Pseudofossil

Pseudofossil

Pseudofossils are inorganic objects, markings, or impressions that might be mistaken for fossils. Pseudofossils may be misleading, as some types of mineral deposits can mimic lifeforms by forming what appear to be highly detailed or organized structures. One common example is when manganese oxides crystallize with a characteristic treelike or dendritic pattern along a rock fracture. The formation of frost dendrites on a window is another common example of this crystal growth. Concretions are sometimes thought to be fossils, and occasionally one contains a fossil, but are generally not fossils themselves. Chert or flint nodules in limestone can often take forms that resemble fossils.

Pyrite disks or spindles are sometimes mistaken for fossils of sand dollars or other forms (see marcasite). Cracks, bumps, gas bubbles, and such can be difficult to distinguish from true fossils. Specimens which cannot be attributed with certainty to either the fossils or the pseudofossils are treated as dubiofossils. Debates about whether specific forms are pseudo or true fossils can be lengthy and difficult. For example, "Eozoön" is a complex laminated form of interlayered calcite and serpentine originally found in Precambrian metamorphosed limestones (marbles). It was at first thought to be the remains of a giant fossil protozoan (Dawson, 1865), then being by far the oldest fossil known. Similar structures were subsequently found in metamorphosed limestone blocks ejected during an eruption of Mt. Vesuvius. It was clear that high-temperature physical and chemical processes were responsible for the formation of "Eozoön" in the carbonate rock (O'Brien, 1970). The debate over the interpretation of "Eozoon" was a significant episode in the history of paleontology (Adelman, 2007).

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Look at other dictionaries:

  • pseudofossil — noun Any natural object that resembles a fossil …   Wiktionary

  • Manganese — Not to be confused with Magnesium. This article is about the chemical element. For the ghost town, see Manganese, Minnesota. For the steamship, see SS Manganese. chromium ← manganese → iron ↑ Mn ↓ Tc …   Wikipedia

  • Eozoon canadense — Eozoön canadense (literally, dawn animal of Canada ) is a pseudofossil.John William Dawson (1865) described the banded structures of coarsely crystalline calcite and serpentine as a gigantic Foraminifera, making it the oldest known fossil. It was …   Wikipedia

  • Dubiofossil — The term dubiofossil is a portmanteau word used in geology and paleontology for a problematic structure that looks like a fossil, but whose biologic origin is uncertain. (From Latin dubius, + fossil). It has been mainly used for remains found in… …   Wikipedia

  • Petrosomatoglyph — This footprint carved into the rock on Dunadd, in Argyll, is linked to the crowning of the Scots kings of Dál Riata. A petrosomatoglyph is an image of parts of a human or animal body incised in rock. Many were created by Celtic peoples, such as… …   Wikipedia

  • ψευδοαπολίθωμα — το, Ν (παλαιοντ.) αντικείμενο, δομή ή ορυκτό, ανόργανης προέλευσης που μοιάζει με απολίθωμα ή θεωρείται, εσφαλμένα, ως τέτοιο. [ΕΤΥΜΟΛ. Νόθο αντιδάνειο σύνθετο, πρβλ. αγγλ. pseudofossil] …   Dictionary of Greek

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