# New constraints on the early formation of the Western Dharwar Craton (India) from igneous zircon U-Pb and Lu-Hf isotopes

Martin Guitreau, Samuel B. Mukasa, Lorne Loudin, Sajeev Krishnan

► To cite this version:

Martin Guitreau, Samuel B. Mukasa, Lorne Loudin, Sajeev Krishnan. New constraints on the early formation of the Western Dharwar Craton (India) from igneous zircon U-Pb and Lu-Hf isotopes. Precambrian Research, 2017, 302, pp.33-49. 10.1016/j.precamres.2017.09.016. hal-04432083

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# New constraints on the early formation of the Western Dharwar Craton

(India) from igneous zircon U-Pb and Lu-Hf isotopes

## Highlights:

- We present new U-Pb and Lu-Hf isotope data for igneous zircons from the WDC (75 characters)

- We found the oldest granitoid of the WDC which is a 3411 Ma peraluminous orthogneiss (85 characters)

- This orthogneiss is suggested to mark the beginning of the WDC formation (72 characters)

- Our results reveal that ancient crust up to 3607 Ma is present as inherited zircons (83 characters)

- No crust older than 3410 Ma was involved in the WDC formation prior to ~3200 Ma (79 characters)
1 New constraints on the early formation of the Western Dharwar

2 Craton (India) from igneous zircon U-Pb and Lu-Hf isotopes

3

4 Martin Guitreau¹,²,³*, Samuel B. Mukasa¹,⁴, Lorne Loudin¹,⁵, Sajeev Krishnan⁶

5

6 ¹CEPS-Department of Earth Sciences, University of New Hampshire, James Hall, 56

7 College Road, Durham, NH 03824, USA

8 ²School of Earth and Environmental Sciences, The University of Manchester,

9 Williamson building, Oxford road, Manchester, M13 9PL, UK

10 ³Université Clermont Auvergne, Laboratoire Magmas et Volcans, IRD, CNRS, UMR

11 6524, 6 avenue Blaise Pascal, 63178 Aubière, France

12 ⁴Department of Earth Sciences, University of Minnesota, Pillsbury Hall, 310 Pillsbury

13 Drive SE, Minneapolis, MN 55455, USA

14 ⁵Gemological Institute of America, Inc., 50 W 47th Street, New York, NY 10036, USA

15 ⁶Centre for Earth Sciences, Indian Institute of Science, Bangalore 560 012, India

16 * Corresponding author: martin.guitreau@uca.fr

17

18 Keywords: Western Dharwar Craton, zircon U-Pb geochronology, Lu-Hf isotope

19 system, continents, Archean

20

21 Word count: abstract = 344; Main text = 10492; Figures = 9 (+ 6 in supplementary)

22 and Tables = 4 (+6 in supplementary); refs = 124

23

24
26 The Western Dharwar Craton (WDC) is an Archean crustal segment for which
27 the earliest stages of development have remained poorly constrained because the
28 oldest identified lithologies are chronologically indistinguishable despite vastly
29 different compositions and origins (i.e., 3352 ± 110 Ma Sargur-group komatiites
30 and 3342 ± 6 Ma Hassan-Gorur TTG gneiss). Indication for older crust come from
31 ancient detrital zircons (3450-3610 Ma), although their genetic link to the WDC is
32 purely conjectural. In order to bring new understanding to early development of
33 the WDC, we studied orthogneisses around the Holenarsipur Schist Belt (HSB)
34 for their petrography, major-oxide concentrations, zircon U-Pb geochronology,
35 and Lu-Hf isotope systematics. Our results reveal that the WDC igneous record
36 contains crust older than 3350 Ma in the form of a 3410.8 ± 3.6 Ma granitic gneiss
37 and inherited zircons with ages ranging from 3295 ± 18 to 3607 ± 16 Ma that were
38 found within a 3178 ± 10 Ma trondhjemitic gneiss and a biotite-rich enclave found
39 within it. The presence of muscovite and the peraluminous signature of the
40 granitic gneiss, in spite of mildly-depleted Hf isotopic signature (εHf = +2.2 ± 0.6 at
41 3410.8 Ma), suggest that this sample formed by reworking of a felsic precursor
42 with short crustal residence time, possibly marking the beginning of WDC
43 formation. The oldest inherited zircons display variable εHf ranging from +10.4 at
44 3414 Ma to -2.3 at 3607 Ma that did not seem to have influenced the Hf isotopic
45 composition of granitoids of the WDC that formed between 3200 and 3410 Ma,
46 except perhaps in the Sargur area. We suggest that the WDC formed remote from
47 continental crust until a crustal block containing >3410 Ma zircons was accreted
48 to it ~3200 My ago. This event resulted in the stabilization of the WDC which is
49 marked by diapiric granitoids to which the 3178 Ma trondhjemitic gneiss belongs.
After 3200 Ma, the crustal block together with granitoids formed between 3410 and 3200 Ma buffered the Hf isotopic signature of newly formed granitoids, hence, indicating that, by then, the WDC already was a stable continental segment.

# 1. Introduction:

The Western Dharwar Craton (WDC; Southern India) is amongst the best-preserved pieces of Archean crust and therefore has been well studied (e.g., Naqvi and Rogers, 1987; Bouhallier et al., 1995; Chardon et al., 2008; Ramakrishnan, 2009; Dey, 2013; Jayananda et al., 2015). It has recorded multiple episodes of magmatic and volcanic activity as well as several sedimentary cycles and tectonic events that started in the Paleoarchean (~3400 Ma) and ended around the Archean-Proterozoic transition (~2500 my ago), although later metamorphic events have also occured (e.g., Naqvi and Rogers, 1987; Bhaskar Rao et al., 1992; Meen et al., 1992; Miller et al., 1996; Table 1). Despite a large number of studies, including recent ones, having addressed the question of the evolution of the Dharwar craton (e.g., Naqvi and Rogers, 1987; Chadwick et al., 2000; Jayananda et al., 2008; Lancaster et al., 2015), there still is uncertainty in the timing and the nature of WDC's first crust formation. This is because the two oldest known lithologies appear coeval within analytical uncertainty, and yet have vastly different compositions. These units are the 3352 ± 110 Ma Sargur-group komatiites (Jayananda et al., 2008) and the Hassan-Gorur gneisses, ranging from dioritic amphibolites to typical TTGs (e.g., Beckinsale et al., 1980; Bhaskar Rao et al., 1991; Naqvi et al., 2009; Jayananda et al., 2015). These orthogneisses have been dated at 3358 ± 66 Ma by Beckinsale et al., (1980), and more recently refined to 3342 ± 6 Ma by Jayananda et al. (2015). Yet, zircons from detrital metasediments (i.e., quartzites and conglomerates; Nutman et al., 1992; Lancaster et al., 2015; Bhaskar Rao et al., 2008; Sarma et al., 2012)
reveal the presence of sialic crust as old as 3542 ± 9 to 3634 ± 10 Ma in the vicinity of WDC between ~3300 My and ~2500 My ago, as deduced from the estimated age of deposition for the studied detrital sediments of the WDC (Table 1). Some of the Nd isotopic signatures displayed by Hassan-Gorur gneisses are consistent with the involvement of pre-existing crust in their genesis (Jayananda et al., 2015), but closed-system evolution of the Sm-Nd isotope system in these gneisses cannot be verified. Therefore, the actual age of the oldest generations of WDC's peninsular gneisses remains uncertain (e.g., Jayananda et al., 2008, 2015; Naqvi et al., 2009; Dey, 2013; Lancaster et al., 2015), while it bears a great deal on our understanding of the early history of the Dharwar Craton.

Zircons derived from terranes adjacent, or accreted, to a craton, after its major stages of formation, can contribute to the local detrital zircon record. Interestingly, neighboring Bastar and Bundelkhand cratons, as well as the Coorg Block, contain old gneisses dated at 3509 ± 14 Ma (Sarkar et al., 1993), 3561 ± 11 Ma (Ghosh, 2004), 3582.6 ± 4 Ma (Rajesh et al., 2009), 3550.9 ± 5.9 Ma (Kaur et al., 2014), and 3502 ± 11 Ma (Santosh et al., 2016). Rare ancient zircon cores have also been found in TTG gneisses from the Karwar Block (3473-3601 Ma; Ishwar-Kumar et al., 2013). However, while WDC's oldest detrital zircons show coherent Hf isotopic signatures (see Sarma et al., 2012; Lancaster et al., 2015), they generally differ from those of their coeval igneous counterparts from Coorg Block and Bundelkhand Craton's oldest gneiss (Santosh et al., 2016; Kaur et al., 2014), possibly indicating a different origin. Quartzites and greywackes in which Paleoarchean detrital zircons have been found, are assumed to have been deposited at respective ages of ~3300-3200, ~2900 Ma, and ~2500 Ma (e.g., Nutman et al., 1992; Bhaskar Rao et al., 1992, 2008; Peucat et al., 1995; Sarma et al., 2012; Hokada et al., 2013; Table 1). Therefore, it remains uncertain
100 if the ages indicated by detrital zircons accurately depict the age of the oldest crusts
101 involved in development of the WDC.

102 To shed new light on the context of early formation of the Western Dharwar
103 Craton, we have conducted a field survey of some of the oldest generations of
104 peninsular gneisses in the Hassan-Gorur area. Here, we report on two felsic gneisses
105 and an enclave found within one of them, as well as on their zircon U-Pb ages and Hf
106 isotopic signatures. Our new results considered with available data on the WDC bring
107 important constraints on the early development of the WDC.

108

109 **2. Geological background**

110 The Dharwar craton (Southern India) is subdivided into a western (WDC) and an
111 eastern (EDC) part that are separated by a major shear zone along the Chitradurga
112 greenstone belt ("Ch" in Fig. 1), and a N-S trending intrusion composed of late Archean
113 K-rich granites (i.e., Closepet batholith; e.g., Moyen et al., 2003; Fig. 1). Most of the
114 rocks of the EDC exhibit Neoarchean ages, whereas those found in the WDC have
115 protoliths dated at ~2500 and up to ~3360 Ma (e.g., Beckinsale et al., 1980; Naqvi and
116 Rogers, 1987; Meen et al., 1992; Bhaskar Rao et al., 1992; Jayananda et al., 2008, 2015;
117 Sarma et al., 2012; Dey, 2013). The Dharwar craton had been northwardly tilted,
118 probably sometime between 2400 and 1600 Ma (Ramakrishnan, 2009), and therefore
119 displays an almost entire conformable crustal sequence characterized by a continuous
120 increase in metamorphic grade from greenschist to granulite toward South (e.g.,
121 Pichamuthu, 1965; Rollinson et al., 1981; Hansen et al., 1985; Raase et al., 1986).
122 Tonalite-trondhjemite-granodiorite (TTG) gneisses, locally named peninsular gneisses,
123 make up the basement of the WDC and dominantly crop out in the southern regions
124 (Fig. 1). These orthogneisses are intercalated with highly deformed supracrustal
sequences of the ~3.4-3.0 Ga Sargur group (e.g., Naqvi and Rogers, 1987; Yoshida et al., 1994; Jayananda et al., 2008, 2015) that were equilibrated in high-metamorphic grade in the late-Archean (i.e., ~8kbar and ~700-750°C around 2430 Ma; Janardhan et al., 1982; Raith et al., 1983; Jayananda et al., 2013). Both the Peninsular gneisses and the Sargur group are unconformably overlain by the 2.9-2.5 Ga Dharwar supergroup (Table 1), which is less deformed and less metamorphosed than the Sargur group. Therefore, the oldest remnants are located in the South, in high-grade metamorphic conditions, and the youngest, less metamorphosed greenstones, are located in northern regions of the WDC (Fig. 1). Some younger granites (2700-2500 Ma) are also found throughout the WDC (e.g., Taylor et al., 1984; Meen et al., 1992). The general dome-and-basin structure exhibited by the WDC have been documented in several studies that concluded that denser greenstone belts sunk into the basement gneisses by sagduction (e.g., Bouhallier et al., 1993, 1995; Chardon et al., 1996, 1998).

Supracrustal (greenstone) belts are very abundant in the WDC and they contain either one or both volcano-sedimentary groups (e.g. Hokada et al., 2013); the Sargur group (~3350-3000 Ga) and the Dharwar supergroup (2900-2500 Ga), the latter of which is further sub-divided into Chitradurga (upper section) and Bababudan groups (lower section) based on lithologies and ages (e.g., Naqvi and Rogers, 1987; Ramakrishnan, 2009; Table 1). Sargur Group volcanic sequences are dominated by komatiites and tholeiitic basalts, with subordinate felsic lava flows, whereas the Dharwar Supergroup volcanics contain abundant tholeiitic to felsic volcanics with subordinate komatiitic basalts. Sediments composing Sargur and Dharwar groups are conglomerate, quartzite, pelite, carbonate, and banded iron formation. According to Ramakrishnan (2009), the Sargur Group occurs in two types of lithological association, namely: (i) linear ultramafic-mafic belts containing subordinate clastic sediments and
BIF (e.g. Nuggihalli, Nagamangala and Krishnarajpet), and (ii) scattered ultramafic-mafic enclaves associated with quartzite-carbonate-pelite-BIF assemblage (e.g. Sargur and Mercara). The same author, together with Chadwick et al. (1989), indicates that the Dharwar sequence consists of three lithological packages that are, in the ascending order, (1) a basal quartz-pebble conglomerate with amygdular metabasalt alternations, local felsic volcanics, and banded-iron formation (BIF), which correspond to the Bababudan Group, (2a) a polymict conglomerate, quartzite, pelite, carbonate, and Mn/Fe formations that define the Vanivilas Subgroup of the Chitradurga Group, (2b) pillowed metabasalts, felsic volcanics, and BIF which form the Ingaldhal Subgroup of the Chitradurga Group, and (3) a greywacke turbidite, a polymict conglomerate, and a BIF horizon that correspond to the Ranibennur Subgroup of the Chitradurga Group.

The peninsular gneisses exhibit ages from 3360 to 3000 Ma and are somewhat heterogeneous in age and composition (e.g., Beckinsale et al., 1980; Rogers et al., 1986; Bhaskar Rao et al., 1991; Jayananda et al., 2015). Multiple generations of peninsular gneisses have been identified and classified using different criteria (e.g., Janardhan et al., 1978; Bhaskar Rao et al., 1983; Naqvi et al., 1983; Monrad, 1983) but the most commonly used classification has been that of Monrad (1983), which is mainly based on geochemistry. The latter author, through the example of the Hassan District (Karnataka), proposed a low-Rb group (~3360-3200 Ma), a low-Al group (~3200-3100 Ma), a high-Al group (~3000 Ma) and a post-tectonic group (~3000-2900 Ma) corresponding to massive diapiric bodies (e.g., Halekote trondhjemite, Chikmagalur granite; Stroh et al., 1983; Taylor et al., 1984; Meen et al., 1992). A recent study (i.e., Jayananda et al., 2015) refined the classification of peninsular gneisses around the Hassan district as follows: older TTG gneisses, which contain a low-Al and high-Al group (3340-3280 Ma), younger trondhjemites, including Halekote-type, (3230-3200
Ma), eastern gneisses (3100 Ma) and the Chikmagalur granite (3150 Ma). The older TTG gneisses have chemical characteristics suggesting that they formed by partial melting of essentially undepleted heterogeneous mafic crusts at shallow depth and high pressure, for the low-Al and high-Al group, respectively. In addition, older TTG gneisses indicate possible interaction with pre-existing crust during emplacement. Similar mafic sources can account for the formation of the trondhjemites (e.g., Halekote-type) with significant interaction with pre-existing crust as testified to by the presence of inherited zircon cores (e.g., Jayananda et al., 2015). The eastern gneisses more likely represent shallow level melting of depleted mafic sources subsequently contaminated by older TTG gneisses (low-Al type), whereas the Chikmagalur granite most likely originate from partial melting of newly formed TTG crust at lower crustal level.

In a craton-wide compilation of available Nd isotope data, Dey, (2013) proposed that the WDC formed through essentially juvenile addition (mafic and felsic) between 3360 and 3000 Ma ($ε_{Nd}$ = +1.5 to +6.4), followed by dominantly mafic crust addition between 2900 and 2600 Ga ($ε_{Nd}$ = -0.3 to +0.4), and major crust reworking at 2600-2500 Ma, accompanied by minor juvenile input. A recent study dealing with detrital zircon U-Pb and Lu-Hf isotope systematics (Lancaster et al., 2015) concluded that there had been significant juvenile crust extraction from ~3.3. to 2.7 Ga and cratonization at ~3.0 Ga in the WDC. These authors also suggested continuous extraction of mantle melts from as far back as 3.7 Ga to 3.3 Ga, which matches ages of some detrital zircons (Table 1 and references therein) but are mostly absent from the igneous record.

### 3. Sampling strategy and sample description
Samples analyzed in this study were collected in two separate locations around the Holenarsipur Schist Belt (HSB; Fig. 2; Table 2) because this area hosts WDC's oldest peninsular gneisses reported so far (e.g., Beckinsale et al., 1980; Bhaskar Rao et al., 1991; Meen et al., 1992; Jayananda et al., 2015). The HSB area consists of volcanosedimentary successions that mostly belong to the Sargur group (e.g., Peucat et al., 1995; Jayananda et al., 2008) and that sunk by sagduction into 3350-3300 Ma peninsular gneisses (e.g., Beckinsale et al., 1980; Bouhallier et al., 1993; Jayananda et al., 2015). Both peninsular gneisses and the HSB were intruded by Halekote trondhjemites ~3200 My ago (e.g., Taylor et al., 1984; Jayananda et al., 2015). Most of the gneisses analyzed in previous studies were collected in quarries (e.g., Beckinsale et al., 1980; Bhaskar Rao et al., 1991; Jayananda et al., 2015), hence possibly missing the oldest generations of peninsular gneisses. Consequently, we have purposely sampled gneisses both inside, and outside quarries where, however, outcrops are limited. Nevertheless, we made every effort to collect fresh samples, free of any altered surfaces.

214

## 3.1. Field occurrence of orthogneiss 13DC12

Sample 13DC12 is a fine-grained and massive to very weakly foliated brownish orthogneiss collected from meter- to decimeter-scale outcrops protruding from weathered soils (Fig. 3A). Medium-grained pegmatite veins, which belong to only one identifiable generation, crosscut the orthogneiss (Fig. 3A), but these were avoided in collecting sample 13DC12. As summarized in Table 2, this sample is composed dominantly of quartz, plagioclase, K-Feldspar (microcline), but also contains biotite, muscovite, and very few opaque phases (e.g., oxide, sulfide). At the hand-sample scale some rare 1-5 mm octahedral metallic phases are also visible. In thin section (see Figs.

216

217

218

219

220

221

222

223
224 **3B and 3C**), quartz consists of medium-sized to large xenomorphs that sometimes contain smaller euhedral to subhedral quartz grains, likely recrystallized statically.
225
226 Plagioclase often appears as medium to large sub-euhedral to xenomorphic crystals
227 showing variable degrees of sericitization. K-Feldspar is commonly found as small
228 xenomorphs intercalated between larger quartz or plagioclase grains, although big
229 crystals can sometimes be found. Biotite is always present as small subhedral crystals,
230 often altered into chlorite. In places, zircon is visible within biotite because of the halo
231 generated through radioactive decay of zircon-hosted U and Th. Muscovite forms
232 bigger crystals than biotite and they are often subhedral. Although the rock appears
233 massive to weakly foliated, and displays a granoblastic texture (Figs. 3B and 3C), bands
234 of grain-size reduction down to a factor of ~5, are visible at the thin section scale.
235 However, no noticeable change in mineralogy is observed in these bands.
236

236

237 **3.2. Field occurrence of orthogneiss 13DC13**

238 Sample 13DC13 is a fresh, grey, and fine-grained orthogneiss (Fig. 3D), that is massive
239 to weakly foliated. In contrast to the field occurrence of orthogneiss 13DC12, this
240 sample was collected in a large (~500 x 500 m) active quarry (Fig. 3D; Table 2)
241 throughout which the outcrops are homogeneous. It is, nevertheless, crosscut by
242 multiple generations of pegmatite veins of various sizes and spatial distribution (Fig.
243 3D), and some biotite-rich enclaves ranging in size from ~5 x 2 to ~30 x 10 cm can also
244 be found sparsely distributed within it. Sample 13DC13 is composed essentially of
245 plagioclase, quartz, K-Feldspar (microcline), biotite, and muscovite (Table 2). In thin
246 section (see Figs. 3E and 3F), quartz appears as medium-sized and relatively fresh
247 xenomorphs. Plagioclase show little sericitization and also occurs as subhedral crystals
248 to xenomorphs of substantial size, in contrast to K-Feldspar which is commonly small

238

239

240

241

242

243

244

245

246

247

248
249 with the exception of some rare large and fresh xenomorphs that are likely secondary.
250 Biotite is more abundant than in the orthogneiss 13DC12 and crystals are usually
251 subhedral and fresh (no or very little alteration into chlorite). Zircon halos are visible
252 in some biotite crystals. Muscovite is slightly less abundant than biotite but has a similar
253 habitus and size. Both biotite and muscovite seem to have been co-genetically
254 crystallized as they form coherent masses of interspersed crystals. Almost no opaque
255 phase can be seen in thin section. Sample 13DC13 is characterized by a granoblastic
256 texture visible in thin section (Figs. 3E and 3F).

257
258 **3.3. Biotite-rich enclave (13DC15)**

259 Sample 13DC15 is a fresh ~20 x 10 cm biotite-rich enclave found in the orthogneiss
260 that 13DC13 represents. Due to its high-biotite content, this type of enclave is very
261 often deeply weathered and friable but the ongoing work in the quarry exhumed some
262 fresh samples such as 13DC15. This rock contains approximately 70% biotite
263 (sometimes turned into chlorite), 10% quartz, 10% plagioclase, and 10% of various
264 minerals (e.g., K-Feldspar, muscovite, opaque phases; Table 2).

265
266 **4. Analytical details**

267 **4.1. Major and minor element analysis**

268 Major- and minor-oxide results are given in Table S1. Measurements were done by
269 ICP-AES (Jobin-Yvon ULTIMA C) at the Laboratoire Magmas et Volcans (Clermont-
270 Ferrand, France). The rock standard BHVO-1 was also analyzed so as to determine the
271 precision and accuracy of the measurements. Major- and minor-oxide concentrations
272 were within <1% up to 5% of consensus values (Flanagan, 1976; Abbey, 1983;
273 Govindaraju, 1994) whereas analytical precisions were better than 1% for both major
274 and minor oxides, except for P₂O₅ concentration which had 3% uncertainty.

275

276 **4.2. Zircon U-Pb geochronology by LA-ICP-MS**

277 Zircon crystals were separated at the University of Colorado (Boulder, CO, USA) using
278 standard mineral separation techniques (see Mojzsis et al., 2003). The most optically
279 clear zircon grains devoid of cracks and inclusions were selected and mounted in epoxy
280 together with fragments of the zircon standards AS3 (1099.1 ± 0.5 Ma; Paces and
281 Miller, 1993) and 91500 (1065.4 ± 0.3 Ma; Wiedenbeck et al., 1995). The selected
282 crystals were euhedral to subhedral, pale pink to orange, and transparent to slightly
283 cloudy. The spots analyzed on each grain were selected based on internal textures as
284 revealed by cathodoluminescence (CL) images acquired at the University of New
285 Hampshire using a Tescan Lyra 3 scanning electron microscope.

286 Zircon U-Pb analyses were carried out by LA-ICP-MS at the University of New
287 Hampshire (UNH). Details regarding operating conditions are given in **Table S2** and
288 results can be found in **Table 3**, and the supplementary Tables S3 and S4. A gold trap
289 was used to lower <sup>204</sup>Hg interferences on <sup>204</sup>Pb and, hence, more accurately detect the
290 presence of common Pb. Measurements were started ~5s after the beginning of the
291 ablation to allow a steady flow of the aerosol from the laser to the mass spectrometer.
292 Time-resolved signals were carefully monitored throughout each and every analysis to
293 ensure optimization and data reproducibility. Further, because of down-hole
294 fractionation, we used the t<sub>0</sub> intercept method based on data regression through linearly
295 shifting isotopic ratios as a function of time (see Košler and Sylvester, 2003; Fisher et
296 al., 2010). Both <sup>207</sup>Pb/<sup>235</sup>U and <sup>206</sup>Pb/<sup>238</sup>U ratios were measured, but the former was
297 only used as a quality check by comparing it to <sup>207</sup>Pb/<sup>235</sup>U calculated from measured
$^{206}$Pb/$^{238}$U and $^{207}$Pb/$^{206}$Pb, as well as a $^{238}$U/$^{235}$U of 137.88. Decay constant used are the followings: $^{238}\lambda$ = 1.55125·10⁻¹⁰, $^{235}\lambda$ = 9.8485·10⁻¹⁰ (Jaffey et al., 1971), and $^{232}\lambda$ = 4.9475·10⁻¹¹ (Le Roux and Glendenin, 1963). $^{207}$Pb/$^{206}$Pb ages were calculated using iterative convergence. The ISOPLOT program (Ludwig, 2008) was used to display the processed data on Concordia diagrams and to determine the sample ages. We further measured semi-quantitative (no internal standardization) concentrations of Pb, U, and Th, by using AS3 as an external standard (Paces and Miller, 1993). Finally, $^{232}$Th/$^{238}$U ratios were calculated from $^{208}$Pb/$^{206}$Pb values and determined $^{207}$Pb/$^{206}$Pb ages.

91500 zircon standard was analyzed as an unknown throughout the session for quality check. The weighted average $^{207}$Pb/$^{206}$Pb and upper-intercept U-Pb age obtained for 91500, over the course of this study, were both 1061.6 ± 7.1 Ma (2σ; n = 10; Fig. S1). These ages agree well within uncertainty with the commonly accepted ID-TIMS age of 1065.4 ± 0.3 Ma (Wiedenbeck et al., 1995). 91500 zircon standard Pb, U, and Th mean concentrations determined over the course of this study gave 14.4 ± 2.1 (2σ; n = 10), 66.3 ± 7.9, and 23.0 ± 4.5 ppm (Table S3), respectively. These values are in reasonably good agreement with the respective recommended values of 15 ± 4 (2σ), 80 ± 16, and 29.9 ± 4.2 ppm (Wiedenbeck et al., 2004), which are means of analyses performed in 5 different laboratories. The mean calculated $^{232}$Th/$^{238}$U obtained for 91500 was 0.37 ± 0.01 (2σ; n = 10; Table S3), which is in agreement with values of 0.3444 ± 0.0018 (2σ), determined by Wiedenbeck et al. (1995) on 2 zircon fragments, and 0.38 ± 0.09 determined by numerous LA-ICP-MS analyses (Wiedenbeck et al., 2004).

320

321

## 4.3. Zircon Lu-Hf isotope analysis by LA-MC-ICP-MS
Lu-Hf isotope analyses were done by LA-MC-ICP-MS at Laboratoire Magmas et Volcans (LMV), Clermont-Ferrand (France). Details regarding the operating conditions are given in Table S2 and results can be found in Tables 3, S5, and S6. Lu-Hf isotope measurements were done using the cup configuration recommended by Fisher et al. (2014a). The Yb and Hf instrumental mass biases used to correct data were determined using 173Yb/171Yb normalized to the value of 1.132685 (Chu et al., 2002) and 179Hf/177Hf normalized to the value of 0.7325 (Stevenson and Patchett 1990). It was further assumed that Lu fractionation followed that of Yb (Fisher et al., 2014a). A value of 0.79618 for 176Yb/173Yb (Chu et al., 2002) and 0.02655 for 176Lu/175Lu (Fisher et al., 2014a) were used to correct data for the isobaric interferences of 176Yb and 176Lu on 176Hf. In order to monitor instrumental fractionation and data quality, zircon standards 91500, MudTank, Plešovice, and R33 were measured multiple times over the course of the LA-MC-ICP-MS analyses. Lu-Hf isotope analyses were done on top of the pits developed by ablation during the U-Pb isotope analyses in order to acquire linked information. Much like for U-Pb isotope analyses, time-resolved signals were carefully monitored throughout each and every analysis. The 176Lu decay constant of Scherer et al. (2011) and Söderlund et al. (2004), which is 1.867.10⁻¹¹, was used to calculate initial Hf isotopic compositions. Uncertainties associated with the radiogenic-ingrowth correction were propagated using the algorithms of Ickert (2013). Epsilon notations were derived from normalization to the Bulk Silicate Earth (BSE) Lu-Hf isotopic parameters published by Iizuka et al. (2015).

Obtained mean 176Hf/177Hf for 91500, MudTank, Plešovice, and R33 were 0.282299 ± 0.000018 (2σ; n=16), 0.282501 ± 0.000017 (2σ; n=17), 0.282472 ± 0.000013 (2σ; n=7), and 0.282757 ± 0.000039 (2σ; n=9), respectively (Table S5; Fig. S2). These values are well within uncertainty of the accepted values of 0.282308 ±
347 0.000006 (Blichert-Toft, 2008) for 91500, 0.282507 ± 0.000006 (Woodhead and Hergt, 2005) for MudTank, 0.282482 ± 0.000012 (Sláma et al., 2008) for Plešovice, and 348 0.282764 ± 0.000014 (Fisher et al., 2014b) for R33. Determined ¹⁷⁶Yb/¹⁷⁷Hf and 349 ¹⁷⁶Lu/¹⁷⁷Hf for these zircon standards also comply well with those recommended by 350 other authors (Table S5; e.g., Fisher et al., 2014a, 2014b).

352

353 **5. Results**

354 **5.1. Orthogneiss 13DC12 composition and ages**

355 This sample is characterized by high silica content (74 wt%), moderately high Al₂O₃ 356 (13.9 wt%), similar Na₂O and K₂O contents (3.9 and 4.3 wt%, respectively), and low 357 Fe₂O₃ (1.47 wt%), CaO (0.95 wt%), MgO (0.19 wt%), TiO₂ (0.11 wt%), P₂O₅ (0.11 358 wt%), and MnO (0.02 wt%) (Table S1). On an Ab-An-Or normative plot (O'Connor, 1965; Barker, 1979), sample 13DC12 falls in the granite field (Fig. 4A). Major elements 359 further indicate that sample 13DC12 has a peraluminous character (A/CNK and A/NK 360 > 1; Table S1; Fig. 4B). In addition, it can be seen in Figure 4C that 13DC12 plots at 361 the high-silica end of the domain that characterizes calc-alkalic rock suites, more 362 specifically in the field of Bt- and two-mica granites and on the edge of the field for 363 TTG. Similarly, in the ternary diagram proposed by Laurent et al. (2014) for 364 classification of Archean granitoids, 13DC12 falls in a zone where the fields for Bt- 365 and two-mica granites and hybrid granites overlap (Fig. 4D). Finally, Figure 4E shows 366 that 13DC13 major element concentrations comply with those of melts produced by 367 partial melting of tonalites. 368

369 Zircons recovered from this sample have similar habits but exhibit variable 370 internal structures, as revealed by CL images, ranging from simple oscillatory zoning 371 to patchy and/or chaotic domains resembling alteration/recrystallization textures (Fig.
372 **S3**). This is in line with the U-Pb data being concordant to highly discordant. Similarly, 373 U and Th concentrations vary from relatively low (<300 ppm for U and <100 ppm for 374 Th; Tables 3 and S4) to high (>1000 ppm; Tables 3 and S4) and positively correlate 375 with degrees of discordance with a change of slope beyond ~1000 ppm U. Measured 376 $^{207}$Pb/$^{206}$Pb ages do not show any correlation with discordance in the range 0-40% 377 where they vary between 3310 ± 15 and 3425 ± 18 Ma (Table 3 and S4), but steadily 378 decrease from 3235 ± 14 to 2696 ± 11 Ma between 40 and 71% discordance. The only 379 truly concordant data correspond to two analyses done on the crystal labelled 380 "13DC12_5" which gave ages of 3413 ± 7 and 3410 ± 4 Ma. The oldest $^{207}$Pb/$^{206}$Pb 381 ages determined on 13DC12's zircon population are in excellent agreement with the 382 age of this concordant zircon. When used together these ages define an upper intercept 383 age and weighted average $^{207}$Pb/$^{206}$Pb age of 3410.8 ± 3.6 and 3408.6 ± 3.6 Ma, 384 respectively (Fig. 6). All other zircons taken together, define a single broad Discordia 385 with upper- and lower-intercepts at 3440 ± 39 and 576 ± 90, respectively (Fig. 6C). 386 Note that the upper-intercept age is consistent, within uncertainty, with that determined 387 from oldest and least discordant zircons. No global correlation is observed between 388 Th/U ratios, which for the vast majority fall within the common range of magmatic 389 zircons (e.g., Wang et al., 2011; Kirkland et al., 2015), and other chemical nor isotopic 390 parameters. None of the observed internal structures indicate the presence of 391 xenocrystic cores, nor of overgrowths (Fig. S3).

392 Zircons from the granitic gneiss exhibit high $^{176}$Yb/$^{177}$Hf and $^{176}$Lu/$^{177}$Hf values 393 that are strongly correlated with each other (Table S6). Also, both ratios correlate 394 positively with the measured $^{176}$Hf/$^{177}$Hf values, which vary between 0.280685 ± 395 0.000032 and 0.281124 ± 0.000029. This correlation almost vanishes when $^{176}$Yb/$^{177}$Hf 396 and $^{176}$Lu/$^{177}$Hf are plotted against initial $^{176}$Hf/$^{177}$Hf (calculated using determined
207Pb/206Pb ages) because these latter all agree within error-bars except for two data points which exhibit the most radiogenic 176Hf/177Hf (Tables 3 and S4; Fig. 5). These two errant data points resulted from analyses done on two separate crystals (zircons #1 and #2) that exhibit advanced discordance (Tables 3 and S4) and that have been analyzed twice. The other analyses done on these crystals show initial Hf isotopic compositions that comply well with the general Hf isotope initials, especially with those determined on the concordant zircon 13DC12_5 (i.e., 176Hf/177Hf = 0.280635 ± 0.000018 and 0.280625 ± 0.000015). If all initial 176Hf/177Hf are calculated at the age given by the concordant crystal, the positive correlation between 176Yb/177Hf and 176Hf/177Hf, as well as between 176Lu/177Hf and 176Hf/177Hf completely vanishes. Broad positive correlations are observed between U concentration and 176Lu/177Hf, and therefore 176Yb/177Hf.

409

## 5.2. Orthogneiss 13DC13 composition and ages

This sample has high SiO₂ content (72.6 wt%), high Al₂O₃ (15 wt%), relatively high Na₂O (4.9 wt%) and CaO (1.82 wt%), moderately low K₂O (2.5 wt%) and Fe₂O₃ (1.69 wt%), and low MgO (0.50 wt%), TiO₂ (0.27 wt%), P₂O₅ (0.08 wt%), and MnO (0.02 wt%) (Table S1). On an Ab-An-Or normative plot (O’Connor, 1965; Barker, 1979), sample 13DC13 falls in the trondhjemite field (Fig. 4). Major elements further indicate that sample 13DC13 has a peraluminous character, much like 13DC12 (A/CNK and A/NK > 1; Table S1). Figure 4C shows that 13DC13 plots at the high-silica end of the domain that characterizes calc-alkalic rock suites, where the field for TTG and Bt- and two-mica granites overlap. Similarly, in the ternary diagram proposed by Laurent et al. (2014) for the classification of late-Archean granitoids (Fig. 4D), 13DC13 plots where the fields for Bt- and two-mica granites, hybrid granites, and TTG overlap. Finally, in

397

398

399

400

401

402

403

404

405

406

407

408

409

410

411

412

413

414

415

416

417

418

419

420

421
Figure 4E 13DC13 fall in the compositional range of melts produced by partial melting of tonalities but near the boundary with low-K and high-K mafic rocks.

Zircons from this sample show variable crystal habits from stubby to elongated, and exhibit very different types of internal structures as revealed by CL images (Fig. S4). For example, zircon #5 exhibits a concentrically zoned dark and bright core with sinuous outlines surrounded by an oscillatory-zoned outer part. Zircon #11 has a homogeneous and barely zoned core surrounded by a darker and more chaotic outer rim. In this zircon, part of the core seems to have been resorbed and replaced by the same zircon material as that forming the outer rim. Similar to 13DC12 zircons, those from 13DC13 universally show a correlation between degrees of discordance and U, as well as Th, contents, which respectively vary from a few hundred to a few thousand ppm, and from a few tens to a few hundred ppm (Tables 3 and S4). Measured $^{207}$Pb/$^{206}$Pb ages vary between 3441 ± 16 (5% discordant) and 2836 ± 20 Ma (80% discordant) (Fig. 7), and a broad correlation is observed between degrees of discordance and $^{207}$Pb/$^{206}$Pb ages. Zircons from sample 13DC13 do not define a single Discordia but instead a funnel-shaped discordance pattern on a Concordia plot with upper-intercept ages ranging from ~3100 to ~3450 Ma (Fig. S5).

Zircons from the trondhjemitic gneiss with Th/U below 0.2 yield dates from 3355 down to 2964 Ma, whereas zircons with Th/U values that characterize the common magmatic range (>0.2-0.8; e.g., Wang et al., 2011; Kirkland et al., 2015) exhibit less variability and older dates (~3450-3320 Ma). Finally, zircons with Th/U >1 exhibit younger dates of 3278-2836 Ma (Tables 3 and S4; Fig.S5).

Determined $^{176}$Lu/$^{177}$Hf and $^{176}$Yb/$^{177}$Hf for zircons from the trondhjemitic gneiss are moderately low (Tables 3 and S6; Fig. 7) and strongly correlated with each
446 other. Initial Hf isotope ratios show modest variability between 0.280717 ± 0.000022
447 and 0.280860 ± 0.000016 and do not correlate with any elemental or isotopic parameter.

448

449 **5.3. Biotite-rich enclave (13DC15)**

450 Only two zircons have been recovered from the biotite-rich enclave 13DC15 and they
451 both show simple oscillatory zoning in CL images (Fig. S6). Each zircon has been dated
452 twice (see Tables 3 and S4 and Fig. S6). The first zircon (i.e., 13DC15_1) gave
453 $^{207}$Pb/$^{206}$Pb ages of 3473 ± 21 Ma (2% discordant) and 2973 ± 30 Ma (23% discordant).
454 $^{176}$Yb/$^{177}$Hf and $^{176}$Lu/$^{177}$Hf determined on the same crystal are both low and close to
455 each other (Tables 3 and S5). In contrast to the differences exhibited by U-Pb ages, the
456 two measured $^{176}$Hf/$^{177}$Hf are in excellent agreement within uncertainty, which is also
457 the case for the initial ratios (i.e., 0.280477 ± 0.000022 and 0.280487 ± 0.000013;
458 Tables 3 and S6; Fig. 8).

459 The two U-Pb analyses performed on the second zircon crystal are very
460 consistent with each other and gave respective $^{207}$Pb/$^{206}$Pb ages of 3603 ± 23 Ma (9%
461 discordant) and 3610 ± 23 Ma (11% discordant). Determined $^{176}$Yb/$^{177}$Hf and
462 $^{176}$Lu/$^{177}$Hf are both low and close to each other (Tables 3 and S6), and the two
463 measured $^{176}$Hf/$^{177}$Hf are in excellent agreement within uncertainty, which is also the
464 case for the initial ratios (i.e., 0.280374 ± 0.000019 and 0.280373 ± 0.000021; Tables
465 3 and S6; Fig. 8).

466 The oldest ages, obtained for 13DC15_1a, 2a, and 2b, are associated with Th/U
467 ratios in the common magmatic range, whereas the significantly discordant data of
468 13DC15_1b, which indicates a $^{207}$Pb/$^{206}$Pb age of 2973 Ma, is coupled to a Th/U below
469 0.2 (Tables 3 and S6).

470
471 **6. Discussion**

472 **6.1. Origin of studied orthogneisses based on petrographic observations and**

473 **geochemical data**

474 **6.1.1. Granitic gneiss (13DC12)**

475 One of the most notable petrographic observation that one can make in 13DC12 is the

476 presence of significant amounts of muscovite which is a strong indicator for the crustal

477 origin of granites (e.g., Barbarin, 1999). This is reinforced by the peraluminous flavor

478 of this sample (Fig. 4B) together with the fact that it plots in the field of crustally-

479 derived granites (i.e., Bt- and two-mica granites) in some key geochemical diagrams

480 for late-Archean granitoids (Figs 4C and 4D). Finally, the major element composition

481 of 13DC12 matches well with that of melts expected from partial melting of tonalitic

482 sources with possible involvement of metasediments (Figs 4E). Taken altogether, we

483 consider that petrographic and geochemical observations point to a dominant crustal

484 origin for the protolith of the granitic gneiss 13DC12.

485

486 **6.1.2. Trondhjemitic gneiss (13DC13)**

487 The sample 13DC13 also contains significant amounts of muscovite that points to a

488 crustal contribution to the formation of 13DC13 protolith. This is consistent with the

489 peraluminous signature of this sample (Fig. 4B) together with the fact that it plots in

490 the field of crustally-derived granites (i.e., Bt- and two-mica granites) and hybrid

491 granites in some key geochemical diagrams for late-Archean granitoids (Figs 4C and

492 4D). Much as for 13DC12, the major element content in 13DC13 matches well with

493 that of melts expected from partial melting of tonalitic sources with probable

494 involvement of mafic sources (low-K and/or high-K; Figs 4E). Consequently, we
interpret petrographic and geochemical observations made on the trondhjemitic gneiss 495
13DC13 as evidence for its dominant crustal origin. 496

497

## 6.2. Interpretation of the zircon U-Pb ages and primary Hf isotopic signatures

### 6.2.1. Granitic gneiss (13DC12)

As illustrated in Figure 5, zircons from granitic gneiss sample 13DC12 display large variations in $^{207}$Pb/$^{206}$Pb ages, but only a small variation in initial $^{176}$Hf/$^{177}$Hf. This behavior is quite common in old zircons (e.g., Patchett, 1983; Gerdes and Zeh, 2009; Guitreau et al., 2012) and can be attributed to different sensitivities to perturbation of the U-Pb and Lu-Hf isotope systems by thermal means and/or fluid activity (e.g., Lenting et al., 2010). Because all data points, except for 13DC12_1a, comply with the closed-system evolution model for the Lu-Hf isotope system in the analyzed crystals – based on the measured $^{176}$Lu/$^{177}$Hf (Figure 5) – the observed variability in initial $^{176}$Hf/$^{177}$Hf is not considered to be geological. Rather, this variability is the result of under-correction of radiogenic $^{176}$Hf ingrowth that merely derives from the use of $^{207}$Pb/$^{206}$Pb ages that are younger than the actual crystallization ages. Zircons from the granitic gneiss, therefore, form a single population. The age of 3410.8 ± 3.6 Ma (Fig. 6A) determined using the most concordant, and oldest least discordant zircons, is hence interpreted to be the actual crystallization age of this zircon population, and by extension that of 13DC12. Figure 5 shows that zircons used to establish this age also provide very consistent initial $^{176}$Hf/$^{177}$Hf of 0.280631 ± 0.000018, which translates into an $\epsilon_{Hf}$ of +2.2 ± 0.6 at 3410.8 Ma (Table 4), and that we interpret as best reflecting the Lu-Hf isotope systematic of sample 13DC12. The upper-intercept age obtained from zircons that underwent post-crystallization U-Pb disturbance (i.e., 3440 ± 39 Ma) (Fig. 6C) is in agreement, within uncertainty, with the established crystallization age for
520 13DC12, reinforcing the notion that there is a single zircon population in the granitic gneiss. Finally, the lower-intercept age of 576 ± 90 Ma (Fig. 6C) that is interpreted as the timing of Pb-loss in some of 13DC12 zircons, matches well with metamorphic episodes recorded by rocks of the WDC and the southern granulite province (e.g., Bhaskar Rao et al., 1992; Miller et al., 1996; Meißner et al., 2002; Santosh et al., 2006).
521
522
523
524 This date corresponds to widespread Pan-African metamorphic events in the southern continents which previously comprised the supercontinent Gondwana (e.g., Yoshida et al., 1996; Meert, 2003; Santosh et al., 2005, 2006; Sato et al., 2011).
525
526
527

528 The age and initial Hf isotopic signature of zircons from the granitic gneiss sample 13DC12 match well with those of ancient detrital zircons from the WDC analyzed by Sarma et al. (2012), Lancaster et al. (2015) and Maibam et al. (2016), which are presented in Figure 9. These authors rationally interpreted this slightly positive initial εHf signature as marking juvenile crust addition. However, if one assumes that ~3410 Ma detrital zircons were derived from lithologies similar to the granitic gneiss studied herein, which is the only rock >3350 Ma identified so far in the WDC, then, the positive εHf signatures become misleading because sample 13DC12 is interpreted as a crust reworking product based on petrographic and geochemical arguments (see section 5.1.1). This example illustrates the fact that Hf isotopic signatures cannot unambiguously discriminate between juvenile addition and crustal reworking when used alone in the detrital zircon record. However, positive εHf in a crustally-derived granitoid indicates that its precursor had a crustal residence time that was short enough so that its Hf isotopic composition was still close to that of its mantle source when it got reworked. In the absence of constraints on the nature of this precursor and its mantle source, we can speculate on lower- and upper-limits for crustal residence time by, respectively, assuming that the minimum time-span between emplacement and
545 reworking of a granitic unit is on the order of ~10 My, and by calculating two-stage
546 model ages (e.g., Blichert-Toft and Albarède, 2008; Hawkesworth et al., 2010). In order
547 to minimize issues inherent to model ages (e.g., Arndt and Goldstein, 1987; Laurent
548 and Zeh, 2015; Payne et al., 2016), we have used end-members from a large range of
549 crustal ¹⁷⁶Lu/¹⁷⁷Hf which characterize average Archean TTGs (0.004; Guitreau et al.,
550 2012) and average continental crust (0.015; Griffin et al., 2004). Assuming a mantle
551 source similar to the arc-mantle (εHf = +13.3; Dhuime et al., 2011; Iizuka et al., 2013),
552 the calculated model ages range from 3466 to 3492 Ma. If, instead, a depleted mantle
553 source (DM) similar to that of MORB (εHf = +17; Chauvel and Blichert-Toft, 2001) is
554 assumed, the model ages become 3503 to 3545 Ma. We cannot conclude on the actual
555 residence time of the precursor to 13DC12 but we note that it can range from ~10 to
556 ~130 My and is, hence, relatively short and included in the range displayed by the oldest
557 detrital zircons (e.g., Nutman et al., 1992; Sarma et al., 2012; Lancaster et al., 2015;
558 Maibam et al., 2016) and igneous zircons (this study) of the WDC.
559

560

6.2.2. Trondhjemitic gneiss (13DC13)

561 Internal textures associated with variable U-Pb ages, Th/U, and initial Hf isotopic
562 compositions in 13DC13 zircons (Figs. 7 and S5) led us to conclude that there is more
563 than one population in this sample, each variably affected by post-crystallization
564 disturbance(s). In order to characterize these populations, we have determined
565 Discordia lines at the scale of each zircon every time analyses done on a same crystal
566 showed consistent initial ¹⁷⁶Hf/¹⁷⁷Hf and that ²⁰⁷Pb/²⁰⁶Pb ages correlated with degrees
567 of U-Pb discordance. Otherwise, ²⁰⁷Pb/²⁰⁶Pb ages and their associated initial ¹⁷⁶Hf/¹⁷⁷Hf
568 were considered separately. Doing so results in the emergence of five groups (Table 4).

560
The first one is represented by three zircon crystals in which the laser-ablation spots were located in zones that we interpreted as xenocrystic cores because they appear as rounded and/or resorbed domains surrounded by oscillatory-zoned outerparts in CL images (Fig. S4). These three zircons exhibit ages of 3468 ± 41 (upper-intercept zircon #4), 3456 ± 20 (upper-intercept zircon #7), and 3414 ± 23 Ma (concordant $^{207}$Pb/$^{206}$Pb zircon #12) that are associated with respective initial Hf isotopic compositions of 0.280742 ± 0.000014, 0.280721 ± 0.000017, and 0.280860 ± 0.000016. These latter are equivalent to $\epsilon_{Hf}$ of +7.5 ± 0.5, +6.4 ± 0.6, and +10.4 ± 0.6 (Table 4), respectively.

The second group is represented by three crystals in which laser-ablation measurements were done in domains resembling xenocrystic cores much like for the first group and that gave ages of 3342 ± 19 (upper-intercept zircon #5), 3356 ± 25 (upper-intercept zircon #11), and 3359 ± 110 (upper-intercept zircon #3). The initial Hf isotopic signatures obtained on the same locations are 0.280720 ± 0.000018, 0.280733 ± 0.000012, and 0.280778 ± 0.000016 (Table 4), respectively, which translates into $\epsilon_{Hf}$ values of +3.7 ± 0.6, +4.5 ± 0.4, and +6.1 ± 0.6.

The third group is represented by only one crystal that gave an age of 3295 ± 18 Ma (grain #6; Fig. S4). This crystal has very reproducible initial Hf isotopic compositions (Table 3) that, when calculated at 3295, give a weighted average of 0.280752 ± 0.000010 which is equivalent to an $\epsilon_{Hf}$ of +3.7 ± 0.4.

The fourth group exhibits ages of 3170 ± 32 and 3179 ± 11 Ma that have been obtained in oscillatory-zoned outer margins of two different crystals. The corresponding initial $^{176}$Hf/$^{177}$Hf are 0.280756 ± 0.000013 and 0.280822 ± 0.000011, which gives $\epsilon_{Hf}$ of +0.8 ± 0.5 and +3.4 ± 0.4, respectively (Table 4).

The fifth group corresponds to an age of 3101 ± 25 Ma that was obtained from two analyses done in one very elongated zircon (Fig. S5). Initial Hf isotopic signature
594 for this zircon is 0.280739 ± 0.000021, which is equivalent to an εHf of -1.4 ± 0.7 (Table 4).
595

596 The calculated lower-intercept ages for the identified Discordia lines, different
597 from ~0 Ma, form two groups with one ranging from 542 ± 160 to 749 ± 90 Ma and
598 another poorly constrained one from 969 ± 770 to 1792 ± 640 Ma, which is due to the
599 limitedly discordant data that define the Discordia lines. The accuracy of the latter
600 group is debatable. However, the first group exhibit ages very compatible with that
601 observed for the granitic gneiss (Fig. 6C) and that comply well with known Pan-African
602 metamorphic events that occurred in southern India (e.g., Bhaskar Rao et al., 1992;
603 Miller et al., 1996).

604 We interpret the trondhjemitic gneiss (13DC13) to have been emplaced at 3178
605 ± 10 Ma, which is the average age of the fourth group, because it corresponds to the
606 age of oscillatory zoned outer margins. Older ages, which are for the most part located
607 in identifiable xenocrystic cores are interpreted as inherited. The age of the fifth group
608 is assumed to be metamorphic because of the internal texture of the crystal and its high
609 Th/U of ~1.2, which is often seen in zircons that formed during high-temperature
610 metamorphism (e.g., Vavra et al., 1999; Möller et al., 2003). This is consistent with the
611 finding of Jayananda et al. (2015) that titanite recovered from neighboring 3200 Ma
612 Halekote-type trondhjemite exhibit ages ranging from 3217 to 3091 Ma, and that these
613 authors interpreted as marking a ca. 3100 Ma metamorphic event in the area around the
614 HSB. We note that the estimated age of crystallization for the trondhjemitic gneiss is
615 close to that of the Chikmagalur granite, which crops out south from the Bababudan
616 belt (Fig. 1; Jayananda et al., 2015), and to that of diapiric trondhjemites observed in
617 the Holenarsipur Schist Belt (Figs. 1 and 2; Jayananda et al., 2015). The inherited zircon
618 ages of 3295, 3342-3359, and 3414 Ma match well with, respectively, a 3298 ± 7 Ma
619 volcanic flow identified within the HSB by Peucat et al., (1995), the 3342 ± 6 Ma
620 Hassan-Gorur gneiss studied by Beckinsale et al., (1980), Bhaskar Rao et al., (2008),
621 and Jayananda et al. (2015), and the 3410.8 ± 3.6 Ma granitic gneiss (13DC12) from
622 this study. Further, the εHf of +4 to +7 determined by Bhaskar Rao et al. (2008) for a
623 3346 ± 10 Ma Gorur gneiss match very well with the values of +3.7 to +6.1 obtained
624 for inherited zircons of the second group, which gave ages of 3342 to 3359 Ma.
625 However, the εHf signature of the granitic gneiss (13DC12), +2.2 ± 0.6, differs
626 significantly from that of the 3414-Ma zircon (i.e., +10.4 ± 0.6) which indicates that
627 although coeval, they did not record the same event. Finally, the trondhjemitic gneiss
628 zircons dated at 3456-3468 Ma do not correspond to any known lithology in the WDC,
629 although such old zircons have been found as detrital crystals (e.g., Nutman et al., 1992;
630 Sarma et al., 2012; Lancaster et al., 2015; Maibam et al., 2016). These oldest detrital
631 zircons exhibit less radiogenic Hf isotope signatures than the inherited ones studied
632 herein.
633

633 The trondhjemitic gneiss (13DC13) is petrographically similar to the Halekote
634 trondhjemites and Chikmagalur granite, which also contain primary muscovite
635 according to descriptions provided in Jayananda et al. (2015). Given all these
636 similarities, as well as the fact that the trondhjemitic gneiss has been sampled in a zone
637 of low strain resembling the central part of a diapir (Fig. 2; Bouhallier et al., 1993), we
638 propose that it is related to the diapiric trondhjemites of the WDC, which are known to
639 contain enclaves of older rocks (e.g., Naqvi and Rogers, 1987; Meen et al., 1992;
640 Jayananda et al., 2015), such as the Bt-rich enclave (13DC15) which itself contains
641 older zircons. Stroh et al. (1983) interpreted these diapiric granitoids as markers of
642 WDC stabilization through removal of heat-producing radioactive elements from the
643 lower crust by reworking. This interpretation is supported by data recently presented in
Jayananda et al. (2015), who also concluded that the dome-and-basin structure of the WDC had been acquired during the emplacement of these trondhjemites ~3200 My ago. This process of stabilization of Archean continental crust has also been suggested for other cratons (e.g., Schoene et al., 2008). When evolutionary paths for felsic and mafic lithologies are taken into account (see Fig. 9), the εHf signatures of the trondhjemitic gneiss 13DC13, represented by the fourth group (+0.8 ± 0.5 and +3.4 ± 0.4 at 3178 Ma; Table 4) can be accounted for by the reworking of various crustal lithologies represented by inherited zircons older than 3200 Ma within 13DC13. Therefore, this Hf isotope variability could be indicative of isotopic heterogeneity within the magma parental to 13DC13 which originated from distinct crustal sources involved during anatexis and/or acquired through interactions with various crustal lithologies. However, we cannot rule out some mixing between unrelated domains because the two analyzed crystals both contained two zones with slightly different Hf isotope signatures (Fig. 6 and S5). According to the ¹⁷⁶Hf/¹⁷⁷Hf of the corresponding domains (Tables 4 and S6), the εHf values mentioned above (i.e., +0.8 and +3.4) could be interpreted as, respectively, minimum and maximum values for the fourth group. Nevertheless, whether or not this heterogeneity is real or analytical is not important for the rest of the discussion. Yet, we note that the Hf isotopic signatures of 13DC13 cognate zircons match very well with those of coeval zircons from all detrital zircon datasets for the WDC (Fig. 9).

The first group (3414-3468 Ma) has εHf signatures more radiogenic than coeval zircons from the detrital record (Fig. 9) implying that either the original host-rocks of zircons from the first group were rare or they were not available for sampling at the surface at the time of sedimentation. These high values (+6 to +10) imply that a strongly depleted mantle source was tapped during the formation of the magma parental to
669 zircons from the first group. Such highly depleted source is rare in the Archean and
670 mostly limited to boninites and komatiites (e.g., Hoffmann et al., 2010; Nebel et al.,
671 2014; Hoffmann and Wilson, 2017).
672

673 **6.2.3. Biotite-rich enclave (13DC15)**

674 The two zircon crystals recovered from this sample show remarkably simple Lu-Hf
675 isotope systematics between the two analyses performed in each zircon (Fig. 8).
676 However, the first zircon (13DC15_1) exhibit a significant variation in age in spite of
677 consistent initial Hf isotopic compositions (Fig 8). This consistency likely indicates that
678 U-Pb systematics have been disturbed at some point in this zircon's evolution. This is
679 also consistent with the fact that oldest zircon $^{207}$Pb/$^{206}$Pb age is associated with a Th/U
680 value that falls within the common magmatic range whereas the youngest age (i.e., 2973
681 Ma; Table 3) is associated with a Th/U <0.2 that can be interpreted as resulting from
682 metamorphism. The oldest age determined for 13DC15_1 is not strictly concordant and,
683 therefore, we have fitted a Discordia line through the two U-Pb analyses, which gave
684 upper- and lower-intercept ages of 3499 ± 29 and 1719 ± 190 Ma, respectively (Fig.
685 S6). Note that the upper-intercept age overlaps within uncertainty with the oldest
686 $^{207}$Pb/$^{206}$Pb age determined for this zircon (13DC15_1). U-Pb ages are very consistent
687 in the second crystal which gives a combined crystallization age of 3607 ± 16 Ma (Fig.
688 S6)

689 Average initial $^{176}$Hf/$^{177}$Hf for the two zircons analyzed (i.e., 13DC15_1 and
690 13DC15_2) are 0.280476 ± 0.000011 and 0.280374 ± 0.000014, respectively, which
691 correspond to εHf values of -1.3 ± 0.4 and -2.3 ± 0.5 at 3499 and 3607 Ma, respectively
692 (Table 4).
The zircons from the biotite-rich enclave exhibit not only ages >3400 Ma but, contrary to zircons from other samples studied herein, negative initial εHf that, hence, suggest that the magmas parental to these zircons originated from, or were buffered by, crustal lithologies with long crustal residence times. Using an arc-mantle source (see section 5.1.1) and assuming that the precursor can be either felsic (¹⁷⁶Lu/¹⁷⁷Hf = 0.004) or mafic (¹⁷⁶Lu/¹⁷⁷Hf = 0.022), calculated two-stage model ages (e.g., Blichert-Toft and Albarède, 2008; Hawkesworth et al., 2010) are 3684 and 3891 Ma for zircon #1, and 3821 and 4060 Ma for zircon #2. If instead we use a depleted mantle source (see section 5.1.1), the model ages become 3713 and 3937 Ma for zircon #1, and 3846 and 4094 Ma for zircon #2. Finally, using BSE composition from Iizuka et al. (2015) for the mantle source of the precursors we obtain ages of 3558 and 3649 Ma for zircon #1, and 3715 and 3880 Ma for zircon #2. These model ages are too variable and rely on too unconstrained assumptions to be interpreted as are but nevertheless illustrate the fact that very old crust, up to 4000 Ma, could have been involved in the formation of the magma parental to 13DC15 zircons.

## 6.3. Early formation of the Western Dharwar Craton

Our new results, though limited, bring important constraints that can be used in combination with previous studies to discuss the early formation of the WDC in terms of sources involved. We can further compare these latter to the latest models for WDC formation (e.g., Jayananda et al., 2008, 2015; Lancaster et al., 2015) to speculate on the geological setting of WDC early formation. Figure 9 presents our results in the context of detrital zircon datasets available for the WDC and that have been used to depict the big-picture evolution of the WDC (i.e., Sarma et al., 2012; Lancaster et al., 2015; Maibam et al., 2016). Figure 9 also includes the age range for Sargur-group komatiites
(Jayananda et al., 2008) and U-Pb ages alongside ε<sub>Hf</sub> for Gorur gneiss from Bhaskar Rao et al., (2008). It can be seen that all zircons analyzed in this study have detrital equivalents, except for the most radiogenic zircons from 13DC13's first group (3414-3468 Ma; Fig. 9). Although essentially consistent, slight differences can be observed between the ages and ε<sub>Hf</sub> displayed in the detrital records of Figure 9, which likely arise from distinct catchment basins and possibly the number of analyses. The early formation of the WDC can be divided into three time-periods: (1) pre-3400 Ma, (2) 3400-3200 Ma, (3) post-3200 Ma.

Zircons older than 3400 Ma exhibit large variations in ε<sub>Hf</sub> signatures (Fig. 9) testifying to various sources which likely points to different contexts of formation for their parental granitoids. These sources are mantle domains with ancient depletion history, mantle domains with moderately depleted signatures that are equivalent to those observed in WDC granitoids formed during the second period, and enriched crusts of possibly old ages (up to 4000 Ma). Most zircons that testify to this period are inherited crystals in the 3178 Ma trondhjemitic gneiss (13DC13) and detrital zircons from the Sargur-group, which have deposition ages estimated between 3100 and 3300 Ma. The role of the source to these zircons parental granitoids is discussed later on.

In the time-span 3400-3200 Ma, all detrital zircon records show positive ε<sub>Hf</sub> varying within the same restricted range, except for zircons from the Sargur Schist Belt (Lancaster et al., 2015) which, nevertheless, also show a restricted range but around chondritic values. This indicates that during this time-period, granitoids were sourced in a common mantle domain that had mildly-depleted to near-chondritic Hf isotopic compositions, with limited or no continental influence, similar to global data for TTGs presented by Guitreau et al. (2012). In Figures 9B and 9D, an enhanced variability of ε<sub>Hf</sub> is visible around 3250-3200 Ma and is associated with a shift towards negative
values that can be seen in **Figures 9C** and **9D**. Moreover, the ~3220 Ma granitic clast analyzed in Maibam et al. (2016) contains pre-3400 Ma zircons that have ε<sub>Hf</sub> similar to that of the granitic sample (13DC12) from this study (Fig. 9D). These features can be accounted for by reworking of WDC's oldest lithologies, buffering of newly formed magmas by older lithologies, and/or a continental influence similar to what can be seen in Svecofennian provinces of northern Sweden (e.g., Öhlander et al., 1993), the Kohistan-Ladakh arc (e.g., Bouilhol et al., 2013), and the Sunda-Banda arc (e.g., Elburg et al., 2005; Herrington et al., 2011), for example.

After ~3200 Ma, all datasets, but that for Bababudan-group sediments for which there is no data younger than 3200 Ma (Lancaster et al., 2015), exhibit a drift of ε<sub>Hf</sub> towards increasingly negative values as age decreases. The deposition age of the sediments from which detrital zircons were recovered are not well constrained, except for the Gadag Greenstone Belt (Sarma et al., 2012). Sargur-group sediments are assumed to have been deposited between ~3300 and ~3100 Ma depending on their location within the WDC and the way the sedimentation age was estimated (e.g., Nutman et al., 1992; Ramakrishnan et al., 1994; Peucat et al., 1995; Sarma et al., 2012; Hokada et al., 2013). When minimum deposition ages are taken into account (Fig. 9), the major part of the drifts in ε<sub>Hf</sub> through time appear artificial for datasets related to Sargur-group sediments because most ages are younger than that of deposition and are most likely related to ancient U-Pb disturbance and/or recrystallization as noted by Lancaster et al. (2015). It is interesting to note that datasets from Lancaster et al. (2015) and Maibam et al. (2016) contain zircons with ages and ε<sub>Hf</sub> that comply well with the fifth group of the trondhjemitic gneiss (13DC13) and that we interpreted as metamorphic (Figs. 9C and 9D). This example illustrates the fact that detrital zircons are very powerful at unveiling big-picture information about the continental crust
formation and evolution but they can also provide ambiguous information because evolution patterns of crustal segments (e.g., Zeh et al., 2011; Laurent and Zeh, 2015) and artificial trends resulting from ancient Pb-loss look the same in ε<sub>Hf</sub> versus age diagrams, as already pointed out elsewhere (e.g., Amelin et al., 2000; Guitreau and Blichert-Toft, 2014; Payne et al., 2016). As a consequence, we have not considered detrital zircon data for ages younger than 3100 Ma. Yet, the drift observed in Sarma et al. (2012) dataset is real and is also visible with data from the Eastern Dharwar craton (e.g., Maibam et al., 2016). This indicates that after ~3200 Ma, the WDC magmatic events dominantly involved crust reworking processes and/or buffering of magmas by dominant lithologies, not unlike what was proposed by Laurent and Zeh (2015) for the Pietersburg block. This is consistent with conclusions of Bhushan and Sahoo (2010) and Maibam et al. (2011) that stable continental crust was formed in the WDC prior to 3 Ga. Further, Taylor et al. (1984) and Jayananda et al. (2015) concluded from major and trace elements, as well as Sr, Pb, and Nd isotopes that granitoids younger than 3200 Ma contained a pre-existing crust component.

Sargur-group komatiites have long been considered as the oldest units of the WDC (e.g., Naqvi, 1983) until the discovery of detrital zircons as old as 3600 Ma by Nutman et al. (1992). The best age estimate for these komatiites is 3352 ± 110 Ma (Jayananda et al., 2008), which is, hence, not precise enough to conclude on the actual role of these ultramafic rocks in the early development of the WDC. Nevertheless, Naqvi et al. (1983) and Jayananda et al. (2008) noted that some of the oldest identifiable generations of peninsular gneisses intruded into the surrounding greenstones of the HSB, hence, indicating that most of the peninsular gneisses are younger than Sargur-group komatiites. Jayananda et al. (2008, 2016) concluded from elemental and isotopic geochemistry that Sargur-group komatiites formed remote from continental crust.
Therefore, these authors proposed that komatiites of the Sargur group formed in an oceanic-plateau-like environment and were accreted to a continental nucleus that contained lithologies represented by the >3400 Ma detrital zircons (e.g., Kunugiza et al., 1996; Jayananda et al., 2008). This scenario is not unlike what was proposed for other Precambrian terranes (e.g., Boher et al., 1992; Puchtel et al., 1999; Rey et al., 2003; Guitreau et al., 2012; Martin et al., 2014), and it is consistent with our observations for the WDC. Recently, Baes et al. (2016) illustrated using numerical modeling that the fact that the emplacement of a mantle plume in the lithosphere could initiate subduction. We propose a similar scenario whereby the emplacement of an oceanic plateau, comprising the Sargur-group komatiites, initiated subduction beneath it that resulted in the generation of the oldest peninsular gneisses. We further propose that this subduction acted as a “conveyor belt” that induced the accretion to this oceanic plateau of oceanic arcs, smaller oceanic plateaus and crustal segments much like it has been proposed for North America (e.g., Hoffman, 1988; Whitmeyer and Karlstrom, 2007), the Svecofennian Orogen (e.g., Weihed et al., 2005; Guitreau et al., 2014) and the Kohistan-Ladakh arc (e.g., Bouilhol et al., 2013). The accretion to the oceanic plateau of several oceanic arcs and smaller oceanic plateaus would account for the various unrelated chemical and isotopic signatures of peninsular gneisses found throughout the WDC (e.g., Bhaskar Rao et al., 1983; Monrad, 1983; Naqvi et al., 2009; Jayananda et al., 2015). Further, this scenario can account for the low- and high-pressure sources for peninsular gneisses identified by Jayananda et al. (2015) because the size and buoyancy of these mafic-ultramafic segments can control the modality of subduction (i.e., fast or low; shallow or steep). Accretion of oceanic arcs and oceanic plateaus could also account for the short-crustal residence time of sources to peninsular gneisses, as interpreted by Bhaskar Rao et al. (1991), Jayananda et al. (2015), and as
concluded for sample 13DC12 (this study). We surmise that accretion of oceanic arcs could induce crustal reworking which would be consistent with the fact that some of the oldest granitoids of the WDC have peraluminous characteristics despite Nd and Hf isotope signatures similar to mildly depleted mantle sources (Jayananda et al., 2015; this study). If we interpret the granitic gneiss 13DC12 as the reworking product of oceanic arc granitoids during accretion to an oceanic plateau represented by Sargur-group komatiites, then, the sample 13DC12 gives a minimum age of 3410 Ma for this oceanic plateau and the initiation of the WDC growth. The role of ancient crust represented by 3500-3600 Ma zircons is hard to understand and needs further investigation. However, it appears from Figure 9 that such ancient crust did not influence the εHf signatures of granitoids in the catchment basins of sediments from Bababudan, Chitradurga, and Gadag Schist belt before ~3200 Ma. In contrast, sediments in the Sargur Schist Belt had a distinct catchment basin as testified to by the εHf of detrital zircons in Figure 9C. The granitoids parental to these latter zircons appear to have been possibly influenced by 3500-3600 Ma crust, as represented by zircons from 13DC15, earlier than 3200 Ma. Further, the granitoids parental to these latter could have been part of the catchment basin of Sargur Schist Belt sediments. However, the large uncertainty on detrital zircon ages in Figure 9C, prevents accurate conclusions to be drawn. Nevertheless, we see the absence of influence of the ancient crust, represented by zircons from 13DC15, in the εHf signatures of most of detrital zircons from the WDC (Fig. 9) as an argument in favor of the absence of this ancient crust in the vicinity of the HSB prior to ~3200 Ma. We suggest that a large crustal block containing 3500-3600 Ma zircons was accreted to the WDC around 3200 Ma, which initiated the stabilization of, at least, portions of the WDC (e.g., HSB) and the buffering of newly formed magmas by dominant enriched lithologies represented by 3400-3200
Ma peninsular gneisses and 3600-3400 Ma granitoids (Fig. 9). This event marked a change in the growth style of the WDC that is substantiated by the drift of detrital zircons εHf values (Fig. 9) which could correspond, at least in part, to hidden crustal growth (see Laurent and Zeh, 2015; Payne et al., 2016; Couzinié et al., 2016). Remnants of this crustal block, which is intrinsic to the WDC record, may be in the vicinity of the HSB but more likely around the Sargur Schist Belt.

In order to reconstruct the detailed tectono-magmatic history of the WDC and test models for its geological setting, future work will have to focus on documenting ages and signatures of peninsular gneisses in greater details, as well as understanding their stratigraphic relationships and spatial distribution. One important aspect to target is the role of the ancient crust identified herein. Doing so will help refine the above-explained scenario and its local variations that can account for differences in Hf isotopic signatures exhibited by the various detrital zircon records shown in Figure 9. Finally, the same work will have to be conducted in supracrustal belts in order to clarify their origin and relationships with peninsular gneisses.

## 7. Conclusions

We have studied the petrography of a Western Dharwar Craton granitic gneiss and trondhjemitic gneiss, as well as a Bt-rich enclave within the latter, and measured their zircon U-Pb ages and Lu-Hf isotope systematics to shed new light on crustal formation processes during the early formation of the WDC. Our study reveals that crust older than the oldest known granitoid of the WDC (3342-Ma Hassan-Gorur gneiss; Beckinsale et al., 1980; Jayananda et al., 2015), which was known from the detrital zircon record (e.g., Nutman et al., 1992), is also present in the igneous record in the form of a 3410.8 ± 3.6 Ma granitic gneiss and inherited zircons, with ages up to 3607
868 ± 16 Ma, in a 3178 Ma trondhjemitic gneiss and a mica-rich enclave found within this
869 trondhjemite. Hf isotopic signatures indicate short-crustal residence time for the
870 precursor to the granitoids parental to analyzed zircons, except for the oldest ones that
871 could have been sourced from Eoarchean-Hadean precursor(s).

872 Our results compared with similar data for detrital zircons from four locations
873 throughout the WDC allow three time periods to be distinguished. The first one is pre-
874 3400 Ma and exhibit multiple zircon εHf signatures (very depleted to slightly enriched;
875 εHf of +10.4 to -2.3) testifying to the involvement of several distinct sources in the
876 formation of pre-3400 Ma units. The second period is from 3400 to 3200 Ma and
877 corresponding zircons display either mildly-depleted or near-chondritic Hf isotopic
878 signatures, depending on the sampling location of sediments, that vary within a
879 restricted range throughout this period. This indicates involvement of a common
880 juvenile source with limited or no continental influence until ~3200 Ma, when the third
881 period started. This latter is characterized by dominant crust reworking or buffering of
882 newly formed granitoids by pre-existing ones, which translates into a drift of εHf
883 signatures towards increasingly negative values. We propose a scenario updated from
884 that of Jayananda et al. (2008) for the early formation of the WDC in which the arrival
885 of a mantle plume in the upper-mantle gave rise to an oceanic plateau that contained
886 Sargur-group komatiites. The formation of this oceanic plateau triggered subduction on
887 its egdes in a way similar to that described in models from Baes et al. (2016). The
888 subducted oceanic-like crust acted as a conveyor belt that dragged crustal blocks in the
889 vicinity of the oceanic plateau which included short-lived oceanic arcs and small
890 oceanic plateaus which ultimately contributed to the growth of the WDC. We suggest
891 that this subduction started at least 3410 My ago and lasted until at least 3200 Ma when
892 a continental block containing the granitoids parental to the >3410 Ma zircons got
893 accreted to the WDC, hence, inducing its stabilization. The WDC further grew and
894 evolved but newly formed granitoids were buffered by, or sourced in, dominant
895 lithologies of the WDC.

896

897 Acknowledgements:

898 We thank Steve Mozjsis and the CRIO group for help with zircon separation, Nancy
899 Cherim and Mark Townley for help with CL image acquisition, Julia G. Bryce and
900 Maria F. Fahnestock for technical help at UNH. Jean-Louis Paquette and Abdel-
901 Mouhcine Gannoun are thanked for assistance with analyses at the Laboratoire Magmas
902 et Volcans. We are grateful to Claire Fonquernie and Mhammed Benbakkar for rock
903 crushing and major-oxide analyses at Laboratoire Magmas et Volcans. Discussions
904 with Hervé Martin helped improve the present manuscript. Martin Guitreau
905 acknowledges financial support from Matthias Willbold through NERC grant R117299
906 and the Région Auvergne through the Auvergne Fellowship program. This is a
907 Laboratory of Excellence ClerVolc contribution. The University of New Hampshire
908 supported this research project through start-up funds granted to Dr. Samuel B. Mukasa.
909 Last but not least, we would like to thank Randall Parrish for efficient editorial handling
910 as well as Tsuyoshi Iizuka, Sukanta Dey, and an anonymous reviewer for insightful
911 comments that helped improve this manuscript.

912

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1311

1312 **Figure captions**

1313 Table 1. Summary of the Archean geology of the Western Dharwar craton after Naqvi

1314 and Rogers (1987), Yoshida et al. (1994), Naqvi et al. (2009), and Dey (2013).

1315

1316 Table 2. Details of rock sampling location and petrography.

1317

1318 Table 3. Summary of U-Pb and Lu-Hf isotope results for Indian zircons analyzed by

1319 LA-ICP-MS and LA-MC-ICP-MS

1320

1321 Table 4. Interpreted U-Pb ages and Lu-Hf isotope systematics for Indian zircons

1322 analyzed herein

1323

1324 Figure 1. Detailed geological map of the Dharwar craton adapted from Chardon et al.

1325 (2008) and Dey (2013). WDC and EDC refer to Western and Eastern Dharwar Cratons,

1326 respectively. Major schist belts have been reported and names are indicated as follows;

1327 B for Banasandra, Bb for Bababudan, Ch for Chitradurga, G for Ghattihosahalli, Ga for

1328 Gadag, Ho for Holenarsipur, J for Jayachamarajapura (J.C. Pura), K for Kalyadi, Ku
1329 for Kudremuh, N for Nuggihalli, S for Sandur, Sh for Shimoga, and Sg for Sargur. The
1330 inset shows where Figure 1 locates respective to India.

1331

1332 Figure 2. Merged geological and structural map of the Holenarsipur Schist Belt
1333 (Western Dharwar Craton, Southern India), from Bouhallier et al. (1993), with location
1334 of samples collected for this study (red dots).

1335

1336 Figure 3. Photos of sampling locations with corresponding thin section images in
1337 polarized and cross-polarized light for samples 13DC12 (Figs. 3A-3C) and 13DC13
1338 (Figs. 3D-3F). Note the hammer and the chisel, with orange handle, for scale in 3A and
1339 3D, respectively. Mineral names are reported as Qz for quartz, Plg for plagioclase, Kf
1340 for K-Feldspar (essentially microcline), Bt for biotite, and Ms for muscovite.

1341

1342 Figure 4. Diagrams presenting the major characteristics of samples 13DC12 and
1343 13DC13 based on major and minor element concentrations. Figure A is an An-Ab-Or
1344 normative plot that discriminates granitoid types (after O'Connor, 1965 and Barker,
1345 1979). Figure B is a diagram that indicates granite chemical affinity according to the
1346 classification proposed by Shand (1943). Figure C is MALI index after Frost et al.
1347 (2001) with field compositions after Martin and Moyen (2012) and Laurent et al.
1348 (2014). Figure D is a classification of late-Archean granitoids proposed in Laurent et
1349 al. (2014). Figure E is a ternary diagram that presents the compositional field of melts
1350 produced by a range of possible sources (i.e., low-K and high-K mafic rocks, as well as
1351 tonalities and metasediments). This diagram can be used to infer granite sources using
1352 major element concentrations (after Laurent et al., 2014).

1353
1354 Figure 5. Coupled U-Pb and Lu-Hf isotope results for zircons from sample 13DC12.

1355 Dashed lines represent closed-system evolution of the Lu-Hf isotope system using the
1356 <sup>176</sup>Lu/<sup>177</sup>Hf indicated next to each line, which correspond to the lowest and highest
1357 values measured for this zircon population, and assuming that the initial <sup>176</sup>Hf/<sup>177</sup>Hf is
1358 the average of those visible in the inset. Note the general good match between
1359 datapoints and evolution lines.

1360

1361 Figure 6. Summary of 13DC12 zircon U-Pb geochronology. Figure A is a Concordia
1362 plot displaying the most concordant and oldest least discordant U-Pb data from
1363 13DC12. Figure B presents the weighted average <sup>207</sup>Pb/<sup>206</sup>Pb age for U-Pb data shown
1364 in Figure A. Figure C is a Concordia diagram that shows U-Pb data for all other zircons
1365 from 13DC12.

1366

1367 Figure 7. Coupled U-Pb and Lu-Hf isotope results for zircons from sample 13DC13.
1368 As in Figure 4, dashed lines represent closed-system evolution of the Lu-Hf isotope
1369 system using the <sup>176</sup>Lu/<sup>177</sup>Hf indicated next to each line, which correspond to the lowest
1370 and highest values measured, and assuming that the initial <sup>176</sup>Hf/<sup>177</sup>Hf is the average of
1371 the oldest zircons.

1372

1373 Figure 8. Coupled U-Pb and Lu-Hf isotope results for zircons from sample 13DC15.
1374 The dashed line represents closed-system evolution of the Lu-Hf isotope system using
1375 the <sup>176</sup>Lu/<sup>177</sup>Hf measured in 13DC15_1b and the initial <sup>176</sup>Hf/<sup>177</sup>Hf from 13DC15_1a.

1376

1377 Figure 9. Compilation of available U-Pb and Lu-Hf isotope data for detrital zircons
1378 from the Western Dharwar Craton (Sarma et al., 2012; Lancaster et al., 2015; Maibam
<table>
  <tr>
    <td>1379</td>
    <td>et al., 2016), combined with data from this study, and those for Gorur gneiss from Bhaskar Rao et al. (2008). Also shown is the age range for Sargur-group komatiites analyzed by Jayananda et al. (2008) using the Sm-Nd isotope system. Bulk Silicate Earth (BSE) parameters are those from Iizuka et al. (2015) and arc-mantle evolution is deduced from a present-day εHf of +13.3 (Dhuime et al., 2011; Iizuka et al., 2013).</td>
  </tr>
  <tr>
    <td>1380</td>
    <td>Dashed lines indicate the evolution paths for reservoirs with mafic (<sup>176</sup>Lu/<sup>177</sup>Hf = 0.02) and felsic (TTG; <sup>176</sup>Lu/<sup>177</sup>Hf = 0.005) compositions. See text for details.</td>
  </tr>
  <tr>
    <td>1381</td>
    <td></td>
  </tr>
  <tr>
    <td>1382</td>
    <td></td>
  </tr>
  <tr>
    <td>1383</td>
    <td></td>
  </tr>
  <tr>
    <td>1384</td>
    <td></td>
  </tr>
  <tr>
    <td>1385</td>
    <td></td>
  </tr>
  <tr>
    <td>1386</td>
    <td></td>
  </tr>
  <tr>
    <td>1387</td>
    <td>Captions to supplementary Figures and Tables:</td>
  </tr>
  <tr>
    <td>1388</td>
    <td>Table S1. Major and minor oxide abundances for the orthogneisses analyzed in this study</td>
  </tr>
  <tr>
    <td>1389</td>
    <td></td>
  </tr>
  <tr>
    <td>1390</td>
    <td></td>
  </tr>
  <tr>
    <td>1391</td>
    <td>Table S2. LA-ICP-MS and LA-MC-ICP-MS operating conditions</td>
  </tr>
  <tr>
    <td>1392</td>
    <td></td>
  </tr>
  <tr>
    <td>1393</td>
    <td>Table S3. U-Pb isotope results for the zircon standard 91500 analyzed by LA-ICP-MS.</td>
  </tr>
  <tr>
    <td>1394</td>
    <td></td>
  </tr>
  <tr>
    <td>1395</td>
    <td>Table S4. U-Pb isotope results for Indian zircons analyzed by LA-ICP-MS.</td>
  </tr>
  <tr>
    <td>1396</td>
    <td></td>
  </tr>
  <tr>
    <td>1397</td>
    <td>Table S5: Lu-Hf isotope results for zircon standards analyzed by LA-MC-ICP-MS</td>
  </tr>
  <tr>
    <td>1398</td>
    <td></td>
  </tr>
  <tr>
    <td>1399</td>
    <td>Table S6. Lu-Hf isotope results for Indian zircons analyzed by LA-MC-ICP-MS</td>
  </tr>
  <tr>
    <td>1400</td>
    <td></td>
  </tr>
  <tr>
    <td>1401</td>
    <td>Figure S1. Concordia plot and weighted average <sup>207</sup>Pb/<sup>206</sup>Pb for the zircon standard 91500 that was used as a quality check in this study.</td>
  </tr>
  <tr>
    <td>1402</td>
    <td></td>
  </tr>
  <tr>
    <td>1403</td>
    <td></td>
  </tr>
</table>
1404 Figure S2. Plots showing the accuracy of Hf isotope measurements performed on
1405 standards in this study. ε<sub>Hf</sub> values presented in this figure correspond to those visible in
1406 Table S5 which were calculated by normalization to the accepted values of the
1407 corresponding zircon standard also provided in Table S5.

1408

1409 Figure S3. Concordia plot for zircons from the granitic gneiss (13DC12) with
1410 corresponding cathodo-luminescence images.

1411

1412 Figure S4. Concordia plot for zircons from the trondhjemitic gneiss (13DC13) with
1413 corresponding cathodo-luminescence images.

1414

1415 Figure S5. Concordia plot of all U-Pb data for 13DC13 zircons (A) and 207Pb/206Pb age
1416 vs. Th/U plot for corresponding zircons (B). White-filled symbols correspond to low-
1417 Th/U zircons whereas those filled with grey and black correspond to zircons with Th/U
1418 that comply with the common magmatic range and high-Th/U zircons, respectively.

1419

1420 Figure S6. Concordia plot for zircons from 13DC15 with corresponding transmitted
1421 light and cathodo-luminescence images.

1422
<figure><img src="image_2.png" /><figcaption>Figure 1</figcaption></figure>
<figure><img src="image_3.png" /><figcaption>Figure 2</figcaption></figure>
<figure><img src="image_4.png" /><figcaption>Figure 3</figcaption></figure>
<figure><img src="image_5.png" /></figure>

<figure><img src="image_6.png" /></figure>

<figure><img src="image_7.png" /></figure>

<figure><img src="image_8.png" /></figure>

<figure><img src="image_9.png" /></figure>

<figure><img src="image_10.png" /></figure>
<figure><img src="image_11.png" /></figure>
<figure><img src="image_12.png" /><figcaption>Figure 6</figcaption></figure>
<figure><img src="image_13.png" /><figcaption>Figure 7</figcaption></figure>
<figure><img src="image_14.png" /><figcaption>Figure 8</figcaption></figure>
<figure><img src="image_15.png" /><figcaption>Figure 9</figcaption></figure>

<figure><img src="image_16.png" /></figure>

<figure><img src="image_17.png" /></figure>

<figure><img src="image_18.png" /></figure>
<table><caption>Table 1. Summary of the Archean geology of the Western Dharwar craton after Naqvi and Rogers (1987), Yoshida et al. (1994), Naqvi et al. (2009), and Dey (2013)</caption><thead><tr><th>Supracrustal rocks</th><th>Granitic rocks</th><th>Lithologies</th><th>Additional information</th></tr></thead><tbody><tr><td><strong>Dharwar Supergroup</strong><br>(~2500 to ~2900 Ma)<br><br><strong>Chitradurga group</strong><br>-------Unconformity-------<br><br><strong>Bababudan group (3.2-3.0 Ga?)</strong><br>-------Unconformity-------</td><td><strong>Closepet granite</strong><br>(~2500 to ~2600 Ma)</td><td>K-rich granite<br><br>Conglomerate, quartzite, greywacke, pelite, BIF, basalt<br><br>Conglomerate, quartzite, basalt, BIF</td><td>Oldest reported detrital zircon in Gadag greenstone belt: 3542 ± 9 Ma (Sarma et al., 2012)<br><br>Oldest reported detrital zircon: 3634 ± 10 Ma (Bhaskar Rao et al., 2008)</td></tr><tr><td><strong>Sargur group</strong><br>(~3000 to ~3400 Ma)</td><td><strong>Diapiric bodies</strong><br>(~3100 to ~3200 Ma)</td><td>Trondhjemite (Halekote) and granite/granodiorite (Chikmagalur)<br><br>Quartzite, pelite, calc-silicate, basalt, komatiite, BIF, layered mafic-ultramafics<br><br>Tonalite-trondhjemite-granodiorite and granite</td><td>Contains remnants of older greenstones and basement gneisses (e.g., Meen et al., 1992; Jayananda et al., 2015; this study). Inherited igneous zircon: 3607 ± 16 Ma (this study)<br><br>Oldest age of 3352 ± 110 Ma from komatiites (Jayananda et al., 2008). Detrital zircons indicate a range from 3580 to 3130 Ma (Nutman et al., 1992). Lancaster et al. (2015) reported an oldest detrital zircon age of 3555 ± 95 Ma.<br><br>Oldest generations: 3342 ± 6 Ma (Gorur gneiss; Beckinsale et al., 1980; Jayananda et al., 2015), 3350 ± 9 Ma (Chikmagalur gneiss; Jayananda et al., 2015), and 3410.8 ± 3.6 Ma (this study)</td></tr><tr><td></td><td><strong>Peninsular gneisses</strong><br>(~3200 to ~3400 Ma)</td><td></td><td></td></tr><tr><td></td><td><strong>Older basement</strong><br>(up to ~3600 Ma)</td><td>TTG?</td><td>Existence inferred from detrital and inherited zircons (e.g., Nutman et al., 1992; Bhaskar Rao et al., 2008; Lancaster et al., 2015; this study)</td></tr></tbody></table>
<table><caption>Table 2. Sample locations and petrographic details of the samples analyzed in this study</caption><thead><tr><td>Sample name</td><td>Locality</td><td>GPS Coordinates</td><td>Rock type</td></tr></thead><tbody><tr><td>13DC12</td><td>Near Byadarahalli (Karnataka)</td><td>N12°52.463' E076°05.686'</td><td>Granitic gneiss</td></tr><tr><td>13DC13</td><td>Near Javenahalli (Karnataka)</td><td>N12°55.461' E076°04.809'</td><td>Trondhjemitic gneiss</td></tr><tr><td>13DC15</td><td>Near Javenahalli (Karnataka)</td><td>N12°55.461' E076°04.809'</td><td>Bt-rich enclave within 13DC13</td></tr></tbody></table>

<footnote>* Qz is for quartz, Plg for plagioclase, K-Feld for alkali feldspar, Bt for biotite, Msc for muscovite, Op for opaque pha</footnote>
Mineralogy

Qz, Plg, K-Feld, Bt, Msc, ± Op

Qz, Plg, K-Feld, Bt, Msc, ± Op

Bt, Qz, Plg, ± K-Feld, ± Msc, ± Chl

yses, and Chl for chlorite
<table><caption>Table 3. Summary of U-Pb and Lu-Hf isotope results for Indian zircons analyzed by LA-ICP-MS</caption><thead><tr><th>Sample</th><th>U</th><th>Th<br>(ppm)</th><th>Pb</th><th>Th/U<sub>c</sub></th><th>Age (Ma)<br>(Ma)</th><th>2σ</th><th>Disc.</th><th><sup>176</sup>Hf/<sup>177</sup>Hf</th><th>2σ<br>(x10<sup>-6</sup>)</th><th><sup>176</sup>Lu/<sup>177</sup>Hf</th></tr></thead><tbody><tr><td colspan="11"><strong>Granitic gneiss</strong></td></tr><tr><td>13DC12_1a</td><td>1334</td><td>257</td><td>561</td><td>0.41</td><td>3137</td><td>10</td><td>54%</td><td>0.281023</td><td>18</td><td>0.00460</td></tr><tr><td>13DC12_1b</td><td>1691</td><td>394</td><td>751</td><td>0.44</td><td>3100</td><td>15</td><td>51%</td><td>0.280990</td><td>22</td><td>0.00489</td></tr><tr><td>13DC12_2a</td><td>2837</td><td>1205</td><td>763</td><td>0.49</td><td>2696</td><td>11</td><td>71%</td><td>0.281124</td><td>29</td><td>0.00689</td></tr><tr><td>13DC12_2b</td><td>2072</td><td>1762</td><td>720</td><td>0.61</td><td>2815</td><td>9</td><td>61%</td><td>0.280890</td><td>23</td><td>0.00365</td></tr><tr><td>13DC12_3_1</td><td>538</td><td>201</td><td>442</td><td>0.51</td><td>3411</td><td>11</td><td>26%</td><td>0.280772</td><td>21</td><td>0.00209</td></tr><tr><td>13DC12_3_2</td><td>260</td><td>119</td><td>292</td><td>0.61</td><td>3416</td><td>12</td><td>7%</td><td>0.280772</td><td>21</td><td>0.00209</td></tr><tr><td>13DC12_4</td><td>253</td><td>48</td><td>230</td><td>0.39</td><td>3403</td><td>7</td><td>18%</td><td>0.280723</td><td>15</td><td>0.00167</td></tr><tr><td>13DC12_5a</td><td>262</td><td>80</td><td>270</td><td>0.30</td><td>3413</td><td>7</td><td>0%</td><td>0.280757</td><td>16</td><td>0.00186</td></tr><tr><td>13DC12_5b</td><td>302</td><td>99</td><td>311</td><td>0.30</td><td>3410</td><td>4</td><td>1%</td><td>0.280734</td><td>14</td><td>0.00165</td></tr><tr><td>13DC12_6</td><td>1277</td><td>1155</td><td>994</td><td>0.63</td><td>3403</td><td>10</td><td>37%</td><td>0.280875</td><td>24</td><td>0.00361</td></tr><tr><td>13DC12_7</td><td>471</td><td>631</td><td>504</td><td>0.99</td><td>3408</td><td>6</td><td>26%</td><td>0.280766</td><td>12</td><td>0.00198</td></tr><tr><td>13DC12_8a</td><td>2849</td><td>1454</td><td>1027</td><td>0.71</td><td>2939</td><td>12</td><td>62%</td><td>0.280855</td><td>25</td><td>0.00394</td></tr><tr><td>13DC12_8b</td><td>1352</td><td>463</td><td>640</td><td>0.46</td><td>3143</td><td>20</td><td>50%</td><td>0.281032</td><td>24</td><td>0.00633</td></tr><tr><td>13DC12_9a</td><td>615</td><td>660</td><td>498</td><td>0.63</td><td>3324</td><td>7</td><td>33%</td><td>0.280767</td><td>19</td><td>0.00219</td></tr><tr><td>13DC12_9b</td><td>456</td><td>284</td><td>462</td><td>0.48</td><td>3365</td><td>6</td><td>11%</td><td>0.280685</td><td>32</td><td>0.00167</td></tr><tr><td>13DC12_10a</td><td>581</td><td>483</td><td>519</td><td>0.74</td><td>3425</td><td>18</td><td>25%</td><td>0.280884</td><td>43</td><td>0.00313</td></tr><tr><td>13DC12_10b</td><td>1523</td><td>1530</td><td>550</td><td>0.56</td><td>3024</td><td>33</td><td>63%</td><td>0.280816</td><td>20</td><td>0.00317</td></tr><tr><td>13DC12_11a</td><td>1088</td><td>827</td><td>856</td><td>0.63</td><td>3388</td><td>15</td><td>33%</td><td>0.280869</td><td>36</td><td>0.00426</td></tr><tr><td>13DC12_11b</td><td>1060</td><td>802</td><td>805</td><td>0.66</td><td>3366</td><td>21</td><td>39%</td><td>0.280766</td><td>30</td><td>0.00272</td></tr><tr><td>13DC12_12a</td><td>1328</td><td>1141</td><td>554</td><td>0.83</td><td>2947</td><td>16</td><td>58%</td><td>0.280886</td><td>25</td><td>0.00369</td></tr><tr><td>13DC12_12b</td><td>1958</td><td>3334</td><td>742</td><td>0.13</td><td>3310</td><td>15</td><td>28%</td><td>0.280833</td><td>15</td><td>0.00271</td></tr><tr><td>13DC12_13a</td><td>640</td><td>201</td><td>374</td><td>0.37</td><td>3235</td><td>14</td><td>43%</td><td>0.280733</td><td>15</td><td>0.00177</td></tr><tr><td>13DC12_13b</td><td>271</td><td>86</td><td>218</td><td>0.52</td><td>3365</td><td>15</td><td>24%</td><td>0.280739</td><td>13</td><td>0.00214</td></tr><tr><td colspan="11"><strong>Trondhjemitic gneiss</strong></td></tr><tr><td>13DC13_3a</td><td>348</td><td>292</td><td>363</td><td>1.02</td><td>3278</td><td>19</td><td>6%</td><td>0.280841</td><td>20</td><td>0.00114</td></tr><tr><td>13DC13_3b</td><td>341</td><td>314</td><td>318</td><td>1.02</td><td>3187</td><td>14</td><td>10%</td><td>0.280885</td><td>24</td><td>0.00143</td></tr><tr><td>13DC13_4_1</td><td>512</td><td>27</td><td>455</td><td>0.22</td><td>3424</td><td>17</td><td>10%</td><td>0.280856</td><td>12</td><td>0.00170</td></tr><tr><td>13DC13_4_2</td><td>538</td><td>381</td><td>601</td><td>0.53</td><td>3455</td><td>24</td><td>3%</td><td>0.280856</td><td>12</td><td>0.00170</td></tr><tr><td>13DC13_5a_1</td><td>2772</td><td>123</td><td>2057</td><td>0.11</td><td>3116</td><td>25</td><td>14%</td><td>0.280873</td><td>11</td><td>0.00191</td></tr><tr><td>13DC13_5a_2</td><td>3668</td><td>459</td><td>3205</td><td>0.14</td><td>3163</td><td>25</td><td>2%</td><td>0.280873</td><td>11</td><td>0.00191</td></tr><tr><td>13DC13_5b_1</td><td>1395</td><td>80</td><td>1044</td><td>0.08</td><td>3276</td><td>15</td><td>24%</td><td>0.280837</td><td>16</td><td>0.00182</td></tr><tr><td>13DC13_5b_2</td><td>680</td><td>28</td><td>694</td><td>0.05</td><td>3355</td><td>18</td><td>-7%</td><td>0.280837</td><td>16</td><td>0.00182</td></tr><tr><td>13DC13_6a</td><td>1380</td><td>25</td><td>700</td><td>0.02</td><td>3133</td><td>15</td><td>40%</td><td>0.280893</td><td>16</td><td>0.00206</td></tr><tr><td>13DC13_6b</td><td>122</td><td>83</td><td>154</td><td>0.58</td><td>3320</td><td>16</td><td>-14%</td><td>0.280856</td><td>15</td><td>0.00167</td></tr><tr><td>13DC13_6c</td><td>2410</td><td>55</td><td>933</td><td>0.03</td><td>3007</td><td>14</td><td>52%</td><td>0.280926</td><td>14</td><td>0.00284</td></tr><tr><td>13DC13_7a</td><td>2222</td><td>342</td><td>801</td><td>0.11</td><td>2964</td><td>17</td><td>54%</td><td>0.280899</td><td>26</td><td>0.00256</td></tr><tr><td>13DC13_7b</td><td>576</td><td>512</td><td>633</td><td>0.66</td><td>3441</td><td>16</td><td>5%</td><td>0.280948</td><td>18</td><td>0.00348</td></tr><tr><td>13DC13_8a</td><td>2097</td><td>560</td><td>497</td><td>1.22</td><td>2836</td><td>20</td><td>80%</td><td>0.280872</td><td>33</td><td>0.00186</td></tr><tr><td>13DC13_8b</td><td>615</td><td>259</td><td>268</td><td>1.21</td><td>3079</td><td>22</td><td>29%</td><td>0.280836</td><td>26</td><td>0.00186</td></tr><tr><td>13DC13_11a</td><td>265</td><td>170</td><td>254</td><td>0.79</td><td>3354</td><td>18</td><td>14%</td><td>0.280888</td><td>15</td><td>0.00234</td></tr><tr><td>13DC13_11b</td><td>225</td><td>156</td><td>234</td><td>0.82</td><td>3356</td><td>17</td><td>5%</td><td>0.280912</td><td>16</td><td>0.00283</td></tr><tr><td>13DC13_12a</td><td>291</td><td>101</td><td>299</td><td>0.32</td><td>3414</td><td>23</td><td>0%</td><td>0.280929</td><td>15</td><td>0.00105</td></tr><tr><td>13DC13_12b</td><td>232</td><td>12</td><td>191</td><td>0.05</td><td>3179</td><td>11</td><td>3%</td><td>0.280864</td><td>9</td><td>0.00069</td></tr><tr><td colspan="11"><strong>Biotite-rich enclave</strong></td></tr><tr><td>13DC15_1a</td><td>241</td><td>75</td><td>240</td><td>0.43</td><td>3473</td><td>21</td><td>2%</td><td>0.280571</td><td>21</td><td>0.00140</td></tr><tr><td>13DC15_1b</td><td>494</td><td>86</td><td>314</td><td>0.18</td><td>2973</td><td>30</td><td>23%</td><td>0.280548</td><td>11</td><td>0.00108</td></tr><tr><td>13DC15_2a</td><td>293</td><td>177</td><td>320</td><td>0.47</td><td>3603</td><td>23</td><td>9%</td><td>0.280450</td><td>17</td><td>0.00109</td></tr><tr><td>13DC15_2b</td><td>315</td><td>191</td><td>336</td><td>0.54</td><td>3610</td><td>23</td><td>11%</td><td>0.280475</td><td>20</td><td>0.00146</td></tr></tbody></table>
S and LA-MC-ICP-MS

<table><thead><tr><th>2 σ<br>(x10<sup>-5</sup>)</th><th><sup>176</sup>Hf/<sup>177</sup>Hf<sub>in</sub></th><th>2 σ<br>(x10<sup>-6</sup>)</th><th>ε<sub>Hf in</sub></th><th>2 σ</th></tr></thead><tbody><tr><td>13</td><td>0.280746</td><td>20 -0.3</td><td>0.7</td><td></td></tr><tr><td>21</td><td>0.280699</td><td>26 -2.9</td><td>0.9</td><td></td></tr><tr><td>14</td><td>0.280768</td><td>31 -10</td><td>1.1</td><td></td></tr><tr><td>8</td><td>0.280693</td><td>24 -9.8</td><td>0.9</td><td></td></tr><tr><td>9</td><td>0.280635</td><td>22 +2.3</td><td>0.8</td><td></td></tr><tr><td>9</td><td>0.280634</td><td>22 +2.4</td><td>0.8</td><td></td></tr><tr><td>5</td><td>0.280613</td><td>16 +1.3</td><td>0.6</td><td></td></tr><tr><td>7</td><td>0.280635</td><td>18 +2.3</td><td>0.6</td><td></td></tr><tr><td>3</td><td>0.280625</td><td>15 +1.9</td><td>0.5</td><td></td></tr><tr><td>20</td><td>0.280638</td><td>28 +2.2</td><td>1.0</td><td></td></tr><tr><td>9</td><td>0.280636</td><td>14 +2.3</td><td>0.5</td><td></td></tr><tr><td>14</td><td>0.280632</td><td>27 -9.1</td><td>1.0</td><td></td></tr><tr><td>21</td><td>0.280650</td><td>27 -3.6</td><td>1.0</td><td></td></tr><tr><td>12</td><td>0.280626</td><td>21 -0.1</td><td>0.8</td><td></td></tr><tr><td>5</td><td>0.280577</td><td>33 -0.9</td><td>1.2</td><td></td></tr><tr><td>10</td><td>0.280678</td><td>44 +4.1</td><td>1.6</td><td></td></tr><tr><td>6</td><td>0.280631</td><td>21 -7.1</td><td>0.8</td><td></td></tr><tr><td>31</td><td>0.280591</td><td>42 +0.2</td><td>1.5</td><td></td></tr><tr><td>20</td><td>0.280590</td><td>33 -0.4</td><td>1.2</td><td></td></tr><tr><td>23</td><td>0.280678</td><td>29 -7.2</td><td>1.0</td><td></td></tr><tr><td>23</td><td>0.280661</td><td>22 +0.8</td><td>0.8</td><td></td></tr><tr><td>10</td><td>0.280623</td><td>17 -2.3</td><td>0.6</td><td></td></tr><tr><td>15</td><td>0.280600</td><td>17 -0.1</td><td>0.6</td><td></td></tr><tr><td>9</td><td>0.280769</td><td>22 +3.9</td><td>0.8</td><td></td></tr><tr><td>6</td><td>0.280797</td><td>25 +2.7</td><td>0.9</td><td></td></tr><tr><td>6</td><td>0.280744</td><td>14 +6.5</td><td>0.5</td><td></td></tr><tr><td>6</td><td>0.280743</td><td>14 +7.2</td><td>0.5</td><td></td></tr><tr><td>4</td><td>0.280758</td><td>13 -0.4</td><td>0.5</td><td></td></tr><tr><td>4</td><td>0.280756</td><td>13 +0.7</td><td>0.5</td><td></td></tr><tr><td>7</td><td>0.280722</td><td>18 +2.2</td><td>0.6</td><td></td></tr><tr><td>7</td><td>0.280719</td><td>18 +4.0</td><td>0.6</td><td></td></tr><tr><td>4</td><td>0.280769</td><td>17 +0.4</td><td>0.6</td><td></td></tr><tr><td>6</td><td>0.280749</td><td>17 +4.2</td><td>0.6</td><td></td></tr><tr><td>7</td><td>0.280762</td><td>16 -2.8</td><td>0.6</td><td></td></tr><tr><td>13</td><td>0.280753</td><td>27 -4.2</td><td>1.0</td><td></td></tr><tr><td>17</td><td>0.280717</td><td>22 +5.9</td><td>0.8</td><td></td></tr><tr><td>7</td><td>0.280771</td><td>34 -6.6</td><td>1.2</td><td></td></tr><tr><td>7</td><td>0.280726</td><td>27 -2.4</td><td>1.0</td><td></td></tr><tr><td>7</td><td>0.280736</td><td>17 +4.6</td><td>0.6</td><td></td></tr><tr><td>7</td><td>0.280730</td><td>17 +4.3</td><td>0.6</td><td></td></tr><tr><td>3</td><td>0.280860</td><td>16 +10.4</td><td>0.6</td><td></td></tr><tr><td>3</td><td>0.280822</td><td>11 +3.4</td><td>0.4</td><td></td></tr><tr><td>6</td><td>0.280477</td><td>22 -1.8</td><td>0.8</td><td></td></tr><tr><td>2</td><td>0.280487</td><td>13 -13.4</td><td>0.5</td><td></td></tr><tr><td>9</td><td>0.280374</td><td>19 -2.4</td><td>0.7</td><td></td></tr><tr><td>4</td><td>0.280373</td><td>21 -2.3</td><td>0.7</td><td></td></tr></tbody></table>
<table><caption>Table 4. Interpreted U-Pb ages and Lu-Hf isotope systematics for Indian zircons analyzed here</caption><thead><tr><th>Sample</th><th>Age (Ma)</th><th>2σ</th><th><sup>176</sup>Hf/<sup>177</sup>Hf<sub>in</sub></th><th>2 σ</th><th>ε<sub>Hf in</sub></th><th>2 σ</th></tr></thead><tbody><tr><td>Granitic gneiss (13DC12)</td><td>3410.8</td><td>3.6</td><td>0.280631</td><td>0.000018</td><td>+2.2</td><td>0.6</td></tr><tr><td colspan="7"><strong>Trondhjemitic gneiss (13DC13)</strong></td></tr><tr><td>Zircon #4 (group 1)</td><td>3468</td><td>41</td><td>0.280742</td><td>0.000014</td><td>+7.5</td><td>0.5</td></tr><tr><td>Zircon #7 (group 1)</td><td>3456</td><td>20</td><td>0.280721</td><td>0.000017</td><td>+6.4</td><td>0.6</td></tr><tr><td>Zircon #12a (group 1)</td><td>3414</td><td>23</td><td>0.280860</td><td>0.000016</td><td>+10.4</td><td>0.6</td></tr><tr><td>Zircon #3 (group 2)</td><td>3359</td><td>110</td><td>0.280778</td><td>0.000016</td><td>+6.1</td><td>0.6</td></tr><tr><td>Zircon #11 (group 2)</td><td>3356</td><td>25</td><td>0.280733</td><td>0.000012</td><td>+4.5</td><td>0.4</td></tr><tr><td>Zircon #5b (group 2)</td><td>3342</td><td>19</td><td>0.280720</td><td>0.000018</td><td>+3.7</td><td>0.6</td></tr><tr><td>Zircon #6 (group 3)</td><td>3295</td><td>18</td><td>0.280752</td><td>0.000010</td><td>+3.7</td><td>0.4</td></tr><tr><td>Zircon #5a (group 4)</td><td>3170</td><td>32</td><td>0.280756</td><td>0.000013</td><td>+0.8</td><td>0.5</td></tr><tr><td>Zircon #12b (group 4)</td><td>3179</td><td>11</td><td>0.280822</td><td>0.000011</td><td>+3.4</td><td>0.4</td></tr><tr><td>Zircon #8 (group 5)</td><td>3101</td><td>25</td><td>0.280739</td><td>0.000021</td><td>-1.4</td><td>0.7</td></tr><tr><td colspan="7"><strong>Biotite-rich enclave (13DC15)</strong></td></tr><tr><td>Zircon #1</td><td>3499</td><td>29</td><td>0.280476</td><td>0.000011</td><td>-1.3</td><td>0.4</td></tr><tr><td>Zircon #2</td><td>3607</td><td>16</td><td>0.280374</td><td>0.000014</td><td>-2.3</td><td>0.5</td></tr></tbody></table>
3in
<figure><img src="image_19.png" /></figure>

<figure><img src="image_20.png" /></figure>
Deviation from accepted ¹⁷⁶Hf/¹⁷⁷Hf (t) in epsilon units

<figure><img src="image_21.png" /></figure>

<figure><img src="image_22.png" /></figure>

<figure><img src="image_23.png" /></figure>

<figure><img src="image_24.png" /><figcaption>Figure S2</figcaption></figure>
<figure><img src="image_25.png" /><figcaption>Figure S3</figcaption></figure>
<figure><img src="image_26.png" /></figure>
<figure><img src="image_27.png" /></figure>

<figure><img src="image_28.png" /><figcaption>Figure S5</figcaption></figure>
<figure><img src="image_29.png" /><figcaption>Figure S6</figcaption></figure>
<table><caption>Table S1. Major and minor oxide abundances for the orthogneisses analyzed in this study</caption><thead><tr><th></th><th>13DC12</th><th>13DC13</th></tr></thead><tbody><tr><td>SiO2</td><td>74.01</td><td>72.57</td></tr><tr><td>TiO2</td><td>0.11</td><td>0.27</td></tr><tr><td>Al2O3</td><td>13.85</td><td>15.04</td></tr><tr><td>Fe2O3</td><td>1.47</td><td>1.69</td></tr><tr><td>MnO</td><td>0.02</td><td>0.02</td></tr><tr><td>MgO</td><td>0.19</td><td>0.50</td></tr><tr><td>CaO</td><td>0.95</td><td>1.82</td></tr><tr><td>Na2O</td><td>3.94</td><td>4.89</td></tr><tr><td>K2O</td><td>4.31</td><td>2.54</td></tr><tr><td>P2O5</td><td>0.11</td><td>0.08</td></tr><tr><td>Ba</td><td>0.048</td><td>0.051</td></tr><tr><td>Sr</td><td>0.009</td><td>0.041</td></tr><tr><td>L.O.I.</td><td>0.83</td><td>0.55</td></tr><tr><td>Total</td><td>99.85</td><td>100.06</td></tr><tr><td>Or</td><td>0.41</td><td>0.24</td></tr><tr><td>Ab</td><td>0.53</td><td>0.64</td></tr><tr><td>An</td><td>0.06</td><td>0.12</td></tr><tr><td>A/(CNK)</td><td>1.1</td><td>1.1</td></tr><tr><td>A/(NK)</td><td>1.2</td><td>1.4</td></tr></tbody></table>
<table><caption>Table S2. LA-ICP-MS and LA-MC-ICP-MS operating conditions</caption><thead><tr><th></th><th>U-Pb geochronology</th><th>Lu-Hf isotope system</th></tr></thead><tbody><tr><td><strong>Analysis</strong></td><td></td><td></td></tr><tr><td><strong>Laboratory</strong></td><td></td><td></td></tr><tr><td>ICP-MS model</td><td>University of New Hampshire</td><td>Université Blaise Pascal</td></tr><tr><td>Forward Power</td><td>Nu Instruments AttoM</td><td>Thermo Neptune +</td></tr><tr><td>Auxiliary gas (Ar)</td><td>1300 W</td><td>1200 W</td></tr><tr><td>Ar sample</td><td>~0.8 l/min</td><td>0.66 l/min</td></tr><tr><td>Oxide ThO/Th</td><td>~0.7 l/min</td><td>0.86 l/min</td></tr><tr><td>Additional gas</td><td>~0.5%</td><td>-</td></tr><tr><td>Additional gas flow</td><td>-</td><td>N2</td></tr><tr><td></td><td>-</td><td>4.5 ml/min</td></tr><tr><td><strong>Laser model</strong></td><td></td><td></td></tr><tr><td>Wavelength</td><td>New Wave Research UP-213</td><td>Resonetics Resolution M-50</td></tr><tr><td>Pulse duration</td><td>213 nm</td><td>193 nm</td></tr><tr><td>Energy</td><td>&lt;4 ns</td><td>&lt;4 ns</td></tr><tr><td>Fluence</td><td>50% / ~0.07 mJ</td><td>~3.2 mJ</td></tr><tr><td>Frequency</td><td>9-10 J/cm²</td><td>~3.8 J/cm²</td></tr><tr><td>Spot size</td><td>5 Hz</td><td>6 Hz</td></tr><tr><td>Carrier gas</td><td>30 µm</td><td>40 µm</td></tr><tr><td>Carrier gas flow</td><td>He</td><td>He</td></tr><tr><td></td><td>~0.8 l/min</td><td>0.7 l/min</td></tr><tr><td><strong>Data acquisition</strong></td><td></td><td></td></tr><tr><td>Protocol</td><td>Time resolved analysis</td><td>Time resolved analysis</td></tr><tr><td>Scanning mode</td><td>Peak-jumping</td><td>Static multi-collection</td></tr><tr><td>Dwell time per isotope</td><td>4 ms</td><td>1s</td></tr><tr><td>Sweeps per cycle</td><td>10</td><td>-</td></tr><tr><td>Dead-time correction</td><td>14 ns</td><td>-</td></tr><tr><td>Settling time</td><td>20 µs</td><td>-</td></tr><tr><td>Background counting time</td><td>30 s</td><td>20s</td></tr><tr><td>Sample measurement time</td><td>60 s</td><td>50s</td></tr><tr><td>Measurement type</td><td>Standard bracketing</td><td>Internal normalization</td></tr><tr><td>External standard</td><td>AS3, 91500</td><td>91500, Mud Tank, Plešovice, R33</td></tr></tbody></table>
<table><caption>Table S3. U-Pb isotope results for the zircon standard 91500 analyzed by LA-ICP-MS.</caption><thead><tr><th rowspan="2">Sample name</th><th rowspan="2">%<sup>206</sup>Pb<sub>rad</sub></th><th colspan="4">Isotope Ratio</th></tr><tr><th><sup>207</sup>Pb/<sup>235</sup>U</th><th>2 σ</th><th><sup>206</sup>Pb/<sup>238</sup>U</th><th>2 σ</th></tr></thead><tbody><tr><td><strong>91500</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>91500_1</td><td>99.05</td><td>1.666</td><td>0.050</td><td>0.162</td><td>0.004</td></tr><tr><td>91500_3</td><td>99.67</td><td>1.765</td><td>0.042</td><td>0.171</td><td>0.004</td></tr><tr><td>91500_5</td><td>99.61</td><td>1.792</td><td>0.072</td><td>0.174</td><td>0.007</td></tr><tr><td>91500_6</td><td>99.23</td><td>1.813</td><td>0.061</td><td>0.175</td><td>0.006</td></tr><tr><td>91500_7</td><td>99.68</td><td>1.890</td><td>0.041</td><td>0.183</td><td>0.003</td></tr><tr><td>91500_8</td><td>98.94</td><td>1.802</td><td>0.072</td><td>0.174</td><td>0.007</td></tr><tr><td>91500_9</td><td>98.92</td><td>1.847</td><td>0.036</td><td>0.180</td><td>0.003</td></tr><tr><td>91500_10</td><td>99.44</td><td>1.847</td><td>0.051</td><td>0.179</td><td>0.004</td></tr><tr><td>91500_11</td><td>99.49</td><td>1.843</td><td>0.083</td><td>0.179</td><td>0.008</td></tr><tr><td>91500_12</td><td>99.75</td><td>1.846</td><td>0.183</td><td>0.180</td><td>0.018</td></tr></tbody></table>
<table><thead><tr><th colspan="4">ios</th><th colspan="4">Ages (N)</th></tr><tr><th><sup>207</sup>Pb/<sup>206</sup>Pb</th><th>2 σ</th><th><sup>208</sup>Pb/<sup>206</sup>Pb</th><th>2 σ</th><th><sup>232</sup>Th/<sup>238</sup>U<sub>C</sub></th><th>2 σ</th><th><sup>207</sup>Pb/<sup>235</sup>U</th><th>2 σ</th><th><sup>206</sup>Pb/<sup>238</sup>U</th></tr></thead><tbody><tr><td>0.0746 0.0009</td><td></td><td>0.1099 0.0025</td><td></td><td>0.365 0.009</td><td></td><td>996 19</td><td></td><td>968</td></tr><tr><td>0.0750 0.0007</td><td></td><td>0.1112 0.0023</td><td></td><td>0.369 0.008</td><td></td><td>1033 15</td><td></td><td>1016</td></tr><tr><td>0.0746 0.0007</td><td></td><td>0.1112 0.0020</td><td></td><td>0.369 0.008</td><td></td><td>1043 26</td><td></td><td>1036</td></tr><tr><td>0.0750 0.0008</td><td></td><td>0.1112 0.0025</td><td></td><td>0.369 0.009</td><td></td><td>1050 22</td><td></td><td>1041</td></tr><tr><td>0.0748 0.0009</td><td></td><td>0.1112 0.0028</td><td></td><td>0.369 0.010</td><td></td><td>1077 14</td><td></td><td>1084</td></tr><tr><td>0.0749 0.0008</td><td></td><td>0.1094 0.0030</td><td></td><td>0.363 0.011</td><td></td><td>1046 26</td><td></td><td>1036</td></tr><tr><td>0.0743 0.0010</td><td></td><td>0.1118 0.0035</td><td></td><td>0.371 0.013</td><td></td><td>1062 13</td><td></td><td>1069</td></tr><tr><td>0.0747 0.0011</td><td></td><td>0.1106 0.0034</td><td></td><td>0.367 0.013</td><td></td><td>1062 18</td><td></td><td>1063</td></tr><tr><td>0.0747 0.0011</td><td></td><td>0.1125 0.0042</td><td></td><td>0.373 0.015</td><td></td><td>1061 29</td><td></td><td>1061</td></tr><tr><td>0.0745 0.0009</td><td></td><td>0.1106 0.0025</td><td></td><td>0.367 0.009</td><td></td><td>1062 63</td><td></td><td>1065</td></tr></tbody><tfoot><tr><td colspan="4">Average</td><td>0.37</td><td>0.01</td><td colspan="3"></td></tr></tfoot></table>

0.344 0.001 Wiedenbeck et al., 1995

0.38 0.09 Wiedenbeck et al., 2004
<table><thead><tr><th colspan="4">1a)</th><th colspan="6">Semi-quantitative estimates</th></tr><tr><th>2 σ</th><th><sup>207</sup>Pb/<sup>206</sup>Pb</th><th>2 σ</th><th>Discordance</th><th>Pb (ppm)</th><th>2 σ</th><th>U (ppm)</th><th>2 σ</th><th>Th (ppm)</th><th>2 σ</th></tr></thead><tbody><tr><td>25</td><td>1057</td><td>23</td><td>9%</td><td>9.0</td><td>2.0</td><td>42.4</td><td>9.6</td><td>13.0</td><td>1.7</td></tr><tr><td>21</td><td>1070</td><td>18</td><td>5%</td><td>13.2</td><td>2.4</td><td>59.7</td><td>7.9</td><td>21.0</td><td>2.8</td></tr><tr><td>38</td><td>1057</td><td>19</td><td>2%</td><td>19.7</td><td>1.7</td><td>84.5</td><td>5.8</td><td>34.6</td><td>1.1</td></tr><tr><td>31</td><td>1069</td><td>20</td><td>3%</td><td>11.9</td><td>0.8</td><td>52.5</td><td>6.2</td><td>16.0</td><td>0.9</td></tr><tr><td>18</td><td>1063</td><td>24</td><td>-2%</td><td>17.4</td><td>0.9</td><td>72.1</td><td>3.3</td><td>26.8</td><td>0.8</td></tr><tr><td>37</td><td>1067</td><td>23</td><td>3%</td><td>15.3</td><td>2.6</td><td>68.3</td><td>10.3</td><td>21.1</td><td>2.8</td></tr><tr><td>14</td><td>1049</td><td>26</td><td>-2%</td><td>13.2</td><td>0.9</td><td>56.4</td><td>4.1</td><td>18.6</td><td>1.1</td></tr><tr><td>23</td><td>1061</td><td>30</td><td>0%</td><td>16.0</td><td>2.6</td><td>70.0</td><td>10.0</td><td>21.8</td><td>2.6</td></tr><tr><td>41</td><td>1061</td><td>30</td><td>0%</td><td>17.2</td><td>1.5</td><td>73.2</td><td>5.4</td><td>24.1</td><td>0.9</td></tr><tr><td>97</td><td>1056</td><td>24</td><td>-1%</td><td>14.2</td><td>3.3</td><td>61.1</td><td>11.4</td><td>18.8</td><td>1.7</td></tr></tbody><tfoot><tr><td colspan="4">Average</td><td>14.4</td><td>2.1</td><td>66.3</td><td>7.9</td><td>23.0</td><td>4.5</td></tr></tfoot></table>

15.0 4.0 80.0 16.0 29.9 4.2

Wiedenbeck et al., 2004
<table><caption>Table S4. U-Pb isotope results for Indian zircons analyzed by LA-ICP-MS.</caption><thead><tr><th rowspan="2">Sample name</th><th rowspan="2">%<sup>206</sup>Pb<sub>rad</sub></th><th colspan="6">Isotope Ratios</th></tr><tr><th><sup>207</sup>Pb/<sup>235</sup>U</th><th>2 σ</th><th><sup>206</sup>Pb/<sup>238</sup>U</th><th>2 σ</th><th><sup>207</sup>Pb/<sup>206</sup>Pb</th><th>2 σ</th></tr></thead><tbody><tr><td colspan="9"><strong>Granitic gneiss</strong></td></tr><tr><td>13DC12_1a</td><td>99.3</td><td>9.7</td><td>0.3</td><td>0.289</td><td>0.010</td><td>0.2426</td><td>0.0015</td></tr><tr><td>13DC12_1b</td><td>99.3</td><td>9.8</td><td>0.2</td><td>0.299</td><td>0.005</td><td>0.2369</td><td>0.0022</td></tr><tr><td>13DC12_2a</td><td>99.5</td><td>3.9</td><td>0.2</td><td>0.152</td><td>0.006</td><td>0.1847</td><td>0.0013</td></tr><tr><td>13DC12_2b</td><td>99.2</td><td>5.9</td><td>0.4</td><td>0.214</td><td>0.014</td><td>0.1986</td><td>0.0012</td></tr><tr><td>13DC12_3_1</td><td>99.6</td><td>20.7</td><td>0.5</td><td>0.519</td><td>0.013</td><td>0.2887</td><td>0.0020</td></tr><tr><td>13DC12_3_2</td><td>99.6</td><td>26.1</td><td>0.4</td><td>0.653</td><td>0.009</td><td>0.2898</td><td>0.0023</td></tr><tr><td>13DC12_4</td><td>99.9</td><td>22.5</td><td>3.0</td><td>0.567</td><td>0.077</td><td>0.2872</td><td>0.0012</td></tr><tr><td>13DC12_5a</td><td>99.9</td><td>27.7</td><td>0.7</td><td>0.696</td><td>0.018</td><td>0.2891</td><td>0.0013</td></tr><tr><td>13DC12_5b</td><td>99.9</td><td>27.5</td><td>1.2</td><td>0.692</td><td>0.031</td><td>0.2885</td><td>0.0008</td></tr><tr><td>13DC12_6</td><td>99.8</td><td>17.4</td><td>1.6</td><td>0.439</td><td>0.040</td><td>0.2873</td><td>0.0018</td></tr><tr><td>13DC12_7</td><td>99.9</td><td>20.4</td><td>1.8</td><td>0.513</td><td>0.046</td><td>0.2882</td><td>0.0011</td></tr><tr><td>13DC12_8a</td><td>98.1</td><td>6.5</td><td>0.3</td><td>0.219</td><td>0.008</td><td>0.2143</td><td>0.0016</td></tr><tr><td>13DC12_8b</td><td>99.7</td><td>10.5</td><td>0.4</td><td>0.312</td><td>0.011</td><td>0.2435</td><td>0.0031</td></tr><tr><td>13DC12_9a</td><td>99.4</td><td>17.1</td><td>0.7</td><td>0.453</td><td>0.018</td><td>0.2732</td><td>0.0012</td></tr><tr><td>13DC12_9b</td><td>99.9</td><td>23.5</td><td>1.8</td><td>0.608</td><td>0.045</td><td>0.2803</td><td>0.0011</td></tr><tr><td>13DC12_10a</td><td>99.8</td><td>21.2</td><td>1.1</td><td>0.527</td><td>0.027</td><td>0.2913</td><td>0.0034</td></tr><tr><td>13DC12_10b</td><td>98.9</td><td>7.0</td><td>0.4</td><td>0.224</td><td>0.011</td><td>0.2261</td><td>0.0047</td></tr><tr><td>13DC12_11a</td><td>99.3</td><td>18.1</td><td>1.0</td><td>0.462</td><td>0.026</td><td>0.2846</td><td>0.0028</td></tr><tr><td>13DC12_11b</td><td>99.5</td><td>16.2</td><td>1.1</td><td>0.418</td><td>0.027</td><td>0.2805</td><td>0.0038</td></tr><tr><td>13DC12_12a</td><td>99.3</td><td>7.2</td><td>0.3</td><td>0.241</td><td>0.009</td><td>0.2154</td><td>0.0021</td></tr><tr><td>13DC12_12b</td><td>99.8</td><td>17.9</td><td>0.5</td><td>0.481</td><td>0.011</td><td>0.2708</td><td>0.0026</td></tr><tr><td>13DC12_13a</td><td>99.5</td><td>13.2</td><td>0.5</td><td>0.370</td><td>0.013</td><td>0.2581</td><td>0.0023</td></tr><tr><td>13DC12_13b</td><td>99.9</td><td>20.2</td><td>1.4</td><td>0.522</td><td>0.035</td><td>0.2803</td><td>0.0026</td></tr><tr><td colspan="9"><strong>Trondhjemitic gneiss</strong></td></tr><tr><td>13DC13_3a</td><td>99.9</td><td>22.9</td><td>0.7</td><td>0.625</td><td>0.019</td><td>0.2652</td><td>0.0032</td></tr><tr><td>13DC13_3b</td><td>99.9</td><td>19.8</td><td>0.8</td><td>0.573</td><td>0.022</td><td>0.2504</td><td>0.0022</td></tr><tr><td>13DC13_4_1</td><td>99.9</td><td>25.4</td><td>0.7</td><td>0.633</td><td>0.016</td><td>0.2911</td><td>0.0032</td></tr><tr><td>13DC13_4_2</td><td>99.9</td><td>28.2</td><td>0.7</td><td>0.687</td><td>0.014</td><td>0.2971</td><td>0.0047</td></tr><tr><td>13DC13_5a_1</td><td>99.6</td><td>17.6</td><td>0.6</td><td>0.534</td><td>0.017</td><td>0.2394</td><td>0.0038</td></tr><tr><td>13DC13_5a_2</td><td>99.6</td><td>21.1</td><td>0.5</td><td>0.620</td><td>0.012</td><td>0.2466</td><td>0.0039</td></tr><tr><td>13DC13_5b_1</td><td>99.8</td><td>18.3</td><td>0.6</td><td>0.502</td><td>0.016</td><td>0.2649</td><td>0.0025</td></tr><tr><td>13DC13_5b_2</td><td>99.9</td><td>28.1</td><td>2.0</td><td>0.730</td><td>0.051</td><td>0.2786</td><td>0.0032</td></tr><tr><td>13DC13_6a</td><td>99.9</td><td>12.5</td><td>0.6</td><td>0.373</td><td>0.018</td><td>0.2420</td><td>0.0022</td></tr><tr><td>13DC13_6b</td><td>99.9</td><td>28.9</td><td>1.7</td><td>0.769</td><td>0.044</td><td>0.2725</td><td>0.0029</td></tr><tr><td>13DC13_6c</td><td>99.9</td><td>8.8</td><td>0.4</td><td>0.285</td><td>0.013</td><td>0.2236</td><td>0.0020</td></tr><tr><td>13DC13_7a_1</td><td>99.8</td><td>8.1</td><td>0.7</td><td>0.270</td><td>0.023</td><td>0.2177</td><td>0.0023</td></tr><tr><td>13DC13_7b</td><td>99.9</td><td>27.2</td><td>0.8</td><td>0.671</td><td>0.019</td><td>0.2944</td><td>0.0031</td></tr><tr><td>13DC13_8a</td><td>98.7</td><td>3.0</td><td>0.4</td><td>0.109</td><td>0.016</td><td>0.2012</td><td>0.0025</td></tr><tr><td>13DC13_8b</td><td>98.9</td><td>13.9</td><td>1.1</td><td>0.432</td><td>0.033</td><td>0.2339</td><td>0.0033</td></tr><tr><td>13DC13_11a</td><td>99.9</td><td>22.6</td><td>0.5</td><td>0.587</td><td>0.012</td><td>0.2785</td><td>0.0032</td></tr><tr><td>13DC13_11b</td><td>99.9</td><td>25.0</td><td>0.4</td><td>0.650</td><td>0.007</td><td>0.2787</td><td>0.0030</td></tr><tr><td>13DC13_12a</td><td>99.9</td><td>27.9</td><td>0.8</td><td>0.700</td><td>0.018</td><td>0.2894</td><td>0.0043</td></tr><tr><td>13DC13_12b</td><td>99.9</td><td>21.1</td><td>0.6</td><td>0.615</td><td>0.015</td><td>0.2491</td><td>0.0018</td></tr><tr><td colspan="9"><strong>Biotite-rich enclave</strong></td></tr><tr><td>13DC15_1a</td><td>99.9</td><td>28.9</td><td>0.7</td><td>0.697</td><td>0.015</td><td>0.3006</td><td>0.0042</td></tr><tr><td>13DC15_1b</td><td>99.2</td><td>13.7</td><td>0.7</td><td>0.454</td><td>0.022</td><td>0.2189</td><td>0.0041</td></tr><tr><td>13DC15_2a</td><td>99.9</td><td>30.7</td><td>1.2</td><td>0.681</td><td>0.023</td><td>0.3271</td><td>0.0050</td></tr></tbody></table>
13DC15_2b

99.9

30.4

1.2

0.670

0.024

0.3285

0.0050
<table><thead><tr><th colspan="6">Ages (Ma)</th></tr><tr><th><sup>208</sup>Pb/<sup>206</sup>Pb</th><th>2 σ</th><th><sup>232</sup>Th/<sup>238</sup>U</th><th>2 σ</th><th><sup>207</sup>Pb/<sup>235</sup>U</th><th>2 σ</th><th><sup>206</sup>Pb/<sup>238</sup>U</th><th>2 σ</th><th><sup>207</sup>Pb/<sup>206</sup>Pb</th><th>2 σ</th></tr></thead><tbody><tr><td>0.1097</td><td>0.0021</td><td>0.410</td><td>0.008</td><td>2403</td><td>31</td><td>1635</td><td>49</td><td>3137</td><td>10</td></tr><tr><td>0.1171</td><td>0.0026</td><td>0.44</td><td>0.01</td><td>2415</td><td>18</td><td>1689</td><td>26</td><td>3100</td><td>15</td></tr><tr><td>0.1344</td><td>0.0092</td><td>0.49</td><td>0.03</td><td>1609</td><td>33</td><td>913</td><td>35</td><td>2696</td><td>11</td></tr><tr><td>0.1653</td><td>0.0028</td><td>0.61</td><td>0.01</td><td>1955</td><td>54</td><td>1249</td><td>73</td><td>2815</td><td>9</td></tr><tr><td>0.1349</td><td>0.0050</td><td>0.51</td><td>0.02</td><td>3124</td><td>25</td><td>2697</td><td>55</td><td>3411</td><td>11</td></tr><tr><td>0.1603</td><td>0.0037</td><td>0.61</td><td>0.01</td><td>3350</td><td>15</td><td>3240</td><td>35</td><td>3416</td><td>12</td></tr><tr><td>0.1016</td><td>0.0018</td><td>0.39</td><td>0.01</td><td>3204</td><td>123</td><td>2897</td><td>323</td><td>3403</td><td>7</td></tr><tr><td>0.0791</td><td>0.0025</td><td>0.30</td><td>0.01</td><td>3410</td><td>25</td><td>3405</td><td>68</td><td>3413</td><td>7</td></tr><tr><td>0.0802</td><td>0.0022</td><td>0.304</td><td>0.009</td><td>3403</td><td>43</td><td>3392</td><td>118</td><td>3410</td><td>4</td></tr><tr><td>0.1653</td><td>0.0049</td><td>0.63</td><td>0.02</td><td>2957</td><td>85</td><td>2346</td><td>183</td><td>3403</td><td>10</td></tr><tr><td>0.2601</td><td>0.0050</td><td>0.99</td><td>0.02</td><td>3110</td><td>82</td><td>2670</td><td>197</td><td>3408</td><td>6</td></tr><tr><td>0.1918</td><td>0.0047</td><td>0.71</td><td>0.02</td><td>2042</td><td>34</td><td>1277</td><td>45</td><td>2939</td><td>12</td></tr><tr><td>0.1221</td><td>0.0042</td><td>0.46</td><td>0.02</td><td>2478</td><td>35</td><td>1751</td><td>56</td><td>3143</td><td>20</td></tr><tr><td>0.1662</td><td>0.0160</td><td>0.63</td><td>0.06</td><td>2938</td><td>38</td><td>2407</td><td>81</td><td>3324</td><td>7</td></tr><tr><td>0.1274</td><td>0.0047</td><td>0.48</td><td>0.02</td><td>3248</td><td>70</td><td>3063</td><td>185</td><td>3365</td><td>6</td></tr><tr><td>0.1939</td><td>0.0086</td><td>0.74</td><td>0.03</td><td>3146</td><td>49</td><td>2728</td><td>114</td><td>3425</td><td>18</td></tr><tr><td>0.1519</td><td>0.0091</td><td>0.56</td><td>0.04</td><td>2111</td><td>46</td><td>1305</td><td>58</td><td>3024</td><td>33</td></tr><tr><td>0.1673</td><td>0.0060</td><td>0.63</td><td>0.02</td><td>2997</td><td>53</td><td>2449</td><td>115</td><td>3388</td><td>15</td></tr><tr><td>0.1733</td><td>0.0153</td><td>0.66</td><td>0.06</td><td>2886</td><td>61</td><td>2251</td><td>123</td><td>3366</td><td>21</td></tr><tr><td>0.2243</td><td>0.0061</td><td>0.83</td><td>0.02</td><td>2131</td><td>33</td><td>1391</td><td>46</td><td>2947</td><td>16</td></tr><tr><td>0.0337</td><td>0.0025</td><td>0.127</td><td>0.009</td><td>2987</td><td>24</td><td>2531</td><td>49</td><td>3310</td><td>15</td></tr><tr><td>0.0989</td><td>0.0063</td><td>0.37</td><td>0.02</td><td>2691</td><td>33</td><td>2028</td><td>60</td><td>3235</td><td>14</td></tr><tr><td>0.1370</td><td>0.0070</td><td>0.52</td><td>0.03</td><td>3099</td><td>63</td><td>2706</td><td>149</td><td>3365</td><td>15</td></tr><tr><td>0.2704</td><td>0.0086</td><td>1.02</td><td>0.03</td><td>3221</td><td>31</td><td>3130</td><td>75</td><td>3278</td><td>19</td></tr><tr><td>0.2734</td><td>0.0060</td><td>1.02</td><td>0.02</td><td>3082</td><td>37</td><td>2922</td><td>91</td><td>3187</td><td>14</td></tr><tr><td>0.0590</td><td>0.0098</td><td>0.22</td><td>0.04</td><td>3325</td><td>26</td><td>3163</td><td>62</td><td>3424</td><td>17</td></tr><tr><td>0.1390</td><td>0.0048</td><td>0.53</td><td>0.02</td><td>3425</td><td>25</td><td>3373</td><td>53</td><td>3455</td><td>24</td></tr><tr><td>0.0305</td><td>0.0012</td><td>0.114</td><td>0.005</td><td>2969</td><td>33</td><td>2757</td><td>70</td><td>3116</td><td>25</td></tr><tr><td>0.0377</td><td>0.0012</td><td>0.141</td><td>0.005</td><td>3142</td><td>24</td><td>3110</td><td>47</td><td>3163</td><td>25</td></tr><tr><td>0.0205</td><td>0.0014</td><td>0.077</td><td>0.005</td><td>3008</td><td>31</td><td>2624</td><td>68</td><td>3276</td><td>15</td></tr><tr><td>0.0120</td><td>0.0017</td><td>0.045</td><td>0.006</td><td>3421</td><td>67</td><td>3535</td><td>191</td><td>3355</td><td>18</td></tr><tr><td>0.0052</td><td>0.0006</td><td>0.020</td><td>0.002</td><td>2640</td><td>45</td><td>2045</td><td>84</td><td>3133</td><td>15</td></tr><tr><td>0.1528</td><td>0.0061</td><td>0.58</td><td>0.02</td><td>3450</td><td>56</td><td>3678</td><td>163</td><td>3320</td><td>16</td></tr><tr><td>0.0068</td><td>0.0007</td><td>0.025</td><td>0.003</td><td>2314</td><td>40</td><td>1614</td><td>64</td><td>3007</td><td>14</td></tr><tr><td>0.0291</td><td>0.0017</td><td>0.108</td><td>0.006</td><td>2244</td><td>74</td><td>1543</td><td>117</td><td>2964</td><td>17</td></tr><tr><td>0.1744</td><td>0.0042</td><td>0.66</td><td>0.02</td><td>3392</td><td>29</td><td>3310</td><td>72</td><td>3441</td><td>16</td></tr><tr><td>0.3320</td><td>0.0225</td><td>1.22</td><td>0.08</td><td>1414</td><td>106</td><td>667</td><td>93</td><td>2836</td><td>20</td></tr><tr><td>0.3256</td><td>0.0317</td><td>1.21</td><td>0.12</td><td>2745</td><td>70</td><td>2314</td><td>148</td><td>3079</td><td>22</td></tr><tr><td>0.2083</td><td>0.0053</td><td>0.79</td><td>0.02</td><td>3208</td><td>22</td><td>2979</td><td>48</td><td>3354</td><td>18</td></tr><tr><td>0.2180</td><td>0.0053</td><td>0.82</td><td>0.02</td><td>3307</td><td>15</td><td>3228</td><td>27</td><td>3356</td><td>17</td></tr><tr><td>0.0831</td><td>0.0045</td><td>0.32</td><td>0.02</td><td>3416</td><td>29</td><td>3420</td><td>70</td><td>3414</td><td>23</td></tr><tr><td>0.0138</td><td>0.0029</td><td>0.05</td><td>0.01</td><td>3145</td><td>25</td><td>3091</td><td>62</td><td>3179</td><td>11</td></tr><tr><td>0.0491</td><td>0.0027</td><td>0.43</td><td>0.01</td><td>3450</td><td>24</td><td>3410</td><td>56</td><td>3473</td><td>21</td></tr><tr><td>0.1137</td><td>0.0101</td><td>0.18</td><td>0.04</td><td>2729</td><td>48</td><td>2413</td><td>99</td><td>2973</td><td>30</td></tr><tr><td>0.1222</td><td>0.0081</td><td>0.47</td><td>0.03</td><td>3510</td><td>36</td><td>3349</td><td>91</td><td>3603</td><td>23</td></tr></tbody></table>
0.1414 0.0048

0.54 0.02

3498 37

3307 92

3610 23
<table><thead><tr><th rowspan="2">Disc.</th><th colspan="6">Semi-quantitative estimates</th></tr><tr><th>Pb (ppm)</th><th>2 σ</th><th>U (ppm)</th><th>2 σ</th><th>Th (ppm)</th><th>2 σ</th></tr></thead><tbody><tr><td>54%</td><td>561.1</td><td>54.2</td><td>1334.2</td><td>75.5</td><td>257.1</td><td>24.1</td></tr><tr><td>51%</td><td>750.8</td><td>69.0</td><td>1691.0</td><td>97.5</td><td>393.6</td><td>21.5</td></tr><tr><td>71%</td><td>762.7</td><td>58.6</td><td>2836.9</td><td>138.0</td><td>1205.3</td><td>56.3</td></tr><tr><td>61%</td><td>719.5</td><td>82.0</td><td>2072.4</td><td>128.7</td><td>1761.5</td><td>119.7</td></tr><tr><td>26%</td><td>441.7</td><td>31.8</td><td>537.6</td><td>26.3</td><td>201.2</td><td>7.2</td></tr><tr><td>7%</td><td>291.9</td><td>28.6</td><td>259.7</td><td>20.9</td><td>119.2</td><td>6.5</td></tr><tr><td>18%</td><td>229.6</td><td>35.6</td><td>252.7</td><td>25.7</td><td>47.9</td><td>8.1</td></tr><tr><td>0%</td><td>270.3</td><td>24.3</td><td>262.1</td><td>14.3</td><td>79.6</td><td>4.3</td></tr><tr><td>1%</td><td>311.2</td><td>144.1</td><td>301.8</td><td>64.9</td><td>99.1</td><td>35.8</td></tr><tr><td>37%</td><td>994.0</td><td>459.5</td><td>1277.1</td><td>279.2</td><td>1155.2</td><td>416.1</td></tr><tr><td>26%</td><td>503.5</td><td>232.0</td><td>470.9</td><td>100.2</td><td>630.9</td><td>224.8</td></tr><tr><td>62%</td><td>1026.5</td><td>476.1</td><td>2848.9</td><td>611.6</td><td>1453.8</td><td>519.7</td></tr><tr><td>50%</td><td>639.5</td><td>299.2</td><td>1351.8</td><td>293.4</td><td>463.4</td><td>168.2</td></tr><tr><td>33%</td><td>498.3</td><td>58.6</td><td>615.0</td><td>31.8</td><td>659.5</td><td>34.4</td></tr><tr><td>11%</td><td>462.0</td><td>63.7</td><td>455.9</td><td>36.4</td><td>283.8</td><td>24.0</td></tr><tr><td>25%</td><td>519.1</td><td>65.7</td><td>581.2</td><td>30.2</td><td>483.1</td><td>30.4</td></tr><tr><td>63%</td><td>549.7</td><td>70.8</td><td>1523.3</td><td>87.3</td><td>1529.7</td><td>84.0</td></tr><tr><td>33%</td><td>856.2</td><td>118.6</td><td>1088.2</td><td>70.1</td><td>827.2</td><td>53.2</td></tr><tr><td>39%</td><td>804.5</td><td>383.7</td><td>1060.1</td><td>255.7</td><td>802.4</td><td>316.6</td></tr><tr><td>58%</td><td>554.2</td><td>264.1</td><td>1328.0</td><td>317.9</td><td>1141.1</td><td>473.1</td></tr><tr><td>28%</td><td>742.4</td><td>355.2</td><td>1958.5</td><td>473.3</td><td>3333.7</td><td>665.8</td></tr><tr><td>43%</td><td>373.6</td><td>181.5</td><td>640.1</td><td>154.4</td><td>201.4</td><td>81.2</td></tr><tr><td>24%</td><td>217.8</td><td>26.1</td><td>271.2</td><td>28.5</td><td>86.3</td><td>11.8</td></tr><tr><td>6%</td><td>362.9</td><td>36.3</td><td>348.2</td><td>22.4</td><td>291.7</td><td>16.8</td></tr><tr><td>10%</td><td>318.5</td><td>34.0</td><td>341.1</td><td>24.9</td><td>314.0</td><td>17.9</td></tr><tr><td>10%</td><td>454.9</td><td>60.5</td><td>512.0</td><td>16.6</td><td>27.1</td><td>3.4</td></tr><tr><td>3%</td><td>601.3</td><td>127.5</td><td>537.8</td><td>54.1</td><td>380.8</td><td>44.1</td></tr><tr><td>14%</td><td>2056.7</td><td>251.9</td><td>2772.3</td><td>171.0</td><td>123.0</td><td>9.9</td></tr><tr><td>2%</td><td>3204.9</td><td>609.0</td><td>3668.1</td><td>425.6</td><td>459.0</td><td>62.8</td></tr><tr><td>24%</td><td>1043.6</td><td>64.4</td><td>1395.5</td><td>35.8</td><td>80.5</td><td>4.2</td></tr><tr><td>-7%</td><td>693.8</td><td>178.2</td><td>679.7</td><td>34.8</td><td>28.3</td><td>4.5</td></tr><tr><td>40%</td><td>700.3</td><td>67.2</td><td>1380.3</td><td>55.6</td><td>24.8</td><td>1.6</td></tr><tr><td>-14%</td><td>153.6</td><td>20.8</td><td>122.4</td><td>7.6</td><td>83.0</td><td>7.3</td></tr><tr><td>52%</td><td>933.0</td><td>156.1</td><td>2409.8</td><td>204.5</td><td>54.9</td><td>4.3</td></tr><tr><td>54%</td><td>800.6</td><td>416.3</td><td>2221.8</td><td>334.3</td><td>342.3</td><td>35.0</td></tr><tr><td>5%</td><td>633.2</td><td>23.9</td><td>576.3</td><td>13.3</td><td>512.3</td><td>9.6</td></tr><tr><td>80%</td><td>497.2</td><td>163.9</td><td>2097.3</td><td>130.5</td><td>560.3</td><td>34.1</td></tr><tr><td>29%</td><td>267.8</td><td>50.0</td><td>615.1</td><td>65.1</td><td>259.1</td><td>34.6</td></tr><tr><td>14%</td><td>254.4</td><td>37.7</td><td>265.0</td><td>18.6</td><td>169.7</td><td>20.1</td></tr><tr><td>5%</td><td>234.5</td><td>34.5</td><td>224.7</td><td>15.6</td><td>155.7</td><td>18.4</td></tr><tr><td>0%</td><td>299.1</td><td>46.4</td><td>290.7</td><td>21.1</td><td>101.5</td><td>12.7</td></tr><tr><td>3%</td><td>191.0</td><td>11.8</td><td>232.3</td><td>5.1</td><td>12.1</td><td>1.4</td></tr><tr><td>2%</td><td>239.9</td><td>28.6</td><td>240.6</td><td>24.3</td><td>75.1</td><td>9.4</td></tr><tr><td>23%</td><td>313.6</td><td>24.1</td><td>494.5</td><td>20.9</td><td>86.1</td><td>9.8</td></tr><tr><td>9%</td><td>320.1</td><td>18.1</td><td>292.7</td><td>10.4</td><td>177.2</td><td>4.5</td></tr></tbody></table>
11%

336.1

10.8

314.8

7.4

191.2

4.0
<table><caption>Table S5: Lu-Hf isotope results for zircon standards analyzed by LA-MC-ICP-MS</caption><thead><tr><th>Standard name</th><th>Age (Ma)</th><th>176Hf/177Hf 2 ste</th><th>176Lu/177Hf 2 ste</th><th>176Yb/177Hf</th></tr></thead><tbody><tr><td>91500</td><td>1065</td><td>0.282305</td><td>0.000006</td><td>0.000121–0.000381</td><td>0.0036–0.0095</td></tr><tr><td>91500_1</td><td></td><td>0.282305</td><td>0.000016</td><td>0.000418</td><td>0.000001</td><td>0.014910</td></tr><tr><td>91500_2</td><td></td><td>0.282293</td><td>0.000016</td><td>0.000438</td><td>0.000001</td><td>0.015459</td></tr><tr><td>91500_3</td><td></td><td>0.282302</td><td>0.000017</td><td>0.000407</td><td>0.000001</td><td>0.014321</td></tr><tr><td>91500_4</td><td></td><td>0.282299</td><td>0.000018</td><td>0.000409</td><td>0.000001</td><td>0.014367</td></tr><tr><td>91500_5</td><td></td><td>0.282307</td><td>0.000016</td><td>0.000437</td><td>0.000001</td><td>0.015457</td></tr><tr><td>91500_6</td><td></td><td>0.282302</td><td>0.000013</td><td>0.000423</td><td>0.000001</td><td>0.014444</td></tr><tr><td>91500_7</td><td></td><td>0.282305</td><td>0.000018</td><td>0.000420</td><td>0.000001</td><td>0.014222</td></tr><tr><td>91500_8</td><td></td><td>0.282286</td><td>0.000016</td><td>0.000390</td><td>0.000001</td><td>0.013120</td></tr><tr><td>91500_9</td><td></td><td>0.282302</td><td>0.000018</td><td>0.000383</td><td>0.000001</td><td>0.012902</td></tr><tr><td>91500_10</td><td></td><td>0.282286</td><td>0.000014</td><td>0.000356</td><td>0.000000</td><td>0.011996</td></tr><tr><td>91500_11</td><td></td><td>0.282301</td><td>0.000014</td><td>0.000374</td><td>0.000000</td><td>0.012674</td></tr><tr><td>91500_12</td><td></td><td>0.282280</td><td>0.000020</td><td>0.000386</td><td>0.000001</td><td>0.012975</td></tr><tr><td>91500_13</td><td></td><td>0.282309</td><td>0.000019</td><td>0.000390</td><td>0.000001</td><td>0.013130</td></tr><tr><td>91500_14</td><td></td><td>0.282302</td><td>0.000016</td><td>0.000386</td><td>0.000001</td><td>0.012839</td></tr><tr><td>91500_15</td><td></td><td>0.282294</td><td>0.000017</td><td>0.000414</td><td>0.000001</td><td>0.013977</td></tr><tr><td>91500_16</td><td></td><td>0.282315</td><td>0.000014</td><td>0.000405</td><td>0.000001</td><td>0.013517</td></tr><tr><td></td><td>Average</td><td>0.282299</td><td>0.000018</td><td>0.000402</td><td>0.000046</td><td>0.013769</td></tr><tr><td>Mud tank</td><td>570</td><td>0.282507</td><td>0.000006</td><td>0.000042–0.000042</td><td>0.0012</td></tr><tr><td>MudTank_1</td><td></td><td>0.282515</td><td>0.000012</td><td>0.000018</td><td>0.000000</td><td>0.000780</td></tr><tr><td>MudTank_2</td><td></td><td>0.282500</td><td>0.000012</td><td>0.000017</td><td>0.000000</td><td>0.000746</td></tr><tr><td>MudTank_3</td><td></td><td>0.282497</td><td>0.000011</td><td>0.000020</td><td>0.000000</td><td>0.000854</td></tr><tr><td>MudTank_4</td><td></td><td>0.282497</td><td>0.000011</td><td>0.000020</td><td>0.000000</td><td>0.000854</td></tr><tr><td>MudTank_5</td><td></td><td>0.282506</td><td>0.000012</td><td>0.000019</td><td>0.000000</td><td>0.000814</td></tr><tr><td>MudTank_6</td><td></td><td>0.282509</td><td>0.000011</td><td>0.000023</td><td>0.000000</td><td>0.000948</td></tr><tr><td>MudTank_7</td><td></td><td>0.282489</td><td>0.000012</td><td>0.000017</td><td>0.000000</td><td>0.000745</td></tr><tr><td>MudTank_8</td><td></td><td>0.282504</td><td>0.000010</td><td>0.000018</td><td>0.000000</td><td>0.000737</td></tr><tr><td>MudTank_9</td><td></td><td>0.282504</td><td>0.000012</td><td>0.000017</td><td>0.000000</td><td>0.000703</td></tr><tr><td>MudTank_10</td><td></td><td>0.282493</td><td>0.000009</td><td>0.000017</td><td>0.000000</td><td>0.000707</td></tr><tr><td>MudTank_11</td><td></td><td>0.282500</td><td>0.000011</td><td>0.000017</td><td>0.000000</td><td>0.000708</td></tr><tr><td>MudTank_12</td><td></td><td>0.282513</td><td>0.000012</td><td>0.000018</td><td>0.000000</td><td>0.000759</td></tr><tr><td>MudTank_13</td><td></td><td>0.282510</td><td>0.000013</td><td>0.000018</td><td>0.000000</td><td>0.000723</td></tr><tr><td>MudTank_14</td><td></td><td>0.282496</td><td>0.000013</td><td>0.000017</td><td>0.000000</td><td>0.000727</td></tr><tr><td>MudTank_15</td><td></td><td>0.282494</td><td>0.000010</td><td>0.000020</td><td>0.000000</td><td>0.000805</td></tr><tr><td>MudTank_16</td><td></td><td>0.282503</td><td>0.000013</td><td>0.000018</td><td>0.000000</td><td>0.000766</td></tr><tr><td>MudTank_17</td><td></td><td>0.282484</td><td>0.000013</td><td>0.000018</td><td>0.000000</td><td>0.000732</td></tr><tr><td></td><td>Average</td><td>0.282501</td><td>0.000017</td><td>0.000018</td><td>0.000003</td><td>0.000771</td></tr><tr><td>Plešovice</td><td>337</td><td>0.282482</td><td>0.000012</td><td>0.000042–0.000141</td><td>0.0012–0.0041</td></tr><tr><td>Plešovice_gr1_1</td><td></td><td>0.282479</td><td>0.000010</td><td>0.000079</td><td>0.000002</td><td>0.004115</td></tr><tr><td>Plešovice_gr1_2</td><td></td><td>0.282480</td><td>0.000010</td><td>0.000088</td><td>0.000000</td><td>0.004563</td></tr><tr><td>Plešovice_gr1_3</td><td></td><td>0.282476</td><td>0.000010</td><td>0.000085</td><td>0.000001</td><td>0.004391</td></tr><tr><td>Plešovice_gr1_4</td><td></td><td>0.282462</td><td>0.000009</td><td>0.000088</td><td>0.000000</td><td>0.004573</td></tr><tr><td>Plešovice_gr1_5</td><td></td><td>0.282467</td><td>0.000012</td><td>0.000085</td><td>0.000000</td><td>0.004412</td></tr><tr><td>Plešovice_gr1_6</td><td></td><td>0.282470</td><td>0.000012</td><td>0.000106</td><td>0.000000</td><td>0.005312</td></tr><tr><td>Plešovice_gr1_7</td><td></td><td>0.282467</td><td>0.000012</td><td>0.000087</td><td>0.000000</td><td>0.004454</td></tr><tr><td></td><td>Average</td><td>0.282472</td><td>0.000013</td><td>0.000088</td><td>0.000017</td><td>0.004546</td></tr><tr><td>R33</td><td>419</td><td>0.282764</td><td>0.000014</td><td>0.001989–0.001989</td><td>0.052</td></tr></tbody></table>
<table><tr><td>R33_gr1_1</td><td>0.282749</td><td>0.000018</td><td>0.002085</td><td>0.000063</td><td>0.076698</td></tr><tr><td>R33_gr1_2</td><td>0.282755</td><td>0.000013</td><td>0.001832</td><td>0.000091</td><td>0.067295</td></tr><tr><td>R33_gr1_3</td><td>0.282757</td><td>0.000016</td><td>0.001660</td><td>0.000056</td><td>0.059885</td></tr><tr><td>R33_gr1_4</td><td>0.282728</td><td>0.000016</td><td>0.001249</td><td>0.000050</td><td>0.044724</td></tr><tr><td>R33_gr1_5</td><td>0.282740</td><td>0.000012</td><td>0.001351</td><td>0.000011</td><td>0.047085</td></tr><tr><td>R33_gr2_1</td><td>0.282785</td><td>0.000014</td><td>0.003456</td><td>0.000014</td><td>0.120370</td></tr><tr><td>R33_gr2_2</td><td>0.282771</td><td>0.000014</td><td>0.003375</td><td>0.000016</td><td>0.117759</td></tr><tr><td>R33_gr2_3</td><td>0.282785</td><td>0.000012</td><td>0.003821</td><td>0.000033</td><td>0.135503</td></tr><tr><td>R33_gr2_4</td><td>0.282747</td><td>0.000015</td><td>0.002672</td><td>0.000039</td><td>0.094189</td></tr><tr><td>Average</td><td>0.282757</td><td>0.000039</td><td>0.002389</td><td>0.001943</td><td>0.084834</td></tr></table>

<footnote>* Present day value normalized to the respective zircon standard best average ¹⁷⁶Hf/¹⁷⁷Hf as provided by the c</footnote>
<table><thead><tr><th>2 ste</th><th>178Hf/177Hf</th><th>2 ste</th><th>εHf(ref)*</th><th>2 ste</th><th>Reference</th></tr></thead><tbody><tr><td colspan="6" style="text-align: center;">Blichert-Toft (2008)</td></tr><tr><td>0.000109</td><td>1.467259</td><td>0.000047</td><td>0.0</td><td>0.6</td><td></td></tr><tr><td>0.000094</td><td>1.467260</td><td>0.000031</td><td>-0.5</td><td>0.6</td><td></td></tr><tr><td>0.000087</td><td>1.467289</td><td>0.000037</td><td>-0.1</td><td>0.6</td><td></td></tr><tr><td>0.000081</td><td>1.467286</td><td>0.000044</td><td>-0.2</td><td>0.6</td><td></td></tr><tr><td>0.000091</td><td>1.467252</td><td>0.000040</td><td>0.0</td><td>0.6</td><td></td></tr><tr><td>0.000129</td><td>1.467262</td><td>0.000037</td><td>-0.1</td><td>0.5</td><td></td></tr><tr><td>0.000114</td><td>1.467275</td><td>0.000043</td><td>0.0</td><td>0.6</td><td></td></tr><tr><td>0.000103</td><td>1.467261</td><td>0.000032</td><td>-0.7</td><td>0.6</td><td></td></tr><tr><td>0.000095</td><td>1.467261</td><td>0.000042</td><td>-0.1</td><td>0.6</td><td></td></tr><tr><td>0.000101</td><td>1.467288</td><td>0.000032</td><td>-0.6</td><td>0.5</td><td></td></tr><tr><td>0.000095</td><td>1.467239</td><td>0.000038</td><td>-0.1</td><td>0.5</td><td></td></tr><tr><td>0.000116</td><td>1.467256</td><td>0.000040</td><td>-0.9</td><td>0.7</td><td></td></tr><tr><td>0.000093</td><td>1.467282</td><td>0.000035</td><td>0.1</td><td>0.7</td><td></td></tr><tr><td>0.000053</td><td>1.467292</td><td>0.000036</td><td>-0.1</td><td>0.6</td><td></td></tr><tr><td>0.000096</td><td>1.467308</td><td>0.000037</td><td>-0.4</td><td>0.6</td><td></td></tr><tr><td>0.000099</td><td>1.467261</td><td>0.000039</td><td>0.3</td><td>0.5</td><td></td></tr><tr><td>0.002056</td><td>1.467271</td><td>0.000036</td><td>0.4</td><td>0.7</td><td></td></tr></tbody></table>

Woodhead and Hergt (2005)

<table><tr><td>0.000009</td><td>1.467283</td><td>0.000024</td><td>0.3</td><td>0.4</td></tr><tr><td>0.000008</td><td>1.467256</td><td>0.000026</td><td>-0.2</td><td>0.4</td></tr><tr><td>0.000013</td><td>1.467266</td><td>0.000030</td><td>-0.4</td><td>0.4</td></tr><tr><td>0.000013</td><td>1.467266</td><td>0.000030</td><td>-0.4</td><td>0.4</td></tr><tr><td>0.000007</td><td>1.467258</td><td>0.000029</td><td>0.0</td><td>0.4</td></tr><tr><td>0.000006</td><td>1.467275</td><td>0.000021</td><td>0.1</td><td>0.4</td></tr><tr><td>0.000006</td><td>1.467268</td><td>0.000023</td><td>-0.6</td><td>0.4</td></tr><tr><td>0.000007</td><td>1.467276</td><td>0.000025</td><td>-0.1</td><td>0.3</td></tr><tr><td>0.000005</td><td>1.467293</td><td>0.000026</td><td>-0.1</td><td>0.4</td></tr><tr><td>0.000007</td><td>1.467280</td><td>0.000027</td><td>-0.5</td><td>0.3</td></tr><tr><td>0.000006</td><td>1.467272</td><td>0.000025</td><td>-0.2</td><td>0.4</td></tr><tr><td>0.000010</td><td>1.467314</td><td>0.000034</td><td>0.2</td><td>0.4</td></tr><tr><td>0.000005</td><td>1.467279</td><td>0.000027</td><td>0.1</td><td>0.4</td></tr><tr><td>0.000011</td><td>1.467256</td><td>0.000031</td><td>-0.4</td><td>0.5</td></tr><tr><td>0.000005</td><td>1.467266</td><td>0.000032</td><td>-0.5</td><td>0.4</td></tr><tr><td>0.000007</td><td>1.467283</td><td>0.000034</td><td>-0.1</td><td>0.5</td></tr><tr><td>0.000006</td><td>1.467281</td><td>0.000026</td><td>-0.8</td><td>0.4</td></tr><tr><td>0.000132</td><td>1.467275</td><td>0.000029</td><td>-0.2</td><td>0.6</td></tr></table>

Sláma et al. (2008)

<table><tr><td>0.000043</td><td>1.467261</td><td>0.000029</td><td>-0.1</td><td>0.4</td></tr><tr><td>0.000035</td><td>1.467280</td><td>0.000032</td><td>-0.1</td><td>0.4</td></tr><tr><td>0.000100</td><td>1.467276</td><td>0.000021</td><td>-0.2</td><td>0.4</td></tr><tr><td>0.000035</td><td>1.467276</td><td>0.000024</td><td>-0.7</td><td>0.3</td></tr><tr><td>0.000016</td><td>1.467257</td><td>0.000026</td><td>-0.5</td><td>0.4</td></tr><tr><td>0.000048</td><td>1.467278</td><td>0.000026</td><td>-0.4</td><td>0.4</td></tr><tr><td>0.000070</td><td>1.467278</td><td>0.000028</td><td>-0.5</td><td>0.4</td></tr><tr><td>0.000741</td><td>1.467272</td><td>0.000019</td><td>-0.4</td><td>0.5</td></tr></table>

Fisher et al. (2014)
<table><tr><td>0.003340</td><td>1.467262</td><td>0.000031</td><td>-0.6</td><td>0.6</td></tr><tr><td>0.004302</td><td>1.467280</td><td>0.000031</td><td>-0.3</td><td>0.5</td></tr><tr><td>0.001717</td><td>1.467243</td><td>0.000037</td><td>-0.1</td><td>0.6</td></tr><tr><td>0.002176</td><td>1.467269</td><td>0.000025</td><td>-1.1</td><td>0.6</td></tr><tr><td>0.000720</td><td>1.467270</td><td>0.000033</td><td>-0.7</td><td>0.4</td></tr><tr><td>0.000759</td><td>1.467256</td><td>0.000027</td><td>0.3</td><td>0.5</td></tr><tr><td>0.000502</td><td>1.467293</td><td>0.000031</td><td>-0.2</td><td>0.5</td></tr><tr><td>0.000336</td><td>1.467277</td><td>0.000026</td><td>0.2</td><td>0.4</td></tr><tr><td>0.000906</td><td>1.467256</td><td>0.000035</td><td>-0.8</td><td>0.5</td></tr><tr><td>0.067200</td><td>1.467267</td><td>0.000030</td><td>-0.3</td><td>0.9</td></tr></table>

quoted reference
<table><caption>Table S6. Lu-Hf isotope results for Indian zircons analyzed by LA-MC-ICP-MS</caption><thead><tr><th>Name</th><th>Age (Ma)</th><th>2 σ</th><th>Discordance (%)</th><th>176Hf/177Hf</th><th>2 σ</th><th>176Lu/177Hf</th></tr></thead><tbody><tr><td colspan="7"><em>Granitic gneiss</em></td></tr><tr><td>13DC12_1a</td><td>3137</td><td>10</td><td>54%</td><td>0.281023</td><td>0.000018</td><td>0.00460</td></tr><tr><td>13DC12_1b</td><td>3100</td><td>15</td><td>51%</td><td>0.280990</td><td>0.000022</td><td>0.00489</td></tr><tr><td>13DC12_2a</td><td>2696</td><td>11</td><td>71%</td><td>0.281124</td><td>0.000029</td><td>0.00689</td></tr><tr><td>13DC12_2b</td><td>2815</td><td>9</td><td>61%</td><td>0.280890</td><td>0.000023</td><td>0.00365</td></tr><tr><td>13DC12_3</td><td>3411</td><td>11</td><td>26%</td><td>0.280772</td><td>0.000021</td><td>0.00209</td></tr><tr><td>13DC12_3</td><td>3416</td><td>12</td><td>7%</td><td>0.280772</td><td>0.000021</td><td>0.00209</td></tr><tr><td>13DC12_4</td><td>3403</td><td>7</td><td>18%</td><td>0.280723</td><td>0.000015</td><td>0.00167</td></tr><tr><td>13DC12_5a</td><td>3413</td><td>7</td><td>0%</td><td>0.280757</td><td>0.000016</td><td>0.00186</td></tr><tr><td>13DC12_5b</td><td>3410</td><td>4</td><td>1%</td><td>0.280734</td><td>0.000014</td><td>0.00165</td></tr><tr><td>13DC12_6</td><td>3403</td><td>10</td><td>37%</td><td>0.280875</td><td>0.000024</td><td>0.00361</td></tr><tr><td>13DC12_7</td><td>3408</td><td>6</td><td>26%</td><td>0.280766</td><td>0.000012</td><td>0.00198</td></tr><tr><td>13DC12_8a</td><td>2939</td><td>12</td><td>62%</td><td>0.280855</td><td>0.000025</td><td>0.00394</td></tr><tr><td>13DC12_8b</td><td>3143</td><td>20</td><td>50%</td><td>0.281032</td><td>0.000024</td><td>0.00633</td></tr><tr><td>13DC12_9a</td><td>3324</td><td>7</td><td>33%</td><td>0.280767</td><td>0.000019</td><td>0.00219</td></tr><tr><td>13DC12_9b</td><td>3365</td><td>6</td><td>11%</td><td>0.280685</td><td>0.000032</td><td>0.00167</td></tr><tr><td>13DC12_10a</td><td>3425</td><td>18</td><td>25%</td><td>0.280884</td><td>0.000043</td><td>0.00313</td></tr><tr><td>13DC12_10b</td><td>3024</td><td>33</td><td>63%</td><td>0.280816</td><td>0.000020</td><td>0.00317</td></tr><tr><td>13DC12_11a</td><td>3388</td><td>15</td><td>33%</td><td>0.280869</td><td>0.000036</td><td>0.00426</td></tr><tr><td>13DC12_11b</td><td>3366</td><td>21</td><td>39%</td><td>0.280766</td><td>0.000030</td><td>0.00272</td></tr><tr><td>13DC12_12a</td><td>2947</td><td>16</td><td>58%</td><td>0.280886</td><td>0.000025</td><td>0.00369</td></tr><tr><td>13DC12_12b</td><td>3310</td><td>15</td><td>28%</td><td>0.280833</td><td>0.000015</td><td>0.00271</td></tr><tr><td>13DC12_13a</td><td>3235</td><td>14</td><td>43%</td><td>0.280733</td><td>0.000015</td><td>0.00177</td></tr><tr><td>13DC12_13b</td><td>3365</td><td>15</td><td>24%</td><td>0.280739</td><td>0.000013</td><td>0.00214</td></tr><tr><td colspan="7"><em>Trondhjemitic gneiss</em></td></tr><tr><td>13DC13_3a</td><td>3278</td><td>19</td><td>6%</td><td>0.280841</td><td>0.000020</td><td>0.00114</td></tr><tr><td>13DC13_3b</td><td>3187</td><td>14</td><td>10%</td><td>0.280885</td><td>0.000024</td><td>0.00143</td></tr><tr><td>13DC13_4_1</td><td>3424</td><td>17</td><td>10%</td><td>0.280856</td><td>0.000012</td><td>0.00170</td></tr><tr><td>13DC13_4_2</td><td>3455</td><td>24</td><td>3%</td><td>0.280856</td><td>0.000012</td><td>0.00170</td></tr><tr><td>13DC13_5a_1</td><td>3116</td><td>25</td><td>14%</td><td>0.280873</td><td>0.000011</td><td>0.00191</td></tr><tr><td>13DC13_5a_2</td><td>3163</td><td>25</td><td>2%</td><td>0.280873</td><td>0.000011</td><td>0.00191</td></tr><tr><td>13DC13_5b_1</td><td>3276</td><td>15</td><td>24%</td><td>0.280837</td><td>0.000016</td><td>0.00182</td></tr><tr><td>13DC13_5b_2</td><td>3355</td><td>18</td><td>-7%</td><td>0.280837</td><td>0.000016</td><td>0.00182</td></tr><tr><td>13DC13_6a</td><td>3133</td><td>15</td><td>40%</td><td>0.280893</td><td>0.000016</td><td>0.00206</td></tr><tr><td>13DC13_6b</td><td>3320</td><td>16</td><td>-14%</td><td>0.280856</td><td>0.000015</td><td>0.00167</td></tr><tr><td>13DC13_6c</td><td>3007</td><td>14</td><td>52%</td><td>0.280926</td><td>0.000014</td><td>0.00284</td></tr><tr><td>13DC13_7a</td><td>2964</td><td>17</td><td>54%</td><td>0.280899</td><td>0.000026</td><td>0.00256</td></tr><tr><td>13DC13_7b</td><td>3441</td><td>16</td><td>5%</td><td>0.280948</td><td>0.000018</td><td>0.00348</td></tr><tr><td>13DC13_8a</td><td>2836</td><td>20</td><td>80%</td><td>0.280872</td><td>0.000033</td><td>0.00186</td></tr><tr><td>13DC13_8b</td><td>3079</td><td>22</td><td>29%</td><td>0.280836</td><td>0.000026</td><td>0.00186</td></tr><tr><td>13DC13_11a</td><td>3354</td><td>18</td><td>14%</td><td>0.280888</td><td>0.000015</td><td>0.00234</td></tr><tr><td>13DC13_11b</td><td>3356</td><td>17</td><td>5%</td><td>0.280912</td><td>0.000016</td><td>0.00283</td></tr><tr><td>13DC13_12a</td><td>3414</td><td>23</td><td>0%</td><td>0.280929</td><td>0.000015</td><td>0.00105</td></tr><tr><td>13DC13_12b</td><td>3179</td><td>11</td><td>3%</td><td>0.280864</td><td>0.000009</td><td>0.00069</td></tr><tr><td colspan="7"><em>Biotite-rich enclave</em></td></tr><tr><td>13DC15_1a</td><td>3473</td><td>21</td><td>2%</td><td>0.280571</td><td>0.000021</td><td>0.00140</td></tr><tr><td>13DC15_1b</td><td>2973</td><td>30</td><td>23%</td><td>0.280548</td><td>0.000011</td><td>0.00108</td></tr><tr><td>13DC15_2a</td><td>3603</td><td>23</td><td>9%</td><td>0.280450</td><td>0.000017</td><td>0.00109</td></tr></tbody></table>
<table><thead><tr><th>2 σ</th><th>176Yb/177Hf</th><th>2 σ</th><th>178Hf/177Hf</th><th>2 σ</th><th>176Hf/177Hf</th><th>in 2 σ</th></tr></thead><tbody><tr><td>0.00013</td><td>0.1756</td><td>0.0061</td><td>1.46728</td><td>0.00004</td><td>0.280746</td><td>0.000020</td></tr><tr><td>0.00021</td><td>0.1899</td><td>0.0100</td><td>1.46726</td><td>0.00004</td><td>0.280699</td><td>0.000026</td></tr><tr><td>0.00014</td><td>0.2782</td><td>0.0068</td><td>1.46728</td><td>0.00004</td><td>0.280768</td><td>0.000031</td></tr><tr><td>0.00008</td><td>0.1358</td><td>0.0034</td><td>1.46727</td><td>0.00006</td><td>0.280693</td><td>0.000024</td></tr><tr><td>0.00009</td><td>0.0784</td><td>0.0041</td><td>1.46723</td><td>0.00003</td><td>0.280635</td><td>0.000022</td></tr><tr><td>0.00009</td><td>0.0784</td><td>0.0041</td><td>1.46723</td><td>0.00003</td><td>0.280634</td><td>0.000022</td></tr><tr><td>0.00005</td><td>0.0580</td><td>0.0016</td><td>1.46731</td><td>0.00003</td><td>0.280613</td><td>0.000016</td></tr><tr><td>0.00007</td><td>0.0644</td><td>0.0026</td><td>1.46727</td><td>0.00002</td><td>0.280635</td><td>0.000018</td></tr><tr><td>0.00003</td><td>0.0593</td><td>0.0011</td><td>1.46727</td><td>0.00003</td><td>0.280625</td><td>0.000015</td></tr><tr><td>0.00020</td><td>0.1296</td><td>0.0104</td><td>1.46728</td><td>0.00004</td><td>0.280638</td><td>0.000028</td></tr><tr><td>0.00009</td><td>0.0694</td><td>0.0037</td><td>1.46727</td><td>0.00002</td><td>0.280636</td><td>0.000014</td></tr><tr><td>0.00014</td><td>0.1406</td><td>0.0058</td><td>1.46729</td><td>0.00004</td><td>0.280632</td><td>0.000027</td></tr><tr><td>0.00021</td><td>0.2515</td><td>0.0068</td><td>1.46726</td><td>0.00004</td><td>0.280650</td><td>0.000027</td></tr><tr><td>0.00012</td><td>0.0684</td><td>0.0040</td><td>1.46730</td><td>0.00007</td><td>0.280626</td><td>0.000021</td></tr><tr><td>0.00005</td><td>0.0522</td><td>0.0024</td><td>1.46729</td><td>0.00005</td><td>0.280577</td><td>0.000033</td></tr><tr><td>0.00010</td><td>0.1032</td><td>0.0028</td><td>1.46723</td><td>0.00005</td><td>0.280678</td><td>0.000044</td></tr><tr><td>0.00006</td><td>0.1167</td><td>0.0044</td><td>1.46730</td><td>0.00004</td><td>0.280631</td><td>0.000021</td></tr><tr><td>0.00031</td><td>0.1539</td><td>0.0125</td><td>1.46728</td><td>0.00005</td><td>0.280591</td><td>0.000042</td></tr><tr><td>0.00020</td><td>0.0952</td><td>0.0086</td><td>1.46734</td><td>0.00008</td><td>0.280590</td><td>0.000033</td></tr><tr><td>0.00023</td><td>0.1298</td><td>0.0093</td><td>1.46725</td><td>0.00003</td><td>0.280678</td><td>0.000029</td></tr><tr><td>0.00023</td><td>0.0833</td><td>0.0052</td><td>1.46728</td><td>0.00002</td><td>0.280661</td><td>0.000022</td></tr><tr><td>0.00010</td><td>0.0596</td><td>0.0027</td><td>1.46731</td><td>0.00003</td><td>0.280623</td><td>0.000017</td></tr><tr><td>0.00015</td><td>0.0828</td><td>0.0080</td><td>1.46729</td><td>0.00003</td><td>0.280600</td><td>0.000017</td></tr><tr><td>0.00009</td><td>0.0401</td><td>0.0037</td><td>1.46729</td><td>0.00004</td><td>0.280769</td><td>0.000022</td></tr><tr><td>0.00006</td><td>0.0489</td><td>0.0022</td><td>1.46733</td><td>0.00004</td><td>0.280797</td><td>0.000025</td></tr><tr><td>0.00006</td><td>0.0559</td><td>0.0020</td><td>1.46729</td><td>0.00003</td><td>0.280744</td><td>0.000014</td></tr><tr><td>0.00006</td><td>0.0559</td><td>0.0020</td><td>1.46729</td><td>0.00003</td><td>0.280743</td><td>0.000014</td></tr><tr><td>0.00004</td><td>0.0680</td><td>0.0006</td><td>1.46728</td><td>0.00002</td><td>0.280758</td><td>0.000013</td></tr><tr><td>0.00004</td><td>0.0680</td><td>0.0006</td><td>1.46728</td><td>0.00002</td><td>0.280756</td><td>0.000013</td></tr><tr><td>0.00007</td><td>0.0569</td><td>0.0021</td><td>1.46728</td><td>0.00003</td><td>0.280722</td><td>0.000018</td></tr><tr><td>0.00007</td><td>0.0569</td><td>0.0021</td><td>1.46728</td><td>0.00003</td><td>0.280719</td><td>0.000018</td></tr><tr><td>0.00004</td><td>0.0587</td><td>0.0018</td><td>1.46732</td><td>0.00004</td><td>0.280769</td><td>0.000017</td></tr><tr><td>0.00006</td><td>0.0587</td><td>0.0024</td><td>1.46727</td><td>0.00003</td><td>0.280749</td><td>0.000017</td></tr><tr><td>0.00007</td><td>0.0832</td><td>0.0010</td><td>1.46731</td><td>0.00003</td><td>0.280762</td><td>0.000016</td></tr><tr><td>0.00013</td><td>0.0769</td><td>0.0033</td><td>1.46724</td><td>0.00009</td><td>0.280753</td><td>0.000027</td></tr><tr><td>0.00017</td><td>0.1165</td><td>0.0060</td><td>1.46729</td><td>0.00003</td><td>0.280717</td><td>0.000022</td></tr><tr><td>0.00007</td><td>0.0601</td><td>0.0020</td><td>1.46733</td><td>0.00005</td><td>0.280771</td><td>0.000034</td></tr><tr><td>0.00007</td><td>0.0592</td><td>0.0019</td><td>1.46728</td><td>0.00006</td><td>0.280726</td><td>0.000027</td></tr><tr><td>0.00007</td><td>0.0838</td><td>0.0030</td><td>1.46727</td><td>0.00003</td><td>0.280736</td><td>0.000017</td></tr><tr><td>0.00007</td><td>0.0985</td><td>0.0020</td><td>1.46723</td><td>0.00003</td><td>0.280730</td><td>0.000017</td></tr><tr><td>0.00003</td><td>0.0336</td><td>0.0010</td><td>1.46729</td><td>0.00003</td><td>0.280860</td><td>0.000016</td></tr><tr><td>0.00003</td><td>0.0223</td><td>0.0012</td><td>1.46726</td><td>0.00003</td><td>0.280822</td><td>0.000011</td></tr><tr><td>0.00006</td><td>0.0415</td><td>0.0016</td><td>1.46730</td><td>0.00004</td><td>0.280477</td><td>0.000022</td></tr><tr><td>0.00002</td><td>0.0349</td><td>0.0004</td><td>1.46730</td><td>0.00003</td><td>0.280487</td><td>0.000013</td></tr><tr><td>0.00009</td><td>0.0354</td><td>0.0037</td><td>1.46726</td><td>0.00005</td><td>0.280374</td><td>0.000019</td></tr></tbody></table>
0.00004

0.0502

0.0010

1.46726

0.00005

0.280373

0.000021
<table><thead><tr><th>εHf in</th><th>2 σ</th></tr></thead><tbody><tr><td>-0.3</td><td>0.7</td></tr><tr><td>-2.9</td><td>0.9</td></tr><tr><td>-10.0</td><td>1.1</td></tr><tr><td>-9.8</td><td>0.9</td></tr><tr><td>2.3</td><td>0.8</td></tr><tr><td>2.4</td><td>0.8</td></tr><tr><td>1.3</td><td>0.6</td></tr><tr><td>2.3</td><td>0.6</td></tr><tr><td>1.9</td><td>0.5</td></tr><tr><td>2.2</td><td>1.0</td></tr><tr><td>2.3</td><td>0.5</td></tr><tr><td>-9.1</td><td>1.0</td></tr><tr><td>-3.6</td><td>1.0</td></tr><tr><td>-0.1</td><td>0.8</td></tr><tr><td>-0.9</td><td>1.2</td></tr><tr><td>4.1</td><td>1.6</td></tr><tr><td>-7.1</td><td>0.8</td></tr><tr><td>0.2</td><td>1.5</td></tr><tr><td>-0.4</td><td>1.2</td></tr><tr><td>-7.2</td><td>1.0</td></tr><tr><td>0.8</td><td>0.8</td></tr><tr><td>-2.3</td><td>0.6</td></tr><tr><td>-0.1</td><td>0.6</td></tr><tr><td>3.9</td><td>0.8</td></tr><tr><td>2.7</td><td>0.9</td></tr><tr><td>6.5</td><td>0.5</td></tr><tr><td>7.2</td><td>0.5</td></tr><tr><td>-0.4</td><td>0.5</td></tr><tr><td>0.7</td><td>0.5</td></tr><tr><td>2.2</td><td>0.6</td></tr><tr><td>4.0</td><td>0.6</td></tr><tr><td>0.4</td><td>0.6</td></tr><tr><td>4.2</td><td>0.6</td></tr><tr><td>-2.8</td><td>0.6</td></tr><tr><td>-4.2</td><td>1.0</td></tr><tr><td>5.9</td><td>0.8</td></tr><tr><td>-6.6</td><td>1.2</td></tr><tr><td>-2.4</td><td>1.0</td></tr><tr><td>4.6</td><td>0.6</td></tr><tr><td>4.3</td><td>0.6</td></tr><tr><td>10.4</td><td>0.6</td></tr><tr><td>3.4</td><td>0.4</td></tr><tr><td>-1.8</td><td>0.8</td></tr><tr><td>-13.4</td><td>0.5</td></tr><tr><td>-2.4</td><td>0.7</td></tr></tbody></table>
-2.3

0.7