Upper Cretaceous dinoflagellate cysts:
relationships to sequence stratigraphy,
sea-level change and water depth
| Executive Summary | |
|---|---|
| Researchers | Mr John Lignum (PhD Student): CEESR Dr Ian Jarvis (Director of Studies): CEESR Dr Martin Pearce (Supervisor): Statoil Norway Dr Martin Waller (Supervisor): CEESR Dr Andrew Swan (Supervisor): Kingston University |
| Funding Body/Source | Kingston University and Statoil |
| Duration | September 2004 - ongoing |
| Project Summary | This project aims to develop models that quantify sea-level change and water depth based on spatial and temporal assemblage variation in dinoflagellate cysts. The focus is on the Cenomanian Stage (100 - 94 Ma) of the Late Cretaceous. |
Background
Dinoflagellates are predominantly marine organisms, characterized by having two flagellae and a cellulose covering. They display characteristics of both plants (algae) and animals (protozoans), and form one of the chief components of modern marine plankton. Some dinoflagellates develop a hard resistant organic-wall (cyst) as part of a resting stage in their life cycle. These "dinocysts" have a high preservation potential in sediments, and provide a continuous geological record back to at least the mid-Triassic, with peak species diversity during the Late Cretaceous.
Late Cretaceous dinocysts
The Late Cretaceous was characterised by the highest eustatic sea-levels of the last 250 Myr, with sea levels estimated to be 200-300 m above those of the present day. Several episodes of rapid sea-level rise and fall occurred, with highest sea-levels being attained during the early Turonian climatic optimum. The Late Cretaceous provides a unique opportunity to examine relationships between dinoflagellate cysts and sea-level change.
 |
 |
 |
Spiniferites ramosus ramosus |
Hystrichosphaeridium pulchrum |
Pterodinium cingulatum cingulatum |
Typical Upper Cretaceous dinocysts
Recent palynological studies (e.g. Prince et al., 1999; Pearce, 2000) have provided a relatively detailed dinocyst biostratigraphic record for Upper Cretaceous chalks in NW Europe. Many workers have also examined correlations between palynomorph data and various environmental parameters (e.g. Jarvis et al., 1988; Sluijs et al., 2005).
Few studies have compared dinocyst abundance and diversity data to geochemical parameters from the host rock. The first high-resolution study (Pearce et al., 2003) to compare dinocyst species and absolute abundance data with a suite of complementary elemental and isotopic geochemical data, revealed that studies of this kind have great potential for inter-regional correlation and palaeoenvironmental interpretation. Dramatic changes in dinocyst records accompany periods of rapid sea-level change, such as those spanning the Cenomanian - Turonian boundary at 93.5 Ma.
Dinocyst and stable-isotope records across the Cenomanian/Turonian boundary
(Oceanic Anoxic Event 2) in northern Germany
Study objectives
The aim is to obtain high-resolution palynological, sedimentological and geochemical data from biostratigraphically well-constrained European sections and to use these data to produce models that will provide a basis for interpreting dinocyst assemblages as sea-level and water-depth proxies. Additional outcomes will be:
(1) an improved high-resolution biostratigraphic database for the study interval
(2) a correlation between North Boreal and Tethyan Realm biostratigraphies
(3) integrated chemostratigraphic – biostratigraphic framework for the Cenomanian
(4) a better understanding of environmental controls on dinocyst assemblages
References
Jarvis, I., Carson, G., Cooper, M.K.E., Hart, M.B., Leary, P., Tocher, B.A., Horne, D. & Rosenfeld, A., 1988. Chalk microfossil assemblages and the Cenomanian-Turonian (late Cretaceous) Oceanic Anoxic Event: new data from Dover, England. Cretaceous Research 9: 3-103.
Pearce, M.A., 2000. Palynology and chemostratigraphy of the Cenomanian to Lower Campanian chalk of southern and eastern England. Unpublished PhD thesis, Kingston University, 432 pp.
Pearce, M.A., Jarvis, I., Swan, A.R.H., Murphy, A.M., Tocher, B.A. & Edmunds, W.M., 2003. Integrating palynological and geochemical data in a new approach to paleoecological studies: Upper Cretaceous of the Banterwick Barn Chalk borehole, Berkshire, UK. Marine Micropaleontology, 47: 271-306.
Prince, I.M., Jarvis, I. & Tocher, B.A., 1999. High-resolution dinoflagellate cyst biostratigraphy of the Santonian-basal Campanian (Upper Cretaceous): new data from Whitecliff, Isle of Wight, England. Review of Palaeobotany & Palynology, 105: 143-169.
Sluijs, A., Pross, J. & Brinkhuis, H., 2005. From greenhouse to icehouse; organic-walled dinoflagellate cysts as paleoenvironmental indicators in the Paleogene. Earth-Science Reviews, 68: 281-315.
Publications
Journal articles
Lignum, J., Jarvis, I. & Pearce, M.A., 2007. A critical assessment of standard processing methods for the preparation of palynological samples. Review of Palaeobotany and Palynology doi.org/10.1016/j.revpalbo.2007.11.004
Conference presentations
Lignum, J., Jarvis, I., Pearce, M. & Swan, A., 2005. Dinoflagellate cysts as sea-level and water depth indicators: Upper Cretaceous of Culver Cliff, Isle of Wight, UK. 7th International Symposium on the Cretaceous Scientific Program and Abstracts (A. Godet, H. Mort, P. Linder & S. Bodin, Eds), September 2005, University of Neuchâtel, 127-128.
Lignum, J., Jarvis, I. & Pearce, M., 2006. Dinoflagellate cysts as sea-level and water depth indicators: Upper Cretaceous of Culver Cliff, Isle of Wight, UK. EGU General Assembly, Vienna Austria, Geophysical Research Abstracts, 8: 01326.
Lignum, J., Jarvis, I. & Pearce, M., 2007. The dinoflagellate cyst record of the Cenomanian – Turonian boundary (OAE2): data from a newly cored black shale succession, Wunstorf, northern Germany. EGU General Assembly, Vienna Austria, Geophysical Research Abstracts, 9: 3854.
Lignum, J., Jarvis, I., Pearce, M. & Wunstorf Drilling Party, 2007. Integrating palynological and geochemical data: preliminary results from a newly cored Cenomanian – Turonian (OAE2) black shale succession, Wunstorf, northern Germany, Geological Society Bicentenary Conference Abstracts, September 2007, London, 142.
Further information/links
