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The Transbrasiliano‐Kandi‐4°50′ (TK4) shear zone in western Gondwana crosscuts South America and NW Africa for at least 6000 km. Despite its impressive size, the timing of the main episode of dextral ductile shearing is uncertain. We present detailed in situ multi‐mineral geochronology of mylonites from both Brazil and Algeria supporting that the TK4 represents a near‐synchronous transcontinental shear zone system. While U–Pb zircon dates represent Archean to Neoproterozoic protolith crystallization and high‐grade metamorphism ages that are not reset during mid‐temperature shearing, dextral ductile shearing is constrained by metamorphic apatite U–Pb and syn‐kinematic biotite Rb‐Sr dates averaging 511 ± 16 and 505 ± 7 Ma, respectively. Thus, ca. 30–60 Ma after the last collisional events at ca. 570–540 Ma, the whole Brasiliano/PanAfrican orogen was reworked through the development of early Cambrian major interlinked systems of strike‐slip shear zones (keirogens).
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Caxito et al. (2025) studied this question.
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