The Guanhães block is one of the basement units present in the context of the Neoproterozoic West Gondwana assembly. It was reworked as a basement inlier within the Araçuaí orogen, in the margins of the São Francisco-Congo (SF-C) paleocontinent. The Guanhães block’s Rhyacian-Orosirian record is revealed for the first time by the Felício and the Mercês granitic plutons. Geophysical, petrographic, lithogeochemical and U-Pb (LA-ICPMS) analyses define and characterize these plutons, and link their genesis to the major Paleoproterozoic orogenic event that is thought to have amalgamated the SF-C paleocontinent. The Felício pluton is composed of mesocratic fine-grained epidote-biotite-granodiorite, the Mercês pluton comprises biotite-monzogranite and hornblende-syenogranite. These two plutons show different geochemical features; the Felício rocks are low-K, magnesian, calcic to calc-alkalic, metaluminous, and the Mercês rocks are rich in K, ferroan, alkali-calcic to alkalic, peraluminous, their shared common features are enrichment in LILE, LREE and HFSE and negative anomalies of Ti, Ta, Nb and P. Zircons collected from the Felício pluton granodiorite yielded a U-Pb concordia age of 2151 ± 12 Ma, interpreted as the pluton’s crystallization age. The Mercês pluton monzogranite yielded a discordia with upper intercept at 2014 ± 11 Ma and lower intercept at 539 ± 13 Ma, interpreted as the Mercês pluton’s cristallization age and the Brasiliano metamorphic overprint, respectively. Trace elements and REE signatures suggest that the magma that originated both plutons shares a common source, compatible with the metasomatization of a mantle wedge by dehydration of a subducted slab. Based on the petrographic, geochemical and geochronological data, the following tectonic scenario is suggested: subduction and accretion of the Mantiqueira arc and emplacement of the Felício pluton at c. 2.15 Ga, followed by collision, gravitational collapse of the orogen, post-collisional magmatism and emplacement of the Mercês pluton at c. 2.01 Ga. This scenario is reinforced by the regional geochemical correlations among the many coeval terranes in the eastern margin of the São Francisco craton, along the Minas-Bahia orogen. At a broader scale, these correlations can be expanded to the African counterpart, giving insights into the SF-C paleocontinent framework in the Precambrian.

Guanhães 地块是新元古代西冈瓦纳大陆组合中存在的基底单元之一。它在圣弗朗西斯科-刚果 (SF-C) 古大陆边缘的 Araçuaí 造山带内被改造成地下室。Felício 和 Mercês 花岗岩岩体首次揭示了 Guanhães 地块的 Rhyacian-Orosirian 记录。地球物理、岩石学、岩石地球化学和 U-Pb (LA-ICPMS) 分析定义和表征了这些岩体，并将它们的成因与被认为已合并 SF-C 古大陆的主要古元古代造山事件联系起来。Felício 岩体由细粒绿帘石-黑云母-花岗闪长岩组成，Mercês 岩体由黑云母-二长花岗岩和角闪石-正长花岗岩组成。这两个岩体显示出不同的地球化学特征；Felício 岩石是低钾、镁质、钙质至钙碱性、金属铝质，Mercês 岩石富含 K、铁质、碱钙至碱性、过铝质，它们的共同特征是富集 LILE、LREE 和 HFSE 和Ti、Ta、Nb 和 P 的负异常。从 Felício 岩体花岗闪长岩中收集的锆石产生了 2151 ± 12 Ma 的 U-Pb 协和年龄，解释为岩体的结晶年龄。Mercês 岩体二长花岗岩产生了一个上截距为 2014 ± 11 Ma 和下截距为 539 ± 13 Ma 的不协调，分别解释为 Mercês 岩体的结晶时代和 Brasiliano 变质叠印。微量元素和稀土元素特征表明，起源于两个岩体的岩浆共享一个共同的来源，与俯冲板片脱水引起的地幔楔交代相容。根据岩石学、地球化学和地质年代学数据，提出了以下构造情景：Mantiqueira 弧的俯冲和增生以及 Felício 岩体在 c. 的就位。2.15 Ga，随后是碰撞、造山带的重力坍塌、碰撞后岩浆作用和 Mercês 岩体在 c. 的侵位。2.01 Ga。在圣弗朗西斯科克拉通东部边缘，沿着米纳斯-巴伊亚造山带的许多同时代地体之间的区域地球化学相关性加强了这种情况。在更广泛的范围内，这些相关性可以扩展到非洲对应物，从而深入了解前寒武纪的 SF-C 古大陆框架。Mantiqueira 弧的俯冲和增生以及 Felício 岩体在 c. 的就位。2.15 Ga，随后是碰撞、造山带的重力坍塌、碰撞后岩浆作用和 Mercês 岩体在 c. 的侵位。2.01 Ga。在圣弗朗西斯科克拉通东部边缘，沿着米纳斯-巴伊亚造山带的许多同时代地体之间的区域地球化学相关性加强了这种情况。在更广泛的范围内，这些相关性可以扩展到非洲对应物，从而深入了解前寒武纪的 SF-C 古大陆框架。Mantiqueira 弧的俯冲和增生以及 Felício 岩体在 c. 的就位。2.15 Ga，随后是碰撞、造山带的重力坍塌、碰撞后岩浆作用和 Mercês 岩体在 c. 的侵位。2.01 Ga。在圣弗朗西斯科克拉通东部边缘，沿着米纳斯-巴伊亚造山带的许多同时代地体之间的区域地球化学相关性加强了这种情况。在更广泛的范围内，这些相关性可以扩展到非洲对应物，从而深入了解前寒武纪的 SF-C 古大陆框架。沿着米纳斯-巴伊亚造山带的圣弗朗西斯科克拉通东部边缘的许多同时代地体之间的区域地球化学相关性加强了这种情况。在更广泛的范围内，这些相关性可以扩展到非洲对应物，从而深入了解前寒武纪的 SF-C 古大陆框架。沿着米纳斯-巴伊亚造山带的圣弗朗西斯科克拉通东部边缘的许多同时代地体之间的区域地球化学相关性加强了这种情况。在更广泛的范围内，这些相关性可以扩展到非洲对应物，从而深入了解前寒武纪的 SF-C 古大陆框架。