Isotopic study of the Pb-Zn (Cu-Ag) Santa Maria Deposit, Caçapava do Sul Region, Rio Grande do Sul, Brazil

Pereira, David Ramos; Macambira, Moacir José Buenano; Pires, Karen Cristina de Jesus; Lago, Samuel Bouças do

doi:10.1590/2317-4889202120200091

David Ramos Pereira ^**Corresponding author.

Universidade Federal do Pará - Belém (PA), Brazil. E-mails: david.pereira@ig.ufpa.br, moamac@ufpa.br

http://orcid.org/0000-0002-2387-4291

Moacir José Buenano Macambira

Universidade Federal do Pará - Belém (PA), Brazil. E-mails: david.pereira@ig.ufpa.br, moamac@ufpa.br

http://orcid.org/0000-0003-1576-4663

Karen Cristina de Jesus Pires

Regulatory Policy Management, National Mining Agency - Porto Alegre (RS), Brazil. E-mail: karen.pires@anm.gov.br

http://orcid.org/0000-0003-0343-9898

Samuel Bouças do Lago

Nexa Resources - Caçapava do Sul (RS), Brazil. E-mail: samuel.lago@nexaresources.com

http://orcid.org/0000-0003-3699-6551

*Corresponding author.

S.L. contributed during the field activities, facilitating the acquisition of the samples and geological data. K.P. helped in the selection of the drill cores, petrographic descriptions and metallogenetic part of the research. M.M. contributed to the conception of the research and elaboration of the manuscript, mainly in relation to geochronology and Pb isotopic geology. The author D.P. was responsible for the macroscopic and petrographic description of the samples, carrying out the isotopic analyses, data treatment, and preparation of the manuscript, including figures.

Competing interests: The authors declare no competing interests.

Zircon	ƒ₂₀₆ ^a	Pb ppm	Th ppm	U ppm	Th/U^b	Isotopic Ratios^c							Ages (Ma)
Zircon	ƒ₂₀₆ ^a	Pb ppm	Th ppm	U ppm	Th/U^b	207Pb/ 235U	1 s [%]	206Pb/ 238U	1 s [%]	Rho^d	207Pb/ 206Pb^e	1 s [%]	206Pb/ 238U	1 s abs	207Pb/ 235U	1 s abs	207Pb/ 206Pb	1 s abs	% Conc^f
From trachyte
DMK-CL B1-1	0.0005	14.8	216.1	162.4	1.34	0.7253	5.01	0.0902	3.59	0.72	0.0583	3.50	557	20	554	28	541	19	103
DMK-CL B2-2	0.0047	4.2	21.3	33.4	0.64	0.7446	3.45	0.0911	2.05	0.60	0.0593	2.77	562	12	565	19	576	16	98
DMK-CL B3	0.0056	4.6	38.1	36.2	1.06	0.7499	4.39	0.0921	2.30	0.52	0.0591	3.74	568	13	568	25	570	21	100
DMK-CL B4	0.0031	1.8	9.2	9.7	0.95	0.7034	5.83	0.0873	3.54	0.61	0.0584	4.63	540	19	541	32	545	25	99
DMK-CL C2-1	0.0064	15.2	76.8	105.7	0.73	0.7723	5.70	0.0942	4.44	0.78	0.0594	3.57	581	26	581	33	583	21	100
DMK-CL C2-2	0.0025	2.5	11.2	17.6	0.64	0.7456	4.91	0.0913	2.96	0.60	0.0592	3.92	563	17	566	28	576	23	98
DMK-CL C3-1	0.0063	18.2	59.8	151.3	0.40	0.7555	4.87	0.0926	3.63	0.75	0.0592	3.25	571	21	571	28	573	19	100
DMK-CL C3-2	0.0044	4.3	24.5	30.6	0.80	0.7627	3.43	0.0934	2.36	0.69	0.0592	2.49	575	14	576	20	576	14	100
DMK-CL D1-2	0.0064	2.2	14.4	16.2	0.90	0.7303	6.19	0.0906	4.04	0.65	0.0585	4.69	559	23	557	34	547	26	102
Inherited from basement or country rocks
DMK-CL A1-1	0.0034	28.8	186.8	563.6	0.33	0.8574	3.79	0.1010	2.21	0.58	0.0616	3.08	620	14	629	24	659	20	94
DMK-CL A1-2	0.0041	2.4	11.6	18.2	0.64	0.9343	5.04	0.1120	2.04	0.41	0.0605	4.61	684	14	670	34	621	29	110
DMK-CL A4	0.0024	4.4	21.7	29.3	0.75	0.9574	4.50	0.1096	2.72	0.60	0.0634	3.59	670	18	682	31	720	26	93
DMK-CL A6 (1)	0.0080	7.7	2.1	36.0	0.06	2.0525	4.94	0.1952	3.12	0.63	0.0763	3.83	1149	36	1133	56	1102	42	104
DMK-CL A6 (2)	0.0026	25.2	21.6	67.6	0.32	6.4671	2.75	0.3777	1.81	0.66	0.1242	2.06	2066	37	2041	56	2017	42	102
DMK-CL B5	0.0023	9.4	9.2	20.4	0.45	6.3058	1.55	0.3672	0.99	0.64	0.1245	1.20	2016	20	2019	31	2022	24	100
DMK-CL C1	0.0021	4.1	15.4	28.3	0.55	0.8926	6.03	0.1072	4.36	0.72	0.0604	4.16	657	29	648	39	617	26	106
DMK-CL C5	0.0025	2.8	24.0	15.3	1.58	1.1302	5.23	0.1248	3.74	0.71	0.0657	3.66	758	28	768	40	796	29	95
DMK-CL D1-1	0.0053	73.6	48.2	110.4	0.44	8.9645	2.03	0.4415	1.06	0.52	0.1473	1.73	2357	25	2334	47	2314	40	102
DMK-CL D2-2	0.0047	2.4	10.3	15.9	0.65	1.2690	4.76	0.1389	3.25	0.68	0.0663	3.49	838	27	832	40	815	28	103
DMK-CL E1	0.0062	15.6	37.8	134.2	0.28	0.8481	4.11	0.1010	2.43	0.59	0.0609	3.31	620	15	624	26	637	21	97
DMK-CL F1	0.0036	6.8	4.9	69.0	0.07	1.1415	4.76	0.1271	2.63	0.55	0.0651	3.97	771	20	773	37	779	31	99
Discordant
DMK-CL A2-1	0.0005	38.6	47.9	115.8	0.42	4.5666	1.86	0.2781	0.75	0.40	0.1191	1.70	1582	12	1743	32	1943	33	81
DMK-CL A2-2	0.0044	3.7	19.1	24.9	0.77	0.9135	5.03	0.1340	1.81	0.36	0.0494	4.69	811	15	659	33	168	8	481
DMK-CL A3	0.0020	7.1	11.6	22.0	0.53	4.6151	3.35	0.2821	2.13	0.64	0.1186	2.59	1602	34	1752	59	1936	50	83
DMK-CL B1-2	0.0013	4.4	17.1	30.1	0.57	0.8234	4.56	0.1059	2.80	0.61	0.0564	3.61	649	18	610	28	469	17	138
DMK-CL B2-1	0.0056	35.8	9.3	88.6	0.11	10.7623	3.85	0.3997	3.56	0.92	0.1953	1.48	2168	77	2503	96	2787	41	78
DMK-CL D2-1	0.0067	19.4	13.9	126.5	0.11	1.0634	3.72	0.1266	2.01	0.54	0.0609	3.13	769	15	736	27	636	20	121
DMK-CL D3	0.0067	18.4	26.3	38.4	0.69	6.3212	2.42	0.3444	2.19	0.90	0.1331	1.03	1908	42	2021	49	2139	22	89

Locality	Rock	Age (Ma)	Method	Reference
Camaquã Basin	Rhyolite	545 ± 13	Rb-Sr	*Almeida et al. (1996*Almeida D.P.M., Zerfass H., Basei M.A. 1996. Mineralogia, geoquímica e novas idades para o vulcanismo ácido da Bacia do Camaquã. In: Congresso Brasileiro de Geologia, 39., 1996, Salvador. Annals…, v. 2, p. 19-21.)
Perau Hill	Rhyolite	573 ± 18	U-Pb SHRIMP	Chemale Jr. (2000Chemale Jr. F. 2000. Evolução geológica do Escudo Sul-rio-grandense. In: Holz M., De Ros L.F. (Eds.). Geologia do Rio Grande do Sul. Porto Alegre: CIGO/UFRGS, p. 13-52.)
Martins Hill	Qtz-diorite	550 ± 5	Pb-Pb evaporation	*Toniolo et al. (2004*Toniolo J.A., Remus M.V.D., Macambira M.J.B., Moura C.A.V. 2004. Metalogênese do Depósito de Cobre Cerro dos Martins, RS, Revisão e Geoquímica Isotópica de Sr, S, O e C. Pesquisas em Geociências, 31(2):41-67. https://doi.org/10.22456/1807-9806.19573 https://doi.org/https://doi.org/10.22456... )
Ramada Plateau	Subvolcanic rhyolite	549 ± 5	U-Pb SHRIMP	*Sommer et al. (2005*Sommer C.A., Lima E.F., Nardi L.V.S., Figueiredo A.M.G., Pierosan R. 2005. Potassic and low- and high-Ti mildly alkaline volcanism in the Neoproterozoic Ramada Plateau, southernmost Brazil. Journal of South American Earth Sciences, 18(3-4):237-254. https://doi.org/10.1016/j.jsames.2004.11.003 https://doi.org/https://doi.org/10.1016/... )
Ramada Plateau	Rhyolite	574 ± 7	U-Pb TIMS	*Janikian et al. (2008*Janikian L., Almeida R.P., Trindade D., Ferreira R.I., Fragoso-Cesar A.R.S., D'Agrella-Filho M.S., Dantas E.L., Tohver E. 2008. The continental record of Ediacaran volcano-sedimentary successions in southern Brazil and their global implications. Terra Nova, 20(4):259-266. https://doi.org/10.1111/j.1365-3121.2008.00814.x https://doi.org/https://doi.org/10.1111/... )
Bugio Hill	Basalt	553 ± 5	U-Pb LA-ICP-MS	*Almeida et al. (2012*Almeida D.P.M., Chemale Jr. F., Machado A. 2012. Late to Post-Orogenic Brasiliano-Pan-African Volcano-Sedimentary Basins in the Dom Feliciano Belt, Southernmost Brazil. In: Al-Juboury A.I. (Ed.). Petrology: New Perspectives and Applications. Rijeka: InTech, v. 1, p. 73-130. https://doi.org/10.5772/25189 https://doi.org/https://doi.org/10.5772/... )
Taquarembó Plateau	Acid tuff	553 ± 17	U-Pb LA-ICP-MS	*Janikian et al. (2012*Janikian L., Almeida R.P., Fragoso-Cesar A.R.S., Souza Martins V.T., Dantas E.L., Tohver E., McReath I., D'Agrella-Filho M.S. 2012. Ages (U-Pb SHRIMP and LA ICPMS) and stratigraphic evolution of the Neoproterozoic volcano-sedimentary successions from the extensional Camaquã Basin, Southern Brazil. Gondwana Research, 21(2-3):466-482. https://doi.org/10.1016/j.gr.2011.04.010 https://doi.org/https://doi.org/10.1016/... )
Bom Jardim	Subvolcanic rhyolite	572 ± 7	U-Pb LA-ICP-MS	*Janikian et al. (2012*Janikian L., Almeida R.P., Fragoso-Cesar A.R.S., Souza Martins V.T., Dantas E.L., Tohver E., McReath I., D'Agrella-Filho M.S. 2012. Ages (U-Pb SHRIMP and LA ICPMS) and stratigraphic evolution of the Neoproterozoic volcano-sedimentary successions from the extensional Camaquã Basin, Southern Brazil. Gondwana Research, 21(2-3):466-482. https://doi.org/10.1016/j.gr.2011.04.010 https://doi.org/https://doi.org/10.1016/... )
Ramada Plateau	Subvolcanic rhyolite	562 ± 2	U-Pb LA-ICP-MS	*Matté et al. (2016*Matté V., Sommer C.A., de Lima E.F., Philipp R.P., Basei M.A.S. 2016. Post-collisional Ediacaran volcanism in oriental Ramada Plateau, southern Brazil. Journal of South American Earth Sciences, 71:201-222. https://doi.org/10.1016/j.jsames.2016.07.015 https://doi.org/https://doi.org/10.1016/... )
Ramada Plateau	Rhyolitic ignimbrite	560 ± 2	U-Pb LA-ICP-MS	*Matté et al. (2016*Matté V., Sommer C.A., de Lima E.F., Philipp R.P., Basei M.A.S. 2016. Post-collisional Ediacaran volcanism in oriental Ramada Plateau, southern Brazil. Journal of South American Earth Sciences, 71:201-222. https://doi.org/10.1016/j.jsames.2016.07.015 https://doi.org/https://doi.org/10.1016/... )
Ramada Plateau	Rhyolitic ignimbrite	561 ± 2	U-Pb LA-ICP-MS	*Matté et al. (2016*Matté V., Sommer C.A., de Lima E.F., Philipp R.P., Basei M.A.S. 2016. Post-collisional Ediacaran volcanism in oriental Ramada Plateau, southern Brazil. Journal of South American Earth Sciences, 71:201-222. https://doi.org/10.1016/j.jsames.2016.07.015 https://doi.org/https://doi.org/10.1016/... )
Ramada Plateau	Subvolcanic trachyte	560 ± 14	U-Pb LA-ICP-MS	*Matté et al. (2016*Matté V., Sommer C.A., de Lima E.F., Philipp R.P., Basei M.A.S. 2016. Post-collisional Ediacaran volcanism in oriental Ramada Plateau, southern Brazil. Journal of South American Earth Sciences, 71:201-222. https://doi.org/10.1016/j.jsames.2016.07.015 https://doi.org/https://doi.org/10.1016/... )
Tupanci Hill	Rhyolite	579 ± 6	U-Pb LA-ICP-MS	*Sommer et al. (2017*Sommer C.A., Leitzke F.P., Lima E.F.D., Barreto C.J.S., Lafon J.M., Matté V., Philipp R.P., Conceição R.V., Basei M.Â.S. 2017. Zircon U-Pb geochronology, Sm-Nd and Pb-Pb isotope systematics of Ediacaran post-collisional high-silica Acampamento Velho volcanism at the Tupanci area, NW of the Sul-Rio-Grandense Shield, Brazil. Brazilian Journal of Geology, 47(4):545-560. https://doi.org/10.1590/2317-4889201720170064 https://doi.org/https://doi.org/10.1590/... )
Picados Hill	Rhyolite	558 ± 39	U-Pb LA-ICP-MS	*Sommer et al. (2017*Sommer C.A., Leitzke F.P., Lima E.F.D., Barreto C.J.S., Lafon J.M., Matté V., Philipp R.P., Conceição R.V., Basei M.Â.S. 2017. Zircon U-Pb geochronology, Sm-Nd and Pb-Pb isotope systematics of Ediacaran post-collisional high-silica Acampamento Velho volcanism at the Tupanci area, NW of the Sul-Rio-Grandense Shield, Brazil. Brazilian Journal of Geology, 47(4):545-560. https://doi.org/10.1590/2317-4889201720170064 https://doi.org/https://doi.org/10.1590/... )
Palma	Basalt	572 ± 6	U-Pb LA-ICP-MS	*Vedana et al. (2017*Vedana L.A., Philipp R.P., Sommer C.A. 2017. Post-collisional basalts of the Acampamento Velho Formation, Camaquã Basin, São Gabriel Terrane, southernmost Brazil. Brazilian Journal of Geology, 47(3):467-489. https://doi.org/10.1590/2317-4889201720170019 https://doi.org/https://doi.org/10.1590/... )
Palma	Andesitic basalt	563 ± 2	U-Pb LA-ICP-MS	*Vedana et al. (2017*Vedana L.A., Philipp R.P., Sommer C.A. 2017. Post-collisional basalts of the Acampamento Velho Formation, Camaquã Basin, São Gabriel Terrane, southernmost Brazil. Brazilian Journal of Geology, 47(3):467-489. https://doi.org/10.1590/2317-4889201720170019 https://doi.org/https://doi.org/10.1590/... )
Camaquã Mines	Trachyte	565 ± 5	U-Pb LA-ICP-MS	This work

Sample	Mineral	²⁰⁶ Pb/ ²⁰⁴ Pb	2s	²⁰⁷ Pb/ ²⁰⁴ Pb	2s	²⁰⁸ Pb/ ²⁰⁴ Pb	2s
A1-10	GALENA	16.950	0.001	15.502	0.001	37.619	0.002
A2-5	GALENA	16.905	0.002	15.487	0.002	37.577	0.004
A3-5	GALENA	16.983	0.001	15.499	0.001	37.591	0.002
A3-7 L1	SPHALERITE	16.965	0.002	15.521	0.002	37.659	0.005
A3-7 L2	SPHALERITE	16.963	0.004	15.511	0.004	37.632	0.010
A3-7 L3	SPHALERITE	16.947	0.002	15.499	0.002	37.601	0.005
A3-7 L4	SPHALERITE	16.973	0.003	15.528	0.003	37.688	0.007
A3-7 L5	SPHALERITE	16.956	0.001	15.497	0.001	37.598	0.003
A3-7 L6	SPHALERITE	17.595	0.002	15.552	0.002	37.627	0.004
A3-8 L1	SPHALERITE	16.945	0.002	15.507	0.002	37.628	0.005
A3-8 L2	SPHALERITE	16.947	0.002	15.496	0.002	37.581	0.004
A3-8 L3	SPHALERITE	16.945	0.001	15.493	0.001	37.572	0.002
A3-8 L4	SPHALERITE	16.960	0.001	15.517	0.001	37.652	0.002
A3-8 L5	SPHALERITE	16.963	0.001	15.495	0.001	37.582	0.002
A3-8 L6	SPHALERITE	17.555	0.011	15.574	0.010	37.737	0.025
Data from *Remus et al. (2000*Remus M.V.D., Hartmann L.A., McNaughton N.J., Groves D.I., Reischl J.L. 2000. A distal magmatic-hydrotermal origin for the Camaquã Cu (Au-Ag) and Santa Maria Pb-Zn (Cu-Ag) deposits, southern Brazil. Gondwana Research, 3(2):155-174. https://doi.org/10.1016/S1342-937X(05)70094-0 https://doi.org/https://doi.org/10.1016/... )
MSMA-G	GALENA	16.927	-	15.488	-	37.559	-
MSMC-G	GALENA	16.950	-	15.502	-	37.625	-
MSB-B gn	GALENA	16.960	-	15.494	-	37.550	-
MSMC-S	SPHALERITE	16.939	-	15.491	-	37.576	-
CB-199E.P20	CHALCOPYRITE I	19.468	-	15.671	-	40.320	-
CB-199E.P20	PYRITE	19.185	-	15.643	-	39.476	-
CB.P-19	PYRITE	18.626	-	15.605	-	38.933	-
CB.P-19	CHALCOPYRITE	18.616	-	15.621	-	39.064	-
CB-282A	CHALCOPYRITE	18.024	-	15.573	-	38.208	-
TV-211	PIR/CALCOP II	19.672	-	15.674	-	39.438	-

[1] *Corresponding author.

Brasil

Brasil

Isotopic study of the Pb-Zn (Cu-Ag) Santa Maria Deposit, Caçapava do Sul Region, Rio Grande do Sul, Brazil

ABSTRACT