Full Title: Architecture of a Seismic-Scale Normal Fault Zone: The Hidden Valley Fault, Canyon Lake Gorge, Texas
Endorsed by: GSA’s Environmental and Engineering Geology, Structural Geology and Tectonics, Quaternary Geology and Geomorphology Divisions
Led by: David Ferrill, Adam Cawood
Date: Thu. 23 Oct 2025
Time: 8 a.m.-5 p.m.
CEUs: 0.8
This field trip focuses on fault zone architecture and deformation processes in the seismic-scale Hidden Valley fault zone at Canyon Lake Gorge, part of the Balcones fault system. Located approximately one hour from San Antonio, Texas, this is an exceptionally well-exposed site to observe fault and fracture networks in mechanically layered carbonates of the Cretaceous Glen Rose Formation. The Hidden Valley fault zone has provided a study area for deformation analyses for over two decades and is an excellent analog for deformation and fluid flow in mechanically layered reservoirs and aquifers. Cost includes transportation (mini vans), entrance fees, lunch, snacks, and water.
We’ll be out in the field all day, on foot and traversing uneven terrain, so please come prepared for a full day of walking, standing, and sun exposure. We’ll cover less than two miles total on foot, with approximately 300 feet of elevation change. It could be hot, so wear appropriate clothing and bring a hat and sunscreen. Sturdy walking shoes or hiking boots are required—no sandals or open-toed shoes. There may also be a chance of rain, so pack rain gear just in case. Bring a day pack to carry lunch, snacks, drinks, and other field necessities. Note that rock hammers and sample collecting are not allowed.
By purchasing this item, you are buying a seat on an in-person geological field trip.
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Learn more about this and other GSA Connects 2025 events.
For additional information, please contact Rebecca Taormina, rtaormina@geosociety.org, GSA Field Trip and Short Program Coordinator.
Product Code: FT25CN402
Product Category: FTRIP