Jindong Formation

The Jindong Formation (Korean: 진동층; Hanja: 鎭東層; RR: Jindong-cheung) is a geological formation located in South Korea. It is dated to the Cenomanian stage of the Late Cretaceous, between 99.9 ± 0.7 Ma and 96 Ma.^[1][2]

Jindong Formation
Stratigraphic range: Cenomanian ~99.9–96 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Unit of	Hayang Group
Underlies	Yucheon Group (volcanics)
Overlies	Haman Formation
Lithology
Primary	Mudstone, siltstone
Other	Sandstone, shale
Location
Coordinates	35.4°N 128.4°E / 35.4; 128.4
Approximate paleocoordinates	44.7°N 122.9°E / 44.7; 122.9
Region	Gyeongsangnam-do
Country	South Korea
Extent	Gyeongsang Basin
Jindong Formation (South Korea)

Geological background

The Jindong Formation consists of thick, fine-grained, altered volcaniclastic sediments. Most of these sediments are ash-rich mudstone, siltstone, and very fine sandstone. There are also coarser sandstone, conglomerate, carbonates, and tuff. ^[3]

Paleontology

The Jindong Formation has yielded numerous of dinosaurs and bird tracks.^[4][5] Ichnofossils including unnamed tracks of sauropods^[6] and pterosaurs,^[7] the isolated sauropod skin impression not associated with trackways,^[8] and the poorly preserved juvenile sauropod trackway with no ichnotaxon assignment^[9] have been reported.

Ichnofossils of the Jindong Formation[10]
Ichnogenus	Ichnospecies	Region	Member	Material	Notes	Image
Brontopodus[5]	B. isp.				Sauropod tracks
Caririchnium[5]	C. isp.				Ornithopod tracks
Goseongornipes[5]	G. markjonesi				Bird tracks
Gyeongsangornipes[11]	G. lockleyi				Bird tracks
Hadrosauropodus	H. kyoungsookimi[12]				The first trackway of a quadrupedal ornithopod discovered in Korea, originally attributed to the ichnogenus Caririchnium.[13]
Jindongornipes[5]	J. kimi				Bird tracks
Koreanaornis[5]	K. hamanensis				Bird tracks
Ornithopodichnus[14]	O. masanensis				Currently regarded as dubious ichnotaxon made by ornithopod trackmakers.
Undichna[15]	U. simplicatis U. bina U. britannica				Fish swim traces

See also

• List of fossil sites