The Alto Moxotó Terrane of the Borborema Province presents a wide exposure of Paleoproterozoic crust, but unlike other continental blocks of South America, its orogenic history is strongly obliterated by late Neoproterozoic deformation. New isotopic and geochemical studies were conducted in mafic-ultramafic (Fazenda Carmo Suite) and granitic-gneissic rocks (Riacho do Navio Suite) within the terrane. The former present zircon U-Pb crystallization ages at ca. 2.13 Ga, whereas Sm-Nd data suggests a juvenile origin via melting of early Paleoproterozoic to Archean peridotitic sources. Geochemical data for these rocks are compatible with tholeiitic magmas with some degree of crustal contamination and trace element distribution points to a continental-arc related setting interpreted as remnants of the early stages of subduction. In contrast, the Riacho do Navio Suite was emplaced at ca. 2.08 Ga and has highly negative ε_Nd(t) values indicating crustal reworking. The suite displays calc-alkali to alkali-calcic and ferroan geochemical signatures compatible with Cordilleran magmas. In addition, trace-element distribution as well as discriminant diagrams suggest that the precursor magmas were generated during the later stages of a continental arc or in a syn-collisional setting. Based on our results, we suggest that the studied units might represent missing pieces of a Paleoproterozoic accretionary orogen that formed the crustal framework of the Alto Moxotó Terrane, and that this represents a block associated with assembly of the Nuna/Columbia Supercontinent, which is now largely hidden within the Neoproterozoic orogenic belts of West Gondwana.

Borborema省的AltoMoxotó地形具有广泛的古元古代地壳暴露，但与南美其他大陆块不同，其造山历史被新元古代后期变形强烈地掩盖了。新的同位素和地球化学研究在地层内的镁铁质超音波岩（Fazenda Carmo Suite）和花岗岩质片麻岩（Riacho do Navio Suite）中进行。前者目前的锆石U-Pb结晶年龄大约为。2.13 Ga，而Sm-Nd数据表明是通过早期古元古代向太古代的橄榄岩生源融化而形成的幼年起源。这些岩石的地球化学数据与冲蚀性岩浆兼容，并具有一定程度的地壳污染，并且痕量元素分布指向与大陆弧有关的环境，被解释为俯冲早期的残留物。相反，Riacho do Navio Suite放置在大约 2.08 Ga，且高度负ε_钕（吨）值指示地壳返工。该套件显示了与堇青石岩浆兼容的钙-碱到碱-钙和二茂铁地球化学特征。此外，痕量元素分布以及判别图表明，在一个大陆弧的后期阶段或在产生所述前体岩浆顺-collisional设置。根据我们的结果，我们建议所研究的单元可能代表了古元古代增生造山带的缺失部分，该造山带形成了AltoMoxotóTerrane的地壳框架，这代表了努纳/哥伦比亚超大陆的组装相关的块体，现在很大程度上隐藏在西冈瓦纳的新元古代造山带内。