Significance of time-averaging for palaeocommunity analysis
Article first published online: 9 OCT 2007
Volume 23, Issue 2, pages 143–152, April 1990
How to Cite
FüRSlCH, F. T. and ABERHAN, M. (1990), Significance of time-averaging for palaeocommunity analysis. Lethaia, 23: 143–152. doi: 10.1111/j.1502-3931.1990.tb01355.x
- Issue published online: 9 OCT 2007
- Article first published online: 9 OCT 2007
Fürsich, F. T. & Aberhan, M. 1990 04 15: Significance of time-averaging for palaeo community analysis. Lethaia, Vol. 23, pp. 143–152. Oslo. ISSN 0024–1164.
Time-averaging caused by sedimentological, biological, or digenetic factors is widespread in marine environments. It can be recognized using stratigraphic, ecological, taphonomic, or sedimcntologic criteria. Community parameters such as diversity, relative abundance of species, taxonomic and, to a lesser extent, trophic and life habit composition may seriously differ between thanatocoenosis (death assemblage) and time-averaged taphocoenosis, depending on the degree of community stability. Time-averaged community relics have a quality different from that of Recent communities and any comparison between the two has to take this into account. Whereas allochthonous time-averaging, which is strongly related to the energy level, is particularly common in very shallow environments, the importance of autochthonous time-averaging, related in addition to the rate of net sedimentation, increases with distance from the shore and with depth. Short-term time-averaging (in the order of up to several thousand years) prevails in near shore shallow environments, whilst long-term time-averaging (in the order of 104 to 105 years) becomes more important towards lower shelf and deep sea environments.