Chondrites (genus)
Chondrites Temporal range:
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Illustration of Chondrites bollensis. | |
A sample of Chondrites from the Middle Silurian. | |
Trace fossil classification | |
Ichnogenus: | †Chondrites Sternberg, 1833 |
Chondrites is a
Morphology
There are four recognized Chondrites ichnospecies, however, aberrant forms of unknown taxonomic affinity have been discovered.[2] The fossils are made of infilled dendritic rootlike burrows. The branching angles are 30° to 40°, while a shaft diameter varies between 0.1 mm and 10 mm, remaining constant within a single system.[1] Chondrites is classified as a fodinichnion.[3]
Occurrence
First appearing during the Cambrian, Chondrites is still produced today. It is one of the most common ichnotaxa throughout the fossil record and is widely distributed in all types of marine
Interpretation
Though the characteristic burrows are still produced today (in deep-sea deposits), no organism has ever been observed inside them. Several theories exist regarding the origin of these structures. While some authors hypothesize Chondrites to be the product of an
The ichnogenus is found both in anaerobic, organic-rich sediments and in oxic layers, where it is almost invariably the last in the bioturbation sequence, i.e., it was placed deep within the sediments, away from oxidizing surficial and interstitial water. These suggest the trace-maker's ability to tolerate oxygen deprivation very well. Therefore, Chondrites can be used as an indicator of anoxia in sediments.[1]
References
- ^ PMID 17743196.
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- ^ Hasiotis, Stephen (2011). "Chondrites : von Strenberg, 1833". University of Kansas. Archived from the original on August 26, 2012. Retrieved April 14, 2013.
- ^ Głuszek, Arkadiusz (1998). "Trace fossils from Late Carboniferous storm deposits, Upper Silesia Coal Basin, Poland". Acta Palaeontologica Polonica. 43 (3): 517–546.
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- ^ Encinas, Alfonso; Luis A. Buatois; Kenneth L. Finger (2008). "Paleoecological and paleoenvironmental implications of a high-density Chondrites association in slope deposits of the Neogene Santo Domingo Formation, Valdivia, south-central Chile". Ameghiniana. 45 (1): 225–231.
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