Publications by authors named "A Tassara"

Mantle xenoliths usually represent fragments derived from the depleted and degassed lithospheric mantle with He/He isotope ratios (6 ± 1 R) lower than those of mid-ocean ridge basalts (8 ± 1 R). Otherwise, basalts from oceanic islands related to hotspots often have high He/He ratios (>10 R), suggesting a deep and pristine undegassed mantle source. Here we present a striking high-He/He component (up to 27.

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Over million years, convergence between the Nazca and South America tectonic plates results in Andean orogeny. Over decades/centuries, it fuels the earthquake cycle of the Andean megathrust. It is well recognised that, over the geologically-long term of million years, Andean orogeny feeds back onto plate convergence rates, generating temporal changes documented throughout the Neogene.

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The Andean cordillera was constructed during compressive tectonic events, whose causes and controls remain unclear. Exploring a possible link to plate convergence has been impeded by the coarse temporal resolution of existing plate kinematic models. Here we show that the Neogene evolution of the Andean margin is primarily related to changes in convergence as observed in new high-resolution plate reconstructions.

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