This document discusses biostratigraphy, which utilizes fossils to date sediments and reconstruct past environments, highlighting the importance of microfossils in deep-sea sediment analysis. Key groups of microfossils, such as foraminifera, radiolaria, and diatoms, are detailed for their utility in biostratigraphical research. Additionally, it outlines practical exercises for identifying important radiolarian species and assessing their relevance in biostratigraphy.

1. Biostratigraphy and MicrofossilsProfessor Simon K. HaslettCentre for Excellence in Learning and TeachingSimon.haslett@newport.ac.uk1st September 2010

2. IntroductionBiostratigraphy is the use of fossils to date sediments and reconstruct past environments, and enables ages to be applied to isolated samples.Any fossil has the potential of being used biostratigraphically, however, in deep-sea sediments retrieved using coring equipment, the best fossils to use are those that are small and abundant in the core samples.Microfossils are thus the most appropriate types of fossils to use when investigating DSDP (Deep Sea Drilling Project) and ODP (Ocean Drilling Program) material.In this presentation, some of the microfossils that can be derived from deep-sea sediments and used for biostratigraphical purposes are described.

3. Quaternary microfossils: foraminiferaThere are many types of Quaternary microfossils including:Foraminifera – wholly marine Sarcodine Protozoa that secrete both calcareous and organic-cemented tests. Lives in both benthonic and planktonic modes (see Murray, 2002).

4. Quaternary microfossils: radiolariaRadiolaria – wholly marine Sarcodine Protozoa that secrete a siliceous test. Only planktonic mode of life (see Haslett, 2002).

5. Quaternary microfossils: calcareous nannofossilsCalcareous nannofossils– marine planktonic algae that secrete calcareous plates. Includes coccoliths (see Jordan, 2002).

6. Quaternary microfossils: diatomsDiatoms – algae that secrete siliceous frustules. Can live in both freshwater and marine environments, in both benthonic and planktonic modes of life (see Kennington, 2002).

7. Quaternary microfossils: ostracods and dinoflagellatesOstracods – crustaceans that secrete a bivalved calcareous carapace. Can live in both freshwater and marine environments, in both benthonic and planktonic modes of life (see Boomer, 2002).Dinoflagellates – calcareous or, more commonly, organic-walled marine algae. Planktonic, but has a benthonic resting stage (see Dale and Dale, 2002).

8. Radiolarian practical 1Part AThe purpose of these practicals is to develop your skills at identifying biostratigraphically important species of radiolaria. Using suitable Late Cenozoic samples such as those collected by the DSDP and ODP, search for the following biostratigraphically important species:The species and events that you should cover include:FAD of Amphirhopalumypsilon

9. LAD of Stichocorysperegrina

10. FAD of Lamprocyrtisneoheteroporos

11. FAD of Theocorythiumtrachelium

12. FAD of Theocalyptradavisiana

13. LAD of Pterocaniumprismatium