Two bioerosion ichnofacies produced by early and late burial associated with sea-level change
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In bioerosion, as in trace fossils as a whole, deeply emplaced structures have greater survival value than shallow structures. That is to say, tiering (the relative depth to which rasping, etching and boring organisms penetrate their substrate) is of paramount importance for the preservation potential of individual trace fossils. An Entobia ichnofacies is established for trace fossil assemblages dominated by deep tier borings and arising from long-term bioerosion, such as occurs on sediment-free submarine cliffs or hardgrounds. A Gnathichnus ichnofacies comprises assemblages containing all tiers, including superficial sculptures produced by radulation that have very little preservation potential. Such assemblages occur in short-term bioerosion situations as on shell surfaces and hardgrounds buried early by sedimentation.
Key wordsBioerosion Ichnofacies Sea-level change Burial rates Pliocene
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- Bottjer DJ, Ausich WI (1982) Tiering and sampling requirements in paleocommunity reconstruction. Proceedings of the North American Paleontological Convention. Vol. 1: 57–59Google Scholar
- Bromley RG (1990) Trace fossils: biology and taphonomy. Unwin Hyman, London: 280 ppGoogle Scholar
- Bromley RG (1992) Bioerosion: eating rocks for fun and profit. In: Maples CJ, West RR (eds) Trace Fossils. Short Courses in Paleontology No. 5. Paleontological Society: 121–129Google Scholar
- Bromley, RG, Asgaard U (1991) Ichnofacies: a mixture of taphofacies and biofacies. Lethaia 24: 153–163Google Scholar
- Bromley RG, Asgaard U. Endolithic community replacement on a Pliocene rocky coast. Ichnos 2: 93–116.Google Scholar
- Bromley RG, Ekdale AA (1986) Composite ichnofabrics and tiering of burrows. Geol Mag 123: 59–65Google Scholar
- Fischer R (1981) Bioerosion of basalt of the Pacific coast of Costa Rica. Senckenbergiana Maritima 13: 1–41Google Scholar
- Frey RW, Seilacher A (1980) Uniformity in marine invertebrate ichnology. Lethaia 13: 183–207Google Scholar
- Jarvis I, Bromley RG, Clayton C (1982) Sedimentology of the Suzanne Hardground, northern France: colonization and diagenesis of an early Campanian (Upper Cretaceous) seafloor [abstract]. International Association of Sedimentologists 3rd European Meeting, Copenhagen 1992: 15–16Google Scholar
- Seilacher A (1992) Quo vadis, ichnology? In: Maples CJ, West RR, (eds.) Trace Fossils. Short Courses in Paleontology No. 5. Paleontological Society: 224–238Google Scholar
- Wetzel A, Aigner T (1986) Stratigraphic completeness: tiered trace fossils provide a measuring stick. Geology 14: 234–237Google Scholar