Wessex Formation

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Wessex Formation
Stratigraphic range: Berriasian–Barremian
Exposure of the Wessex Formation west of Chilton Chine
TypeGeological formation
Unit ofWealden Group
Sub-unitsCoarse Quartz Grit (in Dorset)
UnderliesVectis Formation
OverliesDurlston Formation
Thicknessup to 1000 m near Swanage
Lithology
Primarymudstone
Othersandstone, ironstone & conglomerate
Location
RegionSouthern England
Country UK
ExtentDorset, Isle of Wight, offshore Wessex Basin
Type section
Named forWessex
Named byDaley and Stewart
LocationBacon Hole, Mupe Bay
Year defined1979

Exposure of the Wessex and Vectis Formations on the South Coast of the Isle of Wight, shown in turquoise, exposures in Dorset not shown.

The Wessex Formation is a fossil-rich English geological formation that dates from the Berriasian to Barremian stages of the Early Cretaceous. It forms part of the Wealden Group and underlies the younger Vectis Formation and overlies the Durlston Formation.[1] The dominant lithology of this unit is mudstone with some interbedded sandstones. It is part of the strata of the Wessex Basin, exposed in both the Isle of Purbeck and the Isle of Wight. While the Purbeck sections are largely barren of vertebrate remains, the Isle of Wight sections are well known for producing the richest and most diverse fauna in Early Cretaceous Europe.

Nomenclatural history[edit]

The Wessex Formation has historically alternately been called the "Variegated Marls and Sandstones", a name used by W. J. Arkell in his 1947 map of the Isle of Purbeck[2] as well as the "Wealden Marls" [3] It was given its current formal name by Daley and Stewart in 1979.[4]

Stratigraphy and lithology[edit]

Introduction[edit]

Position of the Wessex Formation within the Wessex Basin succession

The Wessex Formation forms part of the Wealden Group within the Wessex Basin, an area of subsidence since Permo-Triassic times. The basin is located along southern half of the Isle of Wight and Purbeck, extending offshore into the English Channel. The Wealden Group is also exposed significantly in the Weald Basin, which has a separate stratigraphic succession. The Wealden Group is not widely present elsewhere in Britain, as these areas were tectonic highs where little to no sediment deposition was taking place. The formation has limited exposure as it has been deeply buried beneath the subsequent Lower Greensand. Selbourne and Chalk Groups, as well as being very vulnerable to erosion. It has been exposed at the surface due to the creation of anticlinal structures as a distant effect of the formation of the Pyrenees as part of the Alpine Orogeny during the Paleogene.[5] The major source rocks for the sediments were from the Cornubian Massif to the west, an upland region roughly equivalent to the extent of Cornwall and Devon, with occasional large dropstones transported in tree roots being found in Wealden sediments over 100 kilometres from where they originated.[6]

The Wessex Formation in the Isle of Purbeck[edit]

The exposure in of the Wessex Formation in the Isle of Purbeck is largely confined to a thin belt on the south side of the Purbeck Ridge and is best exposed at Swanage,[7] Lulworth Cove[8] and Worbarrow Bay.[9] One notable persistent horizon within the Purbeck sections of the formation is the "Coarse Quartz Grit", an up to 6 metre thick sequence of conglomeratic ironstone, with many beds including numerous centimetre sized subangular to rounded pebbles predominantly of vein derived quartz, hence the name. This horizon is present throughout the Purbeck outcrops of the Wessex Formation.[9] The transition to the Vectis Formation at Swanage is obscured by a landslip.[10]

The Wessex Formation of the Isle of Wight[edit]

Wessex Formation mudstones
Wessex Formation mudstones

The Isle of Wight succession has two primary exposures, The major one being the several kilometre long section along the South West coastline around Brighstone Bay, and another smaller exposure on the South East coast near Yaverland. While the formation taken as a whole dates from the Berriasian to the Barremian, only the uppermost part of the formation is exposed on the Isle of Wight. With less than 200 metres of exposed composite stratigraphic thickness, and which dates from Hauterivian to Barremian.[11] A radiometric date has been obtained from the lower part of the succession, estimated to be 127.3 ± 2.7 million years ago.[12] This makes the formation coeval with upper portion of the Weald Clay in the Weald Basin. The primary lithology of the exposed portion of the formation on the Isle of Wight consists of featureless purple-red overbank mudstone, interbedded with sandstones. The environment of deposition was a floodplain within a narrow, east–west oriented valley.[13] The climate at the time of deposition is considered to be semi-arid, based on the presence of pedogenic calcrete nodules within the mudstones.[14] The "Pine Raft" horizon found near the base of the exposed portion of the formation includes calcitized conifer trunks up to metre in diameter and 2–3 metres long.[15]

a dinosaur footprint
Cast of a dinosaur footprint, Wessex Formation

Plant debris beds[edit]

Close up of L6 plant debris bed, showing charcoalised plant matter suspended in grey mudstone

A notable feature of the formation are the so-called "plant debris beds". These consist of a basal matrix supported conglomerate, grading upwards into grey mudstone with lignitic plant debris, including large trunk fragments of the extinct conifer Pseudofrenelopsis present in the upper portion. These were formed by sheet flood deposits induced by storms that filled pre-existing topographic lows like oxbow lakes and abandoned channels in the floodplain depositional environment.[16] The debris beds do not form a continuous horizon throughout the formation, but are laterally extensive over tens of metres. Many of the wood fragments in the debris beds are cemented together with large nodules of pyrite, suggesting depositional conditions were anoxic.[17] Most fossils within the formation are associated with the debris beds. Vertebrate fossils are mostly disarticulated individual bones and teeth, suggesting a long subaerial exposure prior to burial, though the bones lack abrasion, suggesting that they had not been significantly transported. Partial skeletons also sometimes occur, but are uncommon. Autochthonous siderite nodules are also present, which encase some of the fossils.[16] Plant debris beds also exist within the Swanage section, and one of these horizons has yielded microvertebrate remains.[10]

"Hypsilophodon bed"[edit]

Skeleton of Hypsilophodon

While most fossils are associated with the plant debris beds, a notable exception is the "Hypsilophodon bed" present near the top of the formation, an up to 1 metre thick bed of silty red-green mudstone, with two separate horizons that have produced almost exclusively over a hundred complete and articulated skeletons of the dinosaur Hypsilophodon, sometimes even with preserved tail tendons. The bed is laterally extensive, being persistent for over a kilometre. It has been recently suggested that the accumulation of skeletons were a mass mortality event caused by a crevasse splay. Just above the "Hypsilophodon bed" the red mudstones of the Wessex Formation change to the transitional light coloured sandstone "White rock" and overlying laminated grey mudstones of the Vectis Formation, caused by the changing of environmental conditions from that of a floodplain to coastal lagoon conditions.[18]

Palaeoenvironment[edit]

The palaeoenvironment of the Wessex Formation is considered to have been semi-arid, and has variously been compared to chaparral[13] or macchia[10] Mediterranean shrubland. The dominant trees were conifers of the extinct family Cheirolepidiaceae belonging to the genera Pseudofrenelopsis and Watsoniocladus, both of which have reduced xerophytic leaves adapted to arid conditions.[10] Tree cover is thought to have been thin, and concentrated near waterways.[19] The ground cover is thought to have consisted of xerophytic ferns.[10] Wildfires were common occurrences, as evidenced by preserved charred vegetation.[16]

Fauna[edit]

Life restoration of dinosaurs discovered in Wessex Formation

Invertebrates[edit]

Invertebrates are commonly preserved in the Wessex Formation. Freshwater bivalves can be found including unionids such as Margaritifera, Nippononaia, and Unio. These bivalves help reconstruct what the freshwater paleoenvironment may have been like during the formation's deposition. Specimens of Viviparus, a genus of freshwater snail, have also been found. While compression fossils of insects are found in the overlying Vectis Formation, all insect fossils in the Wessex Formation are found as inclusions in amber. Amber can be found present as a rare component in plant debris beds in the Wessex formation both on the Isle of Wight and the Isle of Purbeck, however, the only significant concentration and where all of the inclusions have been found is a lag channel in the L6 plant debris horizon just south-east of Chilton Chine. Only four species from the amber have been formally described, Cretamygale chasei a mygalomorph spider, Dungeyella gavini[20] Libanodiamesa simpsoni, both chironomid midges, as well as Embolemopsis maryannae, a embolemid parasitic wasp. However a table of undescribed taxa has been given,[20] and several images of some of the undescribed taxa have been released from various sources, including multiple chironomids, and a therevid dipteran.[21]

Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Arthropods[edit]

Arthropods of the Wessex Formation
Genus Species Location Stratigraphic Position Abundance Note Images
Cypridea[22] C. wicheri, C. brevirostrata Dungy Head Base of the formation An ostracod belonging to Cypridoidea

Cretamygale

C. chasei[23]

Chilton Chine L6 plant debris bed Single specimen Mygalomorph spider, has been described from a specimen found in amber. See article
Dungeyella D. gavini[24] Chilton Chine L6 plant debris bed Multiple specimens A tiny buchonomyiine chironomid midge See article
Embolemopsis E. maryannae[25] Chilton Chine L6 plant debris bed Single specimen Embolemid parasitic wasp, genus also known from the Zaza Formation. Specimen previously described as a dryinid in a 2015 conference abstract.[21]
Protopangu P. valdensis[26] Chilton Chine L6 plant debris bed Single specimen A panguid parasitic stinging wasp
Libanodiamesa L. simpsoni[27] Chilton Chine L6 plant debris bed Single specimen Prodiamesinae chironomid, genus also known from the Lebanese amber
Chironomidae

Indeterminate

Chilton Chine L6 plant debris bed 44% of all arthropod inclusions Uncertain how many taxa represented, likely at least two. At least one is a tanypodian with a wingspan twice that of Dungeyella.
Therevidae Indeterminate Chilton Chine L6 plant debris bed At least one specimen At least one specimen figured
Diptera Indeterminate Chilton Chine L6 plant debris bed Multiple specimens Uncertain how many taxa represented
Hymenoptera

Indeterminate

Chilton Chine L6 plant debris bed Multiple specimens Uncertain how many taxa represented
Blattodea

Indeterminate

Chilton Chine L6 plant debris bed Single specimen
Coleoptera

Indeterminate

Chilton Chine L6 plant debris bed Single specimen
Curculionoidea?

Indeterminate

Represented by a boring in a gymnospermous seed.[28]

Cartilaginous fishes[edit]

Cartilaginous fishes of the Wessex Formation[29]
Genus Species Location Stratigraphic Position Abundance Note Images

Egertonodus

H. basanus

Hybodontid hybodont shark
Hybodus

Indeterminate 1

Yaverland bed 38, L9

Indeterminate 2

Yaverland bed 38, L9

Indeterminate 3

Yaverland bed 38, L9

Lonchidion

L. breve

Yaverland bed 38

Lonchidiid hybodont shark

L. striatum

Yaverland bed 38, L9

51.43% of total chondrichthyan taxa in L9

Indeterminate 1

Yaverland bed 38, L9

Indeterminate 2

Yaverland bed 38, L9

35.86% of total chondrichthyan taxa in Yaverland bed 38

Indeterminate 3

Yaverland bed 38, L9

Hylaeobatis

H. problematica

Palaeoscyllium

Indeterminate

Catshark

Parvodus

P. heterodon

Lonchidiid hybodont shark

Protospinax

Indeterminate

Selachimorph shark

Vectiselachos

V. ornatus

Lonchidiid hybodont shark

Ray-finned fish[edit]

Ray-finned fishes of the Wessex Formation[29]
Genus Species Location Stratigraphic Position Abundance Notes Images

Belonostomus

Indeterminate

Aspidorhynchiformes Known from isolated teeth
Full skeleton of the related Belonostomus tenuirostris

Caturus

Indeterminate

Amiiform fish

Coelodus

Indeterminate

Pycnodontid fish

Coccolepis[30]

Indeterminate

Coccolepidid fish

Lepidotes

Indeterminate

Ocloedus

Indeterminate

Pachythrissops

Indeterminate

Pycnodontiformes

Indeterminate

Scheenstia

Indeterminate

Lepidotid fish

Lissamphibians[edit]

Amphibians of the Wessex Formation
Genus Species Location Stratigraphic Position Abundance Notes Images
Wesserpeton[31] W.evansae L2 and Yaverland 38 Albanerpetontid amphibian

Anura[32]

Indeterminate

Multiple 1: Yaverland 38 2: L2 and Yaverland 38 3: L2 and Yaverland 38 4: Yaverland 38 5: Yaverland 38 At least 5 distinct taxa distinguished by characters in their ilium
Urodela Indeterminate Multiple 1: L2, L14 and Yaverland 33 and 38 2: L9 and Yaverland 38 3: unnamed bed in Compton bay and Yaverland 38 At least 3 distinct taxa distinguished by their atlas vertebrae

Squamates[edit]

Squamates of the Wessex Formation
Genus Species Location Stratigraphic Position Abundance Notes Images
Meyasaurus[31] Indeterminate Yaverland Yaverland bed 38 Teeth and a partial lower jaw Genus also known from Spain
Anguimorpha[32]

indeterminate

Multiple plant debris beds 1st taxon L14 and L2, 2nd L2 and Yaverland bed 38, 3rd Yaverland bed 38 At least 3 distinct taxa represented by isolated teeth, maxilla and lower jaw fragments, alongside a possible fourth taxon.[33]
Scincomorpha[32]

indeterminate

Multiple plant debris beds 1: L14 and Yaverland 38 2: Yaverland 38, 3: L2 and Yaverland 38 4,5: Yaverland bed 38 6:L2, L14 and Yaverland 38 7,8,9: Yaverland 38 10: L2, L14 and Yaverland 38 At least 10 distinct taxa represented by isolated teeth, maxilla and lower jaw fragments, some of which are paramacellodids based on the common occurrence of osteoderms typical of this clade.[33]

Turtles[edit]

Turtles of the Wessex Formation
Genus Species Location Stratigraphic Position Material Notes Images

Helochelydra

H. nopcsai

Shell and skull material Helochelydrid

Brodiechelys

B. brodiei

Shell fragments Xinjiangchelyid, previously known by the synonyms Plesiochelys brodiei Lydekker, 1889; Plesiochelys valdensis Lydekker, 1889 and Plesiochelys vectensis Hooley, 1900[34]
Eodortoka[12] E. cf. morellana Partial shell with associated vertebrae and limb bones A dortokid panpleurodiran turtle.

Neosuchians[edit]

Neosuchians of the Wessex Formation
Genus Species Location Stratigraphic Position Abundance Notes Images

Anteophthalmosuchus[35]

A. hooleyi

Disputed, either uppermost Wessex or lowermost Vectis

A. epikrator[36] Hanover Point Mostly complete skull and partial dentaries and associated postcranial material
Bernissartia Indeterminate 40 Isolated teeth

Hulkepholis

H. willetti

Koumpiodontosuchus[37]

K. aprosdokiti[37]

Theriosuchus

Indeterminate

Vectisuchus V. leptognathus Barnes High Just below base of Vectis formation "Partial semi-articulated skeleton"

Plesiosaurs[edit]

Plesiosaurs of the Wessex Formation
Genus Species Location Stratigraphic Position Abundance Notes Images

Elasmosauridae[38]

Indeterminate

Compton Bay

Vertebra

Plesiosauroidea[38]

Indeterminate

Tie pits, atherfield

Propodial

Leptocleididae?

Mammals[edit]

Mammals of the Wessex Formation
Genus Species Location Stratigraphic Position Material Notes Images

Eobaatar

E. clemensi[39]

Multiple debris beds L9, Yaverland bed 38 and CL3

Teeth

Eobaatarid multituberculate
?Gobiconodon Indeterminate Yaverland Yaverland bed 38 A lower right premolariform[40] Gobiconodontid

Loxaulax

?L. valdensis[39]

Teeth

Eobaatarid multituberculate

Yaverlestes[41]

Y. gassoni

Multiple debris beds Mandible from Yaverland bed 38, isolated teeth from L2, L9 and L14

Mandible Fragment and isolated teeth

Spalacotheriid

Dryolestidae[32]

Indeterminate

Multiple debris beds Yaverland bed 38 and L9 A lower right molar (NHMUK.M45558) C, an upper left molar (NHMUK.M45564)., a tentatively referred lower left or upper right premolar (NHMUK.M45484)[40]
Eutriconodonta Indeterminate Yaverland Yaverland bed 38 Lower left molariform

Zatheria[32]

Indeterminate

Premolars

Eutheria?

Pterosaurs[edit]

Pterosaurs of the Wessex Formation
Genus Species Location Stratigraphic Position Material Notes Images

Caulkicephalus

C. trimicrodon

Skull and rostrum fragments

An ornithocheirid

Ctenochasmatidae

Indeterminate

Tooth, potentially a gnathosaurine

Istiodactylus

I. latidens

Partial skeleton and skull, and referred mandible fragment

An istiodactylid

Istiodactylidae

Indeterminate

Found throughout the sub basin

Teeth

Two other species, distinct from I.latidens

Neoazhdarchia

Indeterminate

Humerus

Ornithocheiridae Indeterminate "partial distal left metacarpal IV"[42] Estimated wingspan of 5.6 metres

Uktenadactylus

U. rodriguesae

Rostrum fragment

An ornithocheirid, distinct from Coloborhynchus

Wightia[43]

W. declivirotris

Rostrum fragment

A tapejarid

Dinosaurs[edit]

Ornithischians[edit]

Ankylosaurs[edit]
Ankylosaurs reported from the Wessex Formation
Genus Species Synonyms Stratigraphic Position Material Notes Images
Polacanthus P. foxii

Polacanthoides ponderosus?

Dorsal vertebrae, dorsosacral vertebrae, sacral vertebrae, caudosacral vertebra, caudal vertebrae, dorsal ribs, ilia, pubes, ischia, femora, tibia, distal end of fibula, astragalus, metatarsals, ungual phalanx, sacral shield and osteoderms. An ankylosaur

Vectipelta V. barretti Partial skeleton An ankylosaur. Referred to as the "Spearpoint ankylosaur" prior to its original description. Only distantly related to Polacanthus.

Neornithischians[edit]
Neornithischians reported from the Wessex Formation
Genus Species Synonyms Stratigraphic Position Material Notes Images
Brighstoneus B. simmondsi Partial skeleton[44] A hadrosauriform iguanodontian

Hypsilophodon

H. foxii

Hypsilophodon bed Many partial skeletons A hypsolophodontid

Heterodontosauridae?

Indeterminate

Teeth Resemble the cheek teeth of the heterodontosaurid Tianyulong.[33]

Iguanodon

I. bernissartensis

A hadrosauroid iguanodontian. Specimens classified as Iguanodon seelyi are referable to this species

Mantellisaurus

M. atherfieldensis

Dollodon bampingi, Proplanicoxa?[45]

A hadrosauroid iguanodontian

Valdosaurus

V. canaliculatus

Multiple partial skeletons A dryosaurid

Vectidromeus[46] V. insularis Lower part of the formation Associated elements of the dorsal vertebrae, pelvis, hindlimbs, and tail, from a juvenile specimen A hypsilophodontid

Saurischians[edit]

Sauropods[edit]
Sauropods reported from the Wessex Formation
Genus Species Location Stratigraphic Position Material Notes Images

Chondrosteosaurus

C. gigas

"Several cervical vertebrae."[47]

Eucamerotus

E. foxi

"Dorsal vertebra."[47]

Perhaps a somphospondylan?[48]

Iuticosaurus

I. valdensis

"Several caudal vertebrae."[47]

Oplosaurus

O. armatus

"Tooth."[49]

Ornithopsis

O. eucamerotus

"Ischia and pubis.",[47] regarded as an "undiagnostic titanosauriform of uncertain affinities."

O. hulkei

One dorsal vertebra.[50]

Undescribed Sauropod (Barnes High sauropod) Indeterminate "Partial postcranial skeleton, including presacral vertebrae, anterior caudal vertebrae, girdle and limb elements"[51] Currently in private collection and unavailable to researchers. Known informally as "the Barnes High sauropod". Possibly the same as Eucamerotus[51]
"Angloposeidon" (informal) Indeterminate One cervical vertebra and possible associated centrum[52] Represents a large animal 20 metres or greater in length. Known informally as "Angloposeidon". Perhaps a somphospondylan?

Rebbachisauridae

Indeterminate

Scapula, radius and ulna, several cervical sacral and caudal vertebrae and isolated teeth from multiple individuals[53]

Taxon has close affinities with Demandasaurus and Nigersaurus[54]

Titanosauria

Indeterminate

Two isolated large middle caudal vertebra, one isolated large cervical vertebra, BMNH R5333, two articulated caudal vertebrae with an articulated fragment of a third

Theropods[edit]
Theropods reported from the Wessex Formation
Genus Species Location Stratigraphic Position Material Notes Images

Avialae

Indeterminate

Isolated teeth

Possibly an Enantiornithe and a Hesperornithid present

Aristosuchus

A. pusillus

"Sacrum and pubis."[55]

A compsognathid

Calamosaurus

C. foxi

"Vertebrae."[56]

A compsognathid

Calamospondylus

C. oweni

"Vertebrae."[56]

A possible oviraptorosaur

Ceratosuchops

C. inferodios

Partial skull material[57]

A spinosaurid, formerly considered remains of Baryonyx.

Eotyrannus

E. lengi

"Partial skull and skeleton."[58]

A tyrannosauroid

Neovenator

N. salerii

Cranial and postcranial remains of at least four individuals.

A carcharodontosaurian

Ornithodesmus

O. cluniculus

A species of dromaeosaurid, once misidentified as a pterosaur

Richardoestesia?

Indeterminate

Teeth

Dubious, uncertain referral on the genus level

Riparovenator

R. milnerae

Partial skull and referred caudal material[57]

A spinosaurid, formerly considered remains of Baryonyx.

Tetanurae Indeterminate Chilton Chine Partial pubis and femur[59] Distinct from Neovenator and Baryonyx. Currently in private collection.

Thecocoelurus

T. daviesi

"Cervical vertebrae."[60]

A theropod of uncertain classification, possibly an ornithomimosaur (this assignment has been questioned by both Mortimer and Naish).[61][62]

Undescribed coelurosaur Indeterminate Partial associated skeleton Apparently small. In private collection and undescribed. Referred to as "That Which Cannot Be Named" by Darren Naish[61] Has been suggested to be a tyrannosauroid.[63][33]
Coelurosauria

(Calamospondylus?)

Indeterminate (or possibly C. oweni) Tibia Previously referred to Hypsilophodon, Aristosuchus, Calamosaurus, Ornithomimosauria indet. and Coelurosauria indet.

Velociraptorinae

Indeterminate

Isolated teeth

May belong to a proceratosaurid,[64] or alternatively they may belong to Vectiraptor.

Vectiraptor

V. greeni

Dorsal vertebrae and sacral vertebrae

A large bodied Eudromaeosaur

Yaverlandia

Y. bitholus

Yaverland Known from a "partial skull roof comprising both frontals and parts of the right postorbital and left orbitosphenoid". A second specimen is known but has not been formally published.

A maniraptoran of uncertain classification, originally identified as an ornithischian.

Flora[edit]

Spermatophytes[edit]

Spermatophytes reported from the Wessex Formation
Family Genus Species Stratigraphic Position Material Notes Images
Araucariaceae Agathoxylon? Indeterminate Wood Reported as "Dadoxylon"

Considered a dubious referral[citation needed]

Araucariaceae Brachyphyllum B. obesum Leaves
Cheirolepidiaceae Pseudofrenelopsis P. parceramosa Leaves and abundant, occasional segments of trunk
Cheirolepidiaceae Watsoniocladus W. valdensis Leaves
Cupressaceae Sphenolepis Leaves "taxodiaceous"
Pinaceae Pityites P. solmsii

Pteridophytes[edit]

Pteridophytes reported from the Wessex Formation
Genus Species Location Stratigraphic Position Material Notes Images

Polypodiopsida

Indeterminate

Tempskya

Indeterminate

May actually originate from the underlying Purbeck Group.[10]

Weichselia

W. reticulata

Multiple specimens

See also[edit]

References[edit]

  1. ^ "Wessex Formation". The BGS Lexicon of Named Rock Units. British Geological Survey.
  2. ^ Arkell, W. J. (1947). "The Geology of the country around Weymouth, Swanage, Corfe and Lulworth". Memoir of the Geological Survey of Great Britain.
  3. ^ Osbourne White, H. J. (1921). "A short account of the geology of the Isle of Wight". Memoir of the Geological Survey of Great Britain.
  4. ^ Daley, B.; Stewart, D. J. (1979). "Weekend field meeting: The Wealden Group in the Isle of Wight". Proceedings of the Geologists' Association. 90: 51–54. doi:10.1016/S0016-7878(79)80031-0.
  5. ^ Parrish, Randall R.; Parrish, Claire M.; Lasalle, Stephanie (May 2018). "Vein calcite dating reveals Pyrenean orogen as cause of Paleogene deformation in southern England". Journal of the Geological Society. 175 (3): 425–442. Bibcode:2018JGSoc.175..425P. doi:10.1144/jgs2017-107. ISSN 0016-7649. S2CID 134690307.
  6. ^ Sweetman, Steven C.; Goodyear, Matthew (August 2020). "A remarkable dropstone from the Wessex Formation (Lower Cretaceous, Barremian) of the Isle of Wight, southern England". Proceedings of the Geologists' Association. 131 (3–4): 301–308. doi:10.1016/j.pgeola.2019.06.005. S2CID 198408317.
  7. ^ West, Ian. "Swanage Bay and Ballard Cliff". Geology of the Wessex Coast of Southern England.
  8. ^ West, Ian. "Lulworth Cove, Dorset". Geology of the Wessex Coast of Southern England.
  9. ^ a b West, Ian. "Worbarrow Bay". Geology of the Wessex Coast of England.
  10. ^ a b c d e f Penn, Simon J.; Sweetman, Steven C.; Martill, David M.; Coram, Robert A. (November 2020). "The Wessex Formation (Wealden Group, Lower Cretaceous) of Swanage Bay, southern England". Proceedings of the Geologists' Association. 131 (6): 679–698. doi:10.1016/j.pgeola.2020.07.005. S2CID 228820795.
  11. ^ Hughes, N.F.; McDougall, A.B. (January 1990). "New Wealden correlation for the Wessex Basin". Proceedings of the Geologists' Association. 101 (1): 85–90. doi:10.1016/S0016-7878(08)80208-8.
  12. ^ a b Jacobs, M. L.; Pérez-García, A.; Martín-Jiménez, M.; Mottram, C. M.; Martill, D. M.; Gale, A. S.; Mattsson, O.; Wood, C. (2023). "A well preserved pan-pleurodiran (Dortokidae) turtle from the English Lower Cretaceous and the first radiometric date for the Wessex Formation (Hauterivian-Barremian) of the Isle of Wight, United Kingdom". Cretaceous Research. 150. 105590. doi:10.1016/j.cretres.2023.105590.
  13. ^ a b Insole, Allan N.; Hutt, Stephen (September 1994). "The palaeoecology of the dinosaurs of the Wessex Formation (Wealden Group, Early Cretaceous), Isle of Wight, Southern England". Zoological Journal of the Linnean Society. 112 (1–2): 197–215. doi:10.1111/j.1096-3642.1994.tb00318.x.
  14. ^ Robinson, Stuart A.; Andrews, Julian E.; Hesselbo, Stephen P.; Radley, Jonathan D.; Dennis, Paul F.; Harding, Ian C.; Allen, Perce (March 2002). "Atmospheric pCO 2 and depositional environment from stable-isotope geochemistry of calcrete nodules (Barremian, Lower Cretaceous, Wealden Beds, England)". Journal of the Geological Society. 159 (2): 215–224. Bibcode:2002JGSoc.159..215R. doi:10.1144/0016-764901-015. ISSN 0016-7649. S2CID 55188160.
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External links[edit]

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