Geological and isotopic characteristics of granites from the Western Pernambuco-Alagoas Domain: implications for the crustal evolution of the Neoproterozoic Borborema Province

Cruz, Rodrigo Fabiano da; Pimentel, Márcio Martins; Accioly, Ana Cláudia de Aguiar; Rodrigues, Joseneusa Brilhante

doi:10.5327/Z23174889201400040008

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Brazilian Journal of Geology

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Articles • Braz. J. Geol. 44 (4) • Oct-Dec 2014 • https://doi.org/10.5327/Z23174889201400040008 copy

Geological and isotopic characteristics of granites from the Western Pernambuco-Alagoas Domain: implications for the crustal evolution of the Neoproterozoic Borborema Province

Caracterização geológica e isotópica dos granitos do Domínio Pernambuco-Alagoas Oeste: implicações na evolução crustal da Província Borborema

Authorship SCIMAGO INSTITUTIONS RANKINGS

The Western Pernambuco-Alagoas Domain is a complex tectonic domain of the Southern part of the Neoproterozoic Borborema Province. It borders the Northern margin of São Francisco Craton. U-Pb and Sm-Nd data discussed in this work show that, in the Western Pernambuco-Alagoas Domain, large volumes of granitic rocks of various ages related to different tectonic events are recognized. The Cariris Velhos Event is represented by Lobo (974 ± 8 Ma) and Rocinha (956 ± 2 Ma) orthogneisses; whereas Paleoproterozoic and Archean basement rocks are represented by Fulgêncio Orthogneiss (1,996 ± 8 Ma), Riacho Seco Gneissic-migmatitic Complex (1,992 ± 27 Ma), and orthogneisses of Entremontes Complex (2,734 ± 11 Ma). Six groups of granitoids are recognized: Brasiliano granitoids (Ediacaran-Cryogenian), with Meso- to Paleoproterozoic model ages; Cariris Velhos granitoids (Tonian) yielding Mesoproterozoic model ages; Paleoproterozoic granitoids from Pernambuco-Alagoas Domain, with Neoarchean to Paleoproterozoic Nd model ages; Paleoproterozoic granitoids from Riacho Seco Nucleus, represented by Riacho Seco Gneissic-migmatitic Complex, with Archean model ages; Archean granitoids represented by the rocks of Entremontes Complex; and granitoids emplaced in the São Francisco Craton displaying Paleoproterozoic to Archean model ages. Prominent among the new data obtained is the Paleoproterozoic age of Riacho Seco Gneissic-migmatitic Complex, which is formed by Archean basement reworking. The new data reveal the presence of Paleoproterozoic and Archean basement inliers and a large volume of Cariris Velhos granitoids in the Western Pernambuco-Alagoas Domain. The orogen, therefore, involved extensive reworking of older blocks, possibly including parts of São Francisco-Congo Craton.

Neoproterozoic Orogen; U-Pb Geochronology; Sm-Nd Isotopes; Entremontes Complex; Riacho Seco Nucleus; Fulgêncio Orthogneiss

Unit	Point	Coord_X	Coord_Y	Chemistry	Sm-Nd	U-Pb
Brasiliano granites
Ibó Migmatite	RF022	471224	9045282		x
Ibó Migmatite	RF068	463255	9029986		x
Chorrochó Augen-gneiss	RF027	471119	9033550		x
Bendó Orthogneiss	RF415	443316	9082776		x
	RF322	438801	9069760		x
Cariris Velhos granites
Lobo Orthogneiss	RF270	472784	9069820		x	x
Rocinha Orthogneiss	RF010	488055	9048504		x
Rocinha Orthogneiss	RF033	466796	9041103	x	x
Rocinha Orthogneiss	RF311	432497	9072305	x
Rocinha Orthogneiss	RF323	439101	9068004	x	x	x
Rocinha Orthogneiss	RF323B	438698	9068243	x
Rocinha Orthogneiss	RF323C	439368	9067372	x
Rocinha Orthogneiss	RF466	439784	9067173	x
Rocinha Orthogneiss	RF467	440177	9066216	x
Rocinha Orthogneiss	FL180	447512	9077182	x
Rocinha Orthogneiss	FL181	446766	9077557	x
Rocinha Orthogneiss	SF182	447364	9075216	x
Rocinha Orthogneiss	FL185	446365	9073209	x
	Rf03	472752	9056286		x
Paleoproterozoic granites
Fulgêncio Orthogneiss	RF040	450613	9045530	x	x
Fulgêncio Orthogneiss	RF240	417807	9050234	x
Fulgêncio Orthogneiss	RF241	416630	9052437	x
Fulgêncio Orthogneiss	RF242	415278	9052878	x
Fulgêncio Orthogneiss	RF243	415448	9055151	x	x	x
Fulgêncio Orthogneiss	RF244	413205	9057996	x	x
Fulgêncio Orthogneiss	RF267	415503	9068278	x	x
Fulgêncio Orthogneiss	RF287	413833	9067886	x
Fulgêncio Orthogneiss	RF288	415434	9067893	x
Fulgêncio Orthogneiss	RF289	416240	9067910	x
Fulgêncio Orthogneiss	RF292	452458	9065471	x
Fulgêncio Orthogneiss	RF328	415508	9069694	x
Fulgêncio Orthogneiss	RF579	411536	9060713	x
RSGMC*	RF111	434681	9037013		x	x
RSGMC*	RF136	426457	9031204		x
Caraíbas Migmatite	RF128	430882	9042347		x
Caraíbas Migmatite	RF249	424686	9044946		x
SFCG**	RF171	422407	9029967		x
SFCG**	RF261	400890	9026667		x
	RF165	447126	9051506		x
Archean granites
Entremontes Complex	RF179	400755	9090278	x	x	x
Entremontes Complex	RF262	396905	9072702	x
Entremontes Complex	RF403	391342	9084593	x
Entremontes Complex	RF425	400081	9089589	x
Entremontes Complex	RF454	418990	9088526	x
Entremontes Complex	RF503	391666	9089173	x

Entremontes Complex
SAMPLE	RF-425	RF-179	RF-503	RF-454	RF-262	RF-403
Wt %
SiO₂	72.55	71.55	71.78	73.66	73.41	71.49
TiO₂	0.26	0.3	0.41	0.34	0.38	0.49
Al₂O₃	11.43	11.82	11.75	11.37	11.77	11.91
Fe₂O₃	3.25	3.85	4.9	4.25	4	4.58
CaO	0.9	1.2	1.3	1	0.98	1.55
Cr₂O₃	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01
K₂O	6.35	6.13	4.3	4.9	5.31	5.3
MgO	0.09	0.26	0.13	0.26	0.12	0.39
MnO	0.05	0.05	0.08	0.08	0.07	0.08
Na₂O	2.44	2.69	2.96	2.76	2.69	0.33
P₂O₅	0.06	0.1	0.03	0.04	< 0.01	0.06
Sum	< 0.01	< 0.01	0.08	0.1	0.06	0.04
LOI	97.38	97.89	97.71	98.75	98.79	96.21
ppm
Ba	613	742	994	1026	884	883
Be	3.2	3.4	4	0.4	3.2	0.4
Cs	0.18	0.06	0.22	0.34	< 0.05	0.18
Ga	21.4	19.4	23.5	22.1	26.6	21.9
Hf	13.69	13.36	16.01	17.72	17	13.79
Nb	28.7	25.03	24.29	19.46	30.04	31.07
Rb	162	144	137	164	160	162
Sn	8.4	6.3	4.9	6.3	4.1	3.9
Sr	52.9	77.6	95.6	70.3	62.5	77
Ta	2.09	2.87	1.34	1.39	1.02	1.65
Th	33.9	20.5	15.3	19	27.3	15.1
U	1.58	1.95	1.62	1.94	1.69	1.64
W	2.2	0.2	0.9	1.2	< 0.1	< 0.1
Y	71.17	67.82	63.14	84.57	84.23	69.74
Zr	521	597	657	629	547	554
Ag	0.02	0.03	0.08	0.11	0.1	< 0.01
Au	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1
As	< 1	< 1	< 1	< 1	< 1	2
Bi	< 0.02	< 0.02	< 0.02	< 0.02	< 0.02	< 0.02
Cd	0.06	0.02	0.11	0.09	0.09	0.04
Co	1	1.4	1.7	2.7	1.7	3.6
Cu	3.8	3.1	9.1	11.3	3.9	15.4
Hg	< 0.01	< 0.01	< 0.01	0.05	0.01	0.02
Mo	0.45	1.9	2.86	1.34	2.09	2.95
Ni	1.9	1.2	6	2	1	3.7
Pb	2.6	1.8	2.2	5.4	3.7	3.4
Sb	< 0.05	< 0.05	< 0.05	< 0.05	< 0.05	< 0.05
Se	< 1	< 1	2	3	< 1	2
Zn	41	31	53	67	70	43
Ce	224.7	170.4	194.9	224.3	222.5	199.5
Dy	15.27	13.55	13.18	17.84	15.18	13.47
Er	8.02	7.25	7.22	9.25	8.31	8.95
Eu	1.69	1.82	2.4	3.51	1.73	2.68
Gd	15.62	14.25	14.82	24.65	16.59	19.41
Ho	2.89	2.62	2.73	3.17	2.9	2.72
La	119.6	105.6	89	136.2	116.4	102.7
Lu	0.99	0.97	0.96	1.25	< 0.05	1.18
Nd	86.7	74.1	85.3	115.5	95.1	89.9
Pr	24.29	20.55	22.79	29.66	26.38	24.44
Sm	16.3	13.7	16.7	19.6	17.7	14.1
Tb	2.56	2.22	2.19	3.54	2.32	2.64
Tm	1.16	1.14	0.91	1.38	1.02	1.12
Yb	7.2	7.3	6.4	7.5	7.5	7.5

Fulgêncio Orthogneiss
SAMPLE	RF-287	RF-288	RF-289	RF-328	RF-267	RF-292	RF-240	RF-241
Wt %
SiO₂	66.64	68.78	66.51	71.39	70.28	67.44	69.36	65.19
TiO₂	0.49	0.26	0.57	0.4	0.36	0.54	0.79	1.19
Al₂O₃	13.36	14.83	13.45	12.91	13.86	13.63	15.14	14.84
Fe₂O₃	3.55	2.4	4.56	3.03	2.86	3.93	5.14	6.15
CaO	1.74	1.32	1.7	1.3	0.98	1.33	2	3.09
Cr₂O₃	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01
K₂O	5.04	5.88	5.44	5.07	5.96	5.59	5.32	4.12
MgO	0.72	0.58	1	0.69	0.5	0.83	1.18	1.7
MnO	0.04	0.03	0.06	0.03	0.03	0.04	0.06	0.08
Na₂O	3.08	3.45	2.92	2.96	3.14	3.21	3.51	3.36
P₂O₅	0.2	0.09	0.08	< 0.01	0.07	0.14	0.38	0.4
Sum	0.19	0.21	0.12	0.37	0.13	0.25	0.38	0.38
LOI	95.07	97.82	96.41	98.14	98.17	96.93	103.28	100.52
ppm
Ba	436	616	477	557	437	495	709	932
Be	1.5	1.6	2.4	2.3	2	1.4	6.4	3.3
Cs	0.52	0.51	0.69	0.4	0.58	0.83	0.87	1.15
Ga	21	19.1	20.9	17.7	19.7	20.1	23.8	24.9
Hf	9.77	4.04	11.27	8.77	8.54	8.96	18.36	14.8
Nb	20.17	9.31	17.91	9.86	11.94	18.87	28.04	53.26
Rb	250	242	304	217	246	291	305.6	223.1
Sn	2.6	4.3	7.2	1.9	3.4	3.3	1.4	3.3
Sr	117	163	116	132	104	115	152.1	257.1
Ta	1.09	0.45	1.09	0.69	0.86	1.55	0.94	1.37
Th	84.2	38.3	147.1	93.7	134.9	66.1	146.5	49.9
U	3.91	2.25	5.83	3.37	3.83	4.83	4.72	1.19
W	< 0.1	< 0.1	2.6	< 0.1	< 0.1	0.6	1.2	0.1
Y	17.56	15.35	21.66	27.03	12.38	28.23	27.46	29.14
Zr	374	133	432	347	298	355	648.4	552.3
Ag	0.02	0.02	0.05	< 0.01	0.06	0.01	< 0.01	< 0.01
Au	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1
As	< 1	< 1	< 1	< 1	< 1	< 1	2	< 1
Bi	< 0.02	< 0.02	< 0.02	< 0.02	< 0.02	< 0.02	0.02	< 0.02
Cd	0.02	0.02	< 0.01	0.02	0.02	< 0.01	0.02	0.06
Co	6.7	5.3	8.9	13.3	4.9	7	10	13.8
Cu	25.4	23.6	27.7	5	149	16	50	39.4
Hg	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	0.04	< 0.01
Mo	0.58	0.67	2.84	0.8	1.08	0.43	0.98	0.69
Ni	8.7	6.6	13.9	17.1	5.4	10.1	12.8	21.3
Pb	4.8	5.5	2.6	4.6	8.1	3.3	6.7	5
Sb	< 0.05	< 0.05	< 0.05	< 0.05	< 0.05	< 0.05	< 0.05	< 0.05
Se	< 1	< 1	< 1	< 1	< 1	< 1	1	< 1
Zn	54	45	62	41	37	56	73	94
Ce	272.3	121	141.4	224.2	311.6	201.6	434.9	304.7
Dy	5.71	4.17	5.34	5.88	4.52	6.76	6.24	5.73
Er	1.58	1.27	2.18	2.14	1.21	2.74	2.06	2.83
Eu	1.25	1.23	1.38	1.58	1.42	1.26	2.72	2.82
Gd	9.62	8.05	8.31	9.88	9.96	9.77	13.43	11.92
Ho	0.65	0.55	0.82	0.87	0.46	1.07	1.21	1.32
La	168.4	91.6	80.7	178.9	215.2	117.6	215.4	150.9
Lu	0.13	0.08	0.22	0.22	0.12	0.28	0.25	0.15
Nd	107	65.1	68.2	98.8	124.8	83.3	203.3	134.6
Pr	31.61	18.55	18.32	28.85	37.19	24.21	55.2	34.96
Sm	13.5	11.2	10.9	12.1	15	12.5	27.8	19
Tb	1.15	0.93	1.02	1.13	1.02	1.33	1.46	1.41
Tm	0.19	0.15	0.26	0.26	0.13	0.38	0.21	0.22
Yb	1.1	0.9	1.8	1.7	1	2.4	1.4	2.1

Rocinha Orthogneiss
SAMPLE	RF-323	RF-323B	RF-323C	RF-466	RF-467	RF-311	FL-180*	FL-181*	FL-185*	SF-182*	RF-033
Wt %
SiO₂	74.33	70.37	72.94	68.54	71.19	77.38	75.56	75.99	77.47	75.5	72.39
TiO₂	0.3	0.29	0.15	0.29	0.31	0.17	0.14	0.2	0.27	0.13	0.2
Al₂O₃	13.4	13.06	11.82	13.43	13.19	12.15	11.8	11.83	12.5	11.12	11.06
Fe₂O₃	3.13	2.85	2.04	2.83	2.86	1.9	1.61	2.6	2.34	1.97	2.56
CaO	0.78	1.71	0.77	0.74	0.92	0.68	0.95	1.05	1.23	0.66	0.8
Cr₂O₃	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01
K₂O	6.82	6.49	6.33	6.47	6.96	6.63	4.77	4.73	5.3	4.53	5.27
MgO	0.31	0.33	0.17	0.23	0.27	0.13	0.21	0.25	0.3	0.13	0.15
MnO	0.04	0.04	0.03	0.04	0.04	0.01	0.05	0.06	0.04	0.05	0.05
Na₂O	2.86	2.7	2.48	3.05	2.68	2.73	2.63	2.62	2.62	2.58	2.79
P₂O₅	< 0.01	< 0.01	0.12	< 0.01	< 0.01	< 0.01	0.03	0.09	0.08	0.03	0.04
Sum	0.19	0.29	0.41	0.23	0.16	0.23	0.17	0.08	0.23	0.52	0.04
LOI	102.12	98.11	97.25	95.72	98.57	101.98	97.91	99.51	102.39	97.21	95.34
ppm
Ba	453	466	280	443	475	323	315	393	461	188	721
Be	4.6	3.6	3.2	6.3	3.8	3.8	5.3	5.5	3.9	3.8	4.5
Cs	10	9.37	4.88	10.87	6.95	3.66	16.76	17.18	9.06	7.02	4.6
Ga	20.5	20.4	19	22.1	20.4	19.6	21.1	22.2	21.8	23.4	18.6
Hf	9.63	10.04	5.05	10.5	10.27	7.73	14	21.92	21.92	18.66	7.07
Nb	26.91	23.47	18.64	27.63	22.56	21.01	24.35	25.88	22.57	23.7	25.52
Rb	298	286	285	297	285	314	365	339	267	338	227.2
Sn	7.1	9	6.4	11.4	7.8	11.4	7.4	8	4.5	8	4
Sr	50.2	120	59.2	50.9	52.7	79.4	70.5	90	77	35.8	79.9
Ta	4.79	4.13	2.79	4.02	2.86	2.79	4.12	3.66	3.06	3.78	1.67
Th	25	26.8	24.6	27.7	27.8	37.9	17.9	38.1	24.1	26.3	25.2
U	4.31	4.84	3.81	4.31	5.57	6.47	5.16	5.95	3.05	3.92	2.96
W	2.6	4.5	4.2	1.7	4.5	0.4	< 0.1	1.5	1.1	0.2	0.5
Y	54.22	60.06	54.35	71.24	57.22	60.77	46.1	46.34	41.83	68.2	51.03
Zr	338	329	164	367	379	240	95.6	156	190	120	243.3
Ag	< 0.01	< 0.01	0.04	0.02	0.03	0.06	0.16	0.15	0.08	0.12	< 0.01
Au	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1	< 0.1
As	< 1	< 1	< 1	< 1	< 1	< 1	< 1	< 1	1	2	< 1
Bi	0.06	0.08	< 0.02	0.08	0.06	0.04	0.39	0.49	0.12	0.69	0.05
Cd	< 0.01	< 0.01	< 0.01	0.01	< 0.01	0.03	0.03	0.09	0.04	< 0.1	0.03
Co	2.3	2.2	1.2	2.9	2.3	0.8	1.6	2.4	2.7	1.4	1.5
Cu	2	2.5	2.5	16.8	6.9	5.3	6.7	9.2	6.7	5.2	3
Hg	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	0.02	< 0.01	0.02
Mo	0.23	0.25	0.53	2.31	0.98	1.24	0.32	0.69	0.39	0.31	0.65
Ni	1.7	2.1	2.2	5.6	2.1	1.4	2.2	2.9	3	2.2	1.4
Pb	5.9	7	7	7.3	5.7	4.8	2.5	4.3	23.4	5.8	3.3
Sb	< 0.05	< 0.05	< 0.05	0.22	0.07	< 0.05	0.07	0.08	< 0.05	0.07	< 0.05
Se	< 1	< 1	< 1	< 1	< 1	1	< 1	< 1	< 1	1	1
Zn	48	49	23	52	46	30	29	48	41	39	56
Ce	138.8	144.1	134.2	157.8	145.2	133.2	75.8	87.5	116	70.6	152.7
Dy	9.56	10.65	10.05	12.7	10.65	10.79	7.56	7.19	6.67	8.7	9.36
Er	5.52	5.81	5.45	7.32	6.07	6.07	4.11	4.35	3.59	5.11	6.01
Eu	1.3	1.22	0.77	1.38	1.18	0.57	0.68	0.78	1.1	0.68	1.36
Gd	9.73	11.56	10.09	13.63	11.37	10.76	7.89	6.35	8.73	9.38	9.82
Ho	1.97	2	1.86	2.47	2	2.03	1.46	1.47	1.33	1.74	2.08
La	85.7	95.7	85.8	106.1	92	92	43.4	45	63.8	37.8	70.2
Lu	0.88	0.83	0.69	1.03	0.76	0.8	0.64	0.69	0.54	0.75	0.83
Nd	54.7	61.4	56	71.8	62.5	59.1	36.6	34.2	51.9	38.9	63.3
Pr	16.2	17.66	16.33	20.23	17.8	17.17	10.33	9.83	14.32	10.06	16.86
Sm	10.4	11.2	10.5	13.7	11.6	11.4	7.8	6.9	9.3	8.4	11.8
Tb	1.72	1.73	1.6	2.12	1.78	1.76	1.19	1.01	1.22	1.47	1.79
Tm	0.97	0.93	0.81	1.11	0.88	0.88	0.63	0.61	0.5	0.75	0.71
Yb	5.6	5.5	5.2	7.2	5.5	5.8	3.8	4.6	3.3	5	5.1

RF-179	Ratios		Ages (Ma)
Spot n°	%²⁰⁶Pb	²³²Th/²³⁸U	²⁰⁷Pb/²⁰⁶Pb	1s(%)	²⁰⁷Pb/²³⁵U	1s(%)	²⁰⁶Pb/²³⁸U	1s(%)	²⁰⁷Pb/²⁰⁶Pb	1s(Ma)	²⁰⁷Pb/²³⁵U	1s(Ma)	²⁰⁶Pb/²³⁸U	1s(Ma)	Conc (%)
MT65_08_a	0.02	0.14	0.18852	0.7	13.8064	1.3	0.53116	1.0	2729	11	2737	12	2746	23	101
MT65_08_b	0.04	0.18	0.18564	0.7	12.2151	2.3	0.47723	2.2	2704	11	2621	21	2515	45	93
MT65_16_a	0.03	0.15	0.19160	0.7	13.4383	1.4	0.50869	1.2	2756	12	2711	13	2651	26	96
MT65_23	0.00	0.13	0.18717	0.8	13.0380	1.3	0.50522	1.0	2717	13	2682	12	2636	22	97
MT65_37	0.02	0.11	0.19039	0.7	14.9269	2.9	0.56863	2.8	2746	11	2811	27	2902	65	106
MT65_38	0.14	0.12	0.18644	1.0	13.3200	1.4	0.51816	1.0	2711	16	2703	13	2691	22	99
MT65_39	0.03	0.49	0.18257	0.9	10.9878	6.0	0.43649	5.9	2676	14	2522	56	2335	116	87
MT65_47	0.03	0.16	0.18769	0.6	13.1696	1.3	0.50889	1.1	2722	10	2692	12	2652	24	97
MT65_55	0.03	0.13	0.18890	0.8	11.9820	2.2	0.46004	2.1	2733	13	2603	21	2440	42	89

RF-243 Spot n°		Contents (ppm)		Ratios							Ages (Ma)
RF-243 Spot n°	%²⁰⁶Pb	U	Th	²³²Th/²³⁸U	²⁰⁷Pb/²⁰⁶Pb	1s(%)	²⁰⁷Pb/²³⁵U	1s(%)	²⁰⁶Pb/²³⁸U	1s(%)	²⁰⁷Pb/²⁰⁶Pb	1s(Ma)	²⁰⁷Pb/²³⁵U	1s(Ma)	²⁰⁶Pb/²³⁸U	1s(Ma)	Conc (%)
006-Z03	0.00	105	45	0.43	0.12203	0.3	5.8279	0.6	0.34636	0.6	1986	6	1951	6	1917	9	97
010-Z05	0.01	93	35	0.38	0.12471	0.6	5.8422	1.1	0.33976	0.9	2025	10	1953	9	1886	15	93
011-Z06	0.51	259	76	0.29	0.12495	0.6	5.8089	0.8	0.33718	0.5	2028	10	1948	7	1873	9	92
012-Z07	0.00	105	45	0.43	0.12308	0.4	6.3994	0.8	0.37710	0.7	2001	7	2032	7	2063	12	103
013-Z08	0.02	148	32	0.21	0.12269	0.6	6.2300	0.9	0.36827	0.6	1996	11	2009	7	2021	10	101
014-Z09	0.00	93	35	0.38	0.12276	0.4	6.3961	0.7	0.37787	0.5	1997	7	2032	6	2066	9	103
019-Z11	0.00	148	32	0.21	0.12291	0.5	6.0520	0.7	0.35712	0.6	1999	8	1983	6	1968	10	98
020-Z12	0.01	93	35	0.38	0.12242	0.5	5.8440	1.0	0.34623	0.8	1992	8	1953	8	1917	14	96
021-Z13N	0.01	259	76	0.29	0.12252	0.4	6.1428	0.8	0.36362	0.7	1993	7	1996	7	1999	11	100
022-Z13B	0.01	105	45	0.43	0.12163	0.5	5.7957	0.8	0.34558	0.7	1980	10	1946	7	1913	11	97
023-Z14N	0.01	148	32	0.21	0.12256	0.8	6.0070	1.1	0.35549	0.7	1994	14	1977	10	1961	13	98
025-Z15	0.11	259	76	0.29	0.12137	0.5	5.8478	1.0	0.34945	0.9	1976	8	1954	9	1932	15	98
026-Z16B	0.00	105	45	0.43	0.12128	1.2	5.9997	1.4	0.35880	0.8	1975	21	1976	12	1976	13	100
031-Z17	0.00	93	35	0.38	0.12300	0.5	6.1247	0.9	0.36114	0.8	2000	9	1994	8	1988	14	99
032-Z18B	0.28	259	76	0.29	0.12156	0.5	5.4826	0.9	0.32710	0.7	1979	8	1898	8	1824	12	92
033-Z18N	0.01	105	45	0.43	0.11967	0.6	6.0576	1.3	0.36713	1.2	1951	11	1984	11	2016	20	103
035-Z20	0.07	93	35	0.38	0.11963	1.7	5.6153	1.9	0.34042	0.8	1951	30	1918	16	1889	13	97
036-Z21	0.19	259	76	0.29	0.12006	0.4	5.6883	0.9	0.34361	0.8	1957	8	1930	8	1904	13	97
040-Z22N	0.02	148	32	0.21	0.12223	0.7	6.1913	1.2	0.36739	1.0	1989	12	2003	10	2017	17	101
041-Z23B	0.22	93	35	0.38	0.12395	0.9	6.0320	1.5	0.35294	1.2	2014	16	1980	13	1949	21	97
042-Z23N	0.23	259	76	0.29	0.12146	0.5	5.5772	1.0	0.33302	0.8	1978	10	1913	8	1853	13	94
043-Z24	0.01	105	45	0.43	0.12021	0.5	5.9925	1.0	0.36154	0.8	1959	10	1975	8	1989	14	102
045-Z26	0.00	93	35	0.38	0.12319	0.4	6.1753	0.8	0.36356	0.7	2003	7	2001	7	1999	12	100
046-Z27	0.00	259	76	0.29	0.12264	0.3	6.0005	0.7	0.35485	0.6	1995	6	1976	6	1958	9	98
049-Z28B	0.01	105	45	0.43	0.12248	0.3	5.9105	0.7	0.34999	0.6	1993	6	1963	6	1935	10	97
051-Z29B	0.00	93	35	0.38	0.11917	0.4	5.3140	0.8	0.32342	0.7	1944	8	1871	7	1806	10	93
052-Z29N	0.01	259	76	0.29	0.11805	0.4	4.8465	1.2	0.29774	1.2	1927	8	1793	10	1680	17	87
053-Z30B	0.18	105	45	0.43	0.12271	0.5	5.9061	0.9	0.34907	0.7	1996	9	1962	8	1930	12	97
054-Z30N	0.06	148	32	0.21	0.12388	0.8	5.8866	1.1	0.34465	0.7	2013	15	1959	10	1909	12	95
053-Z30B	0.18	259	76	0.29	0.12271	0.5	5.9061	0.9	0.34907	0.7	1996	9	1962	8	1930	12	97
054-Z30N	0.06	105	45	0.43	0.12388	0.5	5.8866	0.9	0.34465	0.7	2013	8	1959	8	1909	12	95
055-Z31	0.00	148	32	0.21	0.12295	0.6	6.0402	0.9	0.35631	0.6	1999	11	1982	8	1965	11	98

RF-111 Spot n°		Contents (ppm)		Ratios							Ages (Ma)
RF-111 Spot n°	%²⁰⁶Pb	U	Th	²³²Th/²³⁸U	²⁰⁷Pb/²⁰⁶Pb	1s(%)	²⁰⁷Pb/²³⁵U	1s(%)	²⁰⁶Pb/²³⁸U	1s(%)	²⁰⁷Pb/²⁰⁶Pb	1s(Ma)	²⁰⁷Pb/²³⁵U	1s(Ma)	²⁰⁶Pb/²³⁸U	1s(Ma)	Conc (%)
004-Z01	0.01	93	35	0.38	0.18568	0.6	13.2410	0.9	0.51721	0.8	2704	9	2697	9	2687	17	99
005-Z02	0.50	259	76	0.29	0.08956	2.1	2.1598	2.4	0.17489	1.1	1416	40	1168	16	1039	10	73
006-Z03	0.73	105	45	0.43	0.16841	0.6	9.2062	1.8	0.39648	1.7	2542	10	2359	17	2153	32	85
007-Z04	0.04	148	32	0.21	0.18232	2.0	7.4191	3.1	0.29513	2.4	2674	32	2163	28	1667	36	62
008-Z05	0.21	93	35	0.38	0.12053	0.4	5.8244	1.0	0.35048	0.9	1964	8	1950	9	1937	15	99
010-Z07	0.17	105	45	0.43	0.10822	0.8	3.1963	1.7	0.21421	1.5	1770	15	1456	13	1251	17	71
013-Z08	0.20	148	32	0.21	0.11741	0.6	4.4552	1.8	0.27522	1.7	1917	10	1723	15	1567	24	82
014-Z09	0.04	93	35	0.38	0.11099	0.5	3.8159	1.2	0.24935	1.1	1816	9	1596	10	1435	14	79
015-Z10	0.00	259	76	0.29	0.12293	0.6	6.4063	1.1	0.37795	0.9	1999	11	2033	9	2067	15	103
016-Z11	0.35	105	45	0.43	0.18141	0.5	10.6838	1.5	0.42714	1.4	2666	8	2496	14	2293	28	86
017-Z12	0.01	148	32	0.21	0.15743	0.7	9.0012	0.9	0.41467	0.6	2428	12	2338	8	2236	11	92
018-Z13N	0.13	93	35	0.38	0.16683	1.4	8.9837	1.9	0.39056	1.3	2526	23	2336	17	2125	24	84
019-Z13B	0.07	259	76	0.29	0.13013	0.7	3.7196	1.3	0.20731	1.1	2100	13	1576	10	1214	12	58
020-Z14	0.20	105	45	0.43	0.17081	0.8	10.7499	2.4	0.45646	2.3	2566	13	2502	22	2424	46	94
026-Z16	0.16	259	76	0.29	0.11277	0.8	4.1028	1.9	0.26386	1.7	1845	14	1655	15	1510	23	82
027-Z17	0.11	105	45	0.43	0.16034	0.9	7.4905	2.9	0.33882	2.8	2459	15	2172	26	1881	45	76
028-Z18	0.00	148	32	0.21	0.16050	1.9	10.4418	2.3	0.47185	1.2	2461	33	2475	21	2492	25	101
030-Z19N	0.01	259	76	0.29	0.18641	1.4	12.6794	1.8	0.49333	1.2	2711	22	2656	17	2585	26	95
029-Z19B	0.06	93	35	0.38	0.12319	1.6	3.3622	3.3	0.19794	2.9	2003	28	1496	25	1164	31	58
034-Z20	0.00	148	32	0.21	0.18511	0.5	12.8634	0.8	0.50398	0.6	2699	9	2670	8	2631	13	97
035-Z21	0.24	93	35	0.38	0.18400	0.7	10.5409	1.7	0.41548	1.6	2689	11	2484	16	2240	30	83

RF-270 Spot n°		Contents (ppm)		Ratios							Ages (Ma)
RF-270 Spot n°	%²⁰⁶Pb	U	Th	²³²Th/²³⁸U	²⁰⁷Pb/²⁰⁶Pb	1s(%)	²⁰⁷Pb/²³⁵U	1s(%)	²⁰⁶Pb/²³⁸U	1s(%)	²⁰⁷Pb/²⁰⁶Pb	1s(Ma)	²⁰⁷Pb/²³⁵U	1s(Ma)	²⁰⁶Pb/²³⁸U	1s(Ma)	Conc (%)
006-Z03	0.02	105	45	0.43	0.07181	0.6	1.5913	1.2	0.16072	1.1	980	12	967	8	961	10	98
008-Z05	0.01	93	35	0.38	0.07159	0.5	1.5560	1.2	0.15764	1.1	974	10	953	7	944	9	97
009-Z06	0.04	259	76	0.29	0.07099	0.6	1.4723	1.1	0.15043	0.9	957	13	919	7	903	8	94
014-Z09	0.02	93	35	0.38	0.07277	0.7	1.6189	1.2	0.16136	1.0	1007	15	978	8	964	9	96
015-Z10	0.01	259	76	0.29	0.07158	0.7	1.6306	1.1	0.16521	0.9	974	14	982	7	986	8	101
018-Z12B	0.02	93	35	0.38	0.07160	1.2	1.5543	2.0	0.15744	1.6	975	24	952	12	943	14	97
020-Z14	0.01	105	45	0.43	0.07157	0.5	1.5999	0.9	0.16212	0.8	974	11	970	6	969	7	99
023-Z15	0.02	148	32	0.21	0.07258	1.0	1.5905	1.3	0.15893	0.7	1002	21	966	8	951	6	95
018-Z12B	0.02	93	35	0.38	0.07160	1.2	1.5543	2.0	0.15744	1.6	975	24	952	12	943	14	97
020-Z14	0.01	105	45	0.43	0.07157	0.5	1.5999	0.9	0.16212	0.8	974	11	970	6	969	7	99
023-Z15	0.02	148	32	0.21	0.07258	1.0	1.5905	1.3	0.15893	0.7	1002	21	966	8	951	6	95
028-Z20	0.02	93	35	0.38	0.07054	0.6	1.5524	1.3	0.15961	1.2	944	13	951	8	955	10	101
029-Z21	0.05	259	76	0.29	0.07088	0.8	1.4404	1.2	0.14739	0.9	954	17	906	7	886	8	93
030-Z22	0.01	105	45	0.43	0.07144	0.5	1.6575	1.4	0.16828	1.4	970	9	992	9	1003	13	103
037-Z26	0.04	148	32	0.21	0.07124	1.4	1.5375	1.7	0.15652	1.0	964	28	945	10	937	9	97
039-Z28	0.04	259	76	0.29	0.07263	1.6	1.6390	2.0	0.16367	1.0	1004	33	985	12	977	9	97
043-Z30	0.03	148	32	0.21	0.07056	1.3	1.4873	1.8	0.15288	1.3	945	26	925	11	917	11	97
044-Z31	0.03	93	35	0.38	0.07177	0.9	1.5968	1.4	0.16137	1.0	979	18	969	9	964	9	98
052-Z36	0.01	105	45	0.43	0.07218	0.6	1.6347	1.2	0.16425	1.1	991	11	984	8	980	10	99
054-Z38	0.04	93	35	0.38	0.07195	1.2	1.4771	1.8	0.14889	1.4	985	24	921	11	895	12	91
055-Z39	0.03	259	76	0.29	0.07258	1.0	1.4555	1.7	0.14545	1.4	1002	21	912	10	875	11	87
057-Z41	0.01	148	32	0.21	0.07079	0.9	1.7350	1.9	0.17776	1.7	951	19	1022	13	1055	17	111
059-Z43	0.03	259	76	0.29	0.07269	1.2	1.5900	2.1	0.15864	1.7	1005	25	966	13	949	15	94
064-Z45n	0.02	148	32	0.21	0.07231	1.5	1.5505	1.8	0.15552	0.9	995	30	951	11	932	8	94
084-Z61	0.02	93	35	0.38	0.07160	0.9	1.7065	1.7	0.17286	1.5	975	19	1011	11	1028	14	105

RF-323 Spot n°		Ratios						Ages (Ma)
RF-323 Spot n°	%²⁰⁶Pb	²³²Th/²³⁸U	²⁰⁷Pb/²⁰⁶Pb	1s(%)	²⁰⁷Pb/²³⁵U	1s(%)	²⁰⁶Pb/²³⁸U	1s (%)	²⁰⁷Pb/²⁰⁶Pb	1s(Ma)	²⁰⁷Pb/²³⁵U	1s(Ma)	²⁰⁶Pb/²³⁸U	1s(Ma)	Conc (%)
MT32_01	0.06	0.21	0.07109	0.7	1.54777	1.2	0.15791	0.9	960	15	950	7	945	8	98
MT32_08	0.04	0.16	0.07113	0.7	1.60268	1.4	0.16343	1.2	961	14	971	9	976	11	102
MT32_10	0.06	0.21	0.07004	0.7	1.55387	1.3	0.16089	1.0	930	15	952	8	962	9	103
MT32_20	0.04	0.23	0.07059	0.6	1.56495	1.2	0.16078	1.1	946	11	956	8	961	10	102
MT32_21	0.03	0.27	0.07073	0.5	1.53479	1.0	0.15738	0.8	950	11	944	6	942	7	99
MT32_23	0.06	0.21	0.07124	0.7	1.58430	1.4	0.16130	1.3	964	14	964	9	964	11	100
MT32_27	0.02	0.24	0.07061	0.6	1.53077	1.0	0.15724	0.8	946	12	943	6	941	7	100
MT32_29	0.08	0.21	0.07029	0.8	1.57387	1.4	0.16239	1.1	937	16	960	8	970	10	104
MT32_31	0.09	0.26	0.07011	0.8	1.56719	1.1	0.16213	0.8	932	16	957	7	969	8	104
MT32_38	0.06	0.17	0.07107	0.9	1.57600	1.3	0.16084	0.9	959	19	961	8	961	8	100
MT32_39	0.05	0.27	0.07137	0.6	1.58020	1.4	0.16058	1.3	968	12	962	9	960	11	99
MT32_38	0.00	0.16	0.07172	1.1	1.58902	1.4	0.16070	0.9	978	22	966	9	961	8	98
MT32_43	0.09	0.19	0.07026	0.8	1.57160	1.2	0.16223	0.9	936	16	959	8	969	8	104
MT32_46	0.21	0.22	0.07053	1.0	1.55485	1.7	0.15988	1.4	944	20	952	10	956	12	101

Sample	Sm(ppm)	Nd(ppm)	¹⁴⁷Sm/¹⁴⁴Nd	¹⁴³Nd/¹⁴⁴Nd ± 2SE	e_Nd(0)	e_Nd(600 Ma)	(Ga)
RF 022	4.429	23.747	0.1127	0.512091 ± 13	-10.68	-4.23	1.43
RF 027	10.143	60.474	0.1014	0.51212 ± 32	-10.11	-2.80	1.25
RF 068	0.619	2.731	0.1371	0.512092 ± 9	-10.66	-6.09	1.88
RF 322	15.443	74.099	0.1260	0.5121470 ± 25	-9.58	-4.16	1.54
RF 415	4.551	25.801	0.1066	0.5117733 ± 13	-16.87	-9.97	1.79
						e_Nd(1 Ga)
RF 003	6.466	36.024	0.1085	0.512092 ± 17	-10.64	0.64	1.37
RF 010	10.845	50.698	0.1293	0.512228 ± 13	-8.00	0.63	1.46
RF 033	12.198	62.360	0.1182	0.512057 ± 13	-11.33	-1.29	1.56
RF 270	5.278	27.755	0.1150	0.512039 ± 11	-11.68	-1.23	1.54
RF 323	12.094	64.891	0.1127	0.5120705 ± 15	-11.07	-0.32	1.45
						e_Nd(2 Ga)
RF 040	11.781	75.738	0.0940	0.510939 ± 13	-33.14	-6.18	2.68
RF 111	5.326	33.181	0.0970	0.510647 ± 13	-38.83	-13.30	3.14
RF 128	1.865	14.620	0.0771	0.510574 ± 15	-40.27	-9.59	2.75
RF 136	9.559	62.650	0.0922	0.510547 ± 9	-40.79	-14.02	3.14
RF 165	13.048	89.247	0.0884	0.510897 ± 17	-33.97	-6.18	2.6
RF 171	3.589	22.049	0.0984	0.511001 ± 19	-31.94	-6.72	2.7
RF 243	8.227	58.814	0.0846	0.510879 ± 3	-34.31	-5.55	2.55
RF 244	24.318	185.700	0.0792	0.510578 ± 2	-40.18	-10.06	2.79
RF 249	4.173	17.774	0.1419	0.511816 ± 10	-16.03	-1.97	2.61
RF 267	23.038	202.566	0.0687	0.510671 ± 3	-38.37	-5.52	2.49
						e_Nd(2.7 Ga)
RF 179	14.362	83.267	0.1043	0.5107796 ± 16		-3.76	3.17
RF 261	24	103.108	0.1313	0.511132 ± 9	-29.38	-6.70	3.59

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E-mail: sbgeol@uol.com.br

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[1] *Corresponding author