Tectonic role of the Maria Magdalena Rise in regional extension

Ascertain the tectonic role of the Maria Magdalena Rise in the NE–SW-oriented extensional regime between Los Cabos and Puerto Vallarta after approximately 6 Ma, particularly whether and how this rise contributed to the development of a wide area of extension at the mouth of the Gulf of California.

Background

The study discusses that, after ca. 6 Ma, faults between Los Cabos and Puerto Vallarta were mainly oriented NE–SW due to extension at the mouth of the Gulf of California, which also led to eastward expansion and continental crustal thinning.

Although the orientation of the Maria Magdalena Rise parallels major troughs and local structural trends, the authors state that its specific role in this extensional setting remains unclear, motivating the need to resolve its tectonic significance.

References

In this scenario, the role of the Maria Magdalena Rise is unclear, but its orientation (azimuth 025°; Lonsdale, 1989) parallel to the Tamayo and Nayarit troughs, both adjacent to the mainland Mexico, as well as the structural trend of the María Madre Island (Escalona-Alcázar et al., 2014), suggests a wide area of extension.

— Crustal Structure Across the Northern Region of the Islas Marias Archipelago  (2402.06462 - Madrigal et al., 2024) in Discussion (paragraph relating the regional extension and structural trends)