34 Recent Advances in the Gulf of California Oblique Rift: Offshore and Onshore Studies // Avances Recientes en el Rift Oblicuo del Golfo de California: Estudios Marinos y Terrestres (Posters)

This session highlights recent research on the Gulf of California–Salton Trough plate boundary from ~12 Ma to today. We welcome terrestrial and marine studies involving tectonics, basin analysis, volcanology, sedimentology, and more. English or Spanish.

Friday, 24 April 2026
8:00 AM - 5:30 PM
LMH, 5th Floor Chapel

Spatial Variability of Heat Flow in Hydrothermal Systems of the Southern Pescadero Basin, Gulf of California

Paper number: 34-5
Program: Technical Sessions
Time: 8:00 AM – 8:00 AM

Authors

Abstract

The Gulf of California is an active transtensional plate boundary characterized by normal and strike-slip faulting that generates a series of pull-apart basins. Crustal thinning, magmatic intrusions, and high sedimentation rates associated with this tectonic regime strongly influence the thermal structure of the lithosphere and promote the development of sediment-hosted hydrothermal systems. In these settings, hydrothermal circulation is closely linked to fault networks, magmatic heat sources, and variations in sediment permeability, playing a key role in lithospheric heat dissipation and fluid–rock interactions.

The Southern Pescadero Basin (SPB) is a deep-water basin within the Pescadero Basin Complex in the southern Gulf of California, where transtensional deformation and crustal thinning have produced a highly fractured and thermally anomalous seafloor. This tectonic configuration has facilitated the development of the Auka and JaichMaa ’ja’ag hydrothermal vent fields. High-resolution bathymetry and shallow acoustic profiles reveal sediment cover over crystalline basement, major fault structures, and laterally extensive acoustically transparent zones interpreted as subsurface hydrothermal fluid accumulations. The spatial association between these features, elevated heat flow, and active venting suggests the presence of a magmatic heat source, likely linked to sill emplacement or shallow magmatic intrusions that drive hydrothermal circulation.

Building on this structural framework, this ongoing study integrates sub-bottom profiling and direct heat flow measurements to investigate the thermal and hydrological processes governing fluid circulation in the SPB. While the presence of venting is documented, the spatial variability of heat flow and its relationship with sediment properties and fault-controlled permeability are not yet fully understood. This research aims to quantify spatial variations in heat flow and assess the role of sedimentary and structural controls in regulating hydrothermal circulation. Ultimately, this work contributes to a deeper understanding of how sediment-hosted systems dissipate lithospheric heat and support unique chemosynthetic ecosystems.

Geological Society of America Abstracts with Programs. Vol. 58, No. 3

doi: 10.1130/abs/2026CD-410900

© Copyright 2026 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.