The region of Tucuruí, northeastern Pará, is located in the transition between the Amazon Craton and the Araguaia Belt. In this region, there is an extensive graben filled by a volcano-sedimentary succession, 35 km wide that extends over 100 km in the NNW-SSE direction and which is represented by the Tucuruí Group. This group consists of a succession of basaltic flows and diabase sills interbedded with sub-arkose and siltstones. Together with the metasedimentary rocks of the Tocantins Group, these rocks represent the latest records of the Araguaia Orogen in the extreme North of Brazil. The volcanic deposits consist of basalt flows and volcanic breccias associated with diabase sills. The flows are predominantly composed of massive and locally amygdaloidal basalts and basaltic breccias. The basalts are aphanitic, fine-grained or glassy, holo-to hypocrystalline, and are made up of labradorite, augite, Fe–Ti minerals oxides, sulfides, and apatite. The massive basalts have intergranular or intersertal texture, whereas the amygdaloidal basalts are characterized by fibro-radial zeolites, epidote, and chlorite. The basaltic breccias are composed of elongated, hypovitreous basalt fragments encompassed by a volcanoclastic matrix with siltstone films and anastomosed siliceous-zeolitic materials. The basalts are subalkaline with tholeiitic Ocean Island Basalts affinity, intraplate, and are interpreted as products of fissural volcanism in a subaerial environment. Deformation is predominantly ruptile, and fluid remobilization occurs along faults and fractures, generating veins of quartz, carbonate, chlorite, and epidote by hydrothermal processes at low temperatures (anki-metamorphism). The sedimentary succession of the Tucuruí Group represents a paleo-segment formed in a shallow marine environment influenced by storm waves. The evolution of the succession is related to the installation and fill of a rift basin during the final stage of evolution of the Araguaia Belt at the Neoproterozoic/Paleozoic transition. This event is related to the extensional tectonics that marked the transition from a ductile to ruptile regime in the late stage of evolution of the Araguaia Orogen, and it represents a rare record of the end of the Brasiliano Cycle on the Brazilian Platform.

图库鲁伊地区位于帕拉州东北部，位于亚马逊克拉通和阿拉瓜亚带之间的过渡地带。在该地区，有一个广阔的地堑，被火山-沉积层序填满，宽 35 公里，沿 NNW-SSE 方向延伸超过 100 公里，以 Tucuruí 群为代表。该组由一系列玄武岩流和辉绿岩基岩与亚长石和粉砂岩互层组成。连同托坎廷斯群的变质沉积岩，这些岩石代表了巴西最北部阿拉瓜亚造山带的最新记录。火山沉积物由玄武岩流和与辉绿岩基岩相关的火山角砾岩组成。流主要由块状和局部杏仁状玄武岩和玄武角砾岩组成。玄武岩呈隐晶质、细粒或玻璃状，全至亚晶，由拉长石、辉石、Fe-Ti矿物氧化物、硫化物和磷灰石组成。块状玄武岩具有粒间或夹层结构，而杏仁状玄武岩的特征是纤维放射状沸石、绿帘石和绿泥石。玄武质角砾岩由细长的玻璃质玄武岩碎片组成，被火山碎屑基质包围，具有粉砂岩膜和吻合的硅质沸石材料。玄武岩是亚碱性的，具有拉斑海岛玄武岩的亲合力，板内，被解释为地下环境中裂隙火山作用的产物。变形主要是破裂，流体再流动沿断层和裂缝发生，通过低温热液过程（anki-变质作用）产生石英、碳酸盐、绿泥石和绿帘石脉。Tucuruí 群的沉积序列代表了在受风暴波影响的浅海海洋环境中形成的古段。序列的演化与新元古代/古生代过渡的阿拉瓜亚带演化最后阶段裂谷盆地的安装和充填有关。该事件与阿拉瓜亚造山带演化后期由韧带向破裂带转变的伸展构造有关，是巴西地台巴西利亚诺旋回结束的罕见记录。序列的演化与新元古代/古生代过渡的阿拉瓜亚带演化最后阶段裂谷盆地的安装和充填有关。该事件与阿拉瓜亚造山带演化后期由韧带向破裂带转变的伸展构造有关，是巴西地台巴西利亚诺旋回结束的罕见记录。序列的演化与新元古代/古生代过渡的阿拉瓜亚带演化最后阶段裂谷盆地的安装和充填有关。该事件与阿拉瓜亚造山带演化后期由韧带向破裂带转变的伸展构造有关，是巴西地台巴西利亚诺旋回结束的罕见记录。