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Moel Oernant
Moel Oernant is a high hill in the community of Trawsfynydd in the county of Gwynedd in North Wales. It has a number of western tops, the highest of which reaches a height of overlooking the waterbody known as Llyn Gelli-Gain and another at Frîdd Wen exceeds . To the south of the lake is the top of Pîg Idris which reaches 429m. The minor top of Y-Foel attains 430m to the northeast of Moel Oernant. Geology The hill is formed largely from the mudstones, siltstone and sandstones of the Maentwrog Formation and the siltstones of the underlying Clogau Formation, component units of the Mawddach Group of Cambrian age sedimentary rocks. Sandstones and siltstones of the Gamlan Formation of the Harlech Group are also present. An igneous intrusion of microtonalite lies to the west of the summit and the whole hill is cross-cut by dykes of similar material and later dolerite. Some quartz vein mineralization is recorded within the microtonalite outcrop. A number of faults criss-cross t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Welsh Language
Welsh ( or ) is a Celtic language family, Celtic language of the Brittonic languages, Brittonic subgroup that is native to the Welsh people. Welsh is spoken natively in Wales, by some in England, and in Y Wladfa (the Welsh colony in Chubut Province, Argentina). Historically, it has also been known in English as "British", "Cambrian", "Cambric" and "Cymric". The Welsh Language (Wales) Measure 2011 gave the Welsh language official status in Wales. Both the Welsh and English languages are ''de jure'' official languages of the Welsh Parliament, the Senedd. According to the 2021 United Kingdom census, 2021 census, the Welsh-speaking population of Wales aged three or older was 17.8% (538,300 people) and nearly three quarters of the population in Wales said they had no Welsh language skills. Other estimates suggest that 29.7% (899,500) of people aged three or older in Wales could speak Welsh in June 2022. Almost half of all Welsh speakers consider themselves fluent Welsh speakers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intrusion
In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and compositions, illustrated by examples like the Palisades Sill of New York and New Jersey; the Henry Mountains of Utah; the Bushveld Igneous Complex of South Africa; Shiprock in New Mexico; the Ardnamurchan intrusion in Scotland; and the Sierra Nevada Batholith of California. Because the solid country rock into which magma intrudes is an excellent insulator, cooling of the magma is extremely slow, and intrusive igneous rock is coarse-grained (phaneritic). Intrusive igneous rocks are classified separately from extrusive igneous rocks, generally on the basis of their mineral content. The relative amounts of quartz, alkali feldspar, plagioclase, and feldspathoid is particularly important in classifying intrusive igneous rocks. Intrusions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afon Gain
This is a list of rivers of Wales, organised geographically. It is taken anti-clockwise from the Dee Estuary to the M48 Bridge that separates the estuary of the River Wye from the River Severn. Tributaries are listed down the page in an upstream direction, starting with those closest to the sea. The main stem (or principal) river of a catchment is given, left-bank tributaries are indicated by (L), and right-bank tributaries by (R). Note that, in general usage, the 'left (or right) bank of a river' refers to the left (or right) hand bank as seen when looking downstream. Where a named river is formed by the confluence of two differently named rivers, these are labelled as (Ls) and (Rs) for the left and right forks. A prime example is the formation of the River Taff from the Taf Fawr and the Taf Fechan at Cefn Coed-y-cymmer. The list includes more or less every watercourse named on Ordnance Survey mapping and thus many of the main rivers of Wales (as defined by Natural Resources Wa ... [...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), known informally as the CRoW Act or "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 Gloucestershir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freedom To Roam
The freedom to roam, or "everyman's right", is the general public's right to access certain public or privately owned land, lakes, and rivers for recreation and exercise. The right is sometimes called the right of public access to the wilderness or the "right to roam". In Scotland, Finland, Iceland, Norway, Sweden, Estonia, Latvia, Lithuania, Belarus, Austria, Czech Republic and Switzerland, the freedom to roam takes the form of general public rights which are sometimes codified in law. The access is ancient in parts of Northern Europe and has been regarded as sufficiently basic that it was not formalised in law until modern times. However, the right usually does not include any substantial economic exploitation, such as hunting or logging, or disruptive activities, such as making fires and driving offroad vehicles. In countries without such general rights, there may be a network of rights of way, or some nature reserves with footpaths. Europe Nordic countries Ancient traces p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rights Of Way In England And Wales
In England and Wales, other than in the 12 Inner London London boroughs, boroughs and the City of London, the right of way is a legally protected right of the public to pass and re-pass on specific paths. 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 ("right to roam"). Private rights of way or easements also exist (see also Highways in England and Wales). Inner London 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 bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Till
image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is diagnostic of till. image:Glacial till exposed in roadcut-750px.jpg, Glacial till with tufts of grass Till or glacial till is unsorted glacier, glacial sediment. Till is derived from the erosion and entrainment of material by the moving ice of a glacier. It is deposited some distance down-ice to form terminal, lateral, medial and ground moraines. Till is classified into primary deposits, laid down directly by glaciers, and secondary deposits, reworked by fluvial transport and other processes. Description Till is a form of '' glacial drift'', which is rock material transported by a glacier and deposited directly from the ice or from running water emerging from the ice. It is distinguished from other forms of drift in that it is depos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of 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 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 geologic maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineralization (geology)
In geology, mineralization is the deposition of economically important metals in the formation of ore bodies or "lodes" by various process. The first scientific studies of this process took place in the English county of Cornwall by J.W.Henwood FRS and later by R.W. Fox, FRS.Embrey, P. G. and Symes, R. F. ''Minerals of Cornwall and Devon'', London, British Museum of Natural History, 1987. hardback, 0-565-00989-3 paperback. page 14, and bibliography Fox: 135, Henwood: 137/8 The term can also refer to the process by which waterborne minerals, such as calcium carbonate (calcite), iron oxide (hematite or limonite) or silica (quartz), replace organic material within the body of an organism that has died and was buried by sediments. Mineralization may also refer to the product resulting from the process of mineralization. For example, mineralization (the process) may introduce metals (such as iron) into a rock. That rock may then be referred to as possessing iron mineralization. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classified as gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewelry and hardstone carvings, especially in Eurasia. Quartz is the mineral defining the val ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolerite
Diabase (), also called dolerite () or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grained to aphanitic chilled margins which may contain tachylite (dark mafic glass). ''Diabase'' is the preferred name in North America, while ''dolerite'' is the preferred name in the rest of the English-speaking world, where sometimes the name ''diabase'' refers to altered dolerites and basalts. Some geologists prefer to avoid confusion by using the name ''microgabbro''. The name ''diabase'' comes from the French ', and ultimately from the Greek - meaning "act of crossing over, transition". Petrography Diabase normally has a fine but visible texture of euhedral lath-shaped plagioclase crystals (62%) set in a finer matrix of clinopyroxene, typically augite (20–29%), with minor olivine (3% up to 12% in olivine diabase), magnetite (2%), and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyke (geology)
A dike or dyke, in geological usage, is a sheet of rock that is formed in a fracture of a pre-existing rock body. Dikes can be either magmatic or sedimentary in origin. Magmatic dikes form when magma flows into a crack then solidifies as a sheet intrusion, either cutting across layers of rock or through a contiguous mass of rock. Clastic dikes are formed when sediment fills a pre-existing crack.Essentials of Geology, 3rd Ed, Stephen Marshak Magmatic dikes A magmatic dike is a sheet of igneous rock that cuts across older rock beds. It is formed when magma fills a fracture in the older beds and then cools and solidifies. The dike rock is usually more resistant to weathering than the surrounding rock, so that erosion exposes the dike as a natural wall or ridge. It is from these natural walls that dikes get their name. Dikes preserve a record of the fissures through which most mafic magma (fluid magma low in silica) reaches the surface. They are studied by geologists for the clue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
