Author(s)

Marilia Hagen¹, Anibal Azevedo²

¹Instituto de Física, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil.
²Faculdade de Ciencias Aplicadas da Unicamp, Limeira, Brazil.

This investigation searches the possible connections between deep and ultra-deep earthquakes in a subduction zone with unique characteristics known as Nazca-South America subduction. The earthquake events occurred in an area under the South Atlantic Magnetic Anomaly. The results pointed out that the cyclicity of earthquakes is independent of external factors and linked to internal unknown changes traced or associated with the lithosphere and upper mantle. The malleable minerals or unbreakable material could be due to a bulge of water between the two Nazca slabs sinking. The periodicity noticed from some events is opposite to the Solar Cycles, which means they enhance during the minima of cycles. Therefore, we concluded that these variations might be linked to internal causes below the crust into the lithosphere.

Nazca-South America Subduction, Seasonality, Deep-Depth Earthquakes

Hagen, M. and Azevedo, A. (2023) South Atlantic Anomaly Variations during Seasons. Natural Science, 15, 207-221. doi: 10.4236/ns.2023.157016.