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Bayan Mandahu Formation

geological formation in China

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionAug 4, 2026
Entity authorityQ4874284 ↗
Source-derived summary

The Bayan Mandahu Formation (also known as Wulansuhai Formation or Wuliangsuhai Formation) is a geological unit of "redbeds" located near the village of Bayan Mandahu in Inner Mongolia, China, in the Gobi Desert. It dates from the Late Cretaceous Period. Laid down in the Campanian, it is dated somewhat uncertainly to between 75 and 71 mya (million years ago).

Description

The paleoenvironment it preserves was semi-arid and characterized by alluvial (stream-deposited) and eolian (wind-deposited) sediments. The formation is known for its vertebrate fossils, most of which are preserved in unstructured sandstone, indicating burial by wind-blown sandstorms.

Paleofauna of the Bayan Mandahu Formation

The fauna of the Bayan Mandahu is very similar in composition to the nearby Djadochta Formation, and the two may have been deposited at roughly the same time. These two formations share many of the same genera, but differ in the makeup of species. For example, the most common mammal in the Djadochta is Kryptobaatar dashzevegi, while in the Bayan Mandahu, it is the closely related Kryptobaatar mandahuensis. Similarly, the dinosaur fauna of the Djadochta includes Protoceratops andrewsi and Velociraptor mongoliensis, while the Bayan Mandahu contains Protoceratops hellenikorhinus and Velociraptor osmolskae.

Crocodylomorphs

Lizards

An amphisbaenian species is known from the formation.

Editorial summary

This brief starts where responsible research should: with the source description of “Bayan Mandahu Formation” as geological formation in China. Everything that follows is an evidence route, not borrowed authority.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current 203-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. The account is most persuasive where Bayan, Mandahu and Formation can be independently traced.
Editorial analysis

Why this record matters

The subject matters to the general reference register because the source frames it as geological formation in China. Its deeper value depends on whether names, dates, institutions and citations support that framing.

Evidence profile

Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Aug 4, 2026. The linked authority identifier is Q4874284. Authority coordinates are 41.750, 106.750. None of the 1 selected statements returned an explicit reference.

Critical limits

A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

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Source & attribution

This entry incorporates text from “Bayan Mandahu Formation” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.