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The Begwns
The Begwns, or sometimes The Begwyns, form a small upland area in eastern Powys, Wales. They sit within the community (Wales), communities of Painscastle, Glasbury and Clyro, to the north of a great bend in the course of the River Wye, Wye valley, west of Hay-on-Wye. ‘Begwns' is a cymricisation of the English ‘beacons’. The Begwns are 1293 acres of common land which was given to the National Trust by the Maesllwch Estate in 1992 and managed for grazing and quiet recreation. The common ranges in elevation from 250m at its lowest to 415m at ‘The Roundabout’, a hilltop wooded feature at the heart of the area. A trig point immediately outside of this enclosure is 1m lower. The trees were planted here to commemorate Queen_Victoria#Diamond_Jubilee, Queen Victoria’s Diamond Jubilee with a wall constructed around them in 1887 for protection. There are a handful of small pools on the common, of which the largest is Monks Pond. These ponds contain the increasingly uncommon aq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Powys
Powys ( , ) is a Principal areas of Wales, county and Preserved counties of Wales, preserved county in Wales. It borders Gwynedd, Denbighshire, and Wrexham County Borough, Wrexham to the north; the English Ceremonial counties of England, ceremonial counties of Shropshire and Herefordshire to the east; Monmouthshire, Blaenau Gwent, Merthyr Tydfil County Borough, Merthyr Tydfil, Caerphilly County Borough, Caerphilly, Rhondda Cynon Taf, and Neath Port Talbot to the south; and Carmarthenshire and Ceredigion to the west. The largest settlement is Newtown, Powys, Newtown, and the administrative centre is Llandrindod Wells. Powys is the largest and most sparsely populated county in Wales, having an area of and a population of in . While largely rural, its towns include Welshpool in the north-east, Newtown in the north-centre, Llandrindod Wells in the south-centre, Brecon in the south, Ystradgynlais in the far south-west, and Machynlleth in the far west. The Welsh language can be spok ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordnance Survey
The Ordnance Survey (OS) is the national mapping agency for Great Britain. The agency's name indicates its original military purpose (see Artillery, ordnance and surveying), which was to map Scotland in the wake of the Jacobite rising of 1745. There was also a more general and nationwide need in light of the potential threat of invasion during the Napoleonic Wars. Since 1 April 2015, the Ordnance Survey has operated as Ordnance Survey Ltd, a state-owned enterprise, government-owned company, 100% in public ownership. The Ordnance Survey Board remains accountable to the Secretary of State for Science, Innovation and Technology. It was also a member of the Public Data Group. Paper maps represent only 5% of the company's annual revenue. It produces digital map data, online route planning and sharing services and mobile apps, plus many other location-based products for business, government and consumers. Ordnance Survey mapping is usually classified as either "Scale (map), lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Head (geology)
Head describes deposits consisting of fragmented material which, following weathering, have moved downslope through a process of solifluction. The term has been used by British geologists since the middle of the 19th century to describe such material in a range of different settings from flat hilltops to the bottoms of valleys. Areas identified as head include deposits of aeolian origin such as blown sand and loess, slope deposits such as gelifluctates and solifluctates, and recently eroded soil material, called colluvium. With geologists becoming more interested in studying the near-surface environment and its related processes, the term head is becoming obsolete. A related term is 'combe (or coombe) rock', descriptive of a body of chalk and flint Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peat
Peat is an accumulation of partially Decomposition, decayed vegetation or organic matter. It is unique to natural areas called peatlands, bogs, mires, Moorland, moors, or muskegs. ''Sphagnum'' moss, also called peat moss, is one of the most common components in peat, although many other plants can contribute. The biological features of sphagnum mosses act to create a habitat aiding peat formation, a phenomenon termed 'habitat manipulation'. Soils consisting primarily of peat are known as histosols. Peat forms in wetland conditions, where flooding or stagnant water obstructs the flow of oxygen from the atmosphere, slowing the rate of decomposition. Peat properties such as organic matter content and saturated hydraulic conductivity can exhibit high spatial heterogeneity. Peatlands, particularly bogs, are the primary source of peat; although less common, other wetlands, including fens, pocosins and peat swamp forests, also deposit peat. Landscapes covered in peat are home to sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swansea Valley Disturbance
The Cribarth Disturbance is a geological structure forming a lineament which stretches across south Wales from Swansea up the Swansea Valley then northeastwards to Brecon and beyond. It consists of both a series of faults and associated folds which were active during the mountain-building period known as the Variscan orogeny. This line of weakness probably featured in the earlier Caledonian Orogeny and perhaps reflects a more ancient line of weakness in the basement rocks. It is also known (in part) as the Tawe Valley Disturbance or the Swansea Valley Disturbance. Influence on the landscape The Disturbance is responsible for a number of significant landscape features along its 50 km length. Prominent amongst these is the Swansea Valley, formed both by glacial action during the ice ages and river erosion along this line of weakness in the Earth's crust between Abercraf and Swansea. It is now occupied by the River Tawe. The geologically complex mountain of Cribarth also lies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a Fracture (geology), planar fracture or discontinuity in a volume of Rock (geology), rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust (geology), crust result from the action of Plate tectonics, plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction, subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the Plane (geometry), plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geological maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ludlovian
The Ludlow Group are geologic formations deposited during the Ludlow epoch of the Silurian period in the British Isles, in areas of England, Ireland, Scotland, and Wales. Formations This group contains the following formations in descending order: # Tilestones Formation, Downton Castle Sandstone formation (90 ft./27.7 m), # Ledbury Formation shales 270 ft./83 m), # Upper Ludlow sub-group formation (140 ft./43 m), # Aymestry Limestone Formation (up to 40 ft./12.3 m), # Lower Ludlow sub-group formation (350 to 780 ft./108 m-240 m). Geology The Ludlow group is essentially shaly in character, except towards the top, where the beds become more sandy and pass gradually into the Old Red Sandstone. The Aymestry limestone, which is irregular in thickness, is sometimes absent, and where the underlying Wenlock limestones are absent the shales of the Ludlow group graduate, downwards into the Wenlock shales. In Wales the group is typically developed between n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wenlockian
The Wenlock Epoch (sometimes referred to as the Wenlockian) is the second epoch of the Silurian. It is preceded by the Llandovery Epoch and followed by the Ludlow Epoch. Radiometric dates constrain the Wenlockian between and million years ago. Naming and history The Wenlock is named after Wenlock Edge, an outcrop of rocks near the town of Much Wenlock in Shropshire ( West Midlands, United Kingdom). The name was first used in the term "Wenlock and Dudley rocks" by Roderick Murchison in 1834 to refer to the limestones and underlying shales that underlay what he termed the "Ludlow rocks". He later modified this term to simply the "Wenlock rocks" in his book, ''The Silurian System'' in 1839. Definition and subdivision The Wenlock's beginning is defined by the lower boundary (or GSSP) of the Sheinwoodian. The end is defined as the base (or GSSP) of the Gorstian. The Wenlock is divided into the older Sheinwoodian and the younger Homerian In the geologic timescale, the Homer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar, because they are the most resistant minerals to the weathering processes at the Earth's surface. Like uncemented sand, sandstone may be imparted any color by impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Because sandstone beds can form highly visible cliffs and other topography, topographic features, certain colors of sandstone have become strongly identified with certain regions, such as the red rock deserts of Arches National Park and other areas of the Southwestern United States, American Southwest. Rock formations composed of sandstone usually allow the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brecon Beacons National Park
Brecon Beacons National Park, officially named Bannau Brycheiniog National Park (), is a National parks of the United Kingdom, national park in Wales. It is named after the Brecon Beacons (), the mountain range at its centre. The national park includes the highest mountain in South Wales, Pen y Fan, which has an elevation of . The national park has a total area of . The Brecon Beacons and Fforest Fawr uplands form the central section of the park. To the east are the Black Mountains, Wales, Black Mountains, which extend beyond the national park boundary into England, and to the west is the similarly named but distinct Black Mountain (range), Black Mountain range. These ranges share much of the same basic geology, the southerly dip of the rock strata leading to north-facing escarpments. The highest peak of the Black Mountains is Waun Fach (), and Fan Brycheiniog () is the highest of the Black Mountain. The park was founded in 1957 and is the third and most recently designated Nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Old Red Sandstone
Old Red Sandstone, abbreviated ORS, is an assemblage of rocks in the North Atlantic region largely of Devonian age. It extends in the east across Great Britain, Ireland and Norway, and in the west along the eastern seaboard of North America. It also extends northwards into Greenland and Svalbard. These areas were a part of the paleocontinent of Euramerica (Laurussia). In Britain it is a lithostratigraphic unit (a sequence of rock strata) to which stratigraphers accord supergroup status and which is of considerable importance to early paleontology. The presence of ''Old'' in the name is to distinguish the sequence from the younger New Red Sandstone which also occurs widely throughout Britain. Sedimentology The Old Red Sandstone describes a group of sedimentary rocks deposited in a variety of environments in the late Silurian, through the Devonian and into the earliest part of the Carboniferous. The body of rock, or facies, is dominated by terrigenous deposits and co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
