-
primary eonothems,
arranged chronologically from the most
ancient to the most recent:
Hadean Archean Proterozoic Phanerozoic Collectively,
these eonothems encapsulate...
-
Erathems are not
often used in practice.
While they are
subdivisions of
eonothems and are
themselves subdivided into systems,
dating experts prefer the...
-
usage Global (ICS)
Definition Chronological unit Eon
Stratigraphic unit
Eonothem First proposed by
Preston Cloud, 1972 Time span
formality Formal Lower...
- used ICS Time
Scale Definition Chronological unit Eon
Stratigraphic unit
Eonothem Time span
formality Formal Lower boundary definition Ten
oldest U-Pb zircon...
-
largest geochronologic time unit and is
equivalent to a
chronostratigraphic eonothem.
There are four
formally defined eons: the Hadean, Archean, Proterozoic...
- used ICS Time
Scale Definition Chronological unit Eon
Stratigraphic unit
Eonothem Time span
formality Formal Lower boundary definition Defined Chronometrically...
-
chronostratigraphy Time
spans in
geochronology Notes to
geochronological units Eonothem Eon 4 total, half a
billion years or more
Erathem Era 10 defined, several...
-
chronostratigraphy Time
spans in
geochronology Notes to
geochronological units Eonothem Eon 4 total, half a
billion years or more
Erathem Era 10 defined, several...
- The
Huainan biota is a
collection of
macroscopic organisms discovered in the
early 1980s in the
Precambrian deposits of
China (Huainan City, An**** Province)...
- The
Doushantuo Formation (formerly
transcribed as
Toushantuo or Toushantou, from Chinese: 陡山沱; pinyin: dǒu shān tuó; lit. 'steep
mountain bay') is a geological...
