The expeditions were led by Roy Chapman Andrews, in company of Walter Willis Granger as chief paleontologist and field team.

The team did extensive exploration at the Bayn Dzak (formerly Shabarakh Usu) region, which they nicknamed flaming cliffs, given that at sunset the sediments of this locality had a characteristic reddish color.

[3] During the 1960s to 1970s, Polish-Mongolian and Russian-Mongolian paleontological expeditions collected new, partial to complete specimens of Protoceratops and Velociraptor at this locality, making these dinosaur species a common occurrence in Tugriken Shireh.

[4] In 1993 a collaborative expedition by the Mongolian Academy of Sciences and the American Museum of Natural History discovered a new fossil site within the Djadochta Formation, named Ukhaa Tolgod, which translates to "Brown Hills."

[9][10] The modern-day Djadochta Formation is set in an arid habitat of sand dunes with little freshwater apart from oases and arroyos, in the Gobi Desert.

The dominant lithology of the Djadochta Formation is represented by non-marine, cemented reddish-orange and pale orange to light gray, medium to fine-grained sands and sandstones, which include minor deposits of calcareous concretions and orange-brown silty clay.

Several aeolian processes (wind works) indicate the presence of large straight-crested dune-like structures, and smaller barchan (crescent-shaped) and parabolic (poorly U-shaped) dunes across the formation.

However, it is not yet understood the precise temporal difference:[12] Localities within the Djadochta Formation are considered to represent a sequence of progressively younger sediments and thereby paleofaunas.

[20][12][14] Fluvial sedimentation at the Ukhaa Tolgod locality indicates the presence of short-lived water bodies during the times of the formation, which also contributed to its deposition.

[10] A vast majority of articulated specimens from the Djadochta Formation are found in unstructured sandstones, indicating burial in situ by high-energy sand-bearing events.

It is thought to have occurred when sand dunes became oversaturated with water resulting in their sudden downfall; heavy rainfall events likely acted as the triggering mechanism for this collapse.

[9][25][10] Examples from the Ukhaa Tolgod preservation include Citipati (brooding adults entombed atop nests and eggs);[26][27] Khaan (a pair in close proximity likely killed by a single collapse event);[28] and Saichangurvel (individual buried alive by a muddy dune).

In contrast to Djadochta, Nemegt has yielded an extensive diversity of large dinosaur taxa, such as Deinocheirus, Nemegtosaurus, Saurolophus, Tarbosaurus, or Therizinosaurus.