Initial results from a Trans-Amazon Drilling Project core from the Acre Basin of Brazil
Year: 2026
Type: article
Abstract: The Trans-Amazon Drilling Project (TADP) is reconstructing the late Cenozoic history of Amazonian geology, climate, rivers, and forests. Drilling in the Acre Basin of western Brazil in 2023 recovered an 860 m drill core characterized by sediments that were deposited in a large paleo-river system. The overall sequence includes sandstones, siltstones, and mudstones that underwent varied degrees of weathering and pedogenesis. Here, we describe the ongoing geochronologic, geochemical, mineralogical, geophysical, and biotic analyses of the sedimentary record and present some preliminary inferences of the environmental history based on these initial results. Except for the uppermost ∼ 12 m, sediments from the drill core represent a single lithostratigraphic unit, assigned to the Solimões Formation, which is dominated by feldspar-rich sands of Andean origin. The pollen assemblage is quite different from Early to Middle Miocene floras that have been analyzed from a few sites elsewhere in the western Amazon. The novel pollen assemblage and new geochronological results suggest that the sequence may span the latest Miocene and all of the Pliocene Epoch, an interval that currently is not well represented in existing regional records and that is crucial for understanding the evolution of Amazonian biodiversity, as well as landscape transformations driven by Andean uplift and global climate change.
Source: Scientific Drilling
Authors: 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, Belén Zamudio
Institutions: University of Nebraska–Lincoln, Universidade de São Paulo, University of Minnesota, Continental Scientific Drilling Facility, Duke University, Universidade Federal Fluminense, Smithsonian Tropical Research Institute, Universidade Federal de São Paulo, University of Southern California, Centre National de la Recherche Scientifique, Institut des Sciences de la Terre, Institut de Recherche pour le Développement, Université Savoie Mont Blanc, Université Grenoble Alpes, Universidade Estadual de Campinas (UNICAMP), GFZ Helmholtz Centre for Geosciences, Universidade Federal do Acre, University of Graz, University of Washington, Burke Museum of Natural History and Culture, Universidade Federal do Amazonas, University of Illinois Urbana-Champaign, Universidade Federal da Grande Dourados, Universidad Distrital Francisco José de Caldas, University of Potsdam, Centro de Investigación Científica y de Educación Superior de Ensenada, Universidade Federal de Sergipe, Pennsylvania State University, Universalmuseum Joanneum, University of Amsterdam, The University of Texas at Austin, University of North Carolina at Charlotte, Edinburgh Geological Society, Universidad de Salamanca, University of Iceland, Institute of Earth Sciences, Universidade de Brasília, East Carolina University, Smithsonian Institution, National Museum of Natural History, Linköping University, Universidade Federal de Mato Grosso
Language: English
Subfield: Soil Science
Domain: Life Sciences
Open Access status: diamond
OpenAlex ID: W7166196072