Provenance and correlation of Permian successions from the Falkland/Malvinas Islands with West Gondwana: implications for a Natal Embayment palaeo-location

Detrital zircon U–Pb and Lu–Hf data from the youngest (late Permian) sedimentary succession of the Falkland/Malvinas Islands are used to constrain the depositional age, provenance and palaeogeography, and to test the Natal Embayment model for the Falkland/Malvinas Islands microplate. The late Permian was a period of extensive magmatism and sediment recycling along the accretionary margin of West Gondwana. Deposition into retro-arc foreland basins was widespread across South Africa, Antarctica, South America and the Falklands Islands, forming thick successions of fluvial, deltaic and shallow marine units. Our analysis links the late Permian ( c . 260 Ma) Bay of Harbours Formation of the Falkland/Malvinas Islands with deltaic/fluvial volcaniclastic units from the Karoo Basin of South Africa, the Theron Mountains of East Antarctica and the sandstones of the Ellsworth Mountains and southern Antarctic Peninsula. These units all have a shared provenance from the Antarctic sector of the West Gondwana margin. Although the detrital zircon age profiles of the Falkland/Malvinas Islands sedimentary units overlap with those from the accretionary and volcanic complexes of Patagonia, the Lu–Hf isotope compositions are clearly distinct, indicating that there was no direct link between the late Permian successions of the Falkland/Malvinas Islands ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="IM1" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> Hf −3 to +3) to the volcano-sedimentary successions of southern South America ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="IM2" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> Hf less than −5).