Procedures for diatom analyses and hydrodynamic separation of extreme wave paleo-deposits from tropical sediment environments

0566176 - GLÚ 2024 RIV NL eng J - Journal Article
Černý, Jan - Ramírez-Herrera, M.-T. - Caballero, M.
Procedures for diatom analyses and hydrodynamic separation of extreme wave paleo-deposits from tropical sediment environments.
Marine Geology. Roč. 455, January 2023 (2023), č. článku 106970. ISSN 0025-3227. E-ISSN 1872-6151
Institutional support: RVO:67985831
Keywords : Diatom analysis techniques * Hydrodynamic separation * Humid tropics * Extreme-wave deposits * Paleo-environments * Tsunami deposits
OECD category: Geology
Impact factor: 2.9, year: 2022
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S0025322722002419

Diatoms are an important proxy in tsunami and storm research studies to determine potential sediment source and changes in environments pre- and post-event. However, the use of this proxy has proven challenging when studying extreme wave paleo events in sediments from the humid tropics because of the scarcity of diatoms in sand beds, and in clay or silt beds above and below. This problem has been associated with (1) dissolution of diatom valves in the humid tropics, (2) rate of burial and poor preservation of tsunami deposits, and (3) sediment and diatom size. Here we propose a practical solution to this problem – using hydrodynamic separation in the analysis of diatoms of extreme wave paleo-deposits. We compare diatom identification results from selected sand beds and units above and below, collected in a humid tropical environment (Guerrero, Mexico) using a standard procedure and the proposed fast hydrodynamic separation procedure to concentrate diatom-sized fraction. Thanks to the newly proposed methodology, the results showed a significant improvement in the number of observed diatom data in the studied sand units. We discuss two different techniques to achieve this aim and suggest how improvements on the quantitative research of diatoms from extreme wave deposits, particularly tsunamis, from the humid tropics.
Permanent Link: https://hdl.handle.net/11104/0337597