| Wonthaggi Formation | |
|---|---|
| Stratigraphic range: Valanginian–Barremian
| |
Flat rocks locality
| |
| Type | Geological formation |
| Unit of | Strzelecki Group |
| Underlies | Unconformity with Wombat Volcanics & Kersop Arkose |
| Overlies | Paleozoic basement |
| Thickness | Up to 2,500 m (8,200 ft) |
| Lithology | |
| Primary | Volcaniclastic sandstone, siltstone |
| Other | Conglomerate, coal |
| Location | |
| Coordinates | 38°42′S 145°42′E / 38.7°S 145.7°E / -38.7; 145.7 |
| Approximate paleocoordinates | 77°00′S 117°30′E / 77.0°S 117.5°E / -77.0; 117.5 |
| Region |  Victoria |
| Country |  Australia |
| Extent | Gippsland Basin |
 Exposure of Wonthaggi Formation green in bottom-right | |
The Wonthaggi Formation is an informal geological formation in Victoria, Australia whose strata date back to the Early Cretaceous. It is part of the Strzelecki Group within the Gippsland Basin. Dinosaur remains are among the fossils that have been recovered from the formation.[1][2] It is partially equivalent to the Eumeralla Formation.
The Wonthaggi Formation was deposited within the extensional rift valley formed between Australia and Antarctica. The lithology primarily consists of fluvially deposited siliciclastics derived from volcanic rocks of the Whitsunday Silicic Large Igneous Province to the East, with suggestions that the sediments either originated from braided river and sheet flood deposits, or meandering river systems on vegetated floodplains.[3] The age of the formation is thought to be ValanginiantoBarremian, with the Flat Rocks site being late Barremian (~125 Ma) in age, older than the sediments from the Eumeralla Formation, which are thought to be Aptian-Albian in age.
Indeterminate ornithopod remains are present in Victoria, Australia.[3] Indeterminate megaraptorid remains are present in Victoria, Australia.[4]
| Dinosaurs of the Wonthaggi Formation | ||||
|---|---|---|---|---|
| Genus | Species | Locality | Notes | Images |
|
cf. A. loadsi[3] |
Flat Rocks |
  | ||
|
F. australe[1] |
Considered a nomen dubium.[3] | |||
|
G. dorisae[3] |
Flat Rocks |
Known from a maxilla | ||
|
Q. intrepidus[1] |
Flat Rocks |
"[Three] dentaries and teeth."[5] | ||
|
S. arthurclarkei[1] |
The Arch, Kilcunda |
|||
|
Indeterminate |
Possibly also present at the Eumeralla Formation (footprints). |
Single furcula. | ||
| Ankylosauria[7] | Indeterminate | Flat Rocks | Teeth, dorsal vertebra, ribs, osteoderms | |
| Noasauridae[8] | Indeterminate | San Remo Member | NMV P221202, astragalocalcaneum | |
| Ornithopoda[3] | Indeterminate | Flat Rocks | Dentaries referred to as "Victorian ornithopodan dentary morphotype 3" including P228408, NMV P231182, NMV P199135 and isolated teeth | |
| Theropoda | Indeterminate | Eagles Nest | May represent a megaraptoran. Previously referred to Allosaurussp.. | |
| Amphibians of the Wonthaggi Formation | ||||
|---|---|---|---|---|
| Genus | Species | Presence | Notes | Images |
| Koolasuchus | K. cleelandi | Tree Trunk Point, Dwyers Hill, San Remo | Chigutisaurid temnospondyl, last known temnospondyl |  |
| Mammals of the Wonthaggi Formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Ausktribosphenos | A. nyktos | Flat rocks | Partial dentary with teeth | Ausktribosphenid | |
| Bishops | B. whitmorei | Partial dentary with teeth | Ausktribosphenid | ||
| Corriebaatar | C. marywaltersae | "NMV P216655, a fragment of a left dentary bearing a complete plagiaulacoid p4 and the anterior root of m1" | Multituberculate |  | |
| Kryoparvus | K. gerriti | Partial dentary with teeth | ?Ausktribosphenid | ||
| Teinolophos | T. trusleri | Partial dentary with teeth | Monotreme | ||
