Neoarchean to Rhyacian crustal records along the Middle Xingu River area, Amazonian craton

Macambira, Moacir José Buenano; Vasquez, Marcelo Lacerda; Monteiro, Pablo Conduru; Armstrong, Richard Austin

doi:10.1590/2317-4889202220220017

Acessibilidade / Reportar erro

Brasil

Brazilian Journal of Geology

Español English

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

Article • Braz. J. Geol. 52 (4) • 2022 • https://doi.org/10.1590/2317-4889202220220017 copy

Neoarchean to Rhyacian crustal records along the Middle Xingu River area, Amazonian craton

Authorship SCIMAGO INSTITUTIONS RANKINGS

Abstract

The Carajás (3.0–2.5 Ga) and Xingu-Iricoumé (1.99–1.86 Ga) blocks comprise the Central Amazonia Province (CAP) that is in contact with the Maroni-Itacaiúnas Province (MIP) within the Amazonian craton. The CAP is the oldest portion (Nd-T_DM) of the craton and corresponds to an Archean nucleus bordered by younger Paleo-Mesoproterozoic mobile belts, including the MIP. Because the location and tectonic boundaries between these provinces are insufficiently known, we carried out a geological survey along the Middle Xingu River, cutting the WNW-ESE regional trend, to further understand cratonic evolution of the MIP and its southeastern boundary in this key area. Geochronologic results (Pb-evaporation and U-Pb SHRIMP in zircon and monazite), supported by petrographic and field observations, allowed identification of the following lithotypes and their ages: migmatitic gneisses (2859–2080 Ma), tonalitic gneisses (2554 ± 3 Ma, 2480 ± 9 Ma), enderbites (2114 ± 3 Ma), charnockites (2094 ± 4 Ma, 2084 ± 2 Ma), granodiorites (2079 ± 3 Ma), leucogranitic vein (2075 ± 2 Ma), and pelitic paragneisses (2062 ± 8 Ma). These ages are related to the reworking of Archean crust during Rhyacian magmatic arc amalgamation (2.22–2.13 Ga) and collision in the Transamazonian cycle (ca. 2.1 Ga).

Keywords:
Transamazonian cycle; Maroni-Itacaiúnas Province; Amazonian craton; Zircon and monazite geochronology

Grain number	T (°C)	#ratios	²⁰⁴Pb/²⁰⁶Pb	2σ	²⁰⁸Pb/²⁰⁶Pb	2σ	²⁰⁷Pb/²⁰⁶Pb	2σ	(²⁰⁷Pb/²⁰⁶Pb)c	2σ	(²⁰⁷Pb/²⁰⁶Pb) age (Ma)	2σ
PMM-09C – Enderbite
01	1,450	34	0.000175	5	0.06700	52	0.13190	59	0.12940	51	2090	7
	1,500	36	0.000082	6	0.07679	120	0.13174	21	0.13062	29	2107	4
	1,550	38	0.000125	3	0.12111	49	0.13296	18	0.13129	23	2116	3
02	1,450	36	0.000187	14	0.04132	37	0.13050	18	0.12807	32	2072	4
	1,500	32	0.000116	2	0.04884	22	0.13274	38	0.13118	43	2114	6
	1,550	34	0.000133	11	0.05873	44	0.13347	25	0.13164	26	2120	3
05	1,450	34	0.000229	23	0.06648	164	0.13093	49	0.12798	33	2071	5
05	1,500	34	0.000057	2	0.09307	22	0.13171	16	0.13097	17	2111	2
07	1,450	8	0.001704	448	0.05930	1566	0.13089	85	0.10771	632	1761	107
07	1,500	20	0.000136	6	0.09562	56	0.13281	21	0.13117	22	2114	3
Mean (²⁰⁷Pb/²⁰⁶Pb) age (158 isotopic ratios) 2114 ± 3 Ma/USD = 2.24
PMM-23A – Leucossomatic vein
01	1,500	40	0.000006	7	0.04573	28	0.12892	31	0.12889	31	2083	4
02	1,500	34	0.000006	2	0.03849	18	0.12842	19	0.12837	18	2076	3
02	1,550	38	0.000016	4	0.03880	32	0.12830	49	0.12791	42	2070	6
03	1,500	36	0.000007	2	0.03604	12	0.12834	18	0.12825	18	2075	2
03	1,550	8	0.000017	4	0.03609	50	0.12864	82	0.12842	82	2077	11
04	1,500	34	0.000025	4	0.03772	17	0.12847	29	0.12814	30	2073	4
05	1,500	28	0.000006	3	0.03879	17	0.12839	24	0.12833	25	2076	4
06	1,500	30	0.000015	5	0.03882	15	0.12825	68	0.12807	66	2072	9
07	1,500	38	0.000043	19	0.03802	62	0.12848	32	0.12786	48	2069	7
	1,550	4	0.000081	34	0.03838	116	0.12918	38	0.12811	59	2072	8
	1,550	12	0.000071	28	0.03788	122	0.12959	53	0.12777	79	2068	11
08	1,450	20	0.000063	6	0.04165	40	0.12915	38	0.12829	39	2075	5
	1,500	38	0.000008	4	0.03831	23	0.12848	33	0.12838	32	2076	4
	1,550	34	0.000000	0	0.03740	14	0.12820	16	0.12820	16	2074	2
Mean (²⁰⁷Pb/²⁰⁶Pb) age (394 isotopic ratios) 2075 ± 2 Ma/USD = 1.46
PMM-06 – Charnockite
03	1,450	28	0.001491	38	0.08927	320	0.14206	28	0.12249	74	1993	11
	1,500	30	0.000093	28	0.18422	324	0.12975	31	0.12774	50	2067	7
	1,550	36	0.000119	6	0.27484	193	0.13109	21	0.12953	23	2092	3
05	1,450	36	0.000091	4	0.14548	130	0.12855	42	0.12739	57	2063	8
05	1,500	38	0.000014	2	0.25557	208	0.13000	22	0.12980	21	2096	3
06	1,500	32	0.000309	22	0.14642	159	0.13428	30	0.13001	32	2098	4
07	1,450	8	0.000139	24	0.08081	115	0.13072	56	0.12889	64	2083	9
07	1,500	36	0.000045	4	0.09981	1081	0.12972	26	0.12919	32	2087	4
Mean (²⁰⁷Pb/²⁰⁶Pb) age (142 isotopic ratios) 2094 ± 4 Ma/USD = 2.32
PMM-20A – Charnockite
01	1,500	40	0.000067	9	0.18159	122	0.13050	34	0.12925	36	2088	5
	1,550	34	0.000010	1	0.16295	83	0.12914	22	0.12912	24	2086	3
	1,570	20	0.000013	14	0.12933	4	0.12924	32	0.12920	32	2087	4
03	1,500	16	0.000041	11	0.19330	514	0.12961	53	0.12907	70	2086	10
03	1,550	36	0.000041	17	0.18553	148	0.12936	27	0.12888	28	2083	4
07	1,450	20	0.000136	7	0.14306	202	0.13019	50	0.12845	50	2077	7
	1,500	36	0.000013	5	0.21310	50	0.12845	16	0.12830	18	2075	2
	1,550	34	0.000008	1	0.17216	592	0.12901	25	0.12890	25	2083	3
08	1,500	38	0.000010	6	0.26223	72	0.12866	31	0.12856	25	2079	3
08	1,550	24	0.000006	5	0.27111	351	0.12884	42	0.12880	39	2082	5
09	1,450	08	0.000030	14	0.26798	605	0.12924	35	0.12885	40	2083	5
09	1,500	6	0.000000	0	0.24123	143	0.12955	205	0.12955	205	2092	28
10	1,550	38	0.000014	4	0.16717	287	0.12892	23	0.12875	23	2081	3
11	1,450	24	0.000009	4	0.16378	376	0.12896	48	0.12891	45	2083	6
Mean (²⁰⁷Pb/²⁰⁶Pb) age (218 isotopic ratios) 2084 ± 2 Ma/USD = 1.12
PMM-01 – Inequigranular granodiorite
02	1,500	22	0.000018	6	0.24519	79	0.12873	45	0.12856	37	2079	5
07	1,500	36	0.000016	9	0.24167	92	0.12857	40	0.12845	36	2077	5
08	1,500	12	0.000023	2	0.26118	94	0.12893	26	0.12863	28	2080	4
09	1,500	8	0.000042	8	0.38122	292	0.12894	68	0.12839	69	2076	9
Mean (²⁰⁷Pb/²⁰⁶Pb) age (78 isotopic ratios) 2079 ± 3 Ma/USD = 0.50
PMM-16 – Migmatitic paragneiss
01	1,550	38	0.000017	5	0.10241	50	0.17961	36	0.17946	39	2648	4
02	1,500	22	0.000372	31	0.18690	342	0.13397	139	0.12892	115	2084	16
03	1,500	18	0.000026	2	0.03331	103	0.17505	81	0.17492	102	2606	10
03	1,550	6	0.000000	0	0.10128	811	0.17606	117	0.17606	117	2616	11
04	1,500	38	0.000013	4	0.16720	54	0.12878	45	0.12869	53	2080	7
04	1,550	34	0.000009	6	0.14536	78	0.12845	65	0.12841	69	2077	9
05	1,500	20	0.000017	7	0.03636	49	0.17141	52	0.17118	45	2570	4
05	1,550	8	0.000000	0	0.06850	272	0.17535	415	0.17535	415	2610	39
07	1,500	34	0.000066	7	0.04377	46	0.16976	25	0.16885	31	2547	3
08	1,500	34	0.000177	4	0.38958	93	0.19955	36	0.19750	42	2806	4
09	1,500	38	0.000277	10	0.04334	44	0.16378	26	0.16019	42	2458	4
11	1,550	16	0.000160	5	0.60933	214	0.20594	46	0.20406	42	2859	3

Grain Spot	²⁰⁶Pb_c (%)	U (ppm)	Th (ppm)	²³²Th/²³⁸U	²⁰⁶Pb* (ppm)	(1) ²⁰⁶Pb/²³⁸U Age		(1) ²⁰⁷Pb/²⁰⁶Pb Age		Discordant (%)	(1) ²⁰⁷Pb/²⁰⁶Pb	± %	(1) ²⁰⁷Pb*/²³⁵U	± %	(1) ²⁰⁶Pb*/²³⁸U	± %	Errors correlation
1.1	0.08	14	11	0.81	4.78	2215	± 27	2486	± 13	11	0.1629	0.76	9.21	1.6	0.4101	1.4	0.884
2.1	7.19	34	19	0.59	6.17	1151	± 15	2351	± 46	51	0.1505	2.7	4.06	3	0.1955	1.4	0.454
2.2	2.02	54	13	0.25	17	1967	± 19	2434	± 15	19	0.158	0.88	7.77	1.4	0.3568	1.1	0.792
3.1	0.65	20	9	0.47	8.09	2510	± 28	2478	± 16	-1	0.1622	0.96	10.64	1.7	0.476	1.4	0.818
4.1	0.05	47	37	0.81	16.1	2159	± 21	2467	± 7.1	12	0.16109	0.42	8.83	1.2	0.3977	1.1	0.938
5.1	1.64	103	29	0.29	32.5	1982	± 18	2076	± 19	5	0.1284	1.1	6.372	1.5	0.3599	1.1	0.714
6.1	0.34	135	59	0.45	38.3	1835	± 17	2414	± 9.2	24	0.15611	0.54	7.089	1.2	0.3293	1.1	0.889
7.1	0.03	221	124	0.58	58.9	1740	± 16	2387	± 3.7	27	0.15369	0.22	6.568	1.1	0.3099	1	0.978
8.1	0.27	68	20	0.30	17.8	1706	± 18	2415	± 12	29	0.1562	0.7	6.526	1.4	0.303	1.2	0.860
9.1	0.11	95	23	0.25	32.6	2158	± 20	2482	± 5	13	0.16251	0.3	8.909	1.1	0.3976	1.1	0.963
10.1	0.76	42	18	0.44	16.7	2417	± 23	2482	± 22	3	0.1625	1.3	10.19	1.8	0.4549	1.1	0.652
11.1	–	18	9	0.50	7.05	2403	± 26	2478	± 10	3	0.16212	0.6	10.1	1.4	0.4518	1.3	0.909
12.1	–	76	46	0.63	32	2578	± 23	2481	± 5.3	-4	0.16238	0.32	11.01	1.1	0.4916	1.1	0.960
13.1	1.28	37	15	0.43	7.13	1300	± 14	2433	± 17	47	0.1579	1	4.862	1.6	0.2234	1.2	0.763
14.1	0.18	140	16	0.12	51.8	2297	± 22	2546	± 4.4	10	0.16882	0.26	9.97	1.2	0.4281	1.1	0.974
15.1	1.51	21	14	0.68	6.74	2015	± 22	2479	± 19	19	0.1622	1.1	8.21	1.7	0.3669	1.3	0.748
16.1	0.36	134	58	0.45	43.4	2055	± 21	2494	± 5	18	0.16369	0.3	8.48	1.2	0.3755	1.2	0.970
17.1	3.32	22	8	0.37	9.24	2506	± 27	2483	± 23	-1	0.1626	1.4	10.66	1.9	0.4751	1.3	0.686
18.1	0.09	134	31	0.24	41.6	1984	± 18	2073	± 6.2	4	0.12815	0.35	6.369	1.1	0.3604	1.1	0.950

Grain Spot	²⁰⁶Pb_c (%)	U (ppm)	Th (ppm)	²³²Th/²³⁸U	²⁰⁶Pb* (ppm)	(1) ²⁰⁶Pb/²³⁸U Age		(1) ²⁰⁷Pb/²⁰⁶Pb Age		Discordant (%)	(1) ²⁰⁷Pb/²⁰⁶Pb	± %	(1) ²⁰⁷Pb*/²³⁵U	± %	(1) ²⁰⁶Pb*/²³⁸U	± %	Errors correlation
1.1	–	274	14	0.05	91	2107	± 18	2107	± 4.1	0	0.13065	0.23	6.965	1	0.3867	1	0.974
2.1	0.29	61	36	0.61	22	2263	± 20	2541	± 6.9	11	0.16833	0.41	9.76	1.1	0.4205	1.1	0.931
3.1	–	659	33	0.05	144	1463	± 14	2173	± 10	33	0.1357	0.6	4.768	1.3	0.2548	1.1	0.879
3.2	–	52	31	0.60	14.5	1800	± 19	2541	± 13	29	0.1684	0.75	7.48	1.4	0.3221	1.2	0.847
4.1	0.11	29	20	0.72	11.7	2492	± 23	2517	± 7.4	1	0.16591	0.44	10.79	1.2	0.4718	1.1	0.928
5.1	0.88	410	22	0.06	29.1	507	± 5.6	1122	± 21	55	0.07704	1	0.869	1.5	0.08185	1.2	0.745
6.1	–	222	27	0.12	87.3	2429	± 21	2553	± 3.5	5	0.16956	0.21	10.7	1	0.4575	1	0.979
7.1	–	287	18	0.07	91.9	2044	± 18	2079	± 2.9	2	0.12859	0.17	6.617	1	0.3732	1	0.987
7.2	–	148	162	1.13	60.6	2510	± 21	2552	± 3.2	2	0.16947	0.19	11.12	1	0.476	1	0.983
8.1	0.59	26	13	0.50	10.3	2407	± 23	2449	± 12	2	0.1594	0.71	9.95	1.3	0.4527	1.1	0.845
9.1	0.15	93	33	0.36	33.9	2269	± 20	2538	± 5.7	11	0.16803	0.34	9.77	1.1	0.4218	1	0.950
10.1	0.15	48	29	0.62	18.1	2355	± 21	2520	± 7.1	7	0.16625	0.42	10.11	1.1	0.441	1.1	0.930
11.1	–	192	64	0.34	74.8	2410	± 21	2502	± 7.8	4	0.16441	0.47	10.27	1.1	0.4532	1	0.910
12.1	–	210	102	0.50	86.3	2521	± 21	2555	± 2.8	1	0.16976	0.17	11.2	1	0.4786	1	0.987
13.1	–	412	96	0.24	152	2296	± 19	2410	± 4.8	5	0.15573	0.28	9.188	1	0.4279	1	0.963
15.1	0.01	398	62	0.16	78.7	1335	± 12	2336	± 14	43	0.1491	0.8	4.731	1.3	0.2301	1	0.785
16.1	2.13	183	26	0.15	44.3	1575	± 15	2022	± 17	22	0.1245	0.99	4.752	1.4	0.2767	1	0.726
17.1	0.00	385	63	0.17	158	2519	± 21	2540	± 2.2	1	0.16818	0.13	11.09	1	0.4782	1	0.992
18.1	–	362	17	0.05	119	2088	± 18	2108	± 3	1	0.13075	0.17	6.894	1	0.3824	1	0.987
19.1	0.41	110	47	0.44	44.3	2459	± 22	2543	± 5.1	3	0.16851	0.31	10.79	1.1	0.4645	1.1	0.963
20.1	0.12	50	34	0.70	19.6	2438	± 22	2557	± 6.5	5	0.16996	0.39	10.77	1.1	0.4596	1.1	0.940
21.1	–	166	8	0.05	64.3	2405	± 21	2507	± 3.4	4	0.16496	0.2	10.28	1	0.4522	1	0.981
22.1	–	187	21	0.11	65.2	2200	± 19	2255	± 7	2	0.14227	0.41	7.979	1.1	0.4067	1	0.930

Grain Spot	²⁰⁶Pb_c (%)	U (ppm)	Th (ppm)	²³²Th/²³⁸U	²⁰⁶Pb* (ppm)	(1) ²⁰⁶Pb/²³⁸U Age		(1) ²⁰⁷Pb/²⁰⁶Pb Age		Discordant (%)	(1) ²⁰⁷Pb/²⁰⁶Pb	± %	(1) ²⁰⁷Pb*/²³⁵U	± %	(1) ²⁰⁶Pb*/²³⁸U	± %	Errors correlation
1.1	0.09	2,734	51,588	19.5	891	2072	± 23	2059	± 5.5	-1	0.12715	0.31	6.645	1.3	0.379	1.3	0.973
2.1	0.07	2,011	46,813	24.1	639	2027	± 23	2069.9	± 6.4	2	0.12794	0.36	6.518	1.4	0.3695	1.3	0.965
3.1	0.01	2,229	41,559	19.3	705	2021	± 23	2058.7	± 6.6	2	0.12713	0.37	6.454	1.4	0.3682	1.3	0.963
3.2	0.01	7,442	54,844	7.6	2410	2062	± 23	2086.8	± 4.3	1	0.12918	0.24	6.713	1.3	0.3769	1.3	0.982
4.1	0.02	2,553	42,837	17.3	800	2005	± 23	2065	± 5.4	3	0.12759	0.3	6.418	1.4	0.3648	1.3	0.974
5.1	0.05	2,563	41,759	16.8	833	2067	± 23	2059.1	± 5.6	0	0.12716	0.32	6.63	1.4	0.3781	1.3	0.972
5.2	0.05	1,242	63,033	52.5	402	2062	± 24	2057.4	± 7.4	0	0.12704	0.42	6.604	1.4	0.377	1.4	0.957
6.1	1.70	927	56,016	62.4	299	2023	± 33	2068	± 47	2	0.1278	2.7	6.5	3.3	0.3686	1.9	0.576
6.2	0.10	385	66,854	179.5	121	2004	± 28	2056	± 14	3	0.127	0.81	6.38	1.8	0.3647	1.6	0.893
7.2	0.01	1,945	53,535	28.4	624	2045	± 24	2064.6	± 6.2	1	0.12756	0.35	6.565	1.4	0.3733	1.4	0.969
8.1	0.05	1,795	35,017	20.2	576	2044	± 24	2058.1	± 6.4	1	0.12709	0.36	6.538	1.4	0.3731	1.4	0.966
9.1	0.05	2,226	62,599	29.1	716	2049	± 24	2061	± 6	1	0.1273	0.34	6.566	1.4	0.3741	1.4	0.970
10.1	0.02	2,270	42,196	19.2	741	2075	± 24	2056.1	± 5.7	-1	0.12695	0.32	6.646	1.4	0.3797	1.4	0.973
11.1	0.00	1,868	52,216	28.9	598	2043	± 24	2060.1	± 6.3	1	0.12723	0.36	6.54	1.4	0.3728	1.4	0.968
12.1	0.04	404	69,842	178.5	135	2118	± 30	2083	± 13	-2	0.12893	0.76	6.92	1.8	0.389	1.6	0.908
13.1	0.06	406	64,703	164.8	132	2075	± 30	2069	± 13	0	0.12787	0.72	6.7	1.9	0.3797	1.7	0.921
14.1	0.00	1,561	68,054	45.0	504	2056	± 24	2068.8	± 6.6	1	0.12786	0.37	6.622	1.4	0.3756	1.4	0.965
15.1	0.00	2,333	41,203	18.3	750	2048	± 24	2061.9	± 5.7	1	0.12736	0.32	6.568	1.4	0.374	1.4	0.973
15.2	0.11	444	64,647	150.3	143	2053	± 28	2060	± 13	0	0.12724	0.75	6.58	1.8	0.375	1.6	0.906
16.1	0.01	3,769	30,824	8.5	1210	2042	± 23	2056.4	± 4.8	1	0.12697	0.27	6.525	1.4	0.3728	1.3	0.980

Rock type/sample	Magmatic age (Ma)	Inherited age (Ma)	Metamorphic age (Ma)	Method/mineral
Tonalitic orthogneiss/PMM-02A	2554 ± 3		2108 ± 5	S/zr
Tonalitic orthogneiss/PMM-04B	2480 ± 9		2073 ± 11	S/zr
Monzogranite/MVD115B	2147 ± 5*			S/zr
Enderbite/PMM-09C	2114 ± 3	2573 ± 2		E/zr
Charnockite/PMM-06	2094 ± 4			E/zr
Charnockite/PMM-20A	2084 ± 2	2108 ± 5;2436 ± 33		E/zr
Migmatitic gneiss/PMM-16	2080 ± 5	2364 ± 9;2458 ± 6; 2648 ± 4;2859 ± 3		E/zr
Granodiorite/PMM-01	2079 ± 3	2157 ± 3;2415 ± 10; 2613 ± 8;2824 ± 22		E/zr
Leucogranitic vein/PMM-23A	2075 ± 2			E/zr
Pelitic paragneiss/PMM-23B			2062 ± 8	S/mnz

Sociedade Brasileira de Geologia R. do Lago, 562 - Cidade Universitária, 05466-040 São Paulo SP Brasil, Tel.: (55 11) 3459-5940 - São Paulo - SP - Brazil
E-mail: sbgeol@uol.com.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] * Corresponding author.