Sedimentology and geochemistry of the contact between the Napo and Tena formations at the Puerto Napo outcrop, Tena: deciphering changes in depositional conditions in the Oriente Basin, Ecuador
Synopsis
This study characterizes the contact between the Napo and Tena formations at the Puerto Napo outcrop in the Oriente Basin of Ecuador through sedimentological, petrographic, and geochemical analyses. The results indicate that the boundary between both units corresponds to a gradual transition, without evidence of erosive surfaces or unconformities. The Napo Formation is composed of carbonate lithologies with abundant planktonic microfauna, whereas the Tena Formation is dominated by siliciclastic sandstones and siltstones with Andean terrigenous input and volcanic fragments. Geochemical profiles (Ca/Fe, Ca/Si, Ca/Ti, Ca/Al, Ca/Sr) display a gradual trend from the Napo to the Tena formations, reflecting the progressive decrease in marine influence and the increase in continental input. Total organic carbon (TOC) showed variability within the Napo Formation, with values reaching up to 0.8%, whereas the Tena Formation exhibited low and stable values (0.1–0.3%). Magnetic susceptibility presented low values in the Napo Formation, associated with a marine carbonate-dominated environment, and higher values in the Tena Formation, linked to a greater content of ferromagnesian minerals. These results support the interpretation of a transitional contact related to a transgressive–regressive event during the Maastrichtian, controlled by eustatic and tectonic processes.
Downloads
Pages
cter.e10
Published
May 25, 2026
Categories
Copyright (c) 2026 Zulay Marina Niño Ruiz, Laura Inés Salazar Cotugno (Coordinador de obra); Patricia Yissel Dávalos Cerrón, Azucena Chanatasig, Felipe Cerrera, Andrea Carolina Palacios Rosado, Mateo Patricio Sánchez Sanaguano, Liliana Paulina Lalaleo Córdova, William Calero Cáceres, Santiago Casado, Joshua Pazmiño, Jaime Martí-Herrero, Rocio Cecibel Jiménez Paute, Kevin Campaña, Elena Coyago-Cruz, Andrea Hidalgo-Dávila, Lizbeth Alpusig-Guanoluisa, Belén Apolo, Felipe Rivera-Rueda, Yerovi Sánchez-Arias, Karen Marcella García, Rubianith Suárez, Harol Smith Daza, Geovanna Tafurt, Duverney de Jesús Chaverra, Edita Valle, Evelyn Oña, Mishel Calero, Jonathan Liria, Andrés Sebastian Calderón Velasco, Roque Rivas-Párraga, Inti Llumiquinga, Ana Bravo, Julio Rea, Máximo Moreira, Oscar Vivanco, Nicole Jara, Lilibeth Carrión, Stefanía Cevallos, Paulo Herrera, Esteban Patricio Romero Valladares, Ana Paula Rosero-Jácome, Eliza Jara-Negrete, Gabriel Picón Nava, Nelly Paredes, Wilfredo Ramiro Franco, Wilmer Shiguango, Willin Álvarez, Juan Ponce, Jessica Sánchez, Christian Israel Andrade Romero, Alexandra Vargas, David Sanchez, Negover Briñez, Byron García, Dennis Tomalá, Mery Ramirez, Jenny Rodríguez, Paúl Tufiño Mateus, Enrique Laaz, Willan Revelo, Cecilia Puertas, Juan Andrés Guadamud, Karina Olalla-Tacuri , Darwin Omar Yánez Avalos, Diana Callejas, Sara Álvarez, John Mauricio Castillo Torres, Edith Pamela Tapia Pruna, Daniela Endara, Carolina Castro, Silvia Alejandra Llerena Gordillo, Kevin Stwart Tulcanaza Ruiz, Noroska G.S. Mogollón, Melany Ochoa, María Cristina Peñuela, Jimmy Yumbo, Enith Yánez, Carolina Ñacato, Samira Lluno, Henry Conteron, Pedro Cadena, Corina Campos, Oswaldo Guzman, Micaela Campos, Cindy Vera, Dayana Vera, Christian Coral, Bruce Tumbaco, María Soledad Solorzano, Bryan Valencia, José Sebastián Araujo Soria, Sandra Torres, Enzo Loor, Oscar Ayala, Darwin Rosero, Amparo Condor, Luis Cáceres, Miguel Flores, Elena Ulcuango, Nicole Pilco, David Galarza, Mishell Cabrera, Julieth Chancay, Paola Soto, David Portillo, Diana Cisneros, José Aguirre-Déleg, Pablo Maita-Zambrano, Aimee Delgado-Cruz, Myrian Larco, María Soledad Salazar, María Susana Grijalva, Viviana Stefanía Cárdenas Loor, Mónica Dazzini Langdon, Sheila Tobar Vallejo, Vinicio Velásquez Zambrano, Juan Carlos Soria Aguas (Autor de capítulo)
License
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
How to Cite
Sedimentology and geochemistry of the contact between the Napo and Tena formations at the Puerto Napo outcrop, Tena: deciphering changes in depositional conditions in the Oriente Basin, Ecuador. (2026). In III International Congress of Biotechnology and Neotropical Ecosystems (p. cter.e10). Editorial Unión Científica. https://doi.org/10.63804/CIBEN.25.cter.e10
