| Lulworth Formation | |
|---|---|
| Stratigraphic range: Tithonian - Berriasian | |
![]() Lulworth Cove, an area where the Lulworth Formation is exposed | |
| Type | Formation |
| Unit of | Purbeck Group |
| Sub-units |
|
| Underlies | Durlston Formation |
| Overlies | Portland Stone Formation |
| Thickness | In Dorset 27-63 metres, In Weald 86 m Vale of Wardour up to 15m |
| Lithology | |
| Primary | Calcarenite, Micrite, Mudstone, Marl |
| Other | Gypsum |
| Location | |
| Region | England |
| Country | United Kingdom |
| Type section | |
| Named for | Lulworth |
| Location | West side of Worbarrow Tout |
The Lulworth Formation is a geologic formation in England. It dates from the late Tithonian to the mid Berriasian. It is a subunit of the Purbeck Group.[1] In Dorset, it consists of three members, which are in ascending order, the Mupe Member, the Ridgway Member, and the Warbarrow Tout Member. The Mupe Member is typically 11 to 16 m thick and largely consists of marls and micrites with interbeds of calcareous mudstone.[2] The Ridgeway Member is about 3 to 7 m thick and consists of in its western portion carbonaceous muds, marls and micrites, in the east the muds are replaced by micritic limestone.[3] The Warbarrow Tout Member is 17 to 39 m thick and consists of limestone at the base and micrite and mudstone for the rest of the sequence,[4] this member is the primary source of the vertebrate fossils within the formation.[5][6] Elsewhere the unit is undifferentiated.
Vertebrate paleobiota
Amphibians
| Amphibians reported from the Lulworth Formation[7] | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Apricosiren | A. ensomi | Worbarrow Tout Member | Salamander | |||
| Celtedens | C. megacephalus | Worbarrow Tout Member | Albanerpetontid | |||
| Sunnybatrachus | S. purbeckensis | Worbarrow Tout Member | Frog, affinites to Discoglossidae | |||
| ?Batrachosauroididae | Indeterminate | Worbarrow Tout Member | Salamander | |||
Turtles
| Turtles reported from the Lulworth Formation[8] | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Dorsetochelys | D. typocardium, D. delairi | Both species probably represent the same taxon[9] | ||||
| Helochelydra | H. anglica | |||||
| Hylaeochelys | H. latiscutata | |||||
| Pleurosternon | P. bullocki | |||||
Lepidosaurs
| Lepidosaurs reported from the Lulworth Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Becklesius | Indeterminate | |||||
| Dorsetisaurus | D. hebetidens, D. purbeckensis | |||||
| Durotrigia | D. triconidens | |||||
| Homoeosaurus | Indeterminate | Rhynchocephalian | ||||
| Opisthias | Indeterminate | Rhynchocephalian | ||||
| Paramacellodus | P. oweni | |||||
| Parasaurillus | P. pseudobtusus | |||||
| Parviraptor | P. estesi | Stem-snake | ||||
| Pseudosaurillus | P. becklesi | |||||
| Purbicella | P. ragei | |||||
| Saurillus | S. robustidens | |||||
Crocodyliformes
| Crocodyliformes reported from the Lulworth Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| cf. Bernissartia | Indeterminate | Teeth | ||||
| Goniopholis | Indeterminate | |||||
| Nannosuchus | N. gracilidens | |||||
| Theriosuchus | T. pusillus | |||||
Dinosaurs
| Dinosaurs reported from the Lulworth Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Echinodon | E. becklesii[10] | Durlston Bay, Swanage[10] | Teeth and dentary | A small heterodontosaurid | ||
| Owenodon | O. hoggii[11] | Durlston Bay, Swanage | Partial dentary | An iguanodontoid | ||
| Nuthetes | N. destructor[12] | Feather Quarry, Durlston Bay, Swanage | Teeth, dentary fragment | Small dromaeosaur | ||
Mammals
| Mammals reported from the Lulworth Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Albionbaatar | A. denisae | Sunnydown Farm Quarry | Albionbaataridae | |||
| Amblotherium | A. pusillum, A. soricinum, A. nanum | Mammal Bed | ||||
| Bolodon | B. minor, B. crassidens, B. osborni, B. elongatus, B. falconeri | Mammal Bed | Plagiaulacidae | |||
| Chunnelodon | C. alopekodes | Sunnydown Farm Quarry | ||||
| Ctenacodon | C. minor | Mammal Bed | Allodontidae | |||
| Dorsetodon | D. haysomi | Sunnydown Farm Quarry | Paurodontidae | |||
| Durlstotherium | D. newmani | Mammal Bed | ||||
| Durlstodon | D. ensomi | Mammal Bed | ||||
| Gerhardodon | G. purbeckensis | Sunnydown Farm Quarry | Pinheirodontidae | |||
| Kouriogenys | K. minor | Mammal Bed | Peramuridae | |||
| Magnimus | M. ensomi | Sunnydown Farm Quarry | ||||
| Peraiocynodon | P. inexpectatus | Mammal Bed | Docodontidae | |||
| Peramuroides | P. tenuiscus | Mammal Bed | Peramuridae | |||
| Peramus | P. tenuirostris, P. dubius, P. minor | Mammal Bed | Peramuridae | |||
| Peraspalax | P. talpoides | Mammal Bed, Sunnydown Farm Quarry | Dryolestidae | |||
| Phascolestes | P. mustelula | Mammal Bed, Sunnydown Farm Quarry | Dryolestidae | |||
| Plagiaulax | P. becklesii | Mammal Bed | Plagiaulacidae | |||
| Purbeckodon | P. batei | Sunnydown Farm Quarry | Morganucodonta | |||
| Spalacotherium | S. tricuspidens, S. evansae, S. hookeri | Mammal Bed, Sunnydown Farm Quarry | Spalacotheriidae | |||
| Sunnyodon | S. notleyi | Sunnydown Farm Quarry | Paulchoffatiidae | |||
| Thereuodon | T. taraktes | Sunnydown Farm Quarry | ||||
| Tinodon | T. micron | Sunnydown Farm Quarry | Tinodontidae | |||
| Triconodon | T. mordax | Mammal Bed, Sunnydown Farm Quarry | ||||
| Trioracodon | T. bisulcus, T. major, T. oweni | Mammal Bed, Feather Quarry | ||||
See also
References
- ↑ "Lulworth Formation". BGS Lexicon of Named Rock Units. British Geological Survey. Retrieved 28 August 2018.
- ↑ "Mupe Member". BGS Lexicon of Named Rock Units. British Geological Survey. Retrieved 28 August 2018.
- ↑ "Ridgeway Member". BGS Lexicon of Named Rock Units. British Geological Survey. Retrieved 28 August 2018.
- ↑ "Warbarrow Tout Member". BGS Lexicon of Named Rock Units. British Geological Survey. Retrieved 28 August 2018.
- ↑ "Sunnydown Farm Quarry (clay: upper horizon; equivalent to DB 102/103 )". Paleobiology Database. Retrieved 28 August 2018.
- ↑ "Mammal Bed, Durlston Bay (DB83)". Paleobiology Database. Retrieved 28 August 2018.
- ↑ Evans, Susan E.; McGowan, Gerard J. (2002). "Lissamphibian remains from the Purbeck Limestone Group, southern England". Special Papers in Palaeontology: 104–119.
- ↑ Milner, Andrew R. (November 2004). "The turtles of the Purbeck Limestone Group of Dorset, southern England" (PDF). Palaeontology. 47 (6): 1441–1467. doi:10.1111/j.0031-0239.2004.00418.x. ISSN 0031-0239.
- ↑ Pérez-García, A. (May 2014). "Revision of the poorly known Dorsetochelys typocardium, a relatively abundant pleurosternid turtle (Paracryptodira) in the Early Cretaceous of Europe". Cretaceous Research. 49: 152–162. doi:10.1016/j.cretres.2014.02.015. ISSN 0195-6671.
- 1 2 "Type specimen: BMNH 48209, 48210, a mandible. Its type locality is cliff face, Durlston Bay, which is in a Berriasian fluvial-lacustrine limestone in the Lulworth Formation of the United Kingdom". fossilworks.org.
- ↑ "Type specimen: BMNH R2998. Its type locality is Durlston Bay, Swanage (DB105-107), which is in a Berriasian marine limestone in the Lulworth Formation of the United Kingdom".
- ↑ "Type specimen: DORCM G913, a mandible. Its type locality is Feather Quarry, Durlston Bay (DB102), which is in a Berriasian marine shale in the Lulworth Formation of the United Kingdom".
