A revised calcareous nannofossil biozonation for the Lower Jurassic (Hettangian–Lower Pliensbachian) of NW Europe
Research output: Contribution to journal › Journal article › Research › peer-review
Documents
- Fulltext
Final published version, 3.87 MB, PDF document
The Mochras core, UK, an historic reference site for the study of Early Jurassic cal-careous nannofossils, has been reinvestigated here across the Hettangian to Lower Pliensbachian. Both relative and absolute abundances of 24 calcareous nannofossil species reveal patterns and occurrences that define not less than 37 defined biohorizons. However, due to the low abundance of many of those species towards the base and top of their stratigraphical range, we observe large inconsistencies in first and last occurrences of these species. Instead, we consider records of first consistent and last consistent occurrences (FCOs and LCOs), as well as base and top of acme events, as more reliable biohorizons. Accordingly, we assess the reliability of our biohorizons and show that, in addition to previously established zonal and sub-zonal biomarkers, nine non-zonal biohorizons prove to be robust. Based on that, an updated biozonations scheme with additional subzones for NJB has been proposed and tested against other localities.
Original language | English |
---|---|
Article number | 56.3.4 |
Journal | Lethaia: An International Journal of Palaeontology and Stratigraphy |
Volume | 56 |
Issue number | 3 |
Number of pages | 20 |
ISSN | 0024-1164 |
DOIs | |
Publication status | Published - 2023 |
Bibliographical note
Publisher Copyright:
© 2023 Author(s).
- Biostratigraphy, Coccoliths, Early Jurassic, Hettangian, Mochras Borehole, Pliensbachian
Research areas
ID: 382857935