GeoFubar

The culmination of a winter’s A-Z series. And I got a brief cameo @ approx 40 minutes in, sporting my winter Parka.

Loved this series, and being a part of it

Nick Zentner 12 likes. "The Buried Fault Beneath The Canadian Rockies"

"Seismicity and crustal strain across the Cordillera (same extent as Figure 1). Epicenters are from the official catalogs used for the Canadian and U.S. National Seismic Hazard Models (Halchuk et al., 2015; Mueller, 2018). Both catalogs are clipped at the Canada-US border to minimize duplication, and exclude offshore events. SHmax orientations are from the World Stress Map project (Heidbach et al., 2018) and the style of faulting (Aϕ)–based on relative stress magnitudes–is from Lund Snee and Zoback (2020). GNSS velocities are from Ojo et al. (2021) and are relative to stable North America, with the modeled effects of Cascadia subduction zone interseismic locking removed in the forearc region."

Source:
Finley, T., Nissen, E., Leonard, L. J., Cassidy, J. F., Prush, V., & Miller, B. (2026). Holocene normal faulting in the Southern Rocky Mountain Trench; orogenic collapse modulated by glacial unloading?Journal of Geophysical Research: Solid Earth, 131, e2025JB032339. https://doi.org/10.1029/2025JB032339

Did you know Utah is an absolute geological wonderland? 🏜️ This incredible photo captures a low-angle thrust fault perfectly exposed at Ketobe K**b, revealing exactly how immense tectonic compression forces one massive block of rock to slide right over another. From spectacular tectonic fractures like this to world-famous copper mines, Utah's rugged landscape is a fascinating open-air record of millions of years of extreme Earth-shaping forces! ⛰️🔨

🙃🙃🙃

"Cros-sections through the Revillagigedo mantle showing how the geodynamic setting has changed with time. Top: Westward subduction of the Socorro slab during the late Jurassic. At 5 Ma, the detached Socorro slab enters the lower mantle and active spreading occurs at the Mathematician ridge. Currently, a lower mantle-derived plume migrates to west around the Socorro slab and melts the mantle underneath the abandoned ridge. Bottom: P-wave tomography from the UU-P07 model (Amaru, 2007; Hall & Spakman, 2015)."

Source:
Koornneef, J. M., Tromp, L. J. J., Nikogosian, I. K., Barning, E. M., Deuss, A., Rojas-Agramonte, Y., et al. (2026). Active plume, abandoned ridge, or ancient slab? olivine-hosted melt inclusions record the mantle melting conditions below the east Pacific Revillagigedo Archipelago, Mexico. Geochemistry, Geophysics, Geosystems, 27, e2025GC012699. https://doi.org/10.1029/2025GC012699

"Fig. 17. Conceptual tectonic model for the geodynamic evolution of the Tunisian Maghrebian and Atlas orogens from the Eocene to Present. (a) Eocene-Oligocene (48–23 Ma) Eo-Alpine Phase: Subduction of Tethyan oceanic crust and the thinned African continental margin beneath the internal terranes (MM: Mesomediterranian/AlKaPeCa including La Galite). Progressive convergence drives collision and the development of foreland depocenters. A regional décollement within Triassic evaporites facilitates the SE-propagation of the Atlas fold-and-thrust belt. This stage is associated with the metamorphism of Triassic metabasites (49.78 ± 1.28 Ma; Booth-Rea et al., 2023) and the UHP metamorphism of the subducted African crust (32.3 ± 3.3 Ma; Bruguier et al., 2017). (b) Early-Middle Miocene (23–12 Ma) Neo-Alpine: Lithospheric delamination beneath the internal domain triggers crustal collapse and calco-alkaline magmatism (14–12 Ma). Buoyancy-driven ascent of UHP rocks occurs concurrently. The Tellian and Numidian nappes overthrust the Atlas foreland, while underthrusting and metamorphism affect the Atlas basement (23–17 Ma; Ksingle bondAr dating, Bellon and Perthuisot, 1977). (c) Late Miocene (12–6 Ma): Post-orogenic collapse and regional extension dominate Tunisia Tell and Mejerda Basins. Crustal thinning and asthenospheric upwelling induce bimodal magmatism and the exhumation of HP metamorphic rocks. Despite this extension at the rear of the wedge, continued plate convergence drives shortening farther SE into the Tunisian Atlas. (d) Pliocene-Quaternary (6–0 Ma) Recent tectonic Phase: Renewed convergence and shortening remodel the northern Tunisian margin, potentially due to the onset of southward subduction. Strike-slip fault reactivation accompanies the rejuvenation of the Tellian, Mejerda, and Atlas systems. The late Miocene thin crust (see Fig. 16) is reactive by a transpressional to transtensional stress regime, marking the latest phase of orogenic evolution."

Source:
Arfaoui, M. S., & Gharbi, M. (2026). Syn-convergent extension and deformation coupling in the Middle Mejerda basins (NW-Tunisia): Insights into polyphase evolution within the Tunisian orogenic wedge. Tectonophysics, 231112.