.l. b.d.l VF33-05 faint-zoned b.d.l b.d.l b.d.l b.d.l VF33-06 homogeneous b.d.l. b.d.l. b.d.l. b.d.l b.d.l. b.d.l VF33-07 homogeneous b.d.l. b.d.l. 3.2 b.d.l b.d.l b.d.l. b.d.l VF33-08 homogeneous b.d.l. b.d.l. 2.1 b.d.l b.d.l. b.d.l. b.d.l. b.d.l. b.d.l b.d.l VF33-09 homogeneous b.d.l. b.d.l. b.d.l. b.d.l b.d.l. b.d.l. b.d.l. b.d.l. b.d.l. b.d.l. b.d.l. b.d.l b.d.l b.d.l b.d.l VF33-10 core/rim b.d.l. b.d.l. 3.4 b.d.l b.d.l. b.d.l. b.d.l. b.d.l. b.d.l. b.d.l VF33-11 faint-zoned b.d.l b.d.l b.d.l. b.d.l. b.d.l. b.d.l b.d.l VF33-12 faint-zoned b.d.l. b.d.l. 3.4 b.d.l b.d.l. b.d.l. b.d.l. b.d.l. b.d.l. b.d.l. b.d.l b.d.l VF33-13 core/rim b.d.l. b.d.l. 4.1 b.d.l b.d.l. b.d.l. b.d.l. b.d.l. b.d.l. b.d.l. b.d.l VF33-14 homogeneous b.d.l b.d.l b.d.l b.d.l. b.d.l b.d.l VF33-15 faint-zoned b.d.l VF33-16 faint-zoned VF33-17 faint-zoned b.d.l. b.d.l. 3.6 b.d.l b.d.l b.d.l. b.d.l b.d.l VF33-18 faint-zoned b.d.l. b.d.l. 3.0 b.d.l b.d.l b.d.l. b.d.l. b.d.l VF33-19 faint-zoned 18.8 b.d.l. 4.4 b.d.l b.d.l b.d.l. b.d.l. b.d.l. b.d.l VF33-20 faint-zoned b.d.l. b.d.l. 2.9 b.d.l b.d.l b.d.l. b.d.l. b.d.l VF33-21 faint-zoned VF33-22 homogeneous b.d.l. b.d.l b.d.l. b.d.l b.d.l VF33-23 faint-zoned b.d.l. b.d.l. 2.5 b.d.l b.d.l b.d.l. b.d.l VF33-24 faint-zoned b.d.l. b.d.l. 2.5 b.d.l b.d.l b.d.l. b.d.l. b.d.l VF33-25 faint-zoned b.d.l. b.d.l. 2.9 b.d.l b.d.l b.d.l. b.d.l b.d.l VF33-26 core/rim b.d.l. b.d.l. 4.6 b.d.l b.d.l VF33-27 homogeneous b.d.l. b.d.l. 3.4 b.d.l b.d.l b.d.l. b.d.l All concentrations except for Zr are in ppm. ZrO concentration is in wt-%. not concordant b.d.l.below detection limit mix between core and rim Permian oscillatory-zoned core points influenced by inclusions

12 DR9. XRF MAJOR ELEMENT BULK ROCK COMPOSITION OF ALKALINE INTRUSIONS FROM THE IVREA ZONE AND SERIE DEI LAGHI Rock type / Author Sample S io 2 TiO 2 Al 2 O 3 Fe 2 O 3 Fe O MnO Leucocratic enclaves within carbonatite VF this study VF this study VF this study VF16-39B this study VF this study VF16-39A this study VF this study VF Plagioclasite associated to carbonatite BC this study BC this study BC this study BC this study BC this study BC this study BC Other Plagioclasites this study FI16-B this study BA-LEU this study ALP-LEU this study VF this study VF this study VF this study RE Bertolani (1957) Montata Bertolani (1957) Massera Bertolani (1968) Q Bertolani (1968) Q Syenite associated to carbonatite BC this study BC Other syenite Stähle et al. (1990) S Stähle et al. (1990) S Stähle et al. (1990) C130a Stähle et al. (1990) C130a Stähle et al. (2001) C Stähle et al. (2001) C Stähle et al. (2001) Alkaligabbro/diorite associated to carbonatite BC this study BC this study BC Other alkaligabbro/diorite this study MB this study VF Bertolani (1954) n Gabbro associated to carbonatite VF this study VF this study VF Hornblendite cumulates associated to sample VF this study VF this study VF Other hornblendite cumulates this study ALP this study ALP-HBL this study ALP this study BC Hornblendite dykes + hornblende syenite Stähle et al. (2001) C Stähle et al. (2001) C550a Stähle et al. (2001) C Stähle et al. (2001) C Stähle et al. (2001) Stähle et al. (2001) Stähle et al. (2001) Pyroxenite enclave in sample VM this study VM this study VM this study VM this study VM this study VM this study VM 15-16B this study VM this study VM this study VM this study VM Dykes Serie dei Laghi Reinhard (1964) 10R Reinhard (1964) Reinhard (1964) Reinhard (1964) 1R Reinhard (1964) Reinhard (1964) C16 Rhd Reinhard (1964) Reinhard (1964) C Reinhard (1964) C Reinhard (1964) C Reinhard (1964) LOI: loss on ignition MgO Ca O Na 2 O K 2 O P 2 O 5 Cr 2 O 3 NiO LOI Tota l Na 2 O/ K 2 O

XM1/331 XM1/331 BLFX-3 XM1/331

XM1/331 XM1/331 BLFX-3 XM1/331 a b AkC AkC strontian fluoro-apatite clinopyroxene phlogopite K-richterite XM1/331 clinopyroxene XM1/331 Fe-Ti ox c d clinopyroxene kric AkC ilmenite Sr-barite AkC XM1/331 BLFX-3 Supplementary Figure 1.