| System (period) | Series (epoch) | Stage (age) | Lower boundary, Ma | |
|---|---|---|---|---|
| Cretaceous | Lower | Berriasian | ~145 | |
| Jurassic | Upper (Late) | Tithonian | 149.2±0.7 | |
| Kimmeridgian |  154.8±0.8
| |||
| Oxfordian | 161.5±1.0 | |||
| Middle | Callovian | 165.3±1.1 | ||
| Bathonian | 168.2±1.2
| |||
| Bajocian | 170.9±0.8
| |||
| Aalenian | 174.7±0.8
| |||
| Lower (Early) | Toarcian | 184.2±0.3
| ||
| Pliensbachian | 192.9±0.3
| |||
| Sinemurian | 199.5±0.3
| |||
| Hettangian | 201.4±0.2
| |||
| Triassic | Upper | Rhaetian | older | |
| Subdivisions and "golden spikes" according to IUGS as of September 2023[1] | ||||
Late Jurrasic Earth
The Late Jurassic is the third and last epoch of the Jurassic period, corresponding to the Upper Jurassic series of the Jurassic system in stratigraphy. It lasted from 161.5 ± 1.0 Ma (million years ago) to ~145 Ma (IUGS 2023). It is preceded by the Callovian age of the Middle Jurassic and is followed by the Berriasian age of the Early Cretaceous. It was an epoch when the great number of sauropterygian, sauropod, theropod and stegosaurid species lived on Earth.
In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic epoch. In the past, Malm was also used to indicate the unit of geoologic/chronostratigraphic chart.
Definition[]
As of 2024, there is no GSSP defining the base of the Upper Jurassic series and the Oxfordian stage. The candidate is Thuoux Section in France with the first appearance of the ammonite Brightia thuouxensis as the possible marker of the lower boundary of this series.[2] Earlier, Ham Cliff near Redcliff Point in Dorset, England, was also suggested as GSSP of the Upper Jurassic/Oxfordian.[3]
Subdivisions[]
The Upper Jurassic divided into three stages: Oxfordian, Kimmeridgian and Tithonian. In geochronology, all of them correspond to the same ages.
Paleogeography[]
The divergence of Laurasia and Gondwana continued. The sea level rose, ledding to the formation of new sea straits and islands. The Arabian Peninsula and almost all of Europe were under water, and Hindustan had not yet separated from Gondwana. The similarity of fauna on different continents means that in this epoch there were still close connections between the continents.
Climate[]
The climate remained warm. Rising sea levels contributed to the humidification of areas previously remote from the coasts. Due to these conditions, lush vegetation developed throughout the planet, capable of feeding huge numbers of herbivores.
Late Jurassic life[]
The seas were inhabited by a great variety of cephalopods, which were hunted by bony fish, sharks, and marine reptiles. Due to the warm climate, they spread throughout the global ocean. Ichthyosaurs of the family Ophthalmosauridae fed mainly on small animals. The highly articulated skeleton and large eyes are signs that they could dive to great depths and hunt in low light. The largest marine predators were pliosaurids and thalattosuchians, related to modern crocodiles. The coasts and continental regions were populated by flying long-tailed pterosaurs, among which relatively large forms appeared with a wingspan of up to 3-4 m. Salamanders, already similar to modern ones, lived in rivers and lakes. Stegosaurids and herds of huge sauropods roamed all continents, feeding on ferns and gymnosperms. Large theropods hunted them, although some adapted to feeding on fish, as evidenced by their smooth-edged, crocodile-like teeth. Specific group, Coelurosauria, gave rise to first avials, which include birds. First ceratopsians like Yinlong also appeared in the Late Jurassic. Mammals remained small, although their evolution was actively proceeding, and among them there already existed specialized herbivore and carnivore forms.
List of life forms[]
Listed here are only a few of the many Late Jurassic animals:
- Camarasaurus, a large herbivorous sauropod dinosaur from North America.
- Mamenchisaurus, a sauropod found in China.
- Allosaurus, the most common late Jurassic theropod of North America, also present in Europe.
- Apatosaurus, a large herbivorous sauropod dinosaur from North America.
- Brachiosaurus, a large herbivorous sauropod dinosaur from North America.
- Brontosaurus, a large herbivorous sauropod dinosaur from North America.
- Diplodocus, a large herbivorous sauropod dinosaur from North America.
- Barosaurus, a large herbivorous sauropod dinosaur from North America.
- Europasaurus, a small herbivorous sauropod dinosaur from Europe.
- Saurophaganax, possibly the biggest land Jurassic predator.
- Supersaurus, possibly the largest North American sauropod of them all.
- Dicraeosaurus, a large herbivorous sauropod dinosaur from Africa.
- Giraffatitan, another large sauropod from Africa.
- Epanterias, one of the largest Jurassic carnivores, from North America (possibly just Allosaurus).
- Torvosaurus, a large Jurassic carnivore, from North America and Europe.
- Ceratosaurus, a medium-sized Jurassic carnivore of North America, Europe, and possibly Africa.
- Compsognathus, a small theropod from Europe.
- Yangchuanosaurus, a large theropod from Asia.
- Tuojiangosaurus, a thyreophoran from Asia.
- Stegosaurus, a thyreophoran from North America and Europe.
- Dryosaurus, a North American ornithopod.
- Camptosaurus, an ornithopod from North America and possibly Europe.
- Gargoyleosaurus, a thyreophoran from North America.
- Archaeopteryx, one the first known birds (avialans), from Europe.
- Rhamphorhynchus a long-tailed pterosaur from Europe.
- Pterodactylus, a short-tailed pterosaur from Europe.
- Ophthalmosaurus, a very common sea-going ichthyosaur from what is now Europe and North America.
- Liopleurodon, a medium sized sea-going pliosaur from what is now Europe.
- Perisphinctes, an ammonite.
References[]
- ↑ "Latest version of international chronostratigraphic chart". International Commission on Stratigraphy. https://stratigraphy.org/chart#latest-version.
- ↑ "GSSP Table - Mesozoic Era". https://timescalefoundation.org/gssp/index.php?parentid=35.
- ↑ K. Page, G. Melendez, M. Hart, G. Price, J. Wright, P. Bown, J. Bello (2009). "Integrated stratigraphical study of the candidate Oxfordian Global Stratotype Section and Point (GSSP) at Redcliff Point, Weymouth, Dorset, UK". Volumina Jurassica, Vol. VII. pp. 101-111