Articles | Volume 14, issue 3
https://doi.org/10.5194/esurf-14-391-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esurf-14-391-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
OrthoSAM: multi-scale extension of the Segment Anything Model for river pebble delineation from large orthophotos
Institute of Geosciences, University of Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany
Aljoscha Rheinwalt
Institute of Geosciences, University of Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany
Bodo Bookhagen
Institute of Geosciences, University of Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany
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Sherilyn C. Fritz, André O. Sawakuchi, Anders Noren, Paul A. Baker, Cleverson Silva, Carlos Jaramillo, Renato Paes de Almeida, Liliane Janikian, Isaac Salém Bezerra, Marcos Barbosa, Dailson Bertassoli, Rain Blankenship, Cristiano M. Chiessi, Sarah J. Feakins, Maria da Glória Garcia, Cécile Gautheron, Brian Grivna, Gelvam Hartmann, Cindy Kunkel, André Marconato, Angela Martinez, Sebastian G. Marulanda, Carlos Eduardo M. Mazoca, Francisco R. Negri, Mauricio Parra, Werner E. Piller, Fabiano N. Pupim, Victor Salgado, Rachel T. So, Priscila Emerich Souza, Elena Stiles, Caroline A. E. Strömberg, Siu Mui Tsai, Ingo Wahnfried, Josh West, Marc-Élie Adaimé, Jhon Afonso, Thomas Kenji Akabane, Camila Eliza Althaus, Carlos D'Apolito, Kleiton R. Araújo, Roney da Silva de Azevedo Júnior, Jessica Barcellos, Tacio Bicudo, Giovanni Bogota, Bodo Bookhagen, Caio Breda, Alderlene Pimentel de Brito, Francy Carvajal, Daniel Antunes Coppi, Carolina Barbosa Leite da Cruz, Felipe Torres Figueiredo, Kate Freeman, Pedro Victor Oliveira Gomes, Martin Gross, Emma Hartke, Katja Heeschen, William Mozart Henrichs, Leonardo Henrique, Carina Hoorn, Brian K. Horton, Andrés Díaz-Jamamillo, Said Kamrani-Mehni, Fatima Leite, Lin Li, Rodrigo Ferreira de Lucena, Alastair Milne, Thomás Miranda, Marcelo Mota, Diana Ochoa, Vinicius de Lima Passos, Rafaela Maciel Lopes de Paula, Elisa Piispa, Angelo Plata Torres, Surangi W. Punyasena, Adriano Domingos dos Reis, Catherine Rigsby, Andrés F. Salazar Rios, Fernanda Costa Gonçalves Rodrigues, Raquel M. M. Romão, Ingrid C. Romero, Henrique O. Sawakuchi, Doug Schnurrenberger, Kristina Brady Shannon, Silane A. F. da Silva-Caminha, Clauses Sousa, Larissa Natsumi Tamura, Thomas Wiersberg, Helanlin Xiang, and Belén Zamudio
Sci. Dril., 35, 127–157, https://doi.org/10.5194/sd-35-127-2026, https://doi.org/10.5194/sd-35-127-2026, 2026
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The Trans-Amazon Drilling Project seeks to reconstruct the origins of biodiversity in the world's largest and most diverse rain forest, and the roles of landscape changes driven by Andean uplift and global climate change in diversification. We provide a project overview and preliminary results from a drill core from the Acre Basin of western Brazil, which recovered an 860 m sequence that was deposited in a large river system and which will yield critical insights on evolutionary history.
Jonas Kordt, Saptarshi Dey, Bodo Bookhagen, Georg Rugel, Johannes Lachner, Carlos Vivo-Vilches, Naveen Chauhan, and Rasmus Thiede
EGUsphere, https://doi.org/10.5194/egusphere-2026-2382, https://doi.org/10.5194/egusphere-2026-2382, 2026
This preprint is open for discussion and under review for Earth Surface Dynamics (ESurf).
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Himalayan rivers respond to climatic forcing across multiple timescales. We investigate fluvial terraces along the Ravi and Suil rivers in the western Higher Himalaya using field work and various dating methods. Results show that past sediment accumulation and incision cycles can be linked to climatic oscillations. All terrace surfaces were affected by reworking, ~2–10 times more recent than deposition, and we propose that mass wasting and glacial lake outburst floods shaped these surfaces.
Ariane Mueting, Laurane Charrier, and Bodo Bookhagen
EGUsphere, https://doi.org/10.5194/egusphere-2025-6445, https://doi.org/10.5194/egusphere-2025-6445, 2026
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Slow-moving landslides respond to seasonal climate variations, but displacement time series from optical satellite imagery often contain illumination-related biases that obscure true signals. This study assesses methods to mitigate seasonal errors and reveals kinematic changes and controlling factors of a large slow-moving landslide in the Argentinean Andes.
Aljoscha Rheinwalt, Benjamin Purinton, and Bodo Bookhagen
Earth Surf. Dynam., 13, 923–940, https://doi.org/10.5194/esurf-13-923-2025, https://doi.org/10.5194/esurf-13-923-2025, 2025
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Our study presents a computer-based method to detect and measure pebbles in 3D models reconstructed from camera photos. We tested it in a controlled setup and achieved 98 % accuracy in detecting pebbles. Unlike traditional 2D methods, our approach provides full 3D size and orientation data. This improves sediment analysis and riverbed studies by offering more precise measurements. Our work highlights the potential of 3D modeling for studying natural surfaces.
Natalie Lützow, Bretwood Higman, Martin Truffer, Bodo Bookhagen, Friedrich Knuth, Oliver Korup, Katie E. Hughes, Marten Geertsema, John J. Clague, and Georg Veh
The Cryosphere, 19, 1085–1102, https://doi.org/10.5194/tc-19-1085-2025, https://doi.org/10.5194/tc-19-1085-2025, 2025
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As the atmosphere warms, thinning glacier dams impound smaller lakes at their margins. Yet, some lakes deviate from this trend and have instead grown over time, increasing the risk of glacier floods to downstream populations and infrastructure. In this article, we examine the mechanisms behind the growth of an ice-dammed lake in Alaska. We find that the growth in size and outburst volumes is more controlled by glacier front downwaste than by overall mass loss over the entire glacier surface.
Ariane Mueting and Bodo Bookhagen
Earth Surf. Dynam., 12, 1121–1143, https://doi.org/10.5194/esurf-12-1121-2024, https://doi.org/10.5194/esurf-12-1121-2024, 2024
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This study investigates the use of optical PlanetScope data for offset tracking of the Earth's surface movement. We found that co-registration accuracy is locally degraded when outdated elevation models are used for orthorectification. To mitigate this bias, we propose to only correlate scenes acquired from common perspectives or base orthorectification on more up-to-date elevation models generated from PlanetScope data alone. This enables a more detailed analysis of landslide dynamics.
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Short summary
OrthoSAM is a new method that uses Segment Anything Model (SAM) to automatically identify and outline individual pebbles in high-resolution aerial images. OrthoSAM divides large photos into smaller sections that SAM can process effectively, and it improves the way to tell SAM where to look for objects. It uses a multi-resolution approach to handle different sizes, and it can be used to determine the distribution. Tests with computer-generated images and field data show that it is very precise.
OrthoSAM is a new method that uses Segment Anything Model (SAM) to automatically identify and...