Kallamedu Formation
Geologic formation in India
Kallamedu Formation | |
---|---|
Stratigraphic range: Maastrichtian ~70.6–65.5 Ma PreꞒ Ꞓ O S D C P T J K Pg N | |
Type | Geological formation |
Underlies | Niniyur Formation |
Overlies | Archean Basement |
Thickness | Variable, typically 5–5,000 km (3.1–3,106.9 mi) |
Lithology | |
Primary | Claystone, siltstone limestone |
Other | Conglomerate |
Location | |
Coordinates | 11°41′46″N 79°24′46″E / 11.6962°N 79.4127°E / 11.6962; 79.4127 |
Country | ![]() |
Extent | Kallamedu |
Type section | |
Named for | Kallamedu village |
The Kallamedu Formation is a Late Cretaceous (Maastrichtian) geologic formation located in the Ariyalur district of Tamil Nadu, India that forms part of the Ariyalur Group.[1] It dates to the Maastrichtian of the Late Cretaceous. Dinosaur remains and petrified wood samples are among the known fossils recovered from this formation.[2]
Lithology
The Kallamedu Formation likely represented a fluvial environment. It is composed of siltstones, clays and sandstones. The high organic carbon content of some of the rocks are consistent with a swamp.[3]
Paleofauna
Color key
| Notes Uncertain or tentative taxa are in small text; |
Dinosaurs
Dinosaurs from the Kallamedu Formation | ||||||
---|---|---|---|---|---|---|
Genus | Species | Material | Notes | |||
Abelisauridae indet.[4] | "Disassociated remains" and teeth. | |||||
Carnosauria indet.?[5] | "Fragmentary remains" | Carnosauria was often used as a wastebasket taxon. | ||||
Troodontidae indet.[4] | One isolated tooth (DUGF/52). | |||||
Bruhathkayosaurus[5][6] | B. matleyi | ilium and ischium, femur, tibia, radius and part of a vertebra (specifically a platycoelous caudal centrum). Remains no longer exist | Initially described as a Theropod, it was reclassified as a Titanosaur. | |||
Sauropoda | Indeterminate.[7][8] | "Fragmentary remains." | ||||
Titanosauria | Indeterminate.[9] | Solitary egg. | ||||
Titanosauria | Indeterminate.[10] | Ten large sauropod bones, some of which could be identified as a humerus or femur, proximal end of a femur and scapula. All the bones pertain to the limbs. | Similar in size to Bruhatkayosaurus.[6] | |||
Fusioolithus[9] | F. baghensis | Dinosaur eggs. | ||||
?Camarasauridae[11] | Indeterminate. | Vertebrae. | Camarasaurids are not known from the cretaceous. | |||
?Stegosauria[12] | Indeterminate. | Misinterpreted sauropod bone. | Other more plausible Stegosaur material is known from Cretaceous India. |
Crocodylomorphs
Crocodylomorphs from the Kallamedu Formation | ||||||
---|---|---|---|---|---|---|
Genus | Species | Material | Notes | |||
Crocodilia[13] | Indeterminate | Teeth. | ||||
Simosuchus [13] | cf. Simosuchus sp. | Teeth. | Notosuchian Related to Simosuchus. |
Turtles
Turtle from the Kallamedu Formation | ||||||
---|---|---|---|---|---|---|
Genus | Species | Material | Notes | |||
Kurmademys [14] | K. kallamedensis | Nearly complete skull. | A Side-necked Turtle. | |||
Testudines[13] | Indeterminate | Several fragmentary pieces of carapace and one vetebral element. | Too fragmentary to compare with Kurmademys. |
Fish
Fish from the Kallamedu Formation | ||||||
---|---|---|---|---|---|---|
Genus | Species | Material | Notes | |||
Lepisosteidae[13] | Indeterminate. | Scales. | Similar scales are known from the Intertrappean Beds. |
Amphibians
Amphibians from the Kallamedu Formation | ||||||
---|---|---|---|---|---|---|
Genus | Species | Material | Notes | |||
Anura[13] | Indeterminate. | Fragmentary ilium. |
References
- ^ Memoirs of the Geological Survey of India. Oxford University. 1865. pp. 107–140.
- ^ Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, Asia)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 593–600. ISBN 0-520-24209-2.
- ^ https://www.researchgate.net/publication/263426844_SEDIMENTOLOGICAL_STUDIES_OF_KALLAMEDU_FORMATION_IN_ARIYALUR_AREA_TAMIL_NADU_INDIA
- ^ a b Goswami, A.; Prasad, G. V. R.; Verma, O.; Flynn, J. J.; Benson, R. B. J. (2013). "A troodontid dinosaur from the latest Cretaceous of India". Nature Communications. 4: 1703. Bibcode:2013NatCo...4.1703G. doi:10.1038/ncomms2716. PMID 23591870.
- ^ a b Yadagiri, P. and Ayyasami, K. (1987). "A carnosaurian dinosaur from the Kallamedu Formation (Maestrichtian horizon), Tamilnadu." In M.V.A. Sastry, V.V. Sastry, C.G.K. Ramanujam, H.M. Kapoor, B.R. Jagannatha Rao, P.P. Satsangi, and U.B. Mathur (eds.), Three Decades of Development in Palaeontology and Stratigraphy in India. Volume 1. Precambrian to Mesozoic. Geological Society of India Special Publication, 11(1): 523–528.
- ^ a b Pal, Saurabh; Ayyasami, Krishnan (May 2022). "The lost titan of Cauvery". Geology Today. 38 (3): 112–116. doi:10.1111/gto.12390. ISSN 0266-6979.
- ^ R. Lydekker. (1877). Notices of new and other Vertebrata from Indian Tertiary and Secondary rocks. Records of the Geological Survey of India 10(1):30–43
- ^ C. R. Narayana Rao and L. Rama Rao. 1930. The limb bones of a sauropodous dinosaur. Proceedings of the Indian Science Congress, Allahabad 17:330.
- ^ a b Dhiman, Harsha; Prasad, Guntupalli V. R.; Goswami, Anjali (2018). "Parataxonomy and palaeobiogeographic significance of dinosaur eggshell fragments from the Upper Cretaceous strata of the Cauvery Basin, South India". Historical Biology: 1–13. doi:10.1080/08912963.2018.1450408. S2CID 89969203.
- ^ Matley, 1929. The Cretaceous Dinosaurs of the Trichinopoly district and the rocks associated with them. Rec. Geof. Surv. India. Vol. 61 (4):337-349.
- ^ C. R. Narayana Rao and L. Rama Rao. 1930. Some dinosaurian vertebrae. Proceedings of the Indian Science Congress, Allahabad 17:329.
- ^ Peter M. Galton; Krishnan Ayyasami (2017). "Purported latest bone of a plated dinosaur (Ornithischia: Stegosauria), a "dermal plate" from the Maastrichtian (Upper Cretaceous) of southern India". Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 285 (1): 91–96. doi:10.1127/njgpa/2017/0671.
- ^ a b c d e Prasad, G. V. R., Verma, O., Flynn, J. J. & Goswami, A. (2013) A new Late Cretaceous vertebrate fauna from the Cauvery basin, South India: implications for Gondwanan palaeobiogeography. Journal of Vertebrate Paleontology.
- ^ Gaffney, Eugene S; Chatterjee, Sankar; Rudra, Dhiraj K. (2001). "Kurmademys, a new side-necked turtle (Pelomedusoides: Bothremydidae) from the Late Cretaceous of India" (pdf). American Museum Novitates (3321): 1–16. doi:10.1206/0003-0082(2001)321<0001:kansnt>2.0.co;2. hdl:2246/2938. S2CID 53980146.