Morphology of buried volcanic bodies in a sedimentary basin of the Pacific Continental Shelf (Gulf of California, Mexico)

Large volumes of magma emplaced and deposited within sedimentary basins can affect the architecture and geological evolution of the latter. Over the last decade, continuous improvements in techniques such as the seismic evaluation of igneous bodies have helped increase the knowledge about the architecture of volcanic systems buried in sedimentary basins. We present a part of the architecture of the characteristics of igneous bodies in the Mazatl & PRIME;an basin of the Pacific shelf located in the coastal of the Sinaloa and Nayarit states, Mexico. This basin is part of the southeastern region of the Gulf of California (GC) extensional province zone, in the vicinity of the active subduction zone of the Rivera Plate. Multichannel two-dimensional (2D) reflection seismic profiles provide information on igneous bodies, which also includes data from one borehole. The Pacific Continental Shelf Volcanic System contains the only intraplate-type volcanic manifestation reported in the GC, the Isabel Island. We show the location of faults, volcanic bodies and sills embedded in the sediments and hydrothermal vents emerging on the surface, to explain the evolution of this shelf from emplacement to complete burial in the host sedimentary basin. The plumbing system of the shelf comprised saucer-shaped sills, dikes, sill swarms and strata deformed by intrusions. We infer that the mapped basin vents reflect the presence ofa volcano that we call Nayar, buried by sediments and that is a submarine equivalent to a crater-type volcano. Additionally, analyzing the cone of the Ceboruco volcano, we can say that the shape of these cones is similar, correlating with what has been reported for volcanoes in the sedimentary basins. The Bouguer anomaly map reveals that the Nayar volcano and Aramara bulge are closely related. Insights from the architecture of the continental shelf can be used to explore natural resources such as hydrocarbons, geothermal energy, and minerals in the buried and active volcanic systems. Understanding the relationships between these diverse architectural elements will allow in the future the reconstruction of the complete architecture, including its shallow (<3 km) plumbing system, the morphology of the volcanoes, and their impact on the host sedimentary basin during burial.