Madygen Formation

Madygen Formation
Stratigraphic range: Carnian
~235–222 Ma
TypeGeological formation
OverliesCambrian to Carboniferous rocks
Thickness560 m (1,840 ft)
Lithology
PrimaryConglomerate, sandstone
OtherMudstone
Location
Coordinates40°06′N 70°12′E / 40.1°N 70.2°E / 40.1; 70.2
Approximate paleocoordinates41°12′N 60°36′E / 41.2°N 60.6°E / 41.2; 60.6
RegionBatken & Osh Regions
CountryKyrgyzstan
Tajikistan
Uzbekistan
ExtentFergana Valley & Range
Type section
Named forMadygen village
Named byEvgeny A. Kochnev
Madygen Formation is located in Kyrgyzstan
Madygen Formation
Madygen Formation (Kyrgyzstan)

The Madygen Formation (Russian: Madygen Svita) is a MiddleLate Triassic (LadinianCarnian) geologic formation and lagerstätte in the Batken and Osh Regions of western Kyrgyzstan, with minor outcrops in neighboring Tajikistan and Uzbekistan. The conglomerates, sandstones and mudstones of the 560 m (1,840 ft) thick formation were deposited in terrestrial lacustrine, alluvial, fluvial and deltaic environments.[1]

The formation, extending across the Fergana Valley and Fergana Range, is unique for Central Asia, as it represents one of the few known continental deposits and the Madygen Formation is renowned for the preservation of more than 20,000 fossil insects, making it one of the richest Triassic lagerstätten in the world. Other vertebrate fossils as fish, amphibians, reptiles and synapsids have been recovered from the formation too, as well as minor fossil flora.

The lake sediments of the Lagerstätte provided fossil cartilaginous fishes and their egg capsules and unusual Triassic reptiles like Sharovipteryx and Longisquama.[2][3] The wide diversity of insect fossils was first discovered in the 1960s and first described by Russian paleontologist Aleksandr Sharov, with a notable example being Gigatitan.[4]

  1. ^ Sebastian Voigt, Michael Buchwitz, Jan Fischer, Ilja Kogan, Philippe Moisan, Jörg W. Schneider, Frederik Spindler, Andreas Brosig, Marvin Preusse, Frank Scholze and Ulf Linnemann (2018). "Chapter 3 Triassic life in an inland lake basin of the warm-temperate biome – the Madygen Lagerstätte (southwest Kyrgyzstan, Central Asia)". In Fraser, Nicholas C.; Sues, Hans-Dieter (eds.). Terrestrial Conservation Lagerstatten: Windows into the Evolution of Life on Land. Liverpool University Press. pp. 65–104. doi:10.2307/jj.12638994.6. ISBN 978-1-78046-583-8. JSTOR jj.12638994.{{cite book}}: CS1 maint: multiple names: authors list (link)
  2. ^ Fischer, Jan; Voigt, Sebastian; Schneider, Jörg W.; Buchwitz, Michael; Voigt, Silke (2011). "A selachian freshwater fauna from the Triassic of Kyrgyzstan and its implication for Mesozoic shark nurseries". Journal of Vertebrate Paleontology. 31 (5): 937–953. Bibcode:2011JVPal..31..937F. doi:10.1080/02724634.2011.601729. ISSN 0272-4634.
  3. ^ Unwin, David M.; Alifanov, Vladimir R.; Benton, Michael J. (2003). "Enigmatic small reptiles from the Middle-Late Triassic of Kirgizstan". In Benton, Michael J.; Shishkin, Mikhail A.; Unwin, David M.; Kurochkin, Evgenii M. (eds.). The Age of Dinosaurs in Russia and Mongolia. Cambridge: Cambridge University Press. pp. 177–186. ISBN 9780521545822.
  4. ^ Shcherbakov, Dmitry (2008). "Madygen, Triassic Lagerstätte number one, before and after Sharov" (PDF). Alavesia. 2: 113–124.