The lithology of the sediment largely consists of cross bedded sandstones with interbeds of massive sandstone, well cemented intraformational conglomerate, siltstones and mudstones. Most of the fossils are found as clasts within the conglomerates.[2]
Fossil content
The Bissekty Formation is characterised by a mix of marine, brackish, freshwater, and terrestrialanimal fossils. This stands in contrast the strictly marine fossils found in the underlying Dzheirantui Formation, and indicates that the Bissekty was formed during the regression of a saltwater sea. The coastline expanded inland again in the upper portion of the Bissekty, represented by a proportional increase of fully aquatic species, which were almost completely absent from the middle period of the formation. Semi-aquatic species remained abundant during this middle period, and the geology of the formations indicates that a braided river system took the place of the coastline. Eventually the area was again completely underwater, during the time period represented by the later Aitym Formation, which preserves coastal marine sediments.[2]
Vertebrates
The Bissekty Formation is notable for preserving the most abundant Turonian land animal fossils in Eurasia, and the most diverse fauna of Late Cretaceous eutherians (placental mammals and relatives) in the world.[2]
Listings and accompanying information are based on a survey of the Bissekty Formation published by Cory Redman and Lindsey Leighton in 2009 unless otherwise noted.[2] Aquatic and semi-aquatic species are restricted to freshwater unless otherwise noted.
Amphibians
An indeterminate species of salamander-like albanerpetontid amphibian. An indeterminate gobiatid species.
An indeterminate acipenserid. An indeterminate albulid (bonefish) species. An indeterminate albulid (bonefish) species. An indeterminate pholidophoriform species.
An indeterminate species of marine placenticeratid ammonite. An indeterminate species of marine teredinid shipworm. An indeterminate marine trigoniid bivalve. An indeterminate marine veneroid bivalve.
^Grande, G; Bemis, E (2014). "A comprehensive phylogenetic study of amiid fishes (Amiidae) based on comparative skeletal anatomy. An empirical search for interconnected patterns of natural history. (project)". MorphoBank datasets. doi:10.7934/p482.
^Archibald, James David; Sues, Hans-Dieter; Averianov, Alexander; King, Chris; Ward, David John; Tsaruk, Oleg; Danilov, Igor; Rezvyi, Anton; Veretennikov, Boris; Khodjaev, Anvar (1998). "Precis of the Cretaceous paleontology, biostratigtaphy and sedimentology at Dzharakuduk (Turonian?-Santonian), Kyzylkum Desert, Uzbekistan". Bulletin of the New Mexico Museum of Natural History and Science. 14: 21–27.
^"Table 6.1," in Weishampel, et al. (2004). Page 139.
^"Table 8.1," in Weishampel, et al. (2004). Page 166.
^"Table 10.1," in Weishampel, et al. (2004). Page 199.
^"Table 9.1," in Weishampel, et al. (2004). Page 185.
^Nesov, A. (1995). "Dinosaurs of Northern Eurasia: new data about assemblages, ecology and paleobiogeography." Scientific Research Institute of the Earth's Crust. St. Petersburg State University, St. Petersburg, Russia: 156 pp. + 14 pl. [in Russian with short English, German, and French abstracts].
^ abcd"Table 11.1," in Weishampel, et al. (2004). Page 212.
^ abcdefghijklmno"Dinosaur distribution (Bissekty Formation)." Weishampel, et al. (2004). Pg. 594.
^ ab"Table 11.1," in Weishampel, et al. (2004). Page 216.
^Averianov, A.O.; Sues, H.-D. (2007). "A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union". Journal of Vertebrate Paleontology. 27 (1): 87–98. doi:10.1671/0272-4634(2007)27[87:ANTDTF]2.0.CO;2. S2CID9743271.
^ abcdefghPanteleev (1998). ""New species of enantiornithines (Aves: Enantiornithes) from the Upper Cretaceous of Central Kyzylkum." Russkii Ornitologicheskii Zhurnal". Ekspress-vy.PVSK. 35: 3–15.
^ abc"Table 11.1," in Weishampel, et al. (2004). Page 213.
^Kurochkin. (1996). "A new Enantiornithid of the Mongolian Late Cretaceous, and a general appraisal of the Infraclass Enantiornithes (Aves)." Russian Academy of Sciences, special issue: 50pp.
^ abc"Table 11.1," in Weishampel, et al. (2004). Page 214.
Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (2004), The Dinosauria, 2nd edition, Berkeley: University of California Press, pp. 1–880, ISBN0-520-24209-2, retrieved 2019-02-21
Storrs, G.W.; Efimov, M.B. (2000), Mesozoic crocodyliforms of north-central Eurasia, In M. J. Benton, M. A. Shishkin, D. M. Unwin, E. N. Kurochkin (eds.), The Age of Dinosaurs in Russia and Mongolia, pp. 402–419, retrieved 2019-03-22