Provenance and sedimentary environments of the ...

7 downloads 0 Views 8MB Size Report
R. Henrique-Pinto, V.A. Janasi, C.C.G. Tassinari, B.B. Carvalho, C.R. Cioffi, N.M. .... Key words: Ribeira Fold Belt; São Roque Group; provenance; Sm-Nd isotope ...
Accepted Manuscript Provenance and sedimentary environments of the Proterozoic São Roque Group, SEBrazil: contributions from petrography, geochemistry and Sm-Nd isotopic systematics of metasedimentary rocks R. Henrique-Pinto, V.A. Janasi, C.C.G. Tassinari, B.B. Carvalho, C.R. Cioffi, N.M. Stríkis PII:

S0895-9811(15)30032-8

DOI:

10.1016/j.jsames.2015.07.015

Reference:

SAMES 1432

To appear in:

Journal of South American Earth Sciences

Received Date: 17 January 2015 Revised Date:

21 July 2015

Accepted Date: 22 July 2015

Please cite this article as: Henrique-Pinto, R., Janasi, V.A., Tassinari, C.C.G., Carvalho, B.B., Cioffi, C.R., Stríkis, N.M., Provenance and sedimentary environments of the Proterozoic São Roque Group, SE-Brazil: contributions from petrography, geochemistry and Sm-Nd isotopic systematics of metasedimentary rocks, Journal of South American Earth Sciences (2015), doi: 10.1016/ j.jsames.2015.07.015. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT 1

Provenance and sedimentary environments of the Proterozoic São Roque Group, SE-

2

Brazil: contributions from petrography, geochemistry and Sm-Nd isotopic

3

systematics of metasedimentary rocks

4 Henrique-Pinto, R.a; Janasi, V.A.a; Tassinari, C.C.G.a; Carvalho, B.B.b; Cioffi, C.R.a;

5

Stríkis, N.M.a a

7 8

b

Instituto de Geociências, Universidade de São Paulo, São Paulo, Brazil.

RI PT

6

Département des Sciences Appliquées, Université du Québec à Chicoutimi, Québec, Canada. *Corresponding author: [email protected]

9

11

SC

10

Abstract

12

The Proterozoic metasedimentary sequences exposed in the São Roque Domain (Apiaí

14

Terrane, Ribeira Belt, southeast Brazil) consist of metasandstones and meta-felspathic wackes with

15

some volcanic layers of within-plate geochemical signature (Boturuna Formation), a passive

16

margin turbidite sequence of metawackes and metamudstones (Piragibu Formation), and volcano-

17

sedimentary sequences with MORB-like basalts (Serra do Itaberaba Group; Pirapora do Bom Jesus

18

Formation). A combination of zircon provenance studies in metasandstones, whole-rock

19

geochemistry and Sm-Nd isotopic systematics in metamudstones was used to understand the

20

provenance and tectonic significance of these sequences, and their implications to the evolution of

21

the Precambrian crust in the region.

TE D

M AN U

13

Whole-rock geochemistry of metamudstones, dominantly from the Piragibu Formation,

23

points to largely granitic sources (as indicated for instance by LREE-rich moderately fractionated

24

REE patterns and subtle negative Eu anomalies) with some mafic contribution (responding for

25

higher contents of Fe2O3, MgO, V, and Cr) and were subject to moderate weathering (CIA - 51 to

26

85). Sm-Nd isotope data show three main peaks of Nd TDM ages at ca. 1.9, 2.1 and 2.4 Ga; the

27

younger ages define an upper limit for the deposition of the unit, and reflect greater contributions

28

from sources younger than the >2.1 Ga basement.

AC C

29

EP

22

The coincident age peaks of Nd TDM and U-Pb detrital zircons at 2.1-2.2 Ga and 2.4-2.5

30

Ga, combined with the possible presence of a small amount of zircons derived from mafic

31

(gabbroid) sources with the same ages, as indicated by a parallel LA-ICPMS U-Pb dating study in

32

metapsammites, are suggestive that these were major periods of crustal growth in the sources

33

involving not only crust recycling but also some juvenile addition.

34

A derivation from similar older Proterozoic sources deposited in a passive margin basin is

35

consistent with the main sedimentary sequences in the São Roque Domain being broadly coeval

ACCEPTED MANUSCRIPT 36

and in part laterally continuous. The coincident age, Sm-Nd isotope signature and geographic

37

proximity make the exposures of basement orthogneisses in the Apiaí Terrane candidates for

38

source material to the São Roque Domain. Additional sources with younger Nd TDM could be

39

juvenile 2.2 Ga basement from the southern portion of the São Francisco Craton and its marginal

40

belts (e.g., Mineiro Belt and Juiz de Fora Complex).

41 43

Key words: Ribeira Fold Belt; São Roque Group; provenance; Sm-Nd isotope signature; paleo-

RI PT

42

environmental reconstruction.

44 45

1. Introduction

Provenance studies of shales and mudstones are especially appealing, since they are

47

the most abundant sedimentary rocks in the geological record; however, they are

48

particularly difficult to study because the very small size of their components restricts the

49

use of standard petrographic tools. Thus, trace-element geochemistry, combined with

50

isotope data (Sm-Nd, but also Rb-Sr, Pb-Pb and Lu-Hf), has proven as an important

51

instrument to determine the relative contributions of felsic and mafic sources, as well as

52

the tectonic settings and secular trends in crustal evolution of these rocks (McLennan et al.,

53

1990; McLennan and Hemming, 1991; McLennan et al., 1995). Additionally, Th/Sc,

54

La/Sc, La/Lu ratios are higher in felsic rocks, while elements as Cr, Ni, Sc are more

55

concentrated in mafic igneous rocks (Cullers et al., 1987; Cullers and Berendsen, 1988;

56

Cullers and Podkovyrov, 2002). The size of the negative Eu anomalies in the source

57

appears to be preserved in fine-grained sediments, and thus can be used in studies of

58

provenance; for instance, mafic igneous rocks contribute slight positive or no Eu anomalies

59

(Eu/Eu*).

EP

TE D

M AN U

SC

46

Weathering of biotite, amphibole, pyroxene, olivine and opaque minerals produces

61

clay minerals such as smectite-vermiculite, whereas feldspars typically weather to kaolinite

62

and illite. The intensity of the weathering process can be measured by the ratio between the

63

“immobile” element Al and “mobile” elements such as Ca, Na and K. The effects of

64

chemical weathering can be measured by the Chemical Index of Alteration (CIA) (Nesbitt

65

and Young, 1982, 1984 and 1989; Nesbitt et al., 1996; Nesbitt and Markovics, 1997).

66

Taking into account these properties, many authors have attempted paleoenvironmental

67

reconstruction in geological sequences with ages ranging from Precambrian to Recent

68

(Nesbitt and Young, 1982; Sawyer, 1986; Harnois, 1988; McLennan et al., 1993; Fedo et

AC C

60

2

ACCEPTED MANUSCRIPT 69

al., 1995; Nesbitt et al., 1996; Cullers, 2000; Bauluz et al., 2000; Bahlburg and Dobrzinski,

70

2009).

71

This work presents the results of a provenance study of low- to medium-grade

72

metasedimentary rocks exposed in the São Roque Domain (SRD) in the Proterozoic

73

Ribeira Belt, SE Brazil. Our previous works (Henrique-Pinto and Janasi, 2010; Henrique-

74

Pinto

75

metaconglomerates and associated metarkoses from exposures of the lower stratigraphic

76

unit (Boturuna Formation) in a restricted area at the NW of the city of São Paulo. Here we

77

use petrography, geochemistry and Sm-Nd isotope geochemistry as main instruments to

78

extend that study to a broader area that encompasses a large portion of the SRD exposures,

79

including samples of meta-sandstones. Our results are integrated with those from a

80

provenance study based on detrital zircon chemistry and U-Pb dating (Henrique-Pinto,

81

2012; Henrique-Pinto et al., 2015).

82

2. Geological Setting

83

2.1. The Ribeira Belt

al.,

2012)

investigated

the

paleoenvironment

and

provenance

of

M AN U

SC

RI PT

et

The term “Ribeira Fold Belt” was originally defined to refer to the whole orogenic

85

system running parallel to the coastline of southeast and south Brazil (Hasui et al. 1975).

86

Current usage restricts the term to the central segment of this system, corresponding to a

87

~N60E trending, 100-200 km wide domain that was strongly affected by Neoproterozoic

88

(~800-500 Ma) deformation, metamorphism and granitic magmatism (e.g. Campanha and

89

Sadowski, 1999; Campos Neto, 2000; Heilbron et al., 2004 and 2008; Trouw et al., 2013).

90

Defined as such, it corresponds to a southern continuation of the Araçuaí Belt (developed

91

at the eastern margin of São Francisco craton), and is located to the north of the Luis Alves

92

“cratonic fragment” (Fig. 1).

EP

AC C

93

TE D

84

A southward change in structural trend and dominant tectonic flow (from orogen-

94

transverse to orogen-normal) in the transition from the Araçuaí to the Ribeira Belt is

95

related by some authors to contrasted responses of collision against a rigid lithospheric

96

block (the São Francisco Craton) versus a least stiff (and thinner) lithosphere (Vauchez et

97

al., 1994). Campanha and Brito Neves (2004) emphasizing the orogen-parallel tectonics

98

have interpreted the Ribeira Belt as the product of oblique collisional events. Alternative

99

models admit that the Ribeira orogen developed after the collage of the São Francisco

100

craton with another cratonic block now hidden beneath the Phanerozoic Paraná Basin; the

101

suture zone would correspond to a regional NNW-trending gravity limit (Mantovani and

3

ACCEPTED MANUSCRIPT 102

Brito Neves, 2005). In these models, components of the Ribeira Belt are interpreted as the

103

reworked borders of one or the other of these cratonic blocks (e.g., Campos Neto and

104

Caby, 2000; Trouw et al., 2013) A major source of uncertainty on the tectonic meaning of the Ribeira Belt within

106

the framework of the whole orogenic system is therefore the lack of obvious connections

107

with a stable cratonic area. This is aggravated by its involvement in a major dextral shear

108

zone that sliced the belt in elongated fault-bounded blocks in such a way that much of the

109

original information on vergence, lateral correlation and paleogeography of the

110

metasedimentary units may have been obscured (e.g., Campanha and Sadowski, 1999;

111

Campanha and Brito Neves, 2004; Heilbron et al., 2008).

SC

RI PT

105

Although there is some controversy in the literature about the number of blocks and

113

their limits, and even about the inclusion of some of them in the Ribeira Belt, we follow

114

subdivisions by Campos Neto (2000) and Heilbron et al. (2004, 2008), who distinguish

115

three major lithotectonic units in the Southern Ribeira Belt (Apiaí, Embu and Curitiba

116

Terranes), and another four in the Central Ribeira Belt (Occidental, Paraíba do Sul,

117

Oriental and Cabo Frio Terranes). In this conception, the northwest limit of the Southern

118

Ribeira Belt is defined by the Jundiuvira Shear Zone (Fig. 2A), which separates it (where

119

not covered by Phanerozoic sediments) from the Socorro-Guaxupé Nappe, a

120

Neoproterozoic high-grade Terrane accreted to the southern border of the São Francisco

121

Craton. Its southeast limit is defined by the Lancinha-Cubatão Shear Zone, which separates

122

it from the Oriental Terrane. In its southernmost portion, the Ribeira Belt is bound to the

123

south by Paleoproterozoic granulites unaffected by the Neoproterozoic thermal event and

124

thus described as a “cratonic fragment” (the Luiz Alves Microplate; Basei et al., 2009).

EP

TE D

M AN U

112

The Apiaí Terrane (Fig. 1), used here as geographic connotation, lies to the north

126

of the Curitiba Terrane, and is divided into the north-eastern São Roque Domain and the

127

south-western Açungui Domain.

128

AC C

125

The Açungui Domain comprises different metasedimentary successions of distinct

129

ages and lithological content. Some of the most expressive groups (Água Clara,

130

Votuverava and Perau) have Mesoproterozoic minimum ages, as indicated by the ~1.5-1.4

131

Ga U-Pb zircon ages of interlayered metabasic rocks (Basei et al., 2008; Campanha et al.,

132

2010; Siga Jr et al., 2011a). The Votuverava Group is admitted by some authors as a back-

133

arc sequence on the basis of the geochemical signature of the metabasic rocks (Faleiros et

134

al., 2011) while others interpret it as a passive margin sequence (Siga Jr et al., 2011a; Siga

135

Jr et al., 2011b). A Statherian (~1.75-1.8 Ga) rifting process is suggested by frequent 4

ACCEPTED MANUSCRIPT occurrences of deformed syenogranites and metabasic rocks of within-plate affinity

137

intruding Paleoproterozoic orthogneisses in small basement windows of the Votuverava

138

and Perau Groups (Cury et al., 2002; Siga Jr et al., 2007; Siga Jr et al., 2011b). No

139

Statherian metasedimentary sequences were recognized so far; however, as 1.5-1.4 Ga are

140

minimum depositional ages for both the Votuverava and Perau Groups, these successions

141

could potentially be connected to that rifting episode.

RI PT

136

A carbonatic open-sea shelf characterized by interlayered terrigenous and clast-

143

chemical sediments (Lajeado Group; Campanha and Sadowski, 1999) located to the north

144

of the Votuverava Group is interpreted as a passive-margin sequence that could correspond

145

to a more proximal sequence of the same basin. S-SE-directed paleocurrents (Campanha

146

and Sadowski, 1999) are consistent with this interpretation. The depositional age of the

147

Lajeado Group is constrained between 1.4 Ga and 0.88 Ga (Campanha et al., 2010).

SC

142

At least two volcano-sedimentary successions admitted as of Neoproterozoic age

149

occur in the Açungui Domain: the Itaiacoca carbonate platform sequence (minimum age

150

~1.0-0.9 Ga based on intrusive metabasic rocks) and Ediacaran volcanic-clastic sequences

151

filling small basins that are broadly contemporaneous with the granitic plutonism, either

152

“syn-orogenic” (Itaiacoca II sequence, ~0.65-0.63 Ga; Siga Junior et al., 2009), or “post-

153

orogenic” (the ~0.58 Ga Iporanga pull-apart basin; Campanha et al., 2008).

TE D

M AN U

148

The Embu Terrane, located between the Caucaia/Paraíba do Sul and

155

Lancinha/Cubatão Fault Systems (Fig. 1), is made up of low- to high grade

156

metasedimentary sequences with a few windows of Paleoproterozoic basement, the most

157

expressive of which corresponds to the Rio Capivari migmatites, dated at ~2.1 Ga and

158

showing Archaean (~2.9-2.7 Ga) crust residence, as evidenced by inherited zircon crystals

159

and Nd TDM model ages (Babinski et al., 2001). The metamorphic grade of the

160

metasedimentary sequences increases eastward, reaching high amphibolite to granulite

161

facies.

AC C

162

EP

154

The depositional age(s) of the Embu Terrane metavolcano-sedimentary sequence(s)

163

are poorly constrained; upper and lower limits are given respectively by the age of

164

metamorphism and intrusive orthogneisses at ~0.8 Ga (Vlach, 2001; Cordani et al., 2002)

165

and by Nd TDM model ages of metasedimentary rocks at ~1.8 Ga (Dantas et al., 2000).. An

166

constraint on the maximum depositional age was proposed by Trouw et al. (2013) from a

167

zircon provenance study of two quartzite samples (eastern portion), both showing identical

168

patterns with SRD (Henrique-Pinto et al., 2015), with strong peak at ca. 2.2 Ga and smaller

5

ACCEPTED MANUSCRIPT 169

peaks spreading to ages as old as 3.5 Ga; 0.8-0.6 Ga ages are associated with metamorphic

170

overgrowths.

171 172

2.2. The São Roque Domain The northernmost fault-bounded block of the Apiaí Terrane (Fig. 2A) is composed

174

of medium- to low-grade metavolcano-sedimentary Proterozoic sequences intruded by

175

large volumes of Ediacaran granites. The stratigraphy of the metavolcano-sedimentary

176

sequences, originally grouped into a single unit (São Roque Group) is currently subject of

177

some controversy (e.g. Juliani and Beljavskis, 1995; Henrique-Pinto and Janasi, 2014).

RI PT

173

A two-fold stratigraphic division was initially proposed by Hasui et al. (1976), who

179

distinguished in the western portion of the domain: the Boturuna (sericitic phyllites with

180

lens of quartzite at the bottom and carbonatic rocks at the top) and Piragibu (rhytmic

181

turbidites with alternating phyllites and quartzites) formations. A low-grade metavolcano-

182

sedimentary sequence locally underlies the Piragibu Formation in this region, and is

183

dominated by MORB-like tholeiitic metabasalts with pillow-lava structures (Figueiredo et

184

al., 1982; Tassinari et al., 2001) associated with pyroclastic rocks and meta-limestones

185

showing well-preserved stromatolite structures (1700 to 850 Ma; Bergmann and Fairchild,

186

1985). This sequence was named Pirapora do Bom Jesus Formation and interpreted as

187

passive margin volcanic centers forming atoll-like structures by Bergmann (1988). An

188

Ediacaran (628 ± 9 Ma) U-Pb monazite age from a metabasalt from the Pirapora sequence

189

led some authors (e.g., Hackspacher et al., 2000; Juliani et al. 2000) to interpret it as part of

190

a Neoproterozoic back-arc basin. Tassinari et al. (2001) interpreted the Pirapora sequence

191

as an ophiolite slice, in view of the important volume of mafic magmatic rocks with pillow

192

lavas, MORB-type chemistry and association with magnetite/chromite-talc schists. An

193

Ediacaran depositional age seems unlikely for the Pirapora sequence in view of its

194

stratigraphic position and dating of the other sequences as described below.

M AN U

TE D

EP

AC C

195

SC

178

The eastern continuation of the basal Boturuna Formation is characterized by the

196

predominance of meta-feldspathic wackes interlayered with polymictic metaconglomerates

197

(which have pebbles and cobbles encased in a metarkose framework and local meta-

198

quartzarenites), local meta-quartzarenites (Pico do Jaraguá) and small bodies of

199

metavolcanic rocks (basaltic trachyandesites and porphyritic meta-trachydacites; Carneiro,

200

1983; Carneiro et al., 1984; Henrique-Pinto and Janasi, 2010). The volcanism is bimodal

201

and has a within-plate geochemical signature (low mg#, high Zr, Y, Nb, and low Sr;

6

ACCEPTED MANUSCRIPT 202

Henrique-Pinto and Janasi, 2010). A ~1.75-1.80 Ga depositional age seems well

203

established from U-Pb zircon dating of these meta-trachydacites (1790 ± 14 Ma; van

204

Schums et al., 1986) and metabasic rocks (1750 ± 40 Ma metamicrogabbro with relics of

205

clinopyroxene and preserving an intergranular texture; Oliveira et al., 2008). In the eastern portion of the São Roque Domain, Coutinho et al. (1982) recognized

207

a distinctive metavolcano-sedimentary sequence (basic volcanics, sub-volcanics and tuffs

208

interlayered with pelites, marls and chemical sediments) and an upper metasedimentary

209

sequence (clay-silt rhytmites and carbonatic sediments). Initially correlated to the Boturuna

210

Formation, the lower metavolcano-sedimentary sequence was renamed the Serra do

211

Itaberaba Group by Juliani et al. (1986), on the basis of its higher metamorphic grade

212

(amphibolite-facies) and the proposed existence of an erosive contact marked by the

213

presence of clasts and volcanic fragments derived from it, in metaconglomerates from the

214

Boturuna Formation. However, a meta-andesite unit, interpreted as a small intrusion

215

related to the beginning of sedimentation in the Serra do Itaberaba Group and located

216

stratigraphically above a MORB-like metamafic unit containing amphibolites and

217

metatuffs, yielded a U-Pb zircon age of 1395 ± 10 Ma, which would provide the minimum

218

age of deposition (Juliani et al., 2000). Considering the above constraints for the São

219

Roque Group, this age suggests that the Serra do Itaberaba Group could be younger than

220

the Boturuna Formation.

TE D

M AN U

SC

RI PT

206

The uppermost unit in the São Roque Group is the Piragibu Formation, a rhythmic

222

sequence with a predominance of meta-mudstones interbedded with metawackes, which

223

may correspond to turbidity current deposits in a marine environment (e.g., Juliani and

224

Beljaviskis, 1995, and references therein). In summary, lithostratigraphic and

225

geochronological information suggests that up to three main (metavolcano)-sedimentary

226

sequences are present in the São Roque Domain: (1) a lower Statherian (~1.75 Ga) rift

227

sequence (Boturuna Formation); (2) an intermediate Calymmian (~1.4 Ga?) metavolcano-

228

sedimentary sequence with MORB-like magmatism and variously interpreted as back-arc

229

or passive margin (the Serra do Itaberaba Group and possibly the lower-grade Pirapora do

230

Bom Jesus Formation); and (3) an upper unit of platform turbidites (the Piragibu

231

Formation).

AC C

EP

221

232

7

ACCEPTED MANUSCRIPT 233

3. Sampling and analytical procedures The rock samples chosen for this study were collected to assemble a representative

235

set of the São Roque metasedimentary succession in terms of grain size and mineralogical

236

and textural maturity, and targeting the best available exposures, in order to avoid, as far as

237

possible, the effects of weathering, which are widespread in the region. A total of 30

238

samples were selected for whole-rock geochemistry. Four of these samples were collected

239

from units very similar to Piragibu and Boturuna Formations, but outcropping just north of

240

the Jundiuvira Shear Zone and therefore outside the São Roque Domain. The chemical

241

analyses were preceded by petrographic studies and modal counting, for which 500 points

242

were counted per thin section (Table 1).

SC

243

3.1. Whole-rock chemistry

M AN U

244

RI PT

234

245

Chemical analyses were carried out at the Geoanalitica Core Research Center,

246

Instituto de Geociências, Universidade de São Paulo, Brazil. Samples were crushed in a

247

steel jaw-crusher and subsequently in an agate disk mill. Whole-rock major and trace

248

element compositions were obtained by XRF spectrometry, respectively from pressed

249

pellets and fused discs, following the analytical protocol described in Mori et al. (1999). Rare earth elements (REE) and other trace-elements present in low contents

251

(typically < 100 ppm) were measured by inductively coupled plasma mass spectroscopy

252

(ICP-MS) in a Perkin Elmer Plasma Quadrupole MS ELAN 6100DRC, following the

253

analytical protocols described in Navarro et al. (2002). Aliquots of 100 mg powder were

254

mixed with 5 ml HNO3 and 15 ml HF in Parr type bombs and then heated at ~200° C for

255

five days, to ensure complete dissolution of ultra-stable minerals such as zircon.

257 258

EP

AC C

256

TE D

250

3.2. Sm-Nd analyses

Whole-rock Sm-Nd isotope analyses (n=20) were performed on the same powders

259

used for elemental geochemistry at the Centro de Pesquisas Geocronológicas (CPGeo),

260

Instituto de Geociências, Universidade de São Paulo, Brazil. Samples were dissolved by

261

acid attack (5 ml HNO3 and 15 ml HF) in Parr-type bombs at T~160° C for ten days. For

262

isotope separation, conventional cation exchange columns filled with resin AG 50 (200-

263

400 mesh) using HCl and water in varying concentration were employed.

264

The Nd isotopic ratios were obtained using a Finnigan MAT-262 multi-collector

265

mass spectrometer, whereas the Sm isotopic ratios were obtained in a VG-354 single

8

ACCEPTED MANUSCRIPT 266

collector mass spectrometer. The average 143Nd/144Nd values measured for the La Jolla and

267

BCR-1 Nd standards during the period of this study were 0.511849 ± 0.000025 and

268

0.512662 ± 0.000027, respectively. The maximum measured errors were 0.09% for the

269

147

270

assume present CHUR ratios of

271

decay constant used was 6.54 x 10-12 years-1. Nd TDM ages were calculated according to

272

DePaolo (1988). Details of the analytical protocol are given in Sato et al. (1995).

Sm/144Nd ratio and ± 0.00002 for

Nd/144Nd (2σ precision level). εNd calculations

Nd/144Nd= 0.512638 and

273 274

147

Sm/144Nd= 0.1967. The

RI PT

143

143

4. Petrography

Using the compositional maturity, based on the proportion of quartz, feldspar

276

and lithic fragments, and the textural maturity, based on the proportion between framework

277

and matrix (McBride, 1963; Dott, 1964), modal counting for some the studied samples

278

allowed the classification of the metasedimentary rocks into six subtypes (Fig. 3).

M AN U

SC

275

The samples with greater sedimentary maturity (< 10% matrix and > 75% quartz)

280

are classified as meta-quartzarenites and meta-subarkoses (inset X in Fig. 3). In some cases

281

these rocks lost the original sedimentary petrofabrics due to metamorphic overprint,

282

reflecting the low competence of quartz during deformation and increase of temperature

283

(Figs. 4A and B).

TE D

279

The lowest compositional maturity (>25% feldspar content) and sedimentary

285

petrofabrics (angular feldspar crystals) of metarkoses (Fig. 4C) and meta-feldspathic

286

wackes (Fig. 4D) suggest short transport distances. The similar proportions of plagioclase

287

and alkali-feldspar indicate that their main sources were of granitic composition.

288

Additional sources are preserved as lithic fragments of metabasic rocks and quartzarenites,

289

both always present in small modal proportions (less than 1%).

AC C

290

EP

284

The metamudstones and meta-quartz wackes (Figs. 4E an F) are characterized by

291

low textural and high compositional maturities (respectively more than 40% matrix and

292

over 70% quartz, inset Y in Fig. 3). These rocks are mostly composed of very fine to fine-

293

grained particles, with sub-angular to rounded grains, and their original sedimentary

294

structures are often preserved, e.g., as plane-parallel layering with clay-rich and quartz-rich

295

bands in metamudstones (Fig. 4F).

296

9

ACCEPTED MANUSCRIPT 297

5. Geochemistry Chemical classification based on major elements shows a good correlation with the

299

petrographic classification, except for meta-feldspathic wackes containing less than 40%

300

matrix, which are chemically indistinguishable from metarkoses, despite their different

301

proportions of matrix (Fig. 5). Given the post-depositional processes that affected these

302

rocks during diagenesis and metamorphism, it is necessary to take into account that some

303

uncertainty is associated with the estimative of the matrix proportion (more than 10% -

304

wackes), due to the potential generation of pseudo-matrix.

306

5.1. Potential source-areas and weathering

SC

305

RI PT

298

The granitic clasts of polymictic metaconglomerates from the Boturuna Formation,

308

which correspond to a broadly comagmatic suite of Paleoproterozoic (~2.2 Ga) age

309

(Henrique-Pinto and Janasi, 2010; Henrique-Pinto, 2012), bear important direct evidence

310

on the nature of the source areas of basal Formations of the São Roque Group. Pebbles of

311

other rock types (although much less abundant), include amphibolite and quartzite of

312

mature polycyclic quartzose detritus, revealing contributions from different sources.

M AN U

307

In order to infer processes affecting the sources of the studied metasedimentary

314

rocks, we used some of the indices that allow to evaluate the effects of processes as

315

weathering and metasomatism such as CIW (Chemical Index of Weathering; Harnois,

316

1988), CIA (Chemical Index of Alteration; Nesbitt and Young, 1982), PIA (Plagioclase

317

Index of Alteration; Fedo et al., 1995) and ICV (Index of Compositional Variability; Cox

318

et al., 1995) (Fig. 6). A few of our samples were not used in this evaluation: samples JP-20,

319

PJ-01 and JP-01 (Table 2) with high K2O contents, possibly due to late diagenetic and/or

320

metamorphic processes, and samples JP-04, MD-03a and MD-38, with secondary calcite

321

(the parameters used to quantify the weathering require that the sources of CaO are

322

exclusively silicate minerals).

EP

AC C

323

TE D

313

The CIW indicates that the particles derived or weathered from the source suffered

324

sedimentary sorting (Fig. 6A) and were deposited as sands and clays after moderate

325

degrees of weathering with CIA values between 51 and 85, while the ICV, used to evaluate

326

the original composition of the sources of shales and siltstones (Fig. 6B), illustrates the

327

chemical effects of weathering of the potential source. These values would correspond to

328

transformation of feldspar to illite, indicating that the highest degree of weathering with

329

kaolinite formation was not attained (Fig. 7).

10

ACCEPTED MANUSCRIPT The CIW values for most of the feldspatic wackes from the Boturuna Formation

331

(samples MD-03a, MD-04a, MD-26b, MD-36 and MD-01b) are similar to the granitic

332

clasts from the associated metaconglomerates (averages respectively 67 and 63), indicating

333

weak weathering (cf. Henrique-Pinto and Janasi, 2010). The PIA index excludes the

334

influence of K, which is much less mobile than Ca and Na, and shows a slightly larger

335

difference (averages respectively 57 and 49). The CIW and PIA of the Piragibu

336

metamudstones and of the other metapsmmites (metarenites, subarkoses, etc) are close to

337

100, reflecting near complete removal of Ca and Na from the sources.

339

5.2. Inferences on source areas from geochemistry

SC

338

RI PT

330

The strong linear correlation of SiO2 with the main oxides Al2O3 (r= -0.99), Fe2O3

341

(r= -0.86), K2O (r= -0.92), TiO2 (r= -0.95) (Supplementary I, Fig. 8) is mainly related to

342

sedimentary sorting responsible for the concentration of these elements in the Al-rich clay

343

fraction. The largest scattering of MgO with small negative linear correlation relative to

344

SiO2 (r= -0.38) could reflect the presence of microlithic fragments of metabasic rocks,

345

found in small proportions in some metawacke samples; this could also be responsible for

346

the increase of CaO (up to 0.05 wt%). These increases might also in part reflect the

347

presence of dolomite/calcite as authigenic cement (not identified in thin section) or derived

348

from secondary hydrothermal processes.

TE D

M AN U

340

Many trace elements such as Cr (r= 0.87), Rb (r= 0.91), Ba (r= 0.82), V (r= 0.90),

350

Sc (r= 0.93) and Ga (r= 0.95) show very strong to strong positive correlation with Al2O3

351

(Supplementary I, Fig. 9), which reflects the preference of these elements for the clay

352

fraction in Al-rich sediments, and their depletion in quartz-rich fractions. The increasing

353

amounts of feldspar in the compositionally immature deposits (e.g., meta-feldspathic

354

wackes and metarkoses) could be responsible for the shifting of Sr, and the low contents of

355

V and Rb, compared to metamudstones and metaquartzarenites.

AC C

356

EP

349

The presence of metamafic clasts in metaconglomerates from the Boturuna

357

Formation (Henrique-Pinto and Janasi, 2010) is a clear physical evidence of the

358

contribution from basic sources. These clasts have trace element ratios typical of basic

359

magmatic rocks (e.g., Sc/Th Sc/La, Cr/, Cr/Sc, U/Th and Co/Th - Fig. 10B). Furthermore,

360

elements that are abundant in basic magmatic rocks and tend to accumulate in clay-rich

361

sediments (e.g., Ti, Ni, Cr, Co, Sc and V) are typically enriched in mudstones (e.g.,

362

Sawyer, 1986), compared with high-textural maturity rocks (Figs. 8 and 9).

11

ACCEPTED MANUSCRIPT 363

Compared with the compositions of sediments derived from different magmatic

364

sources presented by Cullers (2000), key trace-element ratios of our samples are clearly

365

within the range of siliciclastic sources [e.g., high La/Sc (1.9 to 26), Th/Sc (0.6 to 2.9),

366

La/Co (7.7 to 102), Th/Co (0.4 to 4.7) and Th/Cr (0.09 to 0.6) ratios]. Metamudstones from the Piragibu Formation are enriched in REE (Fig. 10 A; Table

368

3) and display more fractionated REE patterns (LaN/YbN= 15-40; GdN/YbN= 2.2-3.0;

369

∑HREE= 10-64 ppm) when

370

metasedimentary rocks from the Boturuna Formation. Well-defined negative Ce (Ce/Ce*=

371

0.34-0.51) and Eu (Eu/Eu*= 0.64-0.71) anomalies are common in the metamudstones, with

372

the exception of one sample (ND-08, which has no Ce anomaly and is less fractioned, as a

373

result of lower LREE contents).

to other (coarser-grained) siliciclastic

SC

compared

RI PT

367

The compositional more immature metasedimentary rocks (metarkoses and meta-

375

feldspathic wackes, Fig. 3) show REE behaviour broadly similar to the granitic clasts from

376

the metaconglomerates, with moderately fractionated REE patterns (LaN/YbN= 10-13),

377

high LREE contents (∑LREE= 111-183 ppm), and incipient negative Eu anomalies

378

(Eu/Eu*= 0.69-0.96). An Eu increase in some cases results in positive anomalies (Eu/Eu*=

379

1.08; sample JP-01), which may reflect feldspar concentration as a result of sedimentary

380

sorting (cf. Singh and Rajamani, 2001) or alternatively result from contributions of Eu-rich

381

sources (e.g., igneous rocks of intermediate composition with Eu/Eu* = 0.72-1.03; Fig.

382

10A).

TE D

M AN U

374

The nearest potential source areas with similar ages are found in basement nuclei of

384

the Açungui Domain (Kaulfuss, 2001; Ribeiro, 2006; Siga Jr. et al., 2007, 2011a). The

385

chemical composition of these rocks is similar to the granitic clasts of metaconglomerates

386

(Boturuna Formation) at a given silica content (65-78 wt.%) (Group 1 in Figs. 8 and 9).

387

Intermediate plutonic rocks (Group 2 in Figs. 8 and 9) are common in these basement

388

nuclei but have not been found as clasts in the metaconglomerates studied by Henrique-

389

Pinto and Janasi (2010). Small contributions from additional sources as well as igneous

390

rocks of intermediate composition (e.g., andesitic) are suggested by the presence of TiO2-

391

Ba-V-rich mudstones, which could not be explained only by mafic sources or simple

392

sedimentary sorting effect.

AC C

EP

383

393

The quartz-rich metasandstones are REE-poor (∑REE= 59-65 ppm) and have

394

relatively high LaN/SmN ratios (3.9-5.7), weakly fractionated patterns (LaN/YbN= 6-8), with

395

the exception of sample JP-19, which is depleted in HREE, resulting in a more fractionated

396

pattern with LaN/YbN= 21 (Fig. 10A). Strong positive linear correlations between ∑HREE 12

ACCEPTED MANUSCRIPT 397

and ∑LREE with Th (r= 0.86 and 0.85, respectively; Supplementary I) and between Y and

398

REE suggest an important control by heavy minerals such as monazite and xenotime. Ce-depleted REE patterns such as those shown by some metamudstone samples

400

(Fig. 11B) are commonly observed in seawater sediments (e.g., Shimizu and Masuda,

401

1977; Elderfield and Greaves, 1982). Furthermore, HREE-depleted metawackes and

402

metamudstones (Figs. 11 A and C) with positive Eu anomalies relative to post-Archean

403

Australian shales (Figs.11 C and D) could be an indication that additional volcanogenic

404

sources were present during sedimentation, which is also suggested by less negative ƐNd(t)

405

of two metamudstone samples.

RI PT

399

All samples have chemical compositions consistent with those expected from

407

sediments deposited in a passive margin basin, as shown by their REE patterns and by their

408

position in discrimination diagrams that identify the provenance signature (Fig. 12). This is

409

confirmed by the Sm-Nd isotope data that suggest predominantly older felsic Proterozoic

410

sources, with subordinate contributions from mafic crust (Figs. 13A and B).

M AN U

SC

406

411 412

6. Sm-Nd isotope data from metamudstones

Previously available Sm-Nd isotope data for the São Roque Group rocks are

414

restricted to results presented by Dantas et al. (2000) for some metapelites and a single

415

amphibolite, which yielded Paleoproterozoic to Archaean (1.86-2.86 Ga) Nd TDM model

416

ages, and to a systematic study of ~2.2 Ga old granitic clasts and the framework of a

417

metaconglomerate from the Boturuna Formation (Henrique-Pinto et al., 2012) whose Nd

418

TDM model ages cluster at 2.6- 2.8 Ga.

EP

TE D

413

Our Sm-Nd isotope data (Table 4) were obtained in 17 representative samples of

420

metamudstones of the São Roque Group, most from the Piragibu Formation. The results

421

span approximately the same range of Nd TDM indicated by previous works (1.9-3.0 Ga),

422

but show a well-defined clustering in the 2.1-2.6 Ga interval, where two peaks can be

423

identified at ~2.2 and 2.4-2.5 Ga. Another small peak is defined at ~1.9 Ga by four samples

424

(Fig. 14B); older (>2.9 Ga) Nd TDM is associated with a few samples with

425

0.13 and is possibly slightly exaggerated by REE fractionation.

AC C

419

147

Sm/144Nd>

426

The Sm-Nd isotope signatures of the metaconglomerate clasts from the Boturuna

427

Formation (Henrique-Pinto et al., 2012) and from the basement nuclei from the Açungui

428

Domain (Kaulfuss, 2001; Siga Jr. et al., 2011a) were used to calculate their ƐNd at the age

429

inferred for the deposition of the basal metasedimentary rocks of the SRS (~1.75 Ga). The

13

ACCEPTED MANUSCRIPT 430

ƐNd(1.75) values of the clasts (-7 to -10) and basement nuclei (-7 to -13) are more negative

431

compared to all metamudstones (+2 to -7), with the exception of sample ND-08 which has

432

ƐNd(1.75) = -9. The meta-feldspathic wacke from the Boturuna Formation has ƐNd(1.75)= -7, closer

434

to the values shown by the clasts, in agreement with its direct association with the

435

metaconglomerates (Fig. 14A). The least negative values of the metamudstones indicate

436

that other sources, younger and/or with less negative ƐNd at the age of deposition, also

437

contributed to the SRS metamudstones.

RI PT

433

A few samples with slightly positive ƐNd(1.75) (+1.4 to +2.4) were identified among

439

the metamudstones (Fig. 14A). These are located either to the north of the Jundiuvira Fault

440

(therefore outside the São Roque Domain, but corresponding to low-grade metamorphic

441

rocks not consistent with the metamorphic grade typical of the Socorro-Guaxupé Nappe),

442

or in the northeasternmost portion of the studied sector of the SRD (Fig. 1). Their positive

443

ƐNd(1.75)

444

contribution from younger sources, possibly including rocks such as the metabasalts dated

445

by Oliveira et al. (2008) at ~1.75 Ga, which have positive ƐNd(1.75).

M AN U

SC

438

and corresponding youngest Nd TDM ages (1.88-1.93 Ga) must reflect a

The study of detrital zircons from metapsammitic rocks yields some important

447

clues to the identification of the sources of the São Roque Domain (Henrique-Pinto et al.,

448

2015). Granitic sources seem to be largely predominant for these sediments, which show

449

main peaks of zircon U-Pb ages in the same range as the Nd TDM, in some cases with a

450

bimodal distribution (2.2 and 2.4 Ga) (Fig. 14C). One explanation for this coincidence

451

could be the existence of sources with juvenile signature at this age range, therefore with

452

less negative ƐNd(1.75) than the metaconglomerate clasts studied by Henrique-Pinto et al.

453

(2012). To our knowledge, such rocks have not yet been documented in the literature so far

454

in the small paleoproterozoic basement nuclei described in the Apiaí Terrane (e.g., the

455

Tigre, Setuva and Betara nuclei in Açungui Domain). We note, however, that recent

456

studies have identified rocks with these characteristics in other parts of southeast Brazil,

457

such as the orthogneisses found as allocthonous basement fragments in the Andrelândia

458

Nappe System (Campos Neto et al., 2011) or the Serrinha Arc, part of the Mineiro Belt in

459

the southeastern tip of the São Francisco Craton (Teixeira et al., 1996; Ávila et al., 2010).

AC C

EP

TE D

446

460

14

ACCEPTED MANUSCRIPT 461

7. Discussion The classification based on modal allowed the division of clastic lithotypes from

463

the São Roque Domain into six subtypes. Samples with greater sedimentary maturity were

464

classified as meta-quartzarenites and meta-subarkoses; samples with lowest compositional

465

maturity as metarkoses and meta-feldspathic wackes; and those with low textural maturity

466

but high compositional maturity as metamudstones and meta-quartz wackes.

RI PT

462

The presence of plagioclase and alkali-feldspar in similar proportions in metarkoses

468

and meta-feldspathic wackes from the Boturuna Formation (in the Morro Doce region)

469

indicates that the main sources of these rocks are of granitic composition, and the

470

preservation of sedimentary petrofabrics with sub-euhedral feldspar in the framework

471

suggests that they are proximal, i.e., implies short transport distances. Additional sources

472

are indicated by the presence of lithic fragments of metabasic rocks and intraclasts of

473

quartzarenite, but these are always of minor modal proportions (less than 1%).

M AN U

SC

467

The chemical classification using major elements shows great parallelism with the

475

modal classification, except for the metarkoses and meta-feldspathic wackes, which have

476

similar chemical behaviour notwithstanding their different proportions of matrix. The very

477

strong to strong negative linear correlation of SiO2 with the main major (Al2O3, Fe2O3,

478

K2O, TiO2) and trace elements (Cr, Rb, Ba, V, Ga) is attributed to sedimentary sorting and

479

concentration of these elements in the clay fraction in Al-rich sediments, which are

480

depleted in quartz.

TE D

474

Evidence of the basic sources are suggested by the increase of Fe2O3, MnO, MgO

482

and high ratios of Sc/Th, Sc/La, Cr/Sc, U/Th and Co/Th. Furthermore, the accumulation of

483

elements derived from basic rocks into clay-rich sediments is reflected in Ti, Ni, Cr, Co, Sc

484

and V enrichments in mudstones, compared with the high-textural maturity rocks. The SRD metasediments are inferred to have been deposited in a passive margin

AC C

485

EP

481

486

environment having older Proterozoic to Archean basement sequences as main sources, as

487

indicated by the geochemical signatures of both the proximal deposits of the Boturuna Fm.

488

and the distal deposits of the Piragibu Fm, suggesting that the deposition of these two units

489

may have been at least in part contemporaneous.

490

The Nd TDM ages of the SRD metamudstones (1.9-2.5 Ga) are characteristically

491

slightly younger than those of the granite clasts that are an important source of the

492

metaconglomerates and associated metarkoses of the Boturuna Fm. and correspond to 2.2

493

Ga products of reworking of older Archean (2.7 Ga) crust (Henrique-Pinto et al., 2012).

494

Exposures of basement rocks are unknown in the SRD, but are found in basement nuclei in

15

ACCEPTED MANUSCRIPT the Açungui Domain (orthogneisses from the Tigre, Setuva and Betara nuclei; Siga Jr et

496

al., 2007). These rocks have similar Paleoproterozoic (2.2 Ga) ages and Archean Nd TDM,

497

but are compositionally different from the São Roque metaconglomerate clasts (which are

498

typically more leucocratic). Migmatites from a basement exposure in the Embu Terrane

499

(Rio Capivari Complex) are also ~2.1 Ga old and have Archean (2.9-3.2 Ga) Nd TDM

500

(Babinski et al., 2001). These data imply that the compositions of typical SRD

501

metamudstones require involvement of additional sources to explain their lower Nd TDM

502

relative to the basement granite clasts and basement exposures in the Ribeira Belt.

RI PT

495

A potential way to lower the εNd(t) and consequently the Nd TDM of the

504

metamudstones would be the contribution from mantle-derived basic volcanic rocks

505

broadly coeval with deposition. Indeed, basic volcanic rocks are inferred from whole-rock

506

geochemistry as a contributing source to the SRD metamudstones, and possibly also to the

507

meta-sandstones (from the trace-element geochemistry of detrital zircons; Henrique-Pinto

508

et al., 2015). We consider it improbable, however, that such contribution is strong enough

509

to explain the observed shift in Nd TDM, given the rarity of mafic-derived detrital zircons in

510

the meta-sandstones and the low (0.09-0.13)

511

(since higher Sm/Nd ratios are more characteristic of basic rocks).

M AN U

SC

503

147

Sm/144Nd ratios of the metamudstones

U-Pb dating and geochemistry of detrital zircons from SRD metasandstones

513

indicated that their sources are similar to those of the marginal belts of the São Francisco

514

Craton, and therefore the São Francisco Paleoplate might extend southwestward and

515

constitute the basement of the Ribeira Belt (Henrique-Pinto et al., 2015). The Sm-Nd

516

isotope signature of the oldest (pre-1.4 Ga) passive-margin sequences of the Andrelândia

517

Group (e.g., Campestre Formation; Westin and Campos Neto, 2013) is indeed very similar

518

to that of the SRD metasediments, suggesting that they might be correlative. In this

519

context, it is possible that at least part of the lowering in the Nd TDM of the SRD

520

metamudstones could reflect contributions from ~2.2 Ga juvenile arc terranes such as those

521

exposed in the southern portion of the São Francisco Craton (e.g., the Mineiro Belt; Ávila

522

et al., 2010, 2014; Teixeira et al., 2015) which may continue southwestward as part of the

523

basement of the Andrelândia Group (cf. Fetter et al., 2001; Campos Neto et al., 2011).

524

8. Conclusions

AC C

EP

TE D

512

525

Petrography, geochemistry and Sm-Nd isotopic systematics of metasedimentary

526

rocks were used as provenance tools to estimate the sedimentary environments of the

16

ACCEPTED MANUSCRIPT 527

Proterozoic São Roque Domain. The main conclusions that can be addressed from our

528

study are:

529

(i) The sedimentary particles were subject to moderate degrees of weathering as indicated

531

by CIA values between 51 and 85. These values correspond to transformation of feldspar

532

to illite, indicating that the highest degree of weathering with kaolinite formation was not

533

attained.

RI PT

530

534

(ii) Strong negative linear correlation of SiO2 with the main major (Al2O3, Fe2O3, K2O,

536

TiO2) and trace elements (Cr, Rb, Ba, V, Ga) is attributed to sedimentary sorting and

537

concentration of these elements in the clay fraction. Evidences of basic magmatic sources

538

in some samples are the increase of Fe2O3, MnO, MgO and higher ratios of Sc/Th, Sc/La,

539

Cr/Sc, U/Th and Co/Th.

M AN U

540

SC

535

(iii) The sediments are inferred to have been deposited in a passive margin environment

542

having older Proterozoic to Archean basement sequences as main sources. The Nd TDM

543

ages (1.9-2.5 Ga) are slightly younger than those of the granite clasts of the Boturuna Fm.,

544

which correspond to 2.2 Ga products of reworking of older Archean (2.7 Ga) crust.

545

TE D

541

(iv) Similar petrography, geochemistry and isotope characteristics among metasedimentary

547

rocks in both sides of Jundiuvira Shear Zone suggest that the first-order limits and

548

discontinuities traditionally established for the Ribeira Belt are not defined by the strike-

549

slip fault systems to separate distinct domains (Socorro-Guaxupé and Apiaí).

550

EP

546

(v) Geochemistry, U-Pb zircon dating and Sm-Nd isotopes similarities with SRD, are

552

found in southeast part of basement nuclei in the Apiaí Domain (Tigre, Setuva and Betara

553

nuclei) and lowering in the Nd TDM could reflect contributions from ~2.2 Ga juvenile arc

554

terranes such as those exposed in the southern portion of the São Francisco Craton (e.g.,

555

the Mineiro Belt) which may continue southwestward as part of the basement of the

556

Andrelândia and Itapira Groups.

AC C

551

557

17

ACCEPTED MANUSCRIPT 558

8. Acknowledgements The authors acknowledge financial support by CNPq (Proc. 143521/2008-0) and

560

Fapesp (Proc. 2012/04148-0). Comments by Edward W. Sawyer and Antonio Carlos B.C.

561

Vasconcellos in preliminary version of this manuscript are much appreciated. Careful

562

reviews and suggestions by two anonymous reviewers and by Reinhardt A. Fuck helped

563

improve the final version.

RI PT

559

564

9. References

566

Ávila, C.A., Teixeira, W., Cordani, U.G., Moura, C.A.V., Pereira, R.M., 2010. Rhyacian (2.23-2.20

567

Ga) juvenile accretion in the southern São Francisco craton, Brazil: Geochemical and

568

isotopic evidence from the Serrinha magmatic suíte, Mineiro belt. Journal of South

569

American Earth Sciences, 29, 464-482.

SC

565

Ávila, C.A., Teixeira, W., Bongiolo, E.M., Dussin, I.A., Vieira, T.A.T., 2014. Rhyacian evolution of

571

subvolcanic and metasedimentary rocks of the southern segment of the Mineiro belt, Sao

572

Francisco Craton, Brazil. Precambrian Research, 243, 221-251.

M AN U

570

Babinski, M., Tassinari, C.C.G., Nutman, A.P., Sato, K., Iyer, S.S., 2001. U/Pb SHRIMP zircon

574

ages of migmatites from the basement of the Embu Complex, Ribeira fold belt, Brazil:

575

Indications for ~1.4-1.3 Ga Pb-Pb and Rb-Sr" isochron" ages of no geological meaning, III

576

South American Simposium on Isotope Geology. Extended Abstracts, Pucón, Chile, 91-

577

93.

TE D

573

Basei, M.A.S., Frimmel, H.E., Nutman, A.P., Preciozzi, F., 2008. West Gondwana amalgamation

579

based on detrital zircon ages from Neoproterozoic Ribeira and Dom Feliciano belts of

580

South America and comparison with coeval sequences from SW Africa. Geological

581

Society of London, Special Publications, 294(1), 239-256.

EP

578

Basei, M.A.S., Nutman, A.P., Siga Jr, O., Passarelli, C.R., Drukas, C.O., 2009. The evolution and

583

tectonic setting of the Luiz Alves Microplate of southeastern Brazil: an exotic terrane

584 585 586

AC C

582

during the assembly of Western Gondwana. In: C. Gaucher, A.N. Sial and H.E. Frimmel

(Editors), Neoproterozoic-Cambrian Tectonics, Global Change and Evolution: a focus on southwestern Gondwana. Developments in Precambrian Geology. Elsevier, 273-291.

587

Bahlburg, H., Dobrzinski, N., 2009. A review of the Chemical Index of Alteration (CIA) and its

588

application to the study of Neoproterozoic glacial deposits and climate transitions. The

589

Geological Record of Neoproterozoic Glaciations. Geological Society, London, 1-31.

590

Bauluz, B., Mayayo, M.J., Fernandez-Nieto, C., Lopez, J.M.G., 2000. Geochemistry of Precambrian

591

and Paleozoic siliciclastic rocks from the Iberian Range (NE Spain): implications for

592

source-area weathering, sorting, provenance, and tectonic setting. Chemical Geology, 168,

593

135-150. 18

ACCEPTED MANUSCRIPT 594

Bergmann, M., 1988. Caracterização Estratigráfica e Estrutural da Seqüência Vulcano-Sedimentar

595

do Grupo São Roque na Região de Pirapora do Bom Jesus - Estado de São Paulo. Master

596

thesis – Instituto de Geociências USP.

597

Bergmann, M., Fairchild, T.R., 1985. Estromatólitos do Grupo São Roque. Proterozóico Superior.

598

Região de Pirapora de Bom Jesus. Estado de São Paulo. Anais da Academia Brasileira de

599

Ciências, 57(1), 116-117. Bizzi, L.A., 2003. Geologia, tectônica e recursos minerais do Brasil: texto, mapas & SIG. Serviço

601

Geológico do Brasil, CPRM, Ministério de Minas e Energia, Secretaria de Minas e

602

Metalurgia.

604 605 606

Campanha, G.A.C., Brito Neves, B.B., 2004. Frontal and oblique tectonics in the Brazilian Shield. Episodes, 27(4), 255-259.

SC

603

RI PT

600

Campanha, G.A.C., Sadowski, G.R., 1999. Tectonics of the southern portion of the Ribeira Belt (Apiaí Domain). Precambrian Research, 98(1-2), 31-51.

Campanha, G.A.C., Basei, M.S., Tassinari, C.C.G., Nutman, A.P., Faleiros, F.M., 2008.

608

Constraining the age of the Iporanga Formation with SHRIMP U-Pb zircon: Implications

609

for possible Ediacaran glaciation in the Ribeira Belt, SE Brazil. Gondwana Research,

610

13(1), 117-125.

M AN U

607

Campanha, G.A.C., Basei, M.A.S., Faleiros, F.M., Tassinari, C.C.G., Nutman, A., Vasconcelos, P.,

612

2010. Geocronologia da porção meridional da Faixa Ribeira no sul do Estado de São

613

Paulo, 45 Congresso Brasileiro de Geologia. Sociedade Brasileira de Geologia, Belém,

614

PA, CD-ROM.

TE D

611

Campos Neto, M.C., 2000. Orogenic systems from Southwestern Gondwana: an approach to

616

Brasiliano-Pan African cycle and orogênic collage in Southeastern Brazil. In: U.G.

617

Cordani. E.J. Milani. A. Thomaz Filho, D.A. Campos. (Eds.): Tectonic Evolution of South

618

American. In: XXXI International Geological Congress. Rio de Janeiro. Brazil, 335-365.

620

Campos Neto. M.C., Caby, R., 2000. Lower crust extrusion and terrane acrection in the Neoproterozoic nappes of southeast Brazil. Tectonics, 19, 669-687.

AC C

619

EP

615

621

Campos Neto, M.C., Basei, M.A.S., Janasi, V.A., Moraes, R., 2011. Orogen migration and tectonic

622

setting of the Andrelândia Nappe system: An Ediacaran western Gondwana collage, south

623 624 625

of São Francisco craton. Journal of South American Earth Sciences, 32(4), 393-406.

Carneiro. C.D.R., 1983. Análise Estrutural do Grupo São Roque na Faixa entre o Pico do Jaraguá e a Serra dos Cristais. SP. Ph.D. thesis. Instituto de Geociências – USP..

626

Carneiro, C.D.R., Hasui, Y., Dantas, A.S.L., 1984. Contribuição ao Estudo da Litoestratigrafia do

627

Grupo São Roque na Faixa Jaraguá-Cristais - SP. In: XXXIII Congresso Brasileiro de

628

Geologia, Rio de Janeiro (RJ), Anais, 3212–3226.

19

ACCEPTED MANUSCRIPT 629

Cordani, U.G., Coutinho, J.M.V., Nutman, A.P., 2002. Geochronological constraints on the

630

evolution of the Embu Complex, Sao Paulo, Brazil. Journal of South American Earth

631

Sciences, 14(8), 903-910. Coutinho, J.M.V., Rodrigues, E de P., Suemitsu, A., Juliani, C., Beljavskis, P., Perosa, P.T.Y., 1982.

633

Geologia e Petrologia da Seqüência Vulcano-Sedimentar do Grupo São Roque na Serra de

634

Itaberaba – SP. In: XXXII Congresso Brasileiro de Geologia. Salvador – Bahia. Anais. 2,

635

624-640.

RI PT

632

636

Cox, R., Lowe, D.R., Cullers, R.L., 1995. The influence of sediment recycling and basement

637

composition on evolution of mudrock chemistry in the southwestern United States.

638

Geochimica et Cosmochimica Acta, 59(14), 2919-2940.

Cullers, R.L., 2000. The geochemistry of shales, siltstones and sandstones of Pennsylvanian-

640

Permian age, Colorado, USA: implications for provenance and metamorphic studies.

641

Lithos, 51, 181-203.

SC

639

Cullers, R.L., Barret, T., Carlson, R., Robinson, B., 1987. Rare earth element and mineralogic

643

changes in Holocene soil and stream sediment: a case study in the Wet Mountains,

644

Colorado, USA. Chemical Geology, 63, 275-297.

M AN U

642

645

Cullers, R.L., Berendsen, P., 1988. The provenance and chemical variation of sandstones associated

646

with the Mid-continental rift system, USA. European Journal of Mineralogy, 10, 987-

647

1002.

649

Cullers, R.L., Podkovyrov, N.V., 2002. The source and origin of terrigenous sedimentary rocks in

TE D

648

the Mesoproterozoic Ui group, southeastern Russia. Precambrian Research, 117, 157-183. Cury, L.F., Kaulfuss, G.A., Siga Jr, O., Basei, M.A.S., Harara, O.M.M., Sato, K., 2002. Idades U-Pb

651

(zircões) de 1.75 Ga em granitóides alcalinos deformados dos Núcleos Betara e Tigre:

652

Evidências de regimes extensionais do Estateriano na Faixa Apiaí. Geologia USP- Série

653

Científica, 2, 95-105.

EP

650

Dantas, E.L., Hackspacher, P., Godoy, A.M., Sato K., Pimentel, M.M., Oliveira, M.A.F., Fetter, A.,

655

2000. Characterization of the generating sources of continental crust of the Ribeira Belt

656 657

AC C

654

through isotope of Nd in the State of São Paulo, SE of Brazil In: South- American

Symposium on Isotope Geology. 2, Villa Carlos Paz, Argentina, Anais, 192-195.

658

Depaolo, D.J., 1988. Neodymium Isotope Geochemistry. An Introduction. Springer, Berlin. 187p.

659

Dott JR, R.H., 1964. Wacke. Graywacke and matrix – What approach to immature sandstone

660

classification? Journal of Sedimentary Petrology, 33(3), 625-632.

661

Elderfield, H., Greaves, M. J., 1982. The rare earth elements in seawater. Nature, 296, 214-219.

662

Faleiros, F.M., Campanha, G.A.C., Martins, L., Vlach, S.R.F., Vasconcelos, P.M., 2011. Ediacaran

663

high-pressure collision metamorphism and tectonics of the southern Ribeira Belt (SE

664

Brazil): Evidence for terrane accretion and dispersion during Gondwana assembly.

665

Precambrian Research, 189(3-4), 263-291.

20

ACCEPTED MANUSCRIPT 666

Fedo, C.M., Nesbitt, H.W., Young, G.M., 1995. Unraveling the effects of potassium metassomatism

667

in sedimentary rocks and paleosols, with implications for paleoweathering conditions and

668

provenance. Geology, Geological Society of America, 23, 921-924. Fetter, A.H., Hackspacker, P.C., Ebert, H.D., Dantas, E.L., Costa, A.C.D., 2001. New Sm/Nd and

670

U/Pb geochronological constraints on the Archean to Neoproterozoic evolution of the

671

Amparo basement complex of the central Ribeira belt, southeastern, Brazil. In: 3th South

672

American Symposium on Isotope Geology, Extend Abstracts, 125-128.

673 674

RI PT

669

Figueiredo, M.C.H., Bergmann, M., Penalva, F., Tassinari, C.C.G., 1982. Ocorrência de pillowlavas no Grupo São Roque. Estado de São Paulo. Revista Ciências da Terra, 2, 6-8.

Hackspacher, P.C., Dantas, E.L., Spoladore, A., Fetter, A.H., Oliveira, M.A.F., 2000. Evidence for

676

Neoproterozoic back-arc basin development in the Central Ribeira Belt, southeastern

677

Brazil: new geochronological and geochemical constraints from the São Roque-Açungui

678

Groups. Revista Brasileira de Geociências, 30, 110-114.

680 681 682 683 684

Harnois, L., 1988. The CIW index: a new chemical index of weathering. Sedimentary Geology, 55, 319-322.

M AN U

679

SC

675

Hasui, Y., Carneiro, C.D.R., Coimbra, A.M., 1975. The Ribeira Folded Belt. Revista Brasileira de Geociências, 5, 257-266.

Hasui. Y; Sadowski, G.R; Carneiro, C.D.R. 1976. Considerações Sobre a Estratigrafia do PréCambriano na Região de São Paulo. Boletim Instituto de Geociências – USP. 7, 107-112. Heilbron, M., Pedrosa-Soares, A.C., Campos Neto, M.C., Silva, L.C., Trouw, R.A.J., Janasi, V.A.,

686

2004. Brasiliano Orogens in Southeast and South Brazil. Journal of the Virtual Explorer,

687

17, Paper 4, Electronic Edition.

TE D

685

Heilbron, M., Valeriano, C.M., Tassinari, C.C.G., Almeida, J., Tupinamba, M., Siga, O., Jr., Trouw,

689

R., 2008. Correlation of Neoproterozoic terranes between the Ribeira Belt, SE Brazil and

690

its African counterpart: comparative tectonic evolution and open questions. Geological

691

Society, London, Special Publications, 294(1), 211-237.

EP

688

Henrique-Pinto, R., Janasi. V.A., 2010. Metaconglomerados e Rochas Associadas do Grupo São

693

Roque a Norte da Cidade de São Paulo. Brasil. Revista Brasileira de Geociências, 40(3),

694

AC C

692

409-425.

695

Henrique-Pinto, R., Janasi, V.A., Simonetti, A., Tassinari, C.C.G., Heaman, L.M., 2012.

696

Paleoproterozoic source contributions to the São Roque Group sedimentation: LA-MC-

697

ICPMS U-Pb dating and Sm-Nd systematics of clasts from metaconglomerates of the

698

Boturuna Formation. Geologia USP, 12(3), 21-32.

699

Henrique-Pinto, R. 2012. Proveniência e ambiente de sedimentação do Grupo São Roque com base

700

na química de rocha total e datação U-Pb de zircões detríticos. Ph.D. thesis, Universidade

701

de São Paulo, São Paulo.

21

ACCEPTED MANUSCRIPT 702 703

Henrique-Pinto, R., Janasi, V.A. 2014. Histórico do Conhecimento Geológico sobre o PréCambriano Paulista até o ano de 1955. Terrae Didática, 10(1), 52-66.

704

Henrique-Pinto, R., Janasi, V.A., Carvalho, B.B., Calado, B.O., Grohmann, C.H., 2014. Integrated

705

geological map of the São Roque Domain, North of São Paulo City - Brazil. Journal of

706

Maps, 1-6. Henrique-Pinto, R., Janasi, V.A., Vasconcellos, A.C.B.C., Sawyer, E.W., Barnes, S.-J., Basei,

708

M.A.S., Tassinari, C.C.G., 2015. Zircon provenance in meta-sandstones of the Sao Roque

709

Domain: implications for the Proterozoic evolution of the Ribeira Belt, SE Brazil,

710

Precambrian Research, 256, 271-288.

712

Herron, M. M., 1988. Geochemical classification of terrigenous sands and shales from core or log data. Journal of Sedimentary Research, 58(5), 820-829.

SC

711

RI PT

707

Juliani, C., Beljavskis, P., Schorscher, H.D., 1986. Petrogênese do Vulcanismo e Aspectos

714

Metalogenéticos Associados: Grupo Serra do Itaberaba na Região do São Roque – SP. In:

715

XXXIV Congresso Brasileiro de Geologia. Goiânia. Anais 2, 730-745.

716 717

M AN U

713

Juliani, C., Beljavskis, P., 1995. Revisão da litoestratigrafia da faixa São Roque/Serra do Itaberaba SP. Revista do Instituto Geológico, 16, 33-58.

Juliani, C., Hackspaker, P., Dantas, E.L., Fetter, A.H., 2000. The Mesoproterozoic volcano-

719

sedimentary Serra do Itaberaba Group of the central Ribeira Belt, São Paulo, Brazil:

720

implications for the age of the overlying São Roque Group. Revista Brasileira de

721

Geociências, 30, 82-86.

722 723

TE D

718

Kaulfuss, G.A., 2001. Geocronologia dos Núcleos de Embasamento Setuva. Betara e Tigre. Norte de Curitiba-Paraná. Master thesis. Instituto de Geociências – USP. Mantovani, M.S.M., Brito Neves, B.B., 2005. The Paranapanema Lithospheric Block: Its

725

Importance for Proterozoic (Rodinia, Gondwana) Supercontinent Theories. Gondwana

726

Research, 8(3), 303-315.

728 729 730

McBride, E.F., 1963. A classification of common sandstones. Journal of Sedimentary Petrology, 33(3), 664-669.

AC C

727

EP

724

McLennan, S.M., Hemming, S.R., 1991. Samarium/neodymium elemental and isotopic systematics in sedimentary rocks. Geochimica et Cosmochimica Acta, 56, 887-898.

731

McLennan, S.M., Taylor, S.R., McCulloch, M.T., Maynard, J.B., 1990. Geochemical and Nd-Sr

732

isotopic composition of deep-sea turbidites: Crustal evolution and plate tectonic

733

associations. Geochimica et Cosmochimica Acta, 54, 2015-2050.

734

McLennan, S.M., Hemming, S., McDaniel D.K., Hanson, G.N., 1993. Geochemical approaches to

735

sedimentation, provenance, and tectonics. Geological Society of America, Special Paper,

736

248, 21-40.

22

ACCEPTED MANUSCRIPT 737

McLennan, S.M., Hemming, S.R., Taylor, S.R., Eriksson, K.A., 1995. Early Proterozoic crustal

738

evolution: Geochemical and N-Pb isotopic evidence from metasedimentary rocks,

739

southwestern North America. Geochimica et Cosmochimica Acta, 59(6), 1153-1177.

740

Mori, P.E., Reeves, S., Correia, C.T., Haukka, M., 1999. Development of a fused glass disc XRF

741

facility and comparison with the pressed powder pellet technique at Instituto de

742

Geociências, Universidade de São Paulo. Revista Brasileira de Geociências, 29, 441-446. Navarro, M.S., Ulbrich, H.H.G.J., Andrade, S., Janasi, V.A., 2002. An adaptation of ICP-OES

744

routine determination techniques for the analysis of rare-earth elements by

745

chromatographic separation in geologic materials: tests with reference materials and

746

granitic rock. Journal of Alloys and Compounds, Amsterdam, 344, 40-45.

748

Nesbitt, H.W., Young, G.M., 1982. Early Proterozoic climates and plate motions inferred from

SC

747

RI PT

743

major element chemistry of lutites. Nature, 299, 715-717.

Nesbitt, H. W., Young, G.M. 1984. Prediction of some weathering trends of plutonic and volcanic

750

rocks based on thermodynamic and kinetic considerations. Geochimica et Cosmochimica

751

Acta, 48(7), 1523-1534.

752 753

M AN U

749

Nesbitt, H.W., Young, G.M., 1989. Formation and Diagenesis of Weathering Profiles. The Journal of Geology, 97(2), 129-147.

Nesbitt, H.W., Markovics, G., 1997. Weathering of granodioritic crust, long-term storage of

755

elements in weathering profiles, and petrogenesis of siliciclastic sediments. Geochimica et

756

Cosmochimica Acta, 6(8), 1653-1670.

TE D

754

757

Nesbitt, H.W., Young, G.M., McLennan, S.M., Keays, R.R., 1996. Effects of Chemical Weathering

758

and Sorting on the Petrogenesis of Siliciclastic Sediments, with Implications for

759

Provenance Studies. The Journal of Geology, 104(5), 525-542. Oliveira, M.A.F. de., Melo, R.P., Nardy, A.J.R., Arab, P.B., Trindade, I., 2008. New U/Pb

761

Palaeoproterozoic zircon age for the Cajamar metabasite, São Roque Group, Central

762

Ribeira Belt, Southeastern Brazil. In: VI South American Symposium on Isotope Geology.

763

San Carlos de Bariloche, Argentina, 1-4.

AC C

EP

760

764

Ribeiro, L.M de A.L., 2006. Estudo Geocronológico dos Terrenos Granito-Gnáissicos e Seqüências

765

Metavulcanossedimentares da Região do Betara (PR). Master thesis. Instituto de

766

Geociências – USP.

767

Roser, B.P., Korsch, R.J., 1988. Provenance signatures of sandstone-mudstone suites determined

768

using discriminant function analysis of major-element data. Chemical Geology, 67, 119-

769

139.

770 771

Sato, K., Tassinari, C.C.G., Kawashita, K., Petronilho, L., 1995. Método geocronológico Sm- Nd no IG-USP e suas aplicações. Anais da Academia Brasileira de Ciência, 67(3), 315-336.

23

ACCEPTED MANUSCRIPT 772

Sawyer, E.W., 1986. The influence of source rock type, chemical weathering and sorting on the

773

geochemistry of clastic sediments from the Quetico mesedimentary belt, Superior

774

Province, Canada. Chemical Geology, 55, 77-95.

775 776

Shimizu, H., Masuda, A., 1977. Cerium in chert as an indication of marine environment of its formation. Nature, 266, 346-348. Siga Jr, O., Basei, M.A.S., Passarelli, C.R., Harara, O.M., Sato, K., Cury, L.F., Prazeres Filho, H.J.,

778

2007. Geocronologia das Rochas Gnáissico-Migmatíticas e Sienograníticas do Núcleo

779

Setuva (PR): implicações tectônicas. Revista Brasileira de Geociências, 37(1), 114-128.

RI PT

777

Siga Jr, O., Basei, M.A.S., Sato, K., Passarelli, C.R., Nutman, A., McReath, I., Prazeres Filho,

781

H.J.D., 2011a. Calymmian (1.50-1.45 Ga) magmatic records in Votuverava and Perau

782

sequences, south-southeastern Brazil: Zircon ages and Nd-Sr isotopic geochemistry.

783

Journal of South American Earth Sciences, 32(4), 301-308.

SC

780

Siga Jr, O., Cury, L.F., McReath, I., Ribeiro, L.M.A.L., Sato, K., Basei, M.A.S. and Passarelli, C.R.,

785

2011b. Geology and geochronology of the Betara region in south-southeastern Brazil:

786

Evidence for possible Statherian (1.80-1.75 Ga) and Calymmian (1.50-1.45 Ga) extension

787

events. Gondwana Research, 19(1), 260-274.

M AN U

784

788

Siga Jr., O., Basei, M.A.S., Passarelli, C.R., Sato, K., Cury, L.F., McReath, I., 2009. Lower and

789

Upper Neoproterozoic magmatic records in Itaiacoca Belt (Paraná-Brazil): Zircon ages

790

and lithostratigraphy studies. Gondwana Research, 15(2), 197-208. Singh, P., Rajamani, V., 2001. REE geochemistry of recent clastic sediments from the Kaveri

792

floodplains, southern India: Implication to source area weathering and sedimentary

793

processes. Geochimica et Cosmochimica Acta, 65(18), 3093–3108.

TE D

791

Tassinari, C.C.G., Munhá, J.M.U., Ribeiro, A., Correia, C.T., 2001. Neoproterozoic oceans in the

795

Ribeira Belt (southeastern Brazil): The Pirapora do Bom Jesus ophiolitic complex:

796

Episodes, 24, 245-250.

EP

794

Taylor, S.R., McLennan, S.M., Armstrong, R.L., Tarney, J., 1981. The composition and evolution

798

of the continental crust: rare earth element evidence from sedimentary rocks (and

799 800 801

AC C

797

discussion). Phil. Trans. R. Soc. Lond., 301(1461), 381-399.

Taylor., S.R., and McLennan, S.M., 1985. The Continental Crust: Its Composition and Evolution. Blackwell. 298p.

802

Teixeira, W., Carneiro, M.A., Noce, C.M., Machado, N., Sato, K., Taylor, P.N., 1996. Pb, Sr and Nd

803

isotope constraints on the Archaean evolution of gneissic-granitoid complexes in the

804

southern São Francisco Craton, Brazil. Precambrian Research, 78, 151-164.

805

Teixeira, W., Ávila, C.A., Dussin, I.A., Neto, A.C., Bongiolo, E.M., Santos, J.O., Barbosa, N.S.

806

2015. A juvenile accretion episode (2.35-2.32 Ga) in the Mineiro belt and its role to the

807

Minas accretionary orogeny: zircon U-Pb-Hf and geochemical evidences. Precambrian

808

Research, 256, 148-169.

24

ACCEPTED MANUSCRIPT 809

Trouw, R.A.J., Peternel, R., Ribeiro, A., Heilbron, M., Vinagre, R., Duffles, P., Trouw, C.C.,

810

Fontainha, M., Kussama, H.H., 2013. A new interpretation for the interference zone

811

between the southern Brasília belt and the central Ribeira belt, SE Brazil. Journal of South

812

American Earth Sciences, 48, 43-57. Van Schmus, W.R., Tassinari, C.C.G., Cordani, U.G., 1986. Estudo geocronológico da parte inferior

814

do Grupo São Roque. In: XXXIV Congresso Brasileiro de Geologia. Goiânia (GO). Anais.

815

3, 1399-1406.

816

RI PT

813

Vauchez, A., Tommasi, A., Egydio-Silva, M., 1994. Self-indentation of a heterogeneous continental lithosphere. Geology, 22(11), 967-970.

817

Vlach, S.R.F., 2001. Microprobe monazite constraints for an early (ca. 790 Ma) Brasiliano Orogeny:

819

The Embu Terrane, Southeastern Brazil., III South American Symposium on Isotope

820

Geology. Extended Abstracts, Pucón, Chile, 26-268.

Westin, A., Campos Neto, M. C., 2013. Provenance and tectonic setting of the external nappe of the Southern Brasília Orogen. Journal of South American Earth Sciences, 48, 220-239.

822

M AN U

821

SC

818

823 824 825

FIGURE CAPTIONS

826

Figure 1: Simplified geological map of a portion of central-eastern Brazil, with emphasis on the

828

São Francisco Craton, its marginal sedimentary successions and the Ribeira Fold Belt (modified

829

from Bizzi, 2003).

830

Figure 2: (A)- Regional geological map modified from Campos Neto (2000). 1- Phanerozoic

831

sedimentary and associated Mesozoic intrusive rocks (Paraná Basin); 2- Neoproterozoic late and

832

post-orogenic granites; 3- (garnet)-(muscovite)-biotite granite; 4- porphyritic biotite granite; 5-

833

porphyritic (hornblende) biotite granite; 6- Socorro Guaxupé Domain (with predominance of

834

garnet-bearing migmatites); 7- Embu Domain: basement Paleoproterozoic gneisses; 8- Embu

835

Domain: cover metasupracrustal rocks; 9- Apiaí Terrane: São Roque and Açungui Groups; 10-

836

Serra do Itaberaba Group; 11- Costeiro Complex. (B)- Geological map of the central part of the

837

São Roque Domain and neighboring southernmost Socorro-Guaxupé Domain based in Henrique-

838

Pinto et al. (2014). 1- São Paulo Basin (Cenozoic); 2- Neoproterozoic shear zones with mylonite

839

and

840

(Neoproterozoic); 5- Socorro-Guaxupé Domain (paragneisses and migmatites); 6- Pirapora do Bom

841

Jesus Formation (metalimestones and metadolomites); 7= amphibolites, metatuffs and banded iron

842

formations (Pirapora do Bom Jesus Formation/Serra do Itaberaba Group (?)) ; 8-9- Serra do

843

Itaberaba Group (8= Kyanite-staurolite schists; 9= calc-silicate rocks and tremolite marbles); 10-

844

15- São Roque Group (10= metawackes; 11= metamudstones; 12= meta-quartzarenites and meta-

AC C

EP

TE D

827

ultramylonite;

3-

Undifferentiated

granites

(Neoproterozoic);

4-

quartz

sienite

25

ACCEPTED MANUSCRIPT subarkoses; 13= meta-feldspathic wackes and meta-quartzwackes; 14= metaconglomerates; 15=

846

acid metavolcanic rocks); 16- Basement (?) orthogneisses.

847

Figure 3: São Roque Domain samples plotted on ternary diagram (QFL) Q=quartz, F=feldspar,

848

L=lithic fragments; fields after McBride (1963) and Dott (1964).

849

Figure 4: Photomicrographs of metasedimentary rocks of São Roque Domain: A- meta-

850

quartzarenite; B- meta-subarkose; C- metarkose; D- meta-feldspathic wacke; E- meta-quartz

851

wacke; F- metamudstone (left, parallel polarizers; right, crossed polarizers).

852

Figure 5: Chemical classification diagram [log (SiO2/Al2O3) versus log(Fe2O3/K2O)] (Herron,

853

1988) for samples of the São Roque Domain.

854

Figure 6: Relationship between weathering intensity and sedimentary sorting: A- CIW=

855

[Al2O3/(Al2O3+CaO+N2O)*100] (Chemical Index Weathering – Harnois, 1988) x Al2O3 and B-

856

ICV= [(Fe2O3+MnO+MgO+CaO+N2O+K2O+TiO2)/Al2O3] (Index of Compositional Variability –

857

Cox et al., 1995) x CIA= [Al2O3/(Al2O3+CaO+N2O+K2O)*100] (Chemical Index of Alteration -

858

Nesbitt and Young, 1982).

859

Figure 7: Chemical composition of São Roque metasedimentary rocks in the A-CN-K diagram

860

(Nesbitt and Young, 1982). 1 – average granitic rocks, 2 – average adamellite, 3 – average

861

granodiorite, 4 – average tonalite, 5 – average gabbro (trends plotted according to Nesbitt and

862

Young, 1989).

863

Figure 8: Variation diagrams for major elements versus SiO2 in metasedimentary rocks of the São

864

Roque Domain. Fields 1 – 2 represent potential sources compiled from Kaulfuss (2001); basic,

865

granitic and sedimentary sources represent clasts of polymictic metaconglomerates of the Boturuna

866

Formation (Henrique-Pinto and Janasi, 2010).

867

Figure 9: Variation diagrams for trace elements versus SiO2 in metasedimentary rocks of the São

868

Roque Domain. 1 – 2 represent potential granitic sources compiled from Kaulfuss (2001); basic,

869

granitic and sedimentary sources represent clasts in polymictic metaconglomerates of the Boturuna

870

Formation (Henrique-Pinto and Janasi, 2010).

871

Figure 10: (A) - Chondrite-normalized (Taylor and McLennan, 1985) rare-earth element patterns

872

for metasedimentary rocks of São Roque Domain. Granitic and intermediate potential sources

873

compiled from Kaulfuss (2001), clasts of metaconglomerates compiled from Henrique-Pinto and

874

Janasi. (2010); (B) - Multi-elementary diagram using to discriminate felsic from mafic sources.

875

Values for La, Eu, Gd and Yb were normalized by chondrite (Taylor and McLennan, 1985).

876

Figure 11: (A) and (B) - Chondrite-normalized (Taylor and McLennan, 1985) rare-earth element

877

patterns, (C) and (D) - PAAS-normalized (Taylor et al., 1981) rare-earth element patterns. Average

878

of metawackes and metamudstones from the São Roque Domain. PM= Passive Margin; OIA=

879

Oceanic Island Arc; CIA= Continental Island Arc, by Shimizu and Masuda (1977).

880

Figure 12: São Roque Domain samples plotted on K2O/Na2O vs. SiO2 and SiO2/Al2O3 vs.

881

K2O/Na2O provenance signature discrimination diagram of Roser and Korsch (1988).

AC C

EP

TE D

M AN U

SC

RI PT

845

26

ACCEPTED MANUSCRIPT Figure 13: (A) - Plot of ƐNd versus Th/Sc ratio (McLennan et al., 1990) and (B) - Plot of ƒSm/Nd

883

versus ƐNd (McLennan and Hemming, 1991) for metamudstones of the Piragibu Formation, São

884

Roque Domain.

885

Figure 14: (A) ƐNd versus TDM (Ga) diagram for metamudstones of Piragibu Formation (including

886

one sample of meta-felspathic wacke from Boturuna Formation; Henrique-Pinto et al., 2012), São

887

Roque Domain; DM: evolution line of depleted mantle (De Paolo, 1988); (B) histogram with peaks

888

of TDM ages (including samples compiled from Dantas et al., 2000) and (C) population of detrital

889

zircons of São Roque Domain from Henrique-Pinto et al. (2015).

890 891

TABLE CAPTIONS

SC

892

RI PT

882

Table 1: Modal mineralogy of metasedimentary rocks of São Roque Domain (500 points per

894

section).

895

Table 2: Results of chemical analyses (XRF) of metasedimentary rocks of the São Roque Domain.

896

n.a.= not analysed;