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53-792: The Wrekin Terrane is one of five inferred fault bounded terranes that make up the basement rocks of the southern United Kingdom. The other notable geological terranes in the region are the Charnwood Terrane , Fenland Terrane , Cymru Terrane and the Monian Composite Terrane . The Wrekin Terrane is bounded to the west by the Welsh Borderland Fault System and to the east by the Malvern Lineament . The geological terrane to

106-697: A supereon , but this is also an informal term, not defined by the ICS in its chronostratigraphic guide. Eozoic (from eo- "earliest") was a synonym for pre-Cambrian , or more specifically Archean . A specific date for the origin of life has not been determined. Carbon found in 3.8 billion-year-old rocks (Archean Eon) from islands off western Greenland may be of organic origin. Well-preserved microscopic fossils of bacteria older than 3.46 billion years have been found in Western Australia . Probable fossils 100 million years older have been found in

159-567: A fog descends and takes away my visibility..." In Edward Lear 's A Book of Nonsense , one of the limericks starts: There was an Old Man of the Wrekin Whose shoes made a horrible creaking In 2017, during an attempt by the high-street chain Poundland to challenge the trademark of Mondelēz 's Toblerone bar with their own Twin Peaks confectionery, they claimed that the latter was inspired by

212-587: A giant-sized spadeful of earth and set off towards the town. When in the vicinity of Wellington he met a cobbler returning from Shrewsbury market with a large sackful of shoes for repair. The giant asked him for directions, adding that he was going to dump his spadeful of earth in the River Severn and flood the town. "It's a very long way to Shrewsbury," replied the quick-thinking shoemaker. "Look at all these shoes I've worn out walking back from there!" The giant immediately decided to abandon his enterprise and dumped

265-660: A large group of people all held hands, surrounding the hill at the base. The Wrekin has a cheese named after it called Wrekin White, which is produced and sold in a dairy in Newport, Shropshire . In September 2010, Wiccans conducted a wicker man burning ceremony at the Wrekin to celebrate the autumnal equinox . The Wrekin is mentioned in Poem XXXI of A.E. Housman 's collection A Shropshire Lad . The first stanza runs: On Wenlock Edge

318-504: A late 11th century Worcester cartulary , spelled Wreocensetun . Its modern form is believed to have come into modern English by way of Mercian , and that is likely to have been taken from the British Celtic Wrikon- . Dinlle Wrecon meaning the fort of Wrecon appears as a place name in the early Welsh poems known as Canu Heledd . There is an Iron Age hill fort on the summit almost 8 ha (20 acres) in size, to which

371-713: A possible 2450 Ma red alga from the Kola Peninsula , 1650 Ma carbonaceous biosignatures in north China, the 1600 Ma Rafatazmia , and a possible 1047 Ma Bangiomorpha red alga from the Canadian Arctic. The earliest fossils widely accepted as complex multicellular organisms date from the Ediacaran Period. A very diverse collection of soft-bodied forms is found in a variety of locations worldwide and date to between 635 and 542 Ma. These are referred to as Ediacaran or Vendian biota . Hard-shelled creatures appeared toward

424-719: A succession of rocks of early Carboniferous age including limestone , the Little Wenlock Basalt and the Lydebrook Sandstone. Structurally, the Wrekin together with the Ercall forms part of the Church Stretton Complex where different geological terranes meet. The Cymru Terrane is to the west with the Wrekin Terrane to the east of the fault system. The fault system trends north-northeast:south-southwest and

477-456: A volcanic island arc , similar to modern Japan – are approximately 680   million years old. Dolerite dykes intruded the extrusive volcanic rocks around 563   million years ago. A variety of the intrusive igneous rock granophyre , known as Ercallite forms the northeastern shoulder of the Ercall. It was put in place around 560   million years ago and is overlain by Cambrian rocks of sedimentary origin. The southeastern side of

530-529: Is a beacon which emits a red pulse of light every few seconds at night. A beacon was originally erected on the Wrekin during the Second World War to warn aircraft, and was kept in operation until 1960. A new beacon was then installed in 2000, as part of a project to celebrate the new millennium. It is known locally as the "Wrekin Beacon", and is visible for many miles around. The trig point and toposcope at

583-527: Is a hill in east Shropshire , England. It is located some five miles (8 km) west of Telford , on the border between the unitary authorities of Shropshire and Telford and Wrekin . Rising above the Shropshire Plain to a height of 407 metres (1,335 ft) above sea level, it is a prominent and well-known landmark, signalling the entrance to Shropshire for travellers westbound on the M54 motorway . The Wrekin

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636-761: Is contained within the northern salient of the Shropshire Hills AONB . The hill is popular with walkers and tourists and offers good views of Shropshire. It can be seen well into Staffordshire and the Black Country , and even as far as the Beetham Tower in Manchester, Winter Hill in Lancashire and Cleeve Hill in Gloucestershire. The earliest mention of the Wrekin occurs in a charter of 855, as entered in

689-487: Is contrasting to that of the rest of the Wrekin Terrane being of a volcanic arc formed on oceanic or on thin, immature continental crust . The Supergroup consists of c.6000 m of sedimentary rocks with varying facies from basinal and distal turbidite to deltaic and fluviatile successions which exhibits a generally regressive sequence. The Longmyndian is separated into two main depositionally distinguishable units:

742-651: Is known to occur during the RNA replication of extant coronaviruses . Evidence of the details of plate motions and other tectonic activity in the Precambrian is difficult to interpret. It is generally believed that small proto-continents existed before 4280 Ma, and that most of the Earth's landmasses collected into a single supercontinent around 1130 Ma. The supercontinent, known as Rodinia , broke up around 750 Ma. A number of glacial periods have been identified going as far back as

795-515: Is steep in parts. The Wrekin is owned by the Raby Estate , currently headed by Henry Francis Cecil Vane . The Wrekin is the subject of a well-known legend in Shropshire folklore . One version of the story runs as follows: A giant called Gwendol Wrekin ap Shenkin ap Mynyddmawr with a grudge against the town of Shrewsbury decided to flood the town and kill all its inhabitants. So he collected

848-430: Is suggestive of a former volcanic centre being in close proximity and deposition in a subaerial environment. The Coomb Volcanic Formation occupies much of the south-west of the Wrekin Terrane and its associated inliers . The sequence is the most recent suite of Neoproterozoic rocks identified in southern Britain. The formation consists of over 1000 m of sediments deposited in a subaqueous environment (in contrast to

901-514: Is thought that the Earth coalesced from material in orbit around the Sun at roughly 4,543 Ma, and may have been struck by another planet called Theia shortly after it formed, splitting off material that formed the Moon (see Giant-impact hypothesis ). A stable crust was apparently in place by 4,433 Ma, since zircon crystals from Western Australia have been dated at 4,404 ± 8 Ma. The term "Precambrian"

954-693: Is used by geologists and paleontologists for general discussions not requiring a more specific eon name. However, both the United States Geological Survey and the International Commission on Stratigraphy regard the term as informal. Because the span of time falling under the Precambrian consists of three eons (the Hadean , the Archean , and the Proterozoic ), it is sometimes described as

1007-403: The Black Country , Birmingham to mean "the long way round", in the same way that "round the houses" is used more widely. "To all friends around the Wrekin", meanwhile, is a toast traditionally used in Shropshire, especially at Christmas and New Year. The amount of inclement weather in the area can also be said to be predicted by the visibility of the Wrekin. The saying being, "If you can see

1060-521: The Huronian epoch, roughly 2400–2100 Ma. One of the best studied is the Sturtian-Varangian glaciation, around 850–635 Ma, which may have brought glacial conditions all the way to the equator, resulting in a " Snowball Earth ". The atmosphere of the early Earth is not well understood. Most geologists believe it was composed primarily of nitrogen, carbon dioxide, and other relatively inert gases, and

1113-662: The Stretton Group and the Wentnor Group . The succession is geographically positioned between the Pontesford-Linley Fault System and the Church Stretton Fault System which has been folded, possibly during the late Neoproterozoic , and is inferred to gently plunge to the south. The succession is predominantly siliciclastic but with minor intrusions noted. A basal age (from a bentonite horizon) of

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1166-530: The Warren House Formation being in thrust contact with the Malvern Complex. The Warren House Formation is composed of pillow basalts , intermediate lavas , altered rhyolites and welded and non-welded acid tuffs with evidence to suggest that they are linked via fractional crystallisation . U-Pb zircon dating gives an age of 566 Ma+/-2 Ma. The geochemical signature from this sequence

1219-511: The geologic time scale . It spans from the formation of Earth about 4.6 billion years ago ( Ga ) to the beginning of the Cambrian Period, about 538.8 million years ago ( Ma ), when hard-shelled creatures first appeared in abundance. Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earth's history , and what is known has largely been discovered from

1272-482: The oxygen catastrophe . At first, oxygen would have quickly combined with other elements in Earth's crust, primarily iron, removing it from the atmosphere. After the supply of oxidizable surfaces ran out, oxygen would have begun to accumulate in the atmosphere, and the modern high-oxygen atmosphere would have developed. Evidence for this lies in older rocks that contain massive banded iron formations that were laid down as iron oxides. A terminology has evolved covering

1325-401: The 1960s onwards. The Precambrian fossil record is poorer than that of the succeeding Phanerozoic , and fossils from the Precambrian (e.g. stromatolites ) are of limited biostratigraphic use. This is because many Precambrian rocks have been heavily metamorphosed , obscuring their origins, while others have been destroyed by erosion, or remain deeply buried beneath Phanerozoic strata. It

1378-671: The Stretton Group is given as 555.9 Ma+/-3.5 Ma. The Wrekin Terrane contains abundant evidence of Ediacara fauna which include the body fossil taxa Beltanelliformis brunsae and B. minutae . The body fossil Arumberia is also noted to be present in the Lightspout Formation of the Stretton Group. 52°40′08″N 2°33′07″W  /  52.669°N 2.552°W  / 52.669; -2.552 The Wrekin The Wrekin ( / ˈ r iː k ɪ n / REE -kin )

1431-626: The Welsh Borderland Fault System. The Stanner-Hanter Complex outcrops in the terrane, the complex is a magmatic intrusion (non-preserved) with a four-stage cross cutting history where acidic and basic rocks have been intermingled and hybridised with an interpreted age of 702 Ma +/-8 Ma (Stanner Hill Granophyre ). On the other side of the terrane the Malvern Complex is composed of diorite and tonalite plutons that have been altered by Proterozoic metamorphism (modifying

1484-494: The Wrekin is also used to refer more generally to the part of East Shropshire around the towns of Telford and Wellington , within sight of the hill. The surrounding area is one of the birthplaces of industry: Ironbridge Gorge is just to the south of the Wrekin hill. Woodland covers much of the hill, the area around the hill and into the Ironbridge Gorge area too. The eponymous Wrekin parliamentary constituency incorporates

1537-823: The Wrekin Range where the Uriconian rhyolite is cross cut with the Neoproterozoic Ercall Granophyre. The sedimentary record in the area varies between volcaniclastic and siliciclastic deposition, the latter being present in the Longmnyd area and the former being representative of the Stanner-Hanter and Malvern Complex. Depositional facies include the Uriconian and the Longmyndian sequences. The relationship between

1590-509: The Wrekin, it's going to rain. And if you can't see the Wrekin, it's already raining." Another well known local legend has it that you cannot be a true Salopian (person born in Shropshire) unless you have passed through the Needle's Eye - a split between two large rocks close to the summit. In 1981, an event was undertaken by local school pupils and adults called "Hands around the Wrekin", whereby

1643-401: The current scheme based upon numerical ages. Such a system could rely on events in the stratigraphic record and be demarcated by GSSPs . The Precambrian could be divided into five "natural" eons, characterized as follows: The movement of Earth's plates has caused the formation and break-up of continents over time, including occasional formation of a supercontinent containing most or all of

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1696-497: The depositional environment is that of a trans-tensional arc caused by oblique subduction. The sediments of the Uriconian are indicated to have been deposited rapidly with such volcanism being dated (U-Pb Zircon) at 566+/-2 Ma (Note the Uriconian is cross-cut by the Late Precambrian Ercall Granophyre dated 560+/-1 Ma.) The sequence is dominated by pyroclastic deposits, breccias and welded tuffs which

1749-453: The early years of the Earth's existence, as radiometric dating has allowed absolute dates to be assigned to specific formations and features. The Precambrian is divided into three eons: the Hadean (4567.3–4031 Ma), Archean (4031-2500 Ma) and Proterozoic (2500-538.8 Ma). See Timetable of the Precambrian . It has been proposed that the Precambrian should be divided into eons and eras that reflect stages of planetary evolution, rather than

1802-538: The earth on the ground beside him, where it became the Wrekin. The giant also scraped the mud off his boots, which became the smaller hill Ercall Hill nearby. Ironically Shrewsbury is subjected to flooding from the River Severn on frequent occasions naturally. "All around the Wrekin", "Right 'round the Wrekin" or "Running round the Wrekin" is a phrase common in Shropshire , Worcestershire, Staffordshire , Herefordshire ,

1855-741: The end of that time span, marking the beginning of the Phanerozoic Eon. By the middle of the following Cambrian Period, a very diverse fauna is recorded in the Burgess Shale , including some which may represent stem groups of modern taxa. The increase in diversity of lifeforms during the early Cambrian is called the Cambrian explosion of life. While land seems to have been devoid of plants and animals, cyanobacteria and other microbes formed prokaryotic mats that covered terrestrial areas. Tracks from an animal with leg-like appendages have been found in what

1908-525: The height of the summit was incorporated into an artwork, The Sky Begins At My Feet , which was designed by Wellington Arts Collective and unveiled in October 2022 in honour of the Platinum Jubilee of Elizabeth II . The sculpture is in the stoneware clay tiles laid around the plinths bearing relief portraits of seven local heroes and heroines by artist Sharon Griffin, and a range of decorative tiles designed by

1961-572: The hill. The Wrekin can be accessed from the final junction on the M54 motorway (J7) before it turns into the A5 which continues to Shrewsbury . The hill is then signposted. There is a well-used footpath up the side of the hill which has an entrance at the end of the road off the M54. There is also a small car park and parking bays up the road. Between the Ercall and the Wrekin is a well positioned car park, at Forest Glen, allowing easy access to both areas. The ascent

2014-541: The landmass. The earliest known supercontinent was Vaalbara . It formed from proto-continents and was a supercontinent 3.636 billion years ago. Vaalbara broke up c. 2.845–2.803 Ga ago. The supercontinent Kenorland was formed c. 2.72 Ga ago and then broke sometime after 2.45–2.1 Ga into the proto-continent cratons called Laurentia , Baltica , Yilgarn craton and Kalahari . The supercontinent Columbia , or Nuna, formed 2.1–1.8 billion years ago and broke up about 1.3–1.2 billion years ago. The supercontinent Rodinia

2067-410: The line carries on through other geologically important exposures such as those in the area of Caer Caradoc . Contrary to a common misconception, the Wrekin has never been a volcano in its own right, but is composed mainly of volcanic rocks and is a product of volcanism. Its modern shape, which from certain viewpoints appears to resemble a volcano, has been formed by other natural processes. The name

2120-453: The name Uriconio originally referred. It is thought the fort was built by the Cornovii tribe and was once their capital. In AD   47 Roman invaders stormed the fort and set fire to it, moving the defeated tribe on to Wroxeter ( Viroconium Cornoviorum ). A more recent addition is the Wrekin transmitting station , used for broadcasting and telecommunications. At the top of the main mast

2173-417: The original igneous textures) by still exhibit calc-alkaline, magmatic arc geochemical signatures. The date of emplacement is interpreted to be 677 Ma +/- 2 Ma with upper greenschist -lower amphibolite metamorphic cooling ages of c.650 Ma although crustal recycling is inferred from the presence of inherited zircon of 1598 Ma +/- 32 Ma. The later phases of intrusion are noted within

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2226-638: The overlying sedimentary rocks that date between 570 and 560 Ma. The signatures of the rocks are interpreted as having an intra-plate geochemical signature that may be attributed to arc-rifting. The diachronous formations of the bedded Uriconian and Coomb Volcanic Formation . Metamorphic rock is thought to underlie the Wrekin Terrane and is inferred from the outcrops associated with the Malvern Hills where outcrops of metasedimentary schist and gneiss are noted at Gullet Quarry (southern Malvern Hills). There are also outcrops of gneiss at Primrose Hill on

2279-545: The phrase “It’s just a quick ride round The Wrekin” in 2019 film “Le Mans ‘66”. The most distant visible point is probably the Forest of Bowland in north-east Lancashire. Despite historical claims, including a toposcope at the summit, it is not possible to see Snowdon from the Wrekin, as the line of sight is blocked by Cadair Berwyn . Precambrian The Precambrian is an informal unit of geologic time, subdivided into three eons ( Hadean , Archean , Proterozoic ) of

2332-501: The public and various community groups and workshops. The geology of the Wrekin and its immediate area is complex, consisting of a variety of rocks of a range of ages affected by numerous faults . The crest of the Wrekin's ridge and its northwestern slopes are formed from various rocks of volcanic origin assigned to the Uriconian series, of Precambrian age. The ' Uriconian Volcanics' include rhyolites , tuffs and agglomerates . These rocks – layers of ancient lava flows laid down in

2385-458: The ridge is largely formed from sandstones and shales of Cambrian age. They include the early Cambrian Lower Comley Sandstone and Lower Comley Limestones together with the Wrekin Quartzite, outcrops of which also occur to the northwest of the ridge. The lower ground to the northwest comprises sandstones and mudstones of late Carboniferous and Permian age whilst to the southeast are

2438-526: The same area. However, there is evidence that life could have evolved over 4.280 billion years ago. There is a fairly solid record of bacterial life throughout the remainder (Proterozoic Eon) of the Precambrian. Complex multicellular organisms may have appeared as early as 2100 Ma. However, the interpretation of ancient fossils is problematic, and "... some definitions of multicellularity encompass everything from simple bacterial colonies to badgers." Other possible early complex multicellular organisms include

2491-505: The shape of the Wrekin, which is situated in the region of Poundland's head office in Willenhall . The chocolate bar was launched that year, and is said to be based on the Wrekin and Ercall hills. Poundland's founder, Steve Smith, lives near Bridgnorth in Shropshire. The Wrekin is a location in the 2020 videogame Assassin's Creed Valhalla , as "The Wroeken". Christian Bale (playing racing driver Ken Miles, from Sutton Coldfield) uses

2544-578: The subaerial Uriconian). Explosive ash-flow tuffs mark the initial phase of deposition followed by rhyolite flows and domes. Bimodal deposition followed with lavas, minor intrusions, ash-flows and volcaniclastic rocks with some ash-flows exhibiting Ediacaran body fossils. The geochemistry notes that fractional crystallisation process within the magma chamber links the lavas with the tuffs and gives intra-plate as well as subduction geochemical signatures. The Malvern Hills represent another depositional environment for late Neoproterozoic sedimentation with

2597-519: The two is complex with some suggestion that the two are coeval and faulted as well as two unconformable strata. The former (coeval but different depositional facies) is supported by U-Pb Zircon dating from the Longmyndian bentonites. However, this is not definitive. The Uriconian sedimentary geology is mainly composed of bimodal (acidic, intermediate and basic) intra-plate volcanics with only minimal influence from subduction . The interpreted overview of

2650-615: The west is the Cymru Terrane and to the east is Charnwood Terrane. The majority of rocks in the area are associated with the outcrops that are evident at the faulted boundaries. The older rocks of the terrane rest in the Precambrian with younger Cambrian rocks resting unconformably upon them. The Precambrian rocks are noted to be calc-alkaline plutonic intrusions dated to approximately 700-600 Ma (Phase 1 to Phase 2 Neoproterozoic ). These have associated (younger) volcanics that dominate

2703-498: The wood's in trouble; His forest fleece the Wrekin heaves; The gale, it plies the saplings double, And thick on Severn snow the leaves. In the 1969 novel A Pelican at Blandings , The Wrekin can be seen from P.G. Wodehouse 's Blandings Castle . The Wrekin is also mentioned in Half Man Half Biscuit 's 1987 song, " Rod Hull Is Alive, Why?", with the line: "Halfway up the Wrekin with an empty flask of tea,

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2756-482: Was lacking in free oxygen . There is, however, evidence that an oxygen-rich atmosphere existed since the early Archean. At present, it is still believed that molecular oxygen was not a significant fraction of Earth's atmosphere until after photosynthetic life forms evolved and began to produce it in large quantities as a byproduct of their metabolism . This radical shift from a chemically inert to an oxidizing atmosphere caused an ecological crisis , sometimes called

2809-846: Was mud 551 million years ago. The RNA world hypothesis asserts that RNA evolved before coded proteins and DNA genomes. During the Hadean Eon (4,567–4,031 Ma) abundant geothermal microenvironments were present that may have had the potential to support the synthesis and replication of RNA and thus possibly the evolution of a primitive life form. It was shown that porous rock systems comprising heated air-water interfaces could allow ribozyme - catalyzed RNA replication of sense and antisense strands that could be followed by strand-dissociation, thus enabling combined synthesis, release and folding of active ribozymes. This primitive RNA replicative system also may have been able to undergo template strand switching during replication ( genetic recombination ) as

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