Late Jurassic

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System/
Period
Series/
Epoch
Stage/
Age
Age (Ma)
CretaceousLower/
Early
Berriasianyounger
JurassicUpper/
Late
Tithonian145.0–152.1
Kimmeridgian152.1–157.3
Oxfordian157.3–163.5
Mid/
Middle
Callovian163.5–166.1
Bathonian166.1–168.3
Bajocian168.3–170.3
Aalenian170.3–174.1
Lower/
Early
Toarcian174.1–182.7
Pliensbachian182.7–190.8
Sinemurian190.8–199.3
Hettangian199.3–201.3
TriassicUpper/
Late
Rhaetianolder
Subdivision of the Jurassic system
according to the IUGS, as of July 2012.

The Late Jurassic is the third epoch of the Jurassic period, and it spans the geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago (Ma), which is preserved in Upper Jurassic strata.[1] In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age. In the past, this name was also used to indicate the unit of geological time, but this usage is now discouraged to make a clear distinction between lithostratigraphic and geochronologic/chronostratigraphic units.

Subdivisions[edit]

The Late Jurassic is divided into three ages, which correspond with the three (faunal) stages of Upper Jurassic rock:

  Tithonian(150.8 ± 4.0 – 145.5 ± 4.0 Ma)
  Kimmeridgian(155.7 ± 4.0 – 150.8 ± 4.0 Ma)
  Oxfordian(161.2 ± 4.0 – 155.7 ± 4.0 Ma)

Paleogeography[edit]

During the Late Jurassic epoch, Pangaea broke up into two supercontinents, Laurasia to the north, and Gondwana to the south. The result of this break-up was the spawning of the Atlantic Ocean. However, at this time, the Atlantic Ocean was relatively narrow.

Life forms of the epoch[edit]

This epoch is well known for many famous types of dinosaurs, such as the sauropods, the theropods, the thyreophorans, and the ornithopods. Other animals, such as crocodiles and the first birds, appeared in the Jurassic. Listed here are only a few of the many Jurassic animals:

References[edit]

  1. ^ Owen 1987.
Jurassic Period
Lower/Early JurassicMiddle JurassicUpper/Late Jurassic
Hettangian | Sinemurian
Pliensbachian | Toarcian
Aalenian | Bajocian
Bathonian | Callovian
Oxfordian | Kimmeridgian
Tithonian