Data from marine sediment core SISMAORE-CS05

This study investigates the Late Quaternary sedimentary and volcanic history of Zélée and Geyser Seamounts, carbonate platforms in the Mozambique Channel of the southwest Indian Ocean. Situated in a region influenced by active tectonics, glacial-interglacial sea level cycles, and persistent volcanic activity from both local (Mayotte and Comoros Archipelago) and regional (Madagascar) sources, these seamounts exhibit complex sedimentary and geomorphic characteristics. Using sediment cores and seismic profiles, the research identifies four glacial-interglacial stages and trace shifts in sediment provenance, documenting a transition from Madagascar-derived siliciclastic inputs to volcanic sediments associated with Mayotte volcanism around 150 ka.
The analysis also tests two models of the platform formation: one proposing a single volcanic structure fractured by tectonic activity, and another suggesting two independently formed edifices with tectonically controlled morphology. Detailed geomorphological mapping reveals steep slopes, terraces, volcanic cones, and erosional features, while seismic profiles show stratified deposits including turbidites of distinctly different origins. These turbidites highlight episodic sediment transport, with volcanoclastic layers linked to volcanic events, siliciclastic layers tracing back to Madagascar, and calciturbidites reflecting carbonate shedding from Zélée and Geyser during sea level changes.
The findings enhance our understanding of carbonate platform evolution in tectonically active marine environments, emphasizing the influence of volcanism, tectonics, and climatic fluctuations on sediment distribution and platform morphology. This study contributes a refined perspective on sedimentary processes and sediment provenance in carbonate platforms, with broader implications for reconstructing past oceanographic conditions in similar regions.