Nemegt Formation

Nemegt Formation as it appears in the third segment of Freshwater

* Some areas in Saudi Arabia, e.g. Al-'Ula city, Medina Province and Tabuk City, Tabuk Region (Badlands, Segments 2 and 4)

## Characteristics

### Environment

Badlands, Desert, Floodplain, Fluvial, Forest, Lacustrine, Swamp

***“ In parts of Central Asia, heavy seasonal rains fill the rivers until eventually, they overflow their banks. The surrounding plains are flooded. ”***

― **David Attenborough**, *Freshwater*
The **Nemegt Formation** (also known as **Nemegtskaya Svita**) is a formation located in the Gobi Desert of Mongolia, succeeding the Barun Goyot Formation. It is one of the most known and most heavily-studied Late Cretaceous formations of Mongolia.

## Description

In sharp contrast with the past (Barun Goyot Formation) and present (Gobi Desert) states of the area, the Nemegt Formation shows evidence of a humid environment with large river channels, tidal flats, and forests. Ancient floodplains, lakes, and streams carved out canyons and steep cliffs from the sedimentary rocks in the region, and serve as suitable habitats for fish, turtles, crocodiles, and other freshwater animals. The wet climate is enough to provide a rich region that can sustain even large animals, hence, massive dinosaurs like *Therizinosaurus*, *Deinocheirus*, hadrosaurs, and even titanosaurs can be found here.

***“ The badlands of the Prehistoric Planet tests even dinosaurs to their limits. This strange landscape, carved by scouring winds and vast, ancient rivers might appear empty of life. ”***

― **David Attenborough**, *Badlands*
However, the area is also known to have undergone periodic droughts, and there is precedence for arid regions much like the Gobi Desert today existing in Mongolia during those times.

The Nemegt Formation is usually interpreted as being around 70 million years old. In 2023, however, isotopic analysis of five *Tarbosaurus* teeth appeared to have adjusted its age estimates to be around 66.7 million years. However, further clarification confirmed that these findings were not advocating the idea that the Nemegt Formation is 66.7 million years old, and the isotopic analysis of the five *Tarbosaurus* teeth simply confirmed that the Nemegt Formation could not be younger than 66.7 million years. While it is still possible that the region lasted until the end of the Mesozoic Era, until further proof is found, the Nemegt Formation's proper interpreted age is to remain as 70 million years old.

## Appearances

The Nemegt Formation serves as the setting of the second, third and fourth segments of Deserts, the first and third segments of Freshwater, the sixth segment of Forests, and the second and fourth segments of Badlands.

Contrary to popular belief, the first segment of Swamps, stated to be set in northeast Asia, does not depict the Nemegt Formation, but the obscure Songliao Basin of China, which was recently dated to be around 85 - 83 million years old, around 11 - 13 million years before the Maastrichtian time range of the show (72 - 66 million years ago).

## Fauna

*Barsboldia sicinskii**Deinocheirus mirificus*EnantiornitheansMongolian AzhdarchidMongolian LizardMongolian Titan*Mononykus olecranus*Nemegt Forest Titanosaur (possibly *Opisthocoelicaudia*)*Nemegtosaurus mongoliensis**Prenocephale prenes**Tarbosaurus bataar**Tarchia teresae**Therizinosaurus cheloniformis*"*Velociraptor*"
## References

1. ↑ 1.0 1.1 Holtz, Thomas (@TomHoltzPaleo) (June 3, 2023) on Twitter, clarifying that the age of the Nemegt Formation was never revised to be around 66 million years old
2. ↑ BTS: Apple TV+'s Prehistoric Planet
3. ↑ Those close-ups are where it all lives and breathes
4. ↑ I Know Dino: The Big Dinosaur Podcast, Episode 444: Dinosaurs in the Badlands: Featuring 2 Producers from Prehistoric Planet 2
5. ↑ Apatite U–Pb dating of dinosaur teeth from the Upper Cretaceous Nemegt Formation in the Gobi Desert, Mongolia: Contribution to depositional age constraints
6. ↑ I Know Dino: The Big Dinosaur Podcast, Episode 445: Dinosaurs in Swamps: Featuring Prehistoric Planet 2