Catastrophic slab loss in southwestern Pangea preserved in the mantle and igneous record

This study investigates the origin of the Choiyoi Magmatic Province's silicic magmatism in southwestern Pangea during the mid-Permian-Triassic. By integrating plate-kinematic reconstructions, lower mantle slab records, geochronological information, and geochemical data analysis, the authors demonstrate that this magmatic event was caused by a large-scale slab loss. A paleogeographic coincidence between a reconstructed slab gap and the Choiyoi Magmatic Province, along with geochemical data indicating a slab break-off fingerprint, support this conclusion. The findings establish the Choiyoi Magmatic Province as the oldest example of a geophysically constrained slab loss event and offer new insights into the geodynamic setting of silicic large igneous provinces in the late Paleozoic.

Guido M. Gianni, César R. Navarrete