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Ichnofacies
An ichnofacies is an assemblage of trace fossils that provides an indication of the conditions that their formative organisms inhabited. Concept Trace fossil assemblages are far from random; the range of fossils recorded in association is constrained by the environment in which the trace-making organisms dwelt. Palaeontologist Adolf Seilacher pioneered the concept of ichnofacies, whereby the state of a sedimentary system at its time of deposition could be deduced by noting the trace fossils in association with one another. Significance Ichnofacies can provide information about water depth, salinity, turbidity and energy. In general, traces found in shallower water are vertical, those in deeper water are more horizontal and patterned. This is partly because of the relative abundance of suspended food particles, such as plankton, in the shallower waters of the photic zone, and partly because vertical burrows are more secure in the turbulent conditions of shallow water. In deepe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psilonichnus
An ichnofacies is an assemblage of trace fossils that provides an indication of the conditions that their formative organisms inhabited. Concept Trace fossil assemblages are far from random; the range of fossils recorded in association is constrained by the environment in which the trace-making organisms dwelt. Palaeontologist Adolf Seilacher pioneered the concept of ichnofacies, whereby the state of a sedimentary system at its time of deposition could be deduced by noting the trace fossils in association with one another. Significance Ichnofacies can provide information about water depth, salinity, turbidity and energy. In general, traces found in shallower water are vertical, those in deeper water are more horizontal and patterned. This is partly because of the relative abundance of suspended food particles, such as plankton, in the shallower waters of the photic zone, and partly because vertical burrows are more secure in the turbulent conditions of shallow water. In deepe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trace Fossil
A trace fossil, also known as an ichnofossil (; from el, ἴχνος ''ikhnos'' "trace, track"), is a fossil record of biological activity but not the preserved remains of the plant or animal itself. Trace fossils contrast with body fossils, which are the fossilized remains of parts of organisms' bodies, usually altered by later chemical activity or mineralization. The study of such trace fossils is ichnology and is the work of ichnologists. Trace fossils may consist of impressions made on or in the substrate by an organism. For example, burrows, borings (bioerosion), urolites (erosion caused by evacuation of liquid wastes), footprints and feeding marks and root cavities may all be trace fossils. The term in its broadest sense also includes the remains of other organic material produced by an organism; for example coprolites (fossilized droppings) or chemical markers (sedimentological structures produced by biological means; for example, the formation of stromatolites). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiomorpha
''Ophiomorpha'' is an ichnotaxon, usually interpreted as a burrow of an organism (specifically a crustacean) living in the near-shore environment. The burrow lining is more or less smooth on the inside, and densely to strongly mammalated or nodose on the outside, due to the packing of fecal pellets for support of the burrow. Branching is irregular but Y-shaped where present. It (particularly ''O. nodosa'') is often considered part of the Skolithos ichnofacies, where it has occurred (i.e. nearshore environments) since the early Permian, though it (particularly ''O. rudis'') has also occurred in deep water settings (Nereites ichnofacies) since the Late Jurassic, such as well-oxygenated turbidites. More generally ''Ophiomorpha ''and other crustacean-generated burrows first become prominent in the Jurassic. See also * Trace fossil A trace fossil, also known as an ichnofossil (; from el, ἴχνος ''ikhnos'' "trace, track"), is a fossil record of biological activity but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adolf Seilacher
Adolf "Dolf" Seilacher (February 24, 1925 – April 26, 2014) was a German palaeontologist who worked in evolutionary and ecological palaeobiology for over 60 years. He is best known for his contributions to the study of trace fossils; constructional morphology and structuralism; biostratinomy, '' Lagerstätten'' and the Ediacaran biota. Career Seilacher worked for his doctorate under Otto Heinrich Schindewolf, at the University of Tübingen. He was also influenced by local palaeontologist Otto Linck. He served in World War II and resumed his studies at Tübingen, corresponding with the French ichnologist, Jacques Lessertisseur. Gaining his doctorate in 1951 on trace fossils, Seilacher moved to the University of Frankfurt (1957) and then the University of Baghdad before taking up a chair in palaeontology in Göttingen. He returned to Tübingen in 1964 as the successor to Schindewolf. After 1987 he held an Adjunct Professorship at Yale University. Significant work Seilacher's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nereites Irregularis
''Nereites'' is a genus of trace fossil. Modern tracemakers of incipient ''Nereites'' include worm-like organisms,Seilacher, A., 2007. Trace Fossil Analysis. Springer, Berlin, Heidelberg (226 pp.) horseshoe crabsMartin, A.J., Rindsberg, A.K., 2007. Arthropod Tracemakers of Nereites? Neoichnological observations of juvenile limulids and their paleoichnological applications. In: Miller III, W. (Ed.), Trace Fossils. Concepts, Problems, Prospects. Elsevier, Amsterdam, pp. 478–491. and hermit crabs.Baucon A., Felletti F. 2013. Neoichnology of a barrier-island system: the Mula di Muggia (Grado lagoon, Italy). Palaeogeography, Palaeoclimatology, Palaeoecology 375. Abstract available from http://www.tracemaker.com Traditionally, two models have been proposed for ''Nereites'': # in the ‘worm model’, ''Nereites'' is a feeding burrow produced by wormlike organisms, probing and backfilling laterally # in the ‘arthropod model’, the characteristic lobes are pressure-release structur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skolithos
''Skolithos'' (formerly spelled ''Scolithus'' or ''Skolithus'') is a common trace fossil ichnogenus that is, or was originally, an approximately vertical cylindrical burrow. It is produced by a variety of organisms in shallow marine environments globally and appear as lineated features in sedimentary rocks. Depositional environments ''Skolithos'' burrows range in age from early Cambrian to the present and are found throughout the world. They occur in sediments and sedimentary rocks, primarily sands and sandstones. They are typically marine in origin, and are commonly associated with high-energy environments close to the shoreline. They have also been reported from freshwater lacustrine settings, but have rarely been described from carbonate rocks. Vertical ''Skolithos'' burrows can also occur in alluvial sediments such as braided river deposits, where the periodic fluctuation of water is an important factor in the formation of this structure. This periodic water fluctuatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoophycos
''Zoophycos'' is a somewhat cosmopolitan ichnogenus thought to be produced by moving and feeding polychaete worms. Appearance ''Zoophycos'' occurs in two forms, one planar, and one which resembles a corkscrew. In the latter helicoidal form, successive turns have larger or smaller radii. A marginal tube surrounds the perimeter of the corkscrew, linked to the vertical shaft that connects the burrow to the surface. Spreiten occur between the marginal tube and the corkscrew axis. The burrows can exceed a metre in vertical and horizontal dimension. Ethology One hypothesis proposes that ''Zoophycos'' represents gardening behaviour, in a similar fashion to '' Palaeodictyon''. According to this view, there should be a fractionation of carbon isotopes between the burrow infills and the matrix – but such differentiation was not observed in Quaternary instances from deep-water cores off the Portuguese coast.(Variation in morphology between different zoophycos 'species' means tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirorhaphe
''Spirorhaphe'' (sometimes misspelt ''Spiroraphe'') is an ichnogenus of spiraling burrows. It is associated with the '' Nereites'' ichnofacies, which is interpreted as an indicator of deep-sea, pelagic, turbidity current A turbidity current is most typically an underwater current of usually rapidly moving, sediment-laden water moving down a slope; although current research (2018) indicates that water-saturated sediment may be the primary actor in the process. T ...-dominated systems. It is one of the most common graphoglyptid traces found in modern ocean beds. References Trace fossils Paleozoic life of Ontario Paleozoic life of Manitoba Paleozoic life of Quebec {{paleo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jindongornipes
''Jindongornipes'' was a Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ... bird ichnogenus. Similar fossil footprints have been discovered in the Dunvegan Formation of British Columbia. These were among the first known Cretaceous fossil bird tracks in western Canada. Footnotes References * McCrea, R. T. and W. A S. Sarjeant. 2001. New ichnotaxa of bird and mammal footprints from the Lower Cretaceous (Albian) Gates Formation of Alberta; pp. 453–478 in D. H. Tanke, and K. Carpenter, (eds.), Mesozoic Vertebrate Life. Indiana University Press, Bloomington and Indianapolis. Bird trace fossils {{trace-fossil-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grallator
''Grallator'' GRA-luh-tor"is an ichnogenus (form taxon based on footprints) which covers a common type of small, three-toed print made by a variety of bipedal theropod dinosaurs. ''Grallator''-type footprints have been found in formations dating from the Early Triassic through to the early Cretaceous periods. They are found in the United States, Canada, Europe, Australia, Brazil ( Sousa and Santa Maria Formations) and China,''Grallator'' at .org but are most abundant on the east coast of North America, especially the and |
Chelichnus
''Chelichnus'' is an ichnogenus of Permian tetrapod footprint. The name means ''tortoise traces'', because the shape of the prints was originally mistakenly thought to be produced by a tortoise. This is now known to be incorrect, as tortoises did not evolve until much later. It was first found in Corncockle Quarry in Dumfries, Scotland, and described by Rev. Henry Duncan. In ichnology, footprints and other traces are given a genus and species name, the ichnogenus and ichnospecies, that is based on the shape of the print. However, it is almost impossible to match a trackmark to the animal that made it. ''Chelichnus'' has been argued to belong to either a therapsid Therapsida is a major group of eupelycosaurian synapsids that includes mammals, their ancestors and relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more ..., or a reptile.McKeever, PJ. 1994. The behavioural and biostratigr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scolicia
''Scolicia'' de Quartrefages, 1849 is a parataxon of ichnofossils present in sedimentary rock Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...s of marine, marginal lacustrine, alluvial, or fluvial facies. These fossil traces appear in a wide geological range, from the Cambrian to the present. ''Scolicia'' traces appear as horizontal, bilaterally symmetrical, meandering trails, variably shaped, ridgelike or ribbon like, about 1-5 centimeters wide. The trail consists of two parallel and identical in width stripes with variable trasversal ribs and a central channel. Although the term ''Scolicia'' is the most common for this type of trails or burrows in some cases, when the transverse ribbing is not very clear, it is used for the positive impression (epirelief) the term ''Palae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
