Because it was a deep-focus earthquake, shaking occurred over an extensive area, including San Juan, Bogotá, Caracas, Buenos Aires, and São Paulo; it was felt as far north as Mexico City.

[5] A study completed by Dziewonski and Gilbert (1974) determined that the earthquake had featured isotropic compression, or an increase in density near the rupture point similar to an implosion;[6] this was released to great controversy.

Many studies have reached differing conclusions including a dearth of isotropic movement, and many scientists feel that resolution created errors in Dziewonski and Gilbert's findings.

[7] In 1997, Russakoff, Ekstrom, and Tromp reassessed their findings utilizing more advanced equipment that factored in shear wave splitting and coupling (the measure of how tightly locked two sides of a fault or plate are) and confirmed that there was very little isotropic compression.

[5] Gómez Tapias, Jorge; Montes Ramírez, Nohora E.; Almanza Meléndez, María F.; Alcárcel Gutiérrez, Fernando A.; Madrid Montoya, César A.; Diederix, Hans (2015).