The Barreiro suite in the central Ribeira Belt (SE-Brazil): a late Tonian tholeiitic intraplate magmatic event in the distal passive margin of the São Francisco Paleocontinent

Heilbron, Monica; Oliveira, Caroline; Lobato, Marcela; Valeriano, Claudio de Morisson; Dussin, Ivo; Dantas, Elton; Simonetti, Antonio; Bruno, Henrique; Corrales, Felipe; Socoloff, Eduardo

doi:10.1590/2317-4889201920180129

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Sumário

ARTICLE • Braz. J. Geol. 49 (02) • 2019 • https://doi.org/10.1590/2317-4889201920180129 linkcopy

The Barreiro suite in the central Ribeira Belt (SE-Brazil): a late Tonian tholeiitic intraplate magmatic event in the distal passive margin of the São Francisco Paleocontinent

Authorship SCIMAGO INSTITUTIONS RANKINGS

New geochemical, U-Pb, Lu-Hf and Sr-Nd data from the Barreiro Suite metabasites in comparison with enclaves within the distal Andrelândia Group and the orthogranulites of the Juiz de Fora Complex are presented. Geochemical data suggest intraplate setting, with high and low-TiO₂ , TDM_Nd ages between 1.80 and 1.41 Ga, negative ΕNd_t and (⁸⁷ Sr/⁸⁶ Sr)i between 0.714 and 0.747. Results contrast with part of the Juiz de Fora Complex enclaves, with island arc tholeiites- calcalkaline basalts (IAT-CAB) geochemical signatures, TDM_Nd ages between 2.58 and 2.16 Ga, positive ΕNd_t values and (87Sr/86Sr)_i between 0.700 and 0.712. U-Pb data for the Barreiro Suite yielded a crystallization age of 766 ± 13 Ma and a metamorphic overprint of 619 ± 6 Ma. The results indicate three episodes of mafic magmatism in the Occidental terrane of the Ribeira Belt. The two older episodes are related to Rhyacian arc evolution (ca. 2.2 to 2.1 Ga) and to the Statherian (ca. 1.7 Ga) tectonics, and occur only within the Juiz de Fora Complex, while the younger ca. 766 Ma episode constrains the timing of distal passive margin evolution. An important implication is that these late Tonian metabasic rocks could have been a source of detrital zircons for the sedimentation along the distal Andrelândia basin.

KEYWORDS:
Andrelândia Group; U-Pb; Sm-Nd; Lu-Hf; within-plate basalts

Geochemical Data: Major Elements
Sample	type	Unit	SiO₂	Al₂O₃	FeO	Fe2O3t	MnO	MgO	CaO	Na₂O	K₂O	TiO₂	P₂O₅	LOI	Total
RE-CE-15	HTiO₂	BS	53.51	14.66	11.57	12.86	0.274	4.24	9.2	1.65	0.25	2.608	1.35	0.18	100.8
RE-CE-16	HTiO₂	BS	52.05	13.95	13.98	15.54	0.313	2.97	7.05	3.41	1.16	3.03	0.91	-0.02	100.4
RE-CE-19	HTiO₂	BS	48.74	15.92	12.67	14.08	0.215	5.19	8.19	3.2	0.74	3.117	0.64	0.46	100.5
RE-CE-30B	HTiO₂	BS	48.65	15.08	12.2	13.56	0.248	5.96	8.61	2.84	0.6	3.767	1.08	-0.28	100.1
RE-CE-2A	HTiO₂	BS	49.19	14.46	12.05	13.39	0.223	4.73	7.92	3.31	0.98	2.437	0.5	1.5	98.65
RE-CE-12	HTiO₂	BS	54.48	13.75	12.33	13.7	0.236	2.93	6.66	3.23	1.7	2.815	0.89	-0.1	100.3
RE-CE-13B	HTiO₂	BS	51.45	15.6	12.12	13.47	0.267	4.51	7.61	3.48	0.93	2.762	0.63	0.04	100.7
RE-CE-27C	HTiO₂	BS	51.02	15.41	12.57	13.97	0.223	3.34	6.75	3.46	2.18	2.832	0.76	0.29	100.2
RE-CE-28C	HTiO₂	BS	49.5	17.16	10.53	11.7	0.193	5.91	8.45	3.53	1.11	2.238	0.38	0.54	100.7
RE-CE-29	HTiO₂	BS	50.58	16.31	11.23	12.48	0.204	4.82	7.77	3.54	1.46	2.42	0.58	0.46	100.6
RE-CE-30A	HTiO₂	BS	50.05	15.32	12.99	14.44	0.225	4.01	7.53	3.09	1.6	3.013	0.78	0.3	100.4
RE-CE-70B	HTiO₂	BS	47.98	16.31	13	14.45	0.22	4.84	7.98	3.13	0.71	2.948	0.7	-0.21	99.05
RE-CE-3A	LTiO₂	BS	51.81	16.42	9.76	10.85	0.181	5.76	8.56	3.4	0.74	1.919	0.36	0.96	101
RE-CE-03B	LTiO₂	BS	48.67	17.22	9.65	10.72	0.188	7.45	9.79	3.03	0.48	1.586	0.28	1.06	100.5
RE-CE-25	LTiO₂	BS	51.99	16.83	9.71	10.79	0.174	5.49	7.53	3.59	1.55	1.86	0.33	0.62	100.8
RE-CE-68	LTiO₂	BS	57.34	15.8	9.3	10.34	0.157	3.84	6.13	3.39	0.63	1.776	0.41	0.3	100.1
RE-CE-3C	LTiO₂	BS	49.41	17.39	9.51	10.57	0.174	6.63	9.3	3.14	0.86	1.679	0.32	0.98	100.4
RE-CE-11	LTiO₂	BS	51.24	17.26	9.89	10.99	0.18	5.62	8.69	3.25	0.63	1.764	0.39	0.69	100.7
RE-CE-149	LTiO₂	BS	52.7	16.94	10.19	11.32	0.186	6.03	7.76	3.38	0.68	1.724	0.3	-0.07	100.9
MI-BR-39	LTiO₂	AND	48	13.88	12.76	14.18	0.21	7.3	11.88	1.41	0.54	1.386	0.1	-0.13	98.75
MI-BE-87B	LTiO₂	AND	50.84	15.02	8.9	9.89	0.16	9.57	7.8	2.65	1.87	1.426	0.46	0.67	100.4
PA-BE-133B	LTiO₂	AND	49.01	19.04	8.98	9.98	0.156	5.67	8.8	3.47	1.22	1.697	0.29	0.56	99.88
MI-BR-54	LTiO₂	JF	40.45	12.52	14.06	15.62	0.301	21.58	6.92	0.51	0.31	0.348	0.09	0.68	99.32
MI-VIII-15	LTiO₂	JF	46.8	9.98	9.57	10.64	0.155	21.07	8.98	1.28	0.19	0.335	0.03	1.28	100.7
SP-BR-16	LTiO₂	JF	48.84	13.79	13.35	14.84	0.206	6.64	10.85	2.78	0.93	1.435	0.1	0.28	100.7
MI-II-62	LTiO₂	JF	49.81	15.24	12.09	13.44	0.172	6.63	9.98	3.22	0.95	0.974	0.14	0.14	100.7
MI-V-40	LTiO₂	JF	46.14	14.95	11.12	12.36	0.25	8.31	12.6	2.64	1.17	1.058	0.28	1.04	100.8
MI-BL-27	LTiO₂	JF	51.01	14.8	9.37	10.41	0.167	7.58	11.9	1.92	0.65	0.934	0.12	0.88	100.4
PA-BE-146	LTiO₂	JF	50.82	13.84	10.88	12.09	0.233	7.76	10.11	2.69	0.71	1.146	0.41	0.11	99.93
PA-BE-136	LTiO₂	JF	50.85	15.32	9.75	10.83	0.163	7.41	7.6	3.17	2.39	1.024	0.48	0.09	99.31
SP-BR-06A	LTiO₂	JF	50.07	14.36	11.58	12.87	0.185	7.25	8.52	2.82	1.19	0.948	0.23	1.19	99.65
PA-BE-137A	LTiO₂	JF	51.27	10.61	10.13	11.26	0.203	12.84	8.85	2.04	2.32	0.629	0.39	0.24	100.7
SP-BR-06C	LTiO₂	JF	42.48	18.52	10.95	12.17	0.138	6.24	12.23	2.44	1.44	1.585	1.05	0.99	99.28
SP-BR-17B	LTiO₂	JF	49.22	14.16	12.62	14.02	0.187	7.02	11.23	2.33	0.68	1.356	0.11	0.02	100.3
MI-BR-19C	LTiO₂	JF	48.56	13.65	13.49	14.99	0.217	6.59	10.03	2.64	1.3	1.557	0.12	0.69	100.3
MI-BR-19E	LTiO₂	JF	51.26	14.41	12.26	13.62	0.265	5.4	5.28	2.33	3.35	1.538	0.13	1.35	98.93
PA-BE-92D	LTiO₂	JF	44.68	12.52	14.75	16.39	0.247	11.73	8.2	1.56	3.7	0.343	0.04	1.46	100.9
MI-BE-83A	LTiO₂	JF	52.16	16.3	9	10.01	0.165	4.99	7.32	3.64	1.42	1.621	0.32	1.2	99.15
MI-IX-03B	HTiO₂	JF	51.62	16.41	9.79	10.88	0.156	5.22	7.89	3.15	1.79	2.157	0.86	0.27	100.4
MI-VIII-65	HTiO₂	JF	46.78	18.07	9.6	10.67	0.166	4.72	9	3.39	2.57	2.245	1.15	0.57	99.35
MI-III-18	HTiO₂	JF	49.11	16.98	11.45	12.72	0.2	5	8.63	3.23	0.68	2.467	0.81	0.07	99.89
MI-BR-56	HTiO₂	JF	51.05	16.62	11.4	12.67	0.201	4.03	8.09	3.37	1.48	2.465	1.13	-0.24	100.9
Geochemical Data: Trace Elements
Sample	Type	Unit	Sc	Be	V	Ba	Sr	Y	Zr	Cr	Co	Ni	Cu	Zn	Ga	Ge	As	Rb	Nb
RE-CE-15	HTiO₂	BS	26	5	252	230	593	44	354	200	30	60	20	160	24	2	6	5	29
RE-CE-16	HTiO₂	BS	30	2	250	1089	553	49	342	20	34	30	40	180	22	1	< 5	8	28
RE-CE-19	HTiO₂	BS	30	1	262	657	610	34	174	30	44	30	40	120	21	1	< 5	3	19
RE-CE-30B	HTiO₂	BS	31	1	347	446	569	34	159	70	34	30	30	130	18	1	< 5	7	23
RE-CE-2A	HTiO₂	BS	27	2	225	775	507	39	287	20	39	20	30	140	21	2	< 5	8	20
RE-CE-12	HTiO₂	BS	28	2	227	1364	528	52	430	< 20	30	< 20	30	170	23	2	< 5	16	28
RE-CE-13B	HTiO₂	BS	30	2	211	677	573	40	317	50	38	30	30	130	21	2	< 5	15	20
RE-CE-27C	HTiO₂	BS	28	2	224	1605	498	50	545	< 20	31	< 20	30	140	23	1	< 5	24	31
RE-CE-28C	HTiO₂	BS	27	2	224	299	556	30	221	40	42	< 20	30	90	20	1	< 5	15	15
RE-CE-29	HTiO₂	BS	27	2	229	1147	622	36	573	< 20	38	20	30	110	20	1	< 5	29	19
RE-CE-30A	HTiO₂	BS	30	2	261	1377	553	48	510	< 20	36	< 20	30	140	22	1	< 5	13	27
RE-CE-70B	HTiO₂	BS	27	2	239	732	619	37	299	< 20	45	< 20	30	140	26	2	< 5	6	20
RE-CE-3A	LTiO₂	BS	26	2	207	466	626	20	153	70	37	30	40	100	20	1	< 5	9	12
RE-CE-03B	LTiO₂	BS	28	1	180	353	585	23	92	100	42	40	20	80	17	1	< 5	3	9
RE-CE-25	LTiO₂	BS	25	2	187	437	537	30	225	40	37	30	30	90	19	1	< 5	67	13
RE-CE-68	LTiO₂	BS	23	2	170	372	427	28	152	30	29	< 20	20	100	25	2	< 5	5	18
RE-CE-3C	LTiO₂	BS	28	1	212	504	627	29	177	140	37	60	30	80	18	1	< 5	9	11
RE-CE-11	LTiO₂	BS	27	2	220	711	646	27	257	30	37	30	30	100	19	1	< 5	5	12
RE-CE-149	LTiO₂	BS	24	1	171	427	641	20	81	60	38	40	30	90	21	2	< 5	6	3
MI-BR-39	LTiO₂	AND	41	< 1	369	12	146	19	57	150	64	90	30	120	19	2	< 5	7	4
MI-BE-87B	LTiO₂	AND	26	2	186	1475	711	26	228	590	44	230	60	90	17	2	< 5	57	14
PA-BE-133B	LTiO₂	AND	25	2	189	441	587	24	180	40	35	30	20	60	20	2	< 5	34	3
MI-BR-54	LTiO₂	JF	14	< 1	75	327	114	12	13	200	114	450	60	280	9	1	< 5	4	1
MI-VIII-15	LTiO₂	JF	33	< 1	186	22	35	19	20	2020	70	870	< 10	50	8	2	< 5	< 2	1
SP-BR-16	LTiO₂	JF	39	< 1	392	64	131	31	73	90	56	90	10	120	20	2	< 5	8	4
MI-II-62	LTiO₂	JF	36	< 1	253	207	264	20	87	90	49	140	30	110	20	2	< 5	5	4
MI-V-40	LTiO₂	JF	45	2	331	399	286	16	94	410	45	90	< 10	120	19	2	< 5	21	3
MI-BL-27	LTiO₂	JF	40	< 1	285	181	202	18	80	310	42	90	90	70	17	2	< 5	19	6
PA-BE-146	LTiO₂	JF	43	1	170	1164	643	32	102	490	35	110	40	100	18	2	< 5	16	< 1
PA-BE-136	LTiO₂	JF	26	2	192	1141	739	22	139	280	35	80	< 10	100	19	2	< 5	55	< 1
SP-BR-06A	LTiO₂	JF	47	3	213	165	324	58	188	210	42	100	10	310	23	2	< 5	15	13
PA-BE-137A	LTiO₂	JF	30	1	160	880	464	25	146	1000	42	260	< 10	110	15	2	< 5	72	< 1
SP-BR-06C	LTiO₂	JF	32	< 1	389	256	765	34	60	30	50	< 20	60	80	22	1	< 5	32	5
SP-BR-17B	LTiO₂	JF	40	< 1	358	221	276	21	77	130	67	130	140	130	19	2	< 5	4	4
MI-BR-19C	LTiO₂	JF	43	1	419	134	250	30	81	110	54	80	30	150	22	2	< 5	12	10
MI-BR-19E	LTiO₂	JF	41	3	200	690	272	83	100	90	40	50	30	190	27	3	< 5	235	47
PA-BE-92D	LTiO₂	JF	27	3	180	352	53	23	32	720	54	420	< 10	280	19	2	< 5	157	9
MI-BE-83A	LTiO₂	JF	24	2	183	488	494	26	239	< 20	33	20	20	90	19	2	< 5	34	11
MI-IX-03B	HTiO₂	JF	19	< 1	237	1070	673	22	148	70	36	60	30	90	18	2	< 5	35	9
MI-VIII-65	HTiO₂	JF	28	4	253	1521	1392	39	252	30	15	< 20	10	120	24	2	< 5	75	23
MI-III-18	HTiO₂	JF	30	1	266	613	639	36	187	< 20	37	30	30	130	22	2	< 5	9	20
MI-BR-56	HTiO₂	JF	29	2	235	1252	674	49	655	40	29	30	30	140	22	2	< 5	16	31
Geochemical data: Trace and Rare Earth Elements (REE)
Sample	Type	Unit	La	Ce	Pr	Nd	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb	Lu	Hf	Ta	Pb	Th	U
RE-CE-15	HTiO₂	BS	67	142	17.8	75.1	15.3	4.42	12.7	1.8	9.5	1.8	4.9	0.65	4	0.57	7.7	1.6	7	4.5	1.6
RE-CE-16	HTiO₂	BS	52.2	114	15.1	65.2	13	3.77	11.5	1.7	9.5	1.8	5.3	0.76	4.8	0.7	6.9	1.5	6	0.8	0.2
RE-CE-19	HTiO₂	BS	28.8	64	8.58	36.7	8	2.57	7.3	1.1	6.5	1.3	3.4	0.49	3	0.43	3.7	1	< 5	0.2	< 0.1
RE-CE-30B	HTiO₂	BS	36.7	81.8	10.9	44.9	9.1	2.08	7.8	1.1	6.2	1.2	3.1	0.42	2.5	0.38	3.4	1.3	< 5	0.8	0.1
RE-CE-2A	HTiO₂	BS	35.3	74.5	9.61	40.5	8.6	2.71	9	1.3	7.4	1.5	4.2	0.58	3.6	0.56	5.9	1	7	0.4	0.2
RE-CE-12	HTiO₂	BS	59.2	130	17.1	70.8	14.7	3.66	13.1	1.9	10.8	2.1	5.8	0.79	4.9	0.72	8.9	1.5	7	0.5	0.2
RE-CE-13B	HTiO₂	BS	35.8	77.5	10.1	42.8	9.3	2.61	9.1	1.3	7.7	1.5	4.4	0.6	3.7	0.55	6.1	1.1	6	0.6	0.2
RE-CE-27C	HTiO₂	BS	59.4	125	16.1	65.4	13	3.8	11.3	1.7	9.7	1.8	5.2	0.72	4.3	0.64	10.1	1.4	9	0.9	0.2
RE-CE-28C	HTiO₂	BS	20.1	44.4	5.88	25.6	6.1	2.15	5.6	0.9	5.5	1.1	3.1	0.46	2.9	0.42	4.6	1	< 5	1.2	0.4
RE-CE-29	HTiO₂	BS	40.8	84.4	10.5	42	8.4	2.83	7.6	1.1	6.9	1.3	3.8	0.53	3.3	0.5	10.1	1	6	0.8	0.2
RE-CE-30A	HTiO₂	BS	53.5	114	14.8	60.2	12.1	3.56	11	1.6	9.2	1.8	4.9	0.7	4.3	0.64	9.7	1.3	8	1	0.2
RE-CE-70B	HTiO₂	BS	37.5	81.7	10.8	47.2	10.1	3.1	9.6	1.6	8.6	1.6	4.5	0.67	4	0.59	6.2	1.2	5	0.3	0.1
RE-CE-3A	LTiO₂	BS	24.9	50.6	6.51	26.5	5.5	1.83	5.1	0.7	4.3	0.8	2.3	0.33	2.1	0.31	3.4	0.6	6	0.5	0.1
RE-CE-03B	LTiO₂	BS	18.1	38.8	5.08	21.5	4.9	1.87	5	0.8	4.4	0.9	2.6	0.36	2.2	0.31	2.3	0.5	< 5	0.5	0.1
RE-CE-25	LTiO₂	BS	24.9	50.8	6.53	27	5.8	1.96	6	1	5.9	1.1	3.3	0.46	3	0.44	4.6	0.7	8	2.9	0.8
RE-CE-68	LTiO₂	BS	34.9	73.9	9.61	38.5	8	2.02	7.6	1.3	6.8	1.2	3.3	0.51	3	0.38	3.7	1.1	11	4.1	0.9
RE-CE-3C	LTiO₂	BS	27.2	60.4	7.89	32.6	7.1	2.01	6.5	1	5.9	1.2	3.3	0.45	2.8	0.41	4	0.5	< 5	0.9	0.2
RE-CE-11	LTiO₂	BS	35.2	67.1	8.42	35.1	6.9	2.29	6.6	1	5.4	1.1	3.1	0.43	2.7	0.37	5.5	0.4	7	0.5	0.1
RE-CE-149	LTiO₂	BS	17.2	35.8	4.69	20.3	4.2	1.84	4.1	0.7	3.7	0.7	2	0.3	1.9	0.28	1.5	0.7	< 5	0.1	< 0.1
MI-BR-39	LTiO₂	AND	6.4	17	2.52	12	3.4	1.13	3.7	0.7	4	0.8	2.3	0.34	2.1	0.34	1.6	0.4	< 5	1.6	0.2
MI-BE-87B	LTiO₂	AND	59.4	111	12.7	45.2	7.9	2.07	5.5	0.8	4.5	0.9	2.5	0.38	2.4	0.37	4.1	0.6	9	9.9	1.2
PA-BE-133B	LTiO₂	AND	18.4	38	4.87	20.7	4.8	1.61	4.6	0.8	4.6	0.9	2.6	0.41	2.5	0.38	3.6	0.9	< 5	2.3	0.4
MI-BR-54	LTiO₂	JF	8.2	5	2.12	8.7	2.1	0.7	2.2	0.4	2.5	0.5	1.3	0.2	1.3	0.21	0.4	0.1	< 5	0.4	0.1
MI-VIII-15	LTiO₂	JF	12.1	4.2	3.76	15.9	3.9	1.11	3.3	0.6	3.7	0.7	2	0.31	2	0.28	0.5	< 0.1	< 5	0.4	0.2
SP-BR-16	LTiO₂	JF	22.3	16.7	6.05	25.2	6.3	1.99	6.5	1.1	6.6	1.3	3.5	0.5	3.2	0.49	1.9	0.3	< 5	0.4	0.1
MI-II-62	LTiO₂	JF	11.7	22.6	3.12	12.8	3.2	0.99	3.7	0.6	3.9	0.8	2.4	0.38	2.4	0.33	2.2	0.3	< 5	0.6	0.1
MI-V-40	LTiO₂	JF	15.3	33.6	4.41	18.6	4.3	1.22	3.9	0.6	3.1	0.6	1.8	0.28	1.8	0.25	2	0.3	8	1.2	0.3
MI-BL-27	LTiO₂	JF	10	21	2.76	12.1	2.9	0.97	3.1	0.5	3.2	0.6	1.8	0.26	1.7	0.24	1.8	0.3	< 5	1.8	0.4
PA-BE-146	LTiO₂	JF	31.9	65.5	8.65	36.9	8	2.25	7.4	1.1	6.4	1.2	3.4	0.51	3	0.44	2.6	0.5	< 5	1.4	0.2
PA-BE-136	LTiO₂	JF	23.7	53.3	7.34	31.3	6.7	1.66	5.5	0.8	4.4	0.8	2.4	0.37	2.2	0.3	3.1	0.5	8	0.1	0.1
SP-BR-06A	LTiO₂	JF	39	104	15.1	66.5	16	2.26	13.3	2.1	11.2	2	5.4	0.76	4.5	0.68	4.1	0.9	6	2.7	1.6
PA-BE-137A	LTiO₂	JF	23.3	56.7	8.08	34.6	7.4	1.59	5.9	0.8	4.5	0.9	2.4	0.4	2.5	0.36	3.1	0.6	< 5	0.3	0.3
SP-BR-06C	LTiO₂	JF	22.4	57.8	8.87	42.6	10	2.61	9.2	1.4	7.3	1.4	3.8	0.51	3	0.46	1.9	0.3	< 5	1.7	0.7
SP-BR-17B	LTiO₂	JF	5.4	13.2	2.16	10.7	3.2	1.13	3.8	0.7	4.2	0.8	2.4	0.35	2.3	0.37	1.8	0.3	< 5	0.3	< 0.1
MI-BR-19C	LTiO₂	JF	24.9	55.9	6.86	25.7	6	1.77	5.9	1.1	6.2	1.2	3.3	0.5	3.2	0.5	2.2	0.7	7	1.1	0.1
MI-BR-19E	LTiO₂	JF	53.5	155	23.3	99.4	23.1	2.06	19.1	3.1	17	3.2	8.8	1.34	8.4	1.28	3.1	2.1	12	4.8	0.3
PA-BE-92D	LTiO₂	JF	10.3	23.8	3.22	13.2	3.4	1.13	3	0.6	3.6	0.8	2.4	0.39	2.5	0.4	0.9	0.3	< 5	2.5	0.6
MI-BE-83A	LTiO₂	JF	27.5	55.7	6.91	28.1	5.9	1.85	5.1	0.8	4.8	0.9	2.6	0.39	2.5	0.37	4.2	0.6	7	1.4	0.3
MI-IX-03B	HTiO₂	JF	27.6	60.4	7.96	34.5	6.6	1.89	5.7	0.8	4.3	0.8	2.1	0.3	1.8	0.26	2.7	0.5	< 5	1	0.2
MI-VIII-65	HTiO₂	JF	60.8	132	17.3	73.9	14.9	3.52	10.8	1.6	7.7	1.3	3.6	0.52	3.1	0.42	4.9	1.1	8	4.2	1
MI-III-18	HTiO₂	JF	33.2	76	10.3	45.7	9.4	2.51	7.9	1.2	6.9	1.3	3.5	0.56	3.3	0.44	3.5	0.9	< 5	0.3	< 0.1
MI-BR-56	HTiO₂	JF	62.6	139	18.8	76.6	15.2	3.02	12.6	1.8	9.6	1.7	4.8	0.73	4.5	0.63	11.8	1.2	8	0.9	0.1

Spot/	Th ppm	U ppm	Pb ppm	Th/U	_ƒ -206	Ratios							Age (Ma)						Discordance %
Spot/	Th ppm	U ppm	Pb ppm	Th/U	_ƒ -206	²⁰⁷ *Pb/** ²³⁵ U	1σ	²⁰⁶ *Pb/** ²³⁸ U	1σ	Rho	²⁰⁷ *Pb/** ²⁰⁶ Pb*	1σ	²⁰⁶ Pb/ ²³⁸ U	1σ	²⁰⁷ Pb/ ²³⁵ U	1σ	²⁰⁷ Pb/ ²⁰⁶ Pb	1σ	Discordance %
Z-01	176	360	41	0.49	0.0009	0.81869	3.63	0.09884	3.10	0.85	0.06008	1.89	608	19	607	22	606	11	0
Z-02	132	96	14	1.38	0.0031	1.03905	4.70	0.12048	2.83	0.60	0.06255	3.75	733	21	723	34	693	26	-6
Z-03	71	298	41	0.24	0.0007	1.17151	2.42	0.13013	1.77	0.73	0.06529	1.66	789	14	787	19	784	13	-1
Z-04	150	350	39	0.43	0.0010	0.88157	2.65	0.10567	1.98	0.75	0.06051	1.77	648	13	642	17	622	11	-4
Z-05	57	77	10	0.75	0.0027	0.81597	5.96	0.09855	4.61	0.77	0.06005	3.77	606	28	606	36	605	23	0
Z-06	200	346	38	0.58	0.0007	0.81093	3.33	0.09780	2.82	0.85	0.06014	1.77	602	17	603	20	608	11	1
Z-07	12	66	17	0.18	0.0019	2.91376	2.67	0.23946	2.16	0.81	0.08825	1.56	1384	30	1385	37	1388	22	0
Z-08	45	333	44	0.14	0.0006	1.17653	2.83	0.13035	2.33	0.82	0.06546	1.60	790	18	790	22	789	13	0
Z-09	41	687	70	0.06	0.0005	0.79912	3.71	0.09649	3.35	0.90	0.06007	1.58	594	20	596	22	606	10	2
Z-10	66	155	18	0.43	0.0018	0.85099	4.27	0.10161	3.17	0.74	0.06074	2.86	624	20	625	27	630	18	1
Z-11	22	1005	96	0.02	0.0003	0.78038	3.72	0.09518	3.34	0.90	0.05947	1.64	586	20	586	22	584	10	0
Z-12	26	168	21	0.16	0.0012	1.07514	3.36	0.12121	2.42	0.72	0.06433	2.33	738	18	741	25	753	18	2
Z-13	25	40	8	0.63	0.0026	0.84299	6.07	0.10107	4.51	0.74	0.06049	4.06	621	28	621	38	621	25	0
Z-14	30	46	8	0.65	0.0048	1.18654	6.45	0.13132	4.74	0.73	0.06553	4.38	795	38	794	51	791	35	0
Z-15	140	217	24	0.65	0.0012	0.80498	3.64	0.09731	2.91	0.80	0.06000	2.18	599	17	600	22	603	13	1
Z-16	52	276	30	0.19	0.0010	0.81484	4.23	0.09851	3.84	0.91	0.05999	1.77	606	23	605	26	603	11	0
Z-17	79	351	38	0.23	0.0010	0.81989	3.67	0.09884	3.24	0.88	0.06016	1.73	608	20	608	22	609	11	0
Z-18	14	331	32	0.04	0.0015	0.82274	3.71	0.09891	3.24	0.87	0.06033	1.80	608	20	610	23	615	11	1
Z-19	39	69	8	0.58	0.0025	0.82829	7.43	0.09977	5.68	0.76	0.06021	4.78	613	35	613	45	611	29	0
Z-20	82	62	9	1.33	0.0044	1.16436	5.89	0.12907	4.55	0.77	0.06543	3.75	783	36	784	46	788	30	1
Z-21	67	455	42	0.15	0.0009	0.91080	2.90	0.10738	2.25	0.78	0.06152	1.83	658	15	657	19	657	12	0
Z-22	56	173	16	0.33	0.0023	0.81295	4.73	0.09820	3.68	0.78	0.06004	2.96	604	22	604	29	605	18	0
Z-23	45	297	26	0.15	0.0012	0.81363	3.83	0.09815	3.04	0.79	0.06013	2.33	604	18	604	23	608	14	1
Z-24	51	92	12	0.55	0.0025	1.03636	7.44	0.11878	6.17	0.83	0.06328	4.15	724	45	722	54	718	30	-1
Z-25	2	28	2	0.08	0.0119	0.72127	19.74	0.08933	14.3	0.72	0.05856	13.7	552	79	551	109	551	75	0
Z-26	151	183	70	0.83	0.0004	7.44485	1.85	0.39657	1.39	0.76	0.13616	1.21	2153	30	2166	40	2179	26	1
Z-27	9	17	6	0.51	0.0023	7.24563	6.67	0.39303	4.15	0.62	0.13370	5.23	2137	89	2142	143	2147	112	0
Z-28	44	156	15	0.29	0.0024	0.94416	4.48	0.11023	3.69	0.82	0.06212	2.55	674	25	675	30	678	17	1
Z-29	69	115	12	0.60	0.0026	0.89659	5.08	0.10611	3.70	0.73	0.06128	3.49	650	24	650	33	649	23	0
Z-30	44	338	30	0.13	0.0009	0.81589	3.90	0.09824	3.41	0.88	0.06023	1.89	604	21	606	24	612	12	1
Z-31	29	121	9	0.25	0.0016	0.84257	5.18	0.10108	3.44	0.66	0.06046	3.87	621	21	621	32	620	24	0
Z-32	21	99	9	0.22	0.0024	1.08145	5.02	0.12212	3.27	0.65	0.06423	3.81	743	24	744	37	749	29	1
Z-33	60	166	14	0.36	0.0018	0.83414	4.90	0.10011	4.31	0.88	0.06043	2.33	615	26	616	30	619	14	1
Z-34	45	241	20	0.19	0.0008	0.84907	4.00	0.10167	3.26	0.82	0.06057	2.31	624	20	624	25	624	14	0
Z-35	57	263	24	0.22	0.0014	0.83449	3.34	0.10021	2.76	0.83	0.06039	1.88	616	17	616	21	618	12	0
Z-36	7	627	51	0.01	0.0005	0.83278	3.30	0.10023	2.81	0.85	0.06026	1.72	616	17	615	20	613	11	0
Z-37	29	87	8	0.34	0.0030	0.83633	6.24	0.10043	5.03	0.81	0.06040	3.69	617	31	617	38	618	23	0
Z-38	262	202	28	1.30	0.0013	0.92605	3.73	0.10856	3.04	0.81	0.06187	2.17	664	20	666	25	670	15	1
Z-39	79	140	16	0.57	0.0018	0.82444	4.94	0.09918	4.02	0.81	0.06029	2.87	610	24	611	30	614	18	1
Z-40	60	178	19	0.34	0.0021	0.82405	3.89	0.09920	2.92	0.75	0.06025	2.56	610	18	610	24	613	16	0
Z-41	19	95	11	0.21	0.0032	0.87459	5.18	0.10374	4.08	0.79	0.06114	3.19	636	26	638	33	644	21	1
Z-42	180	326	31	0.56	0.0008	0.83788	2.81	0.10108	2.38	0.85	0.06012	1.50	621	15	618	17	608	9	-2
Z-43	44	138	13	0.32	0.0018	0.83850	4.82	0.10095	3.57	0.74	0.06024	3.24	620	22	618	30	612	20	-1
Z-44	369	312	39	1.19	0.0011	0.83308	2.67	0.09968	2.24	0.84	0.06062	1.45	613	14	615	16	626	9	2
Z-45	236	542	56	0.44	0.0009	0.87582	2.55	0.10566	2.07	0.81	0.06012	1.48	647	13	639	16	608	9	-7

Sample	U-Pb age (Ma)	Sample (present-day ratios)			Sample (initial ratios)			T DM (Ma)
Sample	U-Pb age (Ma)	¹⁷⁶ Hf/ ¹⁷⁷ Hf	± 2SE	¹⁷⁶ Lu/ ¹⁷⁷ Hf	¹⁷⁶ Hf/ ¹⁷⁷ Hf (t)	eHf(t)	± 2SE	T DM (Ma)
MI-BR-68_01(z36)	616	0,281927	0,000018	0,000018	0,281927	-16,62	0,47	1796
MI-BR-68_02(z37)	617	0,282125	0,000021	0,000165	0,282123	-9,66	0,49	1538
MI-BR-68_03(z16)	606	0,282354	0,000014	0,000237	0,282351	-1,83	0,07	1230
MI-BR-68_04(z19)	613	0,282402	0,000013	0,000499	0,282397	-0,06	0,00	1172
MI-BR-68_05(z17)	608	0,282294	0,000014	0,000028	0,282294	-3,82	0,12	1305
MI-BR-68_06(z03)	789	0,282328	0,000014	0,001451	0,282306	0,69	0,01	1307
MI-BR-68_07(z20)	783	0,282338	0,000016	0,001000	0,282323	1,17	0,05	1277
MI-BR-68_08(z14)	795	0,281983	0,000015	0,000702	0,281972	-10,98	0,52	1752
MI-BR-68_09(z12)	738	0,282218	0,000014	0,000977	0,282204	-4,08	0,10	1442
MI-BR-68_10(z15)	599	0,282497	0,000015	0,000411	0,282493	3,02	0,09	1040
MI-BR-68_11(z10)	624	0,282496	0,000014	0,000389	0,282491	3,53	0,11	1042
MI-BR-68_12(z07)	1388	0,282066	0,000014	0,000165	0,282061	5,62	0,09	1617
MI-BR-68_15(z28)	733	0,282558	0,000018	0,000664	0,282548	8,02	0,23	964
MI-BR-68_16(z42)	621	0,282335	0,000015	0,000108	0,282334	-2,10	0,05	1252
MI-BR-68_18(z22)	604	0,282425	0,000017	0,000332	0,282422	0,62	0,02	1136
MI-BR-68_21(z09)	594	0,282105	0,000013	0,000090	0,282103	-10,86	0,37	1562
MI-BR-68_22(z31)	621	0,282146	0,000015	0,000053	0,282146	-8,77	0,30	1504

Sample	Unit	Sm	Nd	Rb*	Sr	¹⁴³ Nd/	abs	¹⁴⁷ Sm/	⁸⁷ Sr/	abs	t	ε	f	¹⁴³ Nd/	ε	T_DM	⁸⁷ Sr/
Sample	Unit	ppm	ppm	ppm	ppm	¹⁴⁴ Nd	st error	¹⁴⁴ Nd	⁸⁶ Sr	st error	(Ma)	0 Ma	(Sm/Nd)	¹⁴⁴ Nd _(t)	(t)	Ga	⁸⁶ Sr/ _(t)
RE-CE-03A	Barreiro LTi	6.2	31.1	9	626	0.511899	0.000005	0.1200	0.707183	0.000006	766	-14.4	-0.38972	0.511296	-6.9	1.76	0.7067
RE-CE-149	Barreiro LTi	4.6	21.5	6	641	0.512056	0.000008	0.1296	0.709232	0.000008	766	-11.4	-0.34095	0.511405	-4.8	1.69	0.7089
RE-BR-68	Barreiro LTi	8.1	39.2	5	427	0.512018	0.000007	0.1257	0.707539	0.000004	766	-12.1	-0.36087	0.511387	-5.1	1.68	0.7072
RE-CE-2A	Barreiro HTi	9.9	46.6	8	507	0.512094	0.000005	0.1286	0.706950	0.000009	766	-10.6	-0.34611	0.511448	-4.0	1.61	0.7065
RE-CE-13B	Barreiro HTi	10.4	48.7	15	573	0.512049	0.000004	0.1288	0.706041	0.000005	766	-11.5	-0.34529	0.511402	-4.9	1.68	0.7052
RE-CE-28C	Barreiro HTi	5.7	24.4	15	556	0.512569	0.000004	0.1406	0.704435	0.000010	766	-1.4	-0.28519	0.511862	4.1	0.97	0.7036
RE-CE-29	Barreiro HTi	9.3	46.7	29	622	0.512088	0.000006	0.1209	0.706583	0.000007	766	-10.7	-0.38529	0.511481	-3.3	1.50	0.7051
RE-CE-30A	Barreiro HTi	8.3	41.7	13	553	0.512048	0.000006	0.1205	0.708587	0.000007	766	-11.5	-0.38746	0.511443	-4.1	1.55	0.7078
RE-CE-30B	Barreiro HTi	10.5	53.5	7	569	0.511861	0.000005	0.1188	0.709596	0.000004	766	-15.2	-0.39591	0.511264	-7.6	1.80	0.7092
RE-CE-70B	Barreiro HTi	10.0	47.9	6	619	0.512091	0.000003	0.1267	0.705819	0.000009	766	-10.7	-0.35601	0.511454	-3.8	1.58	0.7055
RE-CE-27C	Barreiro HTi	14.8	74.3	24	498	0.512070	0.000006	0.1204	0.707729	0.000006	766	-11.1	-0.38794	0.511465	-3.6	1.52	0.7062
RE-CE-13B	Barreiro HTi	10.3	48.6	15	573	0.512040	0.000009	0.1288	0.706054	0.000009	766	-11.7	-0.34542	0.511394	-5.0	1.70	0.7052
RE-CE-19	Barreiro HTi	8.5	39.7	3	657	0.512091	0.000005	0.1291	0.705865	0.000006	766	-10.7	-0.34367	0.511443	-4.1	1.62	0.7057
MI-BE-87B	Andrelândia	8.2	48.6	57	711	0.511970	0.000006	0.1204	0.707192	0.000008	766	-13.0	-0.38794	0.511365	-3.7	1.41	0.7047
MI-BR-39	Andrelândia	3.0	9.6	7	146	0.512692	0.000007	0.1870	0.715332	0.000037	766	1.1	-0.04929	0.511753	2.0	1.69	0.7138
MI-III-18	Juiz de Fora WPB	10.0	48.4	9	639	0.512059	0.000008	0.1245	0.707242	0.000006	766	-11.3	-0.36717	0.511433	-4.2	1.60	0.7068
PA-BE-137A	Juiz de Fora IAT	8.0	38.8	72	464	0.511425	0.000009	0.1254	0.715975	0.000002	2400	-23.7	-0.36247	0.509441	-1.7	2.58	0.7004
MI-BR-19C	Juiz de Fora IAT	6.1	26.5	12	250	0.511734	0.000005	0.1386	0.717248	0.000008	2400	-17.6	-0.29543	0.509542	0.3	2.43	0.7124
MI-VIII-15	Juiz de Fora IAT	4.2	17.2	2	35	0.512047	0.000008	0.1496	0.712324	0.000009	2400	-11.5	-0.23962	0.509681	3.0	2.16	0.7066

Mafic groups		U-Pb age (Ga)	T_DM(Nd) (Ga)	εNd_t	⁸⁷ Sr/ ⁸⁶ Sr(i)	εHf_t and T_DM(Hf)
High TiO₂ Barreiro Suite and few mafic enclaves	Intraplate		1.80 to 1.50	-8 to -3	0.7017 to 0.7092
Low TiO₂ Barreiro suite and enclaves of Juiz de Fora Complex and Andrelândia Group	Intraplate	0.77	1.80 to 1.50	-8 to -3	0.7017 to 0.7092	1.75 to 0.96 Ga, +5.61 to +0.24
Most primitive sample of the Barreiro Suite (RE-BR-28)	Intraplate		0.97	+4	0.7036
Low TiO₂ enclaves of the Andrelândia group and Juiz de Fora Complex	Morb		1.80 to 1.50	-8 to -3	0.7017 to 0.7092
Low TiO₂ enclaves of Juiz de For a complex	IATand CAB	2.2 to 2.07	2.58 to 2.16	+3 to -1.7	0.7004 to 0.7124

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[TFN2] ¹Sample and standard are corrected after Pb and Hg blanks; ²²⁰⁷Pb/²⁰⁶Pb and ²⁰⁶Pb/²³⁸U are corrected after common Pb presence. Common Pb assuming ²⁰⁶Pb/²³⁸U - ²⁰⁷Pb/²³⁵U concordant age; ³ƒ-206 denotes the percentage of ²⁰⁶Pb that is common Pb; ⁴²³⁵U = 1/137.88*Utotal; ⁵Standard GJ-1; ⁶Th/U = ²³²Th/²³⁸U *0.992743; ⁷All errors in the table are calculated 1 sigma (% for isotope ratios, absolute for ages) samples marked in bold letters are discarded.