Vale of Glamorgan
The Vale of Glamorgan referred to as The Vale, is a county borough in Wales, bordering Bridgend and Rhondda Cynon Taf. With an economy based on agriculture and chemicals, it is the southernmost unitary authority in Wales. Attractions include Barry Island Pleasure Park, the Barry Tourist Railway, Porthkerry Park, St Donat's Castle, Cosmeston Lakes Country Park and Cosmeston Medieval Village, it is the location of Atlantic College, one of the United World Colleges. The largest town is Barry. Other towns include Llantwit Major and Cowbridge. There are many villages in the county borough. In medieval times, the village of Cosmeston, near what is today Penarth in the south east of the county, grew up around a fortified manor house constructed sometime around the 12th century by the De Costentin family; the De Costentins, who originated on the Cotentin peninsula in northern France, were among the first Norman invaders of Wales in the early 12th century following William the Conqueror's invasion of neighbouring England in 1066.
The village would have consisted of a number of small stone round houses, or crofts, with thatched roofs. Clemenstone, to the west, was the seat of several high sheriffs of Glamorganshire, including John Curre, known have occupied the estate in 1712. William Curre, known to have lived in Clemenstone in 1766, was an occupant of Itton Court in Monmouthshire. In the early 19th century, Lady Sale née Wynch, wife of Sir Robert Sale, spent much of her early life on the Clemenstone Estate. In 1974, the area became part of South Glamorgan, under the Local Government Act 1972, it created several problems in local governance, between the South Glamorgan County Council, Cardiff City Council and the Vale of Glamorgan Borough Council owing to their conflicting interests. It was a turbulent time for governance in the city of Cardiff, as for the first time in its history it had to share authority with the county council, larger and better resourced. In April 1996, the Vale of Glamorgan became a county borough of Wales, after forming part of South Glamorgan county.
Located to the west of Cardiff between the M4 motorway and the Severn Estuary, the Vale of Glamorgan covers 33,097 hectares and has 53 km of coastline. The largest centre of population is Barry. Other towns include Dinas Powys, Llantwit Major and Penarth. Much of the population inhabits villages and individual farms; the area is low-lying, with a maximum height of 137.3 metres above sea level at Tair Onen to the east of Cowbridge. The borough borders Cardiff to the north east, Rhondda Cynon Taf to the north, Bridgend to the north west and the Bristol Channel to the south; the yellow-grey cliffs on the Glamorgan Heritage Coast are unique on the Celtic Sea coastline as they are formed of a combination of liassic limestone and carboniferous sandstone/limestone. They were formed 200 million years ago when the whole area lay underneath a warm, equatorial sea at the start of the Jurassic Era, thus today the cliffs contain traces such as ammonites. The stratification of overlapping shale and limestone was caused by a geological upheaval known as the Variscan orogeny, which pushed the cliffs out of the sea, contorting them as they did so.
This stratification can be found on other parts of the Celtic seaboard, such as Bude in Cornwall, across the Bristol Channel. The calcium carbonate in the soil allows crops to be grown which would be difficult elsewhere in Wales or the West Country: most of the West Country has poor quality and acidic Devonian soils); the liassic limestone and carboniferous sandstone are used in the Vale as building materials. As the Glamorgan Heritage Coast faces westwards out to the Atlantic, it bears the brunt of onshore winds: ideal for surfing, but a nuisance for ships sailing up the Bristol Channel to Cardiff; as in North Cornwall and South-West Ireland, the fierce Atlantic gales created ideal conditions for deliberate shipwrecking, which until 100 years ago was common along the coast. Nash Point and Ogmore-by-Sea have some of the highest shipwreck victims on the coast of Wales; the Vale of Glamorgan was determined to be the wealthiest area in Wales in a 2003 survey conducted by Barclays Bank that measured disposable income.
Chemical industries are located to the east of the port of Barry while further inland the main activity is agriculture beef and dairy cattle, with marketing facilities at Cowbridge. The Vale of Glamorgan parliamentary and assembly constituencies sway between Labour control and Conservative Party control in both the National Assembly for Wales and Westminster. There is substantial Labour support in the east of the constituency and in the town of Barry, substantial Conservative support in the agricultural area in the west. Since 2017, there has
In the geological timescale, the Tithonian is the latest age of the Late Jurassic epoch or the uppermost stage of the Upper Jurassic series. It spans the time between 152.1 ± 4 145.0 ± 4 Ma. It is followed by the Berriasian stage; the Tithonian was introduced in scientific literature by German stratigrapher Albert Oppel in 1865. The name Tithonian is unusual in geological stage names. Tithonus was the son of Laomedon of Troy, he fell in love with Eos, the Greek goddess of dawn and finds his place in the stratigraphy because this stage, the Tithonian, finds itself hand in hand with the dawn of the Cretaceous. The base of the Tithonian stage is at the base of the ammonite biozone of Hybonoticeras hybonotum. A global reference profile for the base of the Tithonian had in 2009 not yet been established; the top of the Tithonian stage is marked by the first appearance of small globular calpionellids of the species Calpionella alpina, at the base of the Alpina Subzone. The Tithonian is subdivided into Lower/Early and Upper/Late substages or subages.
The Late Tithonian is coeval with the Portlandian stage of British stratigraphy. The Tithonian stage contains seven ammonite biozones in the Tethys domain, from top to base: zone of Durangites zone of Micracanthoceras micranthum zone of Micracanthoceras ponti or Burckardticeras peroni zone of Semiformiceras fallauxi zone of Semiformiceras semiforme zone of Semiformiceras darwini zone of Hybonoticeras hybonotum In the ocean of Tethys, the Tithonian has a calcareous facies with a typical cephalopod fauna; the Solnhofen limestone of southern Germany, known for its fossils, is of Tithonian age. Gradstein, F. M.. G. & Smith, A. G.. Oppel, C. A.. GeoWhen Database - Tithonian Jurassic-Cretaceous timescale, at the website of the subcommission for stratigraphic information of the ICS Stratigraphic chart of the Upper Jurassic, at the website of Norges Network of offshore records of geology and stratigraphy
Navajo Sandstone is a geological formation in the Glen Canyon Group, spread across the U. S. states of southern Nevada, northern Arizona, northwest Colorado, Utah as part of the Colorado Plateau province of the United States. The Navajo Sandstone is prominent in southern Utah, where it forms the main attractions of a number of national parks and monuments including Red Rock Canyon National Conservation Area, Zion National Park, Capitol Reef National Park, Glen Canyon National Recreation Area, Grand Staircase-Escalante National Monument, Canyonlands National Park. Navajo Sandstone overlies and interfingers with the Kayenta Formation of the Glen Canyon Group. Together, these formations can result in immense vertical cliffs of up to 2,200 feet. Atop the cliffs, Navajo Sandstone appears as massive rounded domes and bluffs that are white in color. Navajo Sandstone occurs as spectacular cliffs, cuestas and bluffs rising from the desert floor, it can be distinguished from adjacent Jurassic sandstones by its white to light pink color, meter-scale cross-bedding, distinctive rounded weathering.
The wide range of colors exhibited by the Navajo Sandstone reflect a long history of alteration by groundwater and other subsurface fluids over the last 190 million years. The different colors, except for white, are caused by the presence of varying mixtures and amounts of hematite and limonite filling the pore space within the quartz sand comprising the Navajo Sandstone; the iron in these strata arrived via the erosion of iron-bearing silicate minerals. This iron accumulated as iron-oxide coatings, which formed after the sand had been deposited. After having been buried, reducing fluids composed of water and hydrocarbons flowed through the thick red sand which once comprised the Navajo Sandstone; the dissolution of the iron coatings by the reducing fluids bleached large volumes of the Navajo Sandstone a brilliant white. Reducing fluids transported the iron in solution. Where the oxidizing and reducing fluids mixed, the iron precipitated within the Navajo Sandstone. Depending on local variations within the permeability, porosity and other inherent rock properties of the sandstone, varying mixtures of hematite and limonite precipitated within spaces between quartz grains.
Variations in the type and proportions of precipitated iron oxides resulted in the different black, crimson, orange, peach, pink and yellow colors of the Navajo Sandstone. The precipitation of iron oxides formed laminea, corrugated layers and pipes of ironstone within the Navajo Sandstone. Being harder and more resistant to erosion than the surrounding sandstone, the ironstone weathered out as ledges, fins, "flags", other minor features, which stick out and above the local landscape in unusual shapes; the age of the Navajo Sandstone is somewhat controversial. It may originate from the Late Triassic but is at least as young as the Early Jurassic stages Pliensbachian and Toarcian. There is no type locality of the name, it was named for the'Navajo Country' of the southwestern United States. The two major subunits of the Navajo are the Shurtz Sandstone Tongue; the Navajo Sandstone was named as the uppermost formation of the La Plata Group by Gregory and Stone in 1917. Baker reassigned it as the upper formation of Glen Canyon Group in 1936.
Its age was modified by Lewis and others in 1961. The name was not used in northwest Colorado and northeast Utah, where the name'Glen Canyon Sandstone' was preferred, its age was modified again by Padian in 1989. The sandstone was deposited in an arid erg on the Western portion of the Supercontinent Pangaea; this region was affected by annual monsoons that came about each winter when cooler winds and wind reversal occurred. Navajo Sandstone outcrops are found in these geologic locations: Colorado Plateau Black Mesa Basin Great Basin province Paradox Basin Piceance Basin Plateau sedimentary province San Juan Basin Uinta Basin Uinta Uplift Uncompaghre UpliftThe formation is found in these parklands: Glen Canyon National Recreation Area Grand Staircase-Escalante National Monument Zion National Park Canyonlands National Park Capitol Reef National Park Arches National Park Dinosaur National Monument Navajo National Monument Colorado National Monument Pink coral sand dunes, Utah Indeterminate theropod remains geographically located in Arizona, USA.
Theropod tracks are geographically located in Arizona and Utah, USA. Ornithischian tracks located in Arizona, USA; the Navajo Sandstone is well known among rockhounds for its hundreds of thousands of iron oxide concretions. Informally, they are called "Moqui marbles" and are believed to represent an extension of Hopi Native American traditions regarding ancestor worship. Thousands of these concretions weather out of outcrops of the Navajo Sandstone within south-central and southeastern Utah within an area extending from Zion National Park eastward to Arches and Canyonland national parks, they are quite abundant within Grand Staircase-Escalante National Monument. The iron oxide concretions shapes, their shape ranges from spheres to discs. Although many of these concretions are fused together like soap bubbles, many more occur as isolated concretions, which range in diameter from the size of peas to baseballs; the surface of these spherical concretions can range fr
The Blue Lias is a geologic formation in southern and western England and parts of South Wales, part of the Lias Group. The Blue Lias consists of a sequence of limestone and shale layers, laid down in latest Triassic and early Jurassic times, between 195 and 200 million years ago; the Blue Lias is famous for its fossils ammonites. Its age corresponds to the Rhaetian to lower Sinemurian stages of the geologic timescale, thus including the Hettangian stage, it is the lowest of the three divisions of the Lower Jurassic period and, as such, is given the name Lower Lias. Stratigraphically it can be subdivided into three members: the Wilmcote Limestone, Saltford Shale and Rugby Limestone; the Blue Lias comprises decimetre scale alternations of argillaceous mudstone. These alternations are caused by short-term climatic variations during the Early Jurassic attributed to orbital forcing; these limestone-mudstone alternations pass up into a clay member known as the Lower Lias Clay now the Charmouth Mudstone.
This lithology consists of monotonous mudstones weathering to clay at the surface. Sparse thin limestone and nodule bands are seen; the deposition of a clay-rich mudstone member indicates deposition in a deeper marine environment. In certain restricted parts of Britain, the lowermost member of the Blue Lias is the Wilmcote Limestone, it lies beneath the Saltford Shale Member. The Wilmcote Limestone of central England was quarried close to Stratford-upon-Avon, for example at Wilmcote, Temple Grafton and Binton, it is 200 million years old, dating back to the dawn of the Jurassic Period. Much of the Wilmcote Limestone is fine-grained, blue-grey when fresh, finely layered. Fossils are quite rare, except in the lowest beds, it was used for a variety of purposes, including walling, paving, cement-making and as a source of agricultural lime. It is no longer quarried, most of the old quarries are either infilled or overgrown. Geologists think that the Wilmcote Limestone originated as layers of fine-grained mud on the floor of a sheltered, shallow muddy sea or lagoon that covered parts of central England at the dawn of the Jurassic Period.
Little life could tolerate the stagnant conditions on the seabed. As a consequence the mud was disturbed, why the fine, paper-like layering is preserved. Above the sea bed, the shallower waters supported ammonites and marine reptiles, their remains were discovered in the Wilmcote Limestone quarries during the nineteenth century. The Warwickshire Museum houses a collection of these fossils and some are on display at the Market Hall Museum in Warwick; the Blue Lias is a prevalent feature of the cliffs around Lyme Regis and Charmouth, on the Jurassic Coast in Dorset, where it exists in layers of limestone interspersed with softer clay. It is notable for its presence in Somerset around the Polden Hills, Keinton Mandeville and Glastonbury area, it forms a broad plain across the East Midlands, it appears near Whitby in Yorkshire and Southam in Warwickshire where a pub is named after it. There are outcrops along the coast of South Wales, notably that of the Vale of Glamorgan; the type section of the Blue Lias is at Saltford near Bath.
Blue Lias is useful as a building stone, as a source of lime for making lime mortar. Because it is argillaceous, the lime is hydraulic. Since the mid-nineteenth century, it has been used as a raw material for cement, in South Wales, Somerset and Leicestershire; the cement plant quarry at Rugby, Warwickshire is the best exposure of the formation: more than 100 layers can be seen. In areas where Blue Lias is quarried it has been used in buildings and churches as well as tombstones in cemeteries. An example of a Blue Lias town is Street, near Glastonbury. Other examples of Blue Lias buildings can be found in the nearby towns of Ilchester, it remains popular in more modern-day surroundings where it is used in the construction of new housing developments and extensions for existing buildings in conservation areas. Blue Lias is used in flooring and paving slabs – both coursed and layered, it is used in the making of flagstones and cobbles. There are only four quarries in Somerset quarrying Blue Lias at present.
AR Purnell at Ashen Cross Quarry in Somerton have been mining blue lias stone since 1996. Hadspen Quarry Ltd. Hadspen Quarry operate one in Keinton Mandeville. Ham & Doulting Stone Co Ltd. operate one of Tout Quarry near Somerton. The rock is rich in fossil remains from the Jurassic period; the blue-grey colour is provided by its iron content, enclosed to a large extent in pyrites. White Lias List of dinosaur-bearing rock formations "Explore the Jurassic Coast" at the National Trust The Philpot Museum website Geology of Whitby Geology of Lyme Regis Area Geology of the Wessex Coast Ham & Doulting Stone Co Ltd Conservation of Blue lias article Fossils of the Blue Lias Formation -- A quick guide Hadspen Quarry Ltd AR Purnell Ltd
In geology and related fields, a stratum is a layer of sedimentary rock or soil, or igneous rock that were formed at the Earth's surface, with internally consistent characteristics that distinguish it from other layers. The "stratum" is the fundamental unit in a stratigraphic column and forms the basis of the study of stratigraphy; each layer is one of a number of parallel layers that lie one upon another, laid down by natural processes. They may extend over hundreds of thousands of square kilometers of the Earth's surface. Strata are seen as bands of different colored or differently structured material exposed in cliffs, road cuts and river banks. Individual bands may vary in thickness from a few millimeters to a kilometer or more. A band may represent a specific mode of deposition: river silt, beach sand, coal swamp, sand dune, lava bed, etc. Geologists categorize them by the material of beds; each distinct layer is assigned to the name of sheet based on a town, mountain, or region where the formation is exposed and available for study.
For example, the Burgess Shale is a thick exposure of dark fossiliferous, shale exposed high in the Canadian Rockies near Burgess Pass. Slight distinctions in material in a formation may be described as "members". Formations are collected into "groups" while groups may be collected into "supergroups". Archaeological horizon Geologic formation Geologic map Geologic unit Law of superposition Bed GeoWhen Database
The Jurassic period was a geologic period and system that spanned 56 million years from the end of the Triassic Period 201.3 million years ago to the beginning of the Cretaceous Period 145 Mya. The Jurassic constitutes the middle period of the Mesozoic Era known as the Age of Reptiles; the start of the period was marked by the major Triassic–Jurassic extinction event. Two other extinction events occurred during the period: the Pliensbachian-Toarcian extinction in the Early Jurassic, the Tithonian event at the end; the Jurassic period is divided into three epochs: Early and Late. In stratigraphy, the Jurassic is divided into the Lower Jurassic, Middle Jurassic, Upper Jurassic series of rock formations; the Jurassic is named after the Jura Mountains within the European Alps, where limestone strata from the period were first identified. By the beginning of the Jurassic, the supercontinent Pangaea had begun rifting into two landmasses: Laurasia to the north, Gondwana to the south; this created more coastlines and shifted the continental climate from dry to humid, many of the arid deserts of the Triassic were replaced by lush rainforests.
On land, the fauna transitioned from the Triassic fauna, dominated by both dinosauromorph and crocodylomorph archosaurs, to one dominated by dinosaurs alone. The first birds appeared during the Jurassic, having evolved from a branch of theropod dinosaurs. Other major events include the appearance of the earliest lizards, the evolution of therian mammals, including primitive placentals. Crocodilians made the transition from a terrestrial to an aquatic mode of life; the oceans were inhabited by marine reptiles such as ichthyosaurs and plesiosaurs, while pterosaurs were the dominant flying vertebrates. The chronostratigraphic term "Jurassic" is directly linked to the Jura Mountains, a mountain range following the course of the France–Switzerland border. During a tour of the region in 1795, Alexander von Humboldt recognized the limestone dominated mountain range of the Jura Mountains as a separate formation that had not been included in the established stratigraphic system defined by Abraham Gottlob Werner, he named it "Jura-Kalkstein" in 1799.
The name "Jura" is derived from the Celtic root *jor via Gaulish *iuris "wooded mountain", borrowed into Latin as a place name, evolved into Juria and Jura. The Jurassic period is divided into three epochs: Early and Late. In stratigraphy, the Jurassic is divided into the Lower Jurassic, Middle Jurassic, Upper Jurassic series of rock formations known as Lias and Malm in Europe; the separation of the term Jurassic into three sections originated with Leopold von Buch. The faunal stages from youngest to oldest are: During the early Jurassic period, the supercontinent Pangaea broke up into the northern supercontinent Laurasia and the southern supercontinent Gondwana; the Jurassic North Atlantic Ocean was narrow, while the South Atlantic did not open until the following Cretaceous period, when Gondwana itself rifted apart. The Tethys Sea closed, the Neotethys basin appeared. Climates were warm, with no evidence of a glacier having appeared; as in the Triassic, there was no land over either pole, no extensive ice caps existed.
The Jurassic geological record is good in western Europe, where extensive marine sequences indicate a time when much of that future landmass was submerged under shallow tropical seas. In contrast, the North American Jurassic record is the poorest of the Mesozoic, with few outcrops at the surface. Though the epicontinental Sundance Sea left marine deposits in parts of the northern plains of the United States and Canada during the late Jurassic, most exposed sediments from this period are continental, such as the alluvial deposits of the Morrison Formation; the Jurassic was a time of calcite sea geochemistry in which low-magnesium calcite was the primary inorganic marine precipitate of calcium carbonate. Carbonate hardgrounds were thus common, along with calcitic ooids, calcitic cements, invertebrate faunas with dominantly calcitic skeletons; the first of several massive batholiths were emplaced in the northern American cordillera beginning in the mid-Jurassic, marking the Nevadan orogeny. Important Jurassic exposures are found in Russia, South America, Japan and the United Kingdom.
In Africa, Early Jurassic strata are distributed in a similar fashion to Late Triassic beds, with more common outcrops in the south and less common fossil beds which are predominated by tracks to the north. As the Jurassic proceeded and more iconic groups of dinosaurs like sauropods and ornithopods proliferated in Africa. Middle Jurassic strata are neither well studied in Africa. Late Jurassic strata are poorly represented apart from the spectacular Tendaguru fauna in Tanzania; the Late Jurassic life of Tendaguru is similar to that found in western North America's Morrison Formation. During the Jurassic period, the primary vertebrates living in the sea were marine reptiles; the latter include ichthyosaurs, which were at the peak of their diversity, plesiosaurs and marine crocodiles of the families Teleosauridae and Metriorhynchidae. Numerous turtles could be found in rivers. In the invertebrate world, several new groups appeared, including rudists (a reef-formi
In the geologic timescale, the Sinemurian is an age and stage in the Early or Lower Jurassic epoch or series. It spans the time between 199.3 ± 2 Ma and 190.8 ± 1.5 Ma. The Sinemurian is followed by the Pliensbachian. In Europe the Sinemurian age, together with the Hettangian age, saw the deposition of the lower Lias, in Great Britain known as the Blue Lias; the Sinemurian stage was defined and introduced into scientific literature by French palaeontologist Alcide d'Orbigny in 1842. It takes its name from the French town near Dijon; the calcareous soil formed from the Jurassic limestone of the region is in part responsible for the character of the classic Sancerre wines. The base of the Sinemurian stage is at the first appearance of the ammonite genera Vermiceras and Metophioceras in the stratigraphic record. A global reference profile for the Sinemurian stage is located in a cliff north of the hamlet of East Quantoxhead, 6 kilometres east of Watchet, England; the top of the Sinemurian is at the first appearances of the ammonite species Bifericeras donovani and ammonite genus Apoderoceras.
The Sinemurian contains six ammonite biozones in the Tethys domain: zone of Echioceras raricostatum zone of Oxynotoceras oxynotum zone of Asteroceras obtusum zone of Caenisites turneri zone of Arnioceras semicostatum zone of Arietites bucklandi Bloos, G. & Page, K. N.. M.. G. & Smith, A. G.. D´Orbigny, A. C. V. M. D.. 1. Terrains oolitiques ou jurassiques, Paris. Komlosaurus carbonis GeoWhen Database - Sinemurian Lower Jurassic timescale, at the website of the subcommission for stratigraphic information of the ICS Stratigraphic chart of the Lower Jurassic, at the website of Norges Network of offshore records of geology and stratigraphy