Madygen Formation
The Madygen Formation (Russian: Madygen Svita) is a Late Triassic (Carnian) 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.
| Madygen Formation | |
|---|---|
| Stratigraphic range: Carnian ~ | |
| Type | Geological formation |
| Overlies | Cambrian to Carboniferous rocks |
| Thickness | 560 m (1,840 ft) |
| Lithology | |
| Primary | Conglomerate, sandstone |
| Other | Mudstone |
| Location | |
| Coordinates | 40.1°N 70.2°E |
| Approximate paleocoordinates | 41.2°N 60.6°E |
| Region | Batken & Osh Regions |
| Country | Kyrgyzstan Tajikistan Uzbekistan |
| Extent | Fergana Valley & Range |
| Type section | |
| Named for | Madygen village |
| Named by | Evgeny A. Kochnev |
Madygen Formation (Kyrgyzstan) | |
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. 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.