Epoch: Difference between revisions

Latest revision as of 07:02, 29 March 2024

The formal geochronologic unit, longer than a geologic age and shorter than a geologic period, during which the rocks of the corresponding series were formed (from Glossary of Geology 1997).
A term used informally to designate a length (usually short) of geological time, for example, glacial epoch.
In paleomagnetism, a date to which measurements of a time-varying quantity are referred, for example, "a chart of magnetic declination for epoch 1965.0," or informally as a magnetic polarity epoch.
Magnetic polarity refers to whether the geomagnetic field was like it is today (normal polarity) or whether the north and south poles are reversed from their present configuration (reversed polarity).
American Geological Institute 1997. Glossary of Geology. 4th ed., J. A. Jackson, Ed., . p. 213.

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+#The formal geochronologic unit, longer than a [[geologic age]] and shorter than a [[geologic period|geologic  period]], during which the rocks of the corresponding series were formed (from Glossary of Geology  1997).<br/>
-  <div class="term">
+#A term used informally to designate a length (usually short) of geological time, for example,  [[glacial epoch]].<br/>
-== epoch ==
+#In [[paleomagnetism]], a date to which measurements of a time-varying quantity are referred,  for example, "a [[chart]] of [[magnetic declination]] for epoch 1965.0," or informally as a magnetic  [[polarity]] epoch.<br/> Magnetic polarity refers to whether the geomagnetic field was like it is today (normal polarity)  or whether the north and south poles are reversed from their present configuration (reversed  polarity).<br/> American Geological Institute 1997. Glossary of Geology. 4th ed., J. A. Jackson, Ed., . p. 213.
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-#<div class="definition"><div class="short_definition">The formal geochronologic unit, longer than a [[geologic age]] and shorter than a [[geologic  period]], during which the rocks of the corresponding series were formed (from Glossary of Geology  1997).</div><br/> </div>
-#<div class="definition"><div class="short_definition">A term used informally to designate a length (usually short) of geological time, for example,  [[glacial epoch]].</div><br/> </div>
-#<div class="definition"><div class="short_definition">In [[paleomagnetism]], a date to which measurements of a time-varying quantity are referred,  for example, "a [[chart]] of [[magnetic declination]] for epoch 1965.0," or informally as a magnetic  [[polarity]] epoch.</div><br/> <div class="paragraph">Magnetic polarity refers to whether the geomagnetic field was like it is today (normal polarity)  or whether the north and south poles are reversed from their present configuration (reversed  polarity).</div><br/> </div><div class="reference">American Geological Institute 1997. Glossary of Geology. 4th ed., J. A. Jackson, Ed., . p. 213. </div><br/>
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