We combine quartz textural analysis with Titanium-in-quartz (TitaniQ) geothermometry to investigate the late stages of deformation in mylonitic rocks from the Sucuru dike swarm in the Borborema Province. The wide range in TitaniQ temperatures (>340 to 740 °C) closely related to grain sizes are attributed to inefficient Ti resetting during bulging (BLG) and subgrain rotation (SGR) recrystallization. The highest temperature values (>500–740 °C) occur in the core of quartz ribbons and porphyroclasts. They are interpreted as the record of early-stage plastic deformation, likely during the intrusion of magmatic bodies, and are progressively overprinted during a lower-temperature stage (>340–500 °C) associated with intense dynamic recrystallization and production of a large amount of fine-grained matrix. The dominantly weak crystallographic preferred orientations (CPOs) can be attributed to a large variety in crystallographic orientations of parent grains, which control to a large extent the CPO evolution of daughter grains, and to activation of multiple slip systems in the <a > direction (basal, rhomb and prism) due to synkinematic temperature decrease. The CPOs are consistent with strain localized by operation of dislocation creep-accommodated grain boundary sliding (DisGBS) during the low-temperature stage. DisGBS seems to be less important in coarse pure quartz domains, where moderate to strong CPOs indicate the dominance of dislocation creep. Several evidence of intracrystalline deformation in quartz ribbons and porphyroclasts point to dominant activation of dislocation creep at the early high-temperature stage of deformation, with activation of prism <c>. The dike orientations, geometry and evidence of solid-state deformation in their margins, fit well with progressive E-W dextral shearing, where they intrude and crystallize in a NW-SE direction and rotate clockwise during shearing. This implies that the dextral shear regime that dominated the Borborema province from ca. 600 Ma was still in effect into the Cambrian some 60–70 million years later.

我们将石英结构分析与石英中钛 (TitaniQ) 地热学相结合，研究 Borborema 省 Sucuru 堤群中糜棱岩变形的晚期阶段。与晶粒尺寸密切相关的 TitaniQ 温度范围宽（>340 至 740 °C）归因于在鼓胀 (BLG) 和亚晶粒旋转 (SGR) 再结晶过程中钛的低效重置。最高温度值 (>500–740 °C) 出现在石英带和斑岩的核心。它们被解释为早期塑性变形的记录，可能在岩浆体侵入期间，并在与强烈动态再结晶和大量生产相关的低温阶段（> 340-500°C）逐渐叠印的细粒度矩阵。占主导地位的弱晶体择优取向 (CPO) 可归因于母晶晶体取向的变化很大，这在很大程度上控制了子晶的 CPO 演化，以及 <a> 方向上多个滑移系统的激活 (基底、菱形和棱柱）由于同运动温度降低。CPO 与在低温阶段通过位错蠕变调节晶界滑动 (DisGBS) 操作局部化的应变一致。DisGBS 在粗纯石英域中似乎不太重要，其中中到强的 CPO 表明位错蠕变占主导地位。石英带和斑碎屑中晶内变形的几个证据表明，在变形的早期高温阶段位错蠕变的主要激活，激活棱镜<c>。堤坝的方向、几何形状和边缘固态变形的证据，与渐进式非常吻合E -W 右旋剪切，它们在 NW-SE 方向侵入并结晶，并在剪切过程中顺时针旋转。这意味着从 ca 主导 Borborema 省的右旋剪切状态。大约 60-70 百万年后，600 Ma 仍然有效进入寒武纪。