Fossil Forest, West Lulworth, Dorset - geograph

The Fossil Forest is the remains of an ancient submerged forest from

Jurassic The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...

times, located to the east of

Lulworth Cove Lulworth Cove is a cove near the village of West Lulworth, on the Jurassic Coast in Dorset, southern England. The cove is one of the world's finest examples of such a landform, and is a World Heritage Site and tourist location with approximately ...

on the

Isle of Purbeck The Isle of Purbeck is a peninsula in Dorset, England. It is bordered by water on three sides: the English Channel to the south and east, where steep cliffs fall to the sea; and by the marshy lands of the River Frome and Poole Harbour to the no ...

Dorset Dorset ( ; archaically: Dorsetshire , ) is a county in South West England on the English Channel coast. The ceremonial county comprises the unitary authority areas of Bournemouth, Christchurch and Poole and Dorset. Covering an area of , ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

.Ian West
Geology of the Purbeck Fossil Forest
''Geology of the Wessex Coast of Southern England''. It lies on the

Jurassic Coast The Jurassic Coast is a World Heritage Site on the English Channel coast of southern England. It stretches from Exmouth in East Devon to Studland Bay in Dorset, a distance of about , and was inscribed on the World Heritage List in mid-Decembe ...

, on a wide ledge in the seaside cliff. The site is within the

Lulworth Ranges The Lulworth Ranges are military firing ranges located between Wareham and Lulworth in Dorset, England. They cover an area of more than , are leased in a rolling contract from the Weld Estate by the Ministry of Defence and are part of the Armoure ...

and thus has restricted access. Parts of forest can also be seen on the

Isle of Portland An isle is an island, land surrounded by water. The term is very common in British English British English (BrE, en-GB, or BE) is, according to Lexico, Oxford Dictionaries, "English language, English as used in Great Britain, as distinct fr ...

and in quarries near the town of Weymouth to the west.The Fossil Forest: Range WalksJurassic Coast
.

History

Near the end of the

Jurassic period The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...

(c.144 million years ago) the sea levels dropped and a number of islands emerged in the Purbeck area, surrounded by saline lagoons and channels. For a short period, soil formed and a tropical forest grew up. It then flooded under a shallow saline

lagoon A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') ...

. The remains are now preserved as the Fossil Forest. This provides the most complete fossilised record of a Jurassic forest in the world. The ''c''. 140-million-year-old

Gymnosperm The gymnosperms ( lit. revealed seeds) are a group of seed-producing plants that includes conifers, cycads, '' Ginkgo'', and gnetophytes, forming the clade Gymnospermae. The term ''gymnosperm'' comes from the composite word in el, γυμν ...

trees bear similarities with modern-day Cypress ('' Cupressus''), with foliage having the characteristics of a 'Monkey Puzzle' (''

Araucaria araucana ''Araucaria araucana'' (commonly called the monkey puzzle tree, monkey tail tree, piñonero, pewen or Chilean pine) is an evergreen tree growing to a trunk diameter of 1–1.5 m (3–5 ft) and a height of 30–40 m (100–130 ft). ...

''). Because of its closeness to ''Cupressus'', the species found here at the fossilized forest has been named ''Protocupressinoxylon purbeckensis'' (i.e. 'Early cypress-wood from the Purbecks'). Dendrochronology indicates that they grew in a

Mediterranean climate A Mediterranean climate (also called a dry summer temperate climate ''Cs'') is a temperate climate sub-type, generally characterized by warm, dry summers and mild, fairly wet winters; these weather conditions are typically experienced in the ...

. Some of tree stumps show the remains of

thrombolite Thrombolites (from Ancient Greek θρόμβος ''thrómbos'' meaning " clot" and λῐ́θος ''líthos'' meaning "stone") are clotted accretionary structures formed in shallow water by the trapping, binding, and cementation of sedimentary g ...

s. ''Purbeckensis'' is fairly easily distinguished from other species of prehistoric tree, due to the timbers' characteristic "cross-field pitting". Algal

stromatolites Stromatolites () or stromatoliths () are layered sedimentary formations (microbialite) that are created mainly by photosynthetic microorganisms such as cyanobacteria, sulfate-reducing bacteria, and Pseudomonadota (formerly proteobacteria). Th ...

can be observed upon some of the stumps. The Fossil Forest at Dorset has been described as "one of the most complete fossilized forest of any age".

References

Bibliography

* {{coord, 50.6163, -2.2408, type:landmark_region:GB, display=title Mesozoic paleontological sites of Europe Geology of Dorset Forests and woodlands of Dorset Jurassic Coast Isle of Portland Petrified forests Jurassic paleontological sites

History

See also

References

Bibliography