Asked by: Bouchara Babeshkin
science geology

What are the characteristics of a useful index fossil?

Last Updated: 12th May, 2020

A useful index fossil must be distinctive oreasily recognizable, abundant, and have a wide geographicdistribution and a short range through time. Index fossilsare the basis for defining boundaries in the geologic time scaleand for the correlation of strata.

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Regarding this, what are three characteristics of a good index fossil?

A good index fossil is one with fourcharacteristics: it is distinctive, widespread, abundant,and limited in geologic time. Because most fossil-bearingrocks formed in the ocean, the major index fossils aremarine organisms. That being said, certain land organisms areuseful in young rocks and specific regions.

Additionally, how do you identify an index fossil? Identify Index Fossils

  1. They know it is about the same age as any other rock layersthat contain the same index fossil.
  2. * An index fossil must have lived for a relatively short periodof time an in many place.
  3. If geologists identify an index fossil in a rock layer, theycan be pretty sure of the age of the rock layer in which it wasfound.

Beside above, what is an index fossil used for?

Index fossils (also known as guide fossilsor indicator fossils) are fossils used to define andidentify geologic periods (or faunal stages). Index fossilsmust have a short vertical range, wide geographic distribution andrapid evolutionary trends.

What is an index fossil example?

Index fossils are commonly found, widelydistributed fossils that are limited in time span.Examples of index fossils include: Ammonites werecommon during the Mesozoic Era (245 to 65 mya), They were not foundafter the Cretaceous period, as they went extinct during the K-Textinction (65 mya).

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What is an index fossil and why are they important?

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How do you find a good index fossil?

A good index fossil is found in a wide geologicalrange. Scientists look for fossils all across the world. Ifa new fossil is found in the same strata as an indexfossil, then the new fossil's age can be correlated totime period during which the index fossillived.

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How do you describe a fossil?

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What are the four different types of fossils?

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What is the law of superposition and how is it used?

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Which unit of geologic time is the longest?

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Where did the index fossil ammonites live?

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Why is an index fossil useful?

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What is meant by the absolute age of rock?

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Why are index fossils useful for dating rocks?

Index fossils are used to identify layersof rocks. In other words, a certain layer will containfossils that are unique to that layer. Geologists haveslowly, using different methods been able to determine the age ofthe rock layers. Once the age of the rock is knownthen the age of the fossil in that layer isknown.

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Are trilobites index fossils?

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Why is the law of superposition important?

This Law of Superposition is fundamental to theinterpretation of Earth history, because at any one location itindicates the relative ages of rock layers and the fossils in them.Layered rocks form when particles settle from water orair.

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What is the largest time period in the history of Earth?

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What is an index fossil quizlet?

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What is Zone fossil?

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What is fossil assemblage?

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What type of fossil is a trilobite?

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What is a fossil record?

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