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8: Measuring Geological Time (Exercises)

  • Page ID
    2047
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    Q8.1 Cross-Cutting Relationships [SE]

    ex8-1-300x269.png

    Relative ages: 2: oldest: 3: middle, 1: youngest [SE]

    Q8.2 Dating Rocks Using Index Fossils

    ex8-2-233x300.png

    Dating from overlapping fossils [SE]

    Probable age: 92.6 to 92.7 Ma. If M. subhercynius was not present the interpreted age range would be 92.6 to 92.9 Ma

    Q8.3 Isotopic Dating

    ex8-3-300x182.png

    Isotopic dating [SE]

    With a ratio of 0.91 the age is 175 Ma (red dotted line)

    Q8.4 Magnetic Dating

    The possible age ranges are 3.05 to 3.12 Ma and 1.78 to2.00 Ma

    ex8-4-300x89.png

    Dating based on magnetic-reversal chronology [SE]

    8.5 What Happened on Your Birthday?

    Answers will vary.


    8: Measuring Geological Time (Exercises) is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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