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Fan Frynych
Fan Frynych is the northernmost peak of the Fforest Fawr massif in the Brecon Beacons National Park, South Wales. It is classed as a subsidiary summit of Fan Fawr and makes up half of the Craig Cerrig-gleisiad and Fan Frynych National Nature Reserve with its sister peak Craig Cerrig-gleisiad. The summit is marked by a trig point, where the northern face of Craig Cerrig-gleisiad can be viewed. Geology The upper parts of the mountain are formed from brown-coloured sandstones of the Senni Formation. At lower level and hence older, and forming the lower northern slopes, though largely unseen, are the mudstones of the St Maughans Formation. Both are units of the Lower Old Red Sandstone of early Devonian age. Though locally variable, the rock strata dip generally towards the southeast. The northeastern flank of the mountain is defined by a NE-SW aligned geological fault, the Cribarth Fault downthrowing to the southeast, which forms a part of the Swansea Valley Disturbance. Large pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Craig Cerrig-gleisiad
Craig Cerrig-gleisiad is a subsidiary summit of Fan Fawr in the Fforest Fawr section of the Brecon Beacons National Park, South Wales. It makes up half of the Craig Cerrig-gleisiad and Fan Frynych National Nature Reserve with its sister peak Fan Frynych. The summit is marked by a pile of stones, and sits on the edge of steep north facing cliffs which provide one of the few habitats for Arctic–alpine plants this far south in the British Isles. To the south-west is Fan Llia. Geology The outstanding feature of the mountain is the L-shaped glacial cwm which faces to the northeast. Its modern form is considered to be the result of a complex history of both glacial action and rock-slope failure, a portion of the west wall having collapsed after the main part of the last ice age. Some of the debris was re-worked during the Loch Lomond Stadial and parts stretch as far as the A470 road.Richard Shakesby, Classic Landforms of the Brecon Beacons, 2002, Geological Association Landform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trig Point
A triangulation station, also known as a trigonometrical point, and sometimes informally as a trig, is a fixed surveying station, used in geodetic surveying and other surveying projects in its vicinity. The station is usually set up by a mapping organisation with known coordinates and elevation published. Numerous stations are installed on summits for purposes of visibility and prominence. A graven metal plate on the top of a pillar may provide a mounting point for a theodolite or reflector, often using some form of kinematic coupling to ensure reproducible positioning. Use Trigonometrical stations form networks of triangulation. Positions of land boundaries, roads, railways, bridges and other infrastructure can be accurately located by the network, a task essential to the construction of modern infrastructure. Apart from the known stations set up by government, some temporary trigonometrical stations are set up near construction sites for monitoring the precision and progr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beacons Way
The Beacons Way (Welsh: Ffordd y Bannau) is a waymarked long distance footpath in the Brecon Beacons National Park, Wales. It is a linear route which runs for east to west through the National Park, and passes many of the most important landmarks and mountain peaks in the mountain range. It also includes a few of the towns in the park as well as popular attractions such as Carreg Cennen Castle near Llandeilo at the western end of the path. The route Black Mountains The Beacons Way as originally conceived started in Abergavenny, Monmouthshire, at the eastern end of the National Park and headed northeast to Ysgyryd Fawr. It was later changed so that it started on the B4521 road immediately south of the hill at coordinates though the connection with Abergavenny has since been reinstated, albeit on a slightly different route: it now starts at Abergavenny railway station. Beyond Ysgyryd Fawr the route drops down to Llanfihangel Crucorney, passing The Skirrid Mountain Inn befo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rights Of Way In England And Wales
In England and Wales, excluding the 12 Inner London London boroughs, boroughs and the City of London, the Right-of-way (property access), right of way is a legally protected right of the public to pass and re-pass on specific paths. Private rights of way or easements also exist. The law in England and Wales differs from Scots law in that rights of way exist only where they are so designated (or are able to be designated if not already), whereas in Scotland any route that meets certain conditions is rights of way in Scotland, defined as a right of way, and in addition, there is a general presumption of access to the countryside (the "right to roam"). Definitive maps Definitive maps of public rights of way have been compiled for all of England and Wales, as a result of the National Parks and Access to the Countryside Act 1949, except the 12 Inner London boroughs, which, along with the City of London, were not covered by the Act. Definitive maps exist for the Outer London borough ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Countryside And Rights Of Way Act 2000
The Countryside and Rights of Way Act 2000 (c. 37), also known as the CRoW Act and "Right to Roam" Act, is a United Kingdom Act of Parliament affecting England and Wales which came into force on 30 November 2000. Right to roam The Act implements the so-called "right to roam" (also known as ''jus spatiandi'') long sought by the Ramblers' Association and its predecessors, on certain upland and uncultivated areas of England and Wales. This element of the act was implemented in stages as conclusive maps of different regions were produced. The act refers to areas of 'mountain, moor, heath and down' in addition to registered common land; not all uncultivated land is covered. Rights of way A staged review of public rights of way, including limited rights to create new public footpaths where needed, is being conducted under the Act. Again, this is being conducted in a staged manner, which can produce anomalies – of the two administrative areas of the County of Gloucestershire, ... [...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] |
Strata
In geology and related fields, a stratum (: strata) is a layer of Rock (geology), rock or sediment characterized by certain Lithology, lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as either ''Bed (geology), bedding surfaces'' or ''bedding planes''.Salvador, A. ed., 1994. ''International stratigraphic guide: a guide to stratigraphic classification, terminology, and procedure. 2nd ed.'' Boulder, Colorado, The Geological Society of America, Inc., 215 pp. . Prior to the publication of the International Stratigraphic Guide, older publications have defined a stratum as being either equivalent to a single Bed (geology), bed or composed of a number of beds; as a layer greater than 1 cm in thickness and constituting a part of a bed; or a general term that includes both ''bed'' and ''Lamination (geology), lamina''.Neuendorf, K.K.E., Mehl, Jr., J.P., and Jackson, J.A. , eds., 2005. ''Glossary of Geolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian
The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian period at million years ago (Megaannum, Ma), to the beginning of the succeeding Carboniferous period at Ma. It is the fourth period of both the Paleozoic and the Phanerozoic. It is named after Devon, South West England, where rocks from this period were first studied. The first significant evolutionary radiation of history of life#Colonization of land, life on land occurred during the Devonian, as free-spore, sporing land plants (pteridophytes) began to spread across dry land, forming extensive coal forests which covered the continents. By the middle of the Devonian, several groups of vascular plants had evolved leaf, leaves and true roots, and by the end of the period the first seed-bearing plants (Pteridospermatophyta, pteridospermatophyt ... [...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] |
Mudstone
Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from ''shale'' by its lack of fissility.Blatt, H., and R.J. Tracy, 1996, ''Petrology.'' New York, New York, W. H. Freeman, 2nd ed, 529 pp. The term ''mudstone'' is also used to describe carbonate rocks (limestone or dolomite) that are composed predominantly of carbonate mud. However, in most contexts, the term refers to siliciclastic mudstone, composed mostly of silicate minerals. The NASA Curiosity rover has found deposits of mudstone on Mars that contain organic substances such as propane, benzene and toluene. Definition There is not a single definition of mudstone that has gained general acceptance,Boggs 2006, p.143 though there is wide agreement that mudstones are fine-grained sedimentary rocks, composed mostly of silicate grains with a grain size less than . Individual grains this size are too small to be distinguished without a micros ... [...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] |
