Full title: FT26CD05. Revisiting the Mesozoic Subduction Complex of the Vizcaíno Peninsula
Leader(s): Manuel Contreras-López, Vanessa Colás, Luis J. Gutiérrez-Trejo, Rogelio Hernández-Vergara, Elisa Fitz-Díaz, Mario A. Ramos-Arias, Megan Mueller
Endorser(s): GSA Mineralogy, Geochemistry, Petrology, and Volcanology Division, GSA Geochronology Division, GSA Structural Geology and Tectonics Division, Unión Geofísica Mexicana (UGM), GSA International
CEUs: 3.2
Date(s): Sat–Tue, 25–28 Apr.
Location: La Misión Hotel, Loreto, Baja California Sur, Mexico
Start Time: 8 a.m.(first day)
End Time: 5 p.m.(last day)
Description: The Mesozoic subduction complex of the Vizcaíno Peninsula, Baja California Sur, NW Mexico, preserves one of the most well-exposed and extensive ophiolite outcrops in the country. This four-day field trip offers an opportunity to observe the architecture and discuss the petrogenesis and tectonic evolution of the complex. Additionally, the geology of this area provides a valuable framework for regional correlation with the Franciscan Complex, contributing to broader paleogeographic reconstructions of the western margin of North America. The ophiolite consists of three tectonically dismembered sections, from base to top: serpentinized ultramafic rocks, intrusive ultramafic-mafic units, and extrusive igneous rocks with associated sedimentary cover, overlain by Cretaceous forearc deposits. The first and last days will consist of a 7-h drive from Loreto to Bahía Asunción and back. On the second day, we will visit outcrops near Puerto Nuevo: the mafic-ultramafic section, followed by the serpentinite mélange, which includes blocks of medium- to high-grade metamorphic rocks. We will also examine the Late Cretaceous sedimentary forearc cover (Valle Group). The third day will focus on the San Roque pluton (Lower Jurassic arc magmatism), which intruded the San Pablo amphibolite, and then, the supposedly upper part of the ophiolite sequence at San Hipólito, including pillow lavas and the overlying sedimentary rocks (i.e., chert, limestones, and sandstones).
Considerations: Outcrops are all accessible either along the roadside or via a short hike across terrains with loose gravel. Proper footwear and walking sticks are recommended. Cost includes round-trip transportation from Loreto (La Misión Hotel meeting location) in off-road capable vehicles, three nights of modest hotel (double occupancy) in the fishing town of Bahía Asunción, water, and meals (breakfast, lunch, and dinner included). Please note that breakfast on the first day and dinner on the fourth day are not included.
By purchasing this item, you are buying a seat for an in-person geological field trip
Field Trips offer Continuing Education Units (CEUs). One CEU equals 10 hours of participation in an organized continuing education experience under responsible sponsorship, capable direction, and qualified instruction.
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Product Code: FT26CD05
Product Category: FTRIP