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2019-12-17 13:13:45.0 [tstevens] Insert Concept
add broader relation (STAGE 3 [16e234b5-5ecb-4e03-b4ec-7a5e03db8017,532335] - SERIES
2 [c98a4c91-1b1d-464d-8380-497a186db7eb,532299]);
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2019-12-19 08:03:24.0 [tstevens]
insert Definition (id: null
text: Cambrian Stage 3 is the still unnamed third stage of the Cambrian. It succeeds
Cambrian Stage 2 and precedes Cambrian Stage 4, although neither its base nor top
have been formally defined. The plan is for its lower boundary to correspond approximately
to the first appearance of trilobites, about 521 million years ago, though the globally
asynchronous appearance of trilobites warrants the use of a separate, globally synchronous
marker to define the base. The upper boundary and beginning of Cambrian Stage 4 is
informally defined as the first appearance of the trilobite genera Olenellus or Redlichia
around 514 million years ago.
language code: en);
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| definition |
Cambrian Stage 3 is the still unnamed third stage of the Cambrian. It succeeds Cambrian
Stage 2 and precedes Cambrian Stage 4, although neither its base nor top have been
formally defined. The plan is for its lower boundary to correspond approximately to
the first appearance of trilobites, about 521 million years ago, though the globally
asynchronous appearance of trilobites warrants the use of a separate, globally synchronous
marker to define the base. The upper boundary and beginning of Cambrian Stage 4 is
informally defined as the first appearance of the trilobite genera Olenellus or Redlichia
around 514 million years ago.
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chronounits original |
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