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Nolton Haven
Nolton Haven is a hamlet halfway along the coast of St Bride's Bay in Pembrokeshire, Wales. It is included within the Pembrokeshire Coast National Park. Together with the larger inland village of Nolton which is about 1 km to the southeast and the village of Roch, Nolton Haven falls within Nolton and Roch community. Amenities The community is little more than a cluster of houses and a pub next to a shingle cove. The Pembrokeshire Coast Path runs through the village. Since May 2012 this route has also formed a part of the Wales Coast Path. An on-road section of route 4 of the National Cycle Network also runs through Nolton Haven. Geology Nolton Haven lies at the westernmost edge of the Pembrokeshire Coalfield. The local rocks which form a partly fault-bound outlier of the main coalfield which lies to the south, are assigned to the Pennant Sandstone Formation. They largely comprise a faulted series of mudstones, siltstones and sandstones with thin and contorted coal seams ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nolton And Roch
Nolton and Roch ( cy, Nolton a'r Garn) is a community in the Hundred of Roose, Pembrokeshire, Wales. The community consists essentially of the villages of Nolton and Roch and a number of hamlets including Cuffern and Druidston. The western part of the community is in the Pembrokeshire Coast National Park. Its population (2001) was 746, increasing to 825 at the 2011 census. Geography The 5 miles (8 km) coastline of the community consists of picturesque cliffs and dunes, and is followed by the Pembrokeshire Coast Path. At the north end is the 2 mile (3 km) long Newgale beach, which is popular for bathing and surfing. The whole coast is underlain with coal measures and was a centre of industry from medieval times until 1905. Nolton Haven, on the border between the two parishes, was a port from which the local anthracite was shipped. The area is now a popular destination for holidaymakers and second-home owners. The community is on the linguistic boundary that exist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inliers And Outliers (geology)
An inlier is an area of older rocks surrounded by younger rocks. Inliers are typically formed by the erosion of overlying younger rocks to reveal a limited exposure of the older underlying rocks. Faulting or folding may also contribute to the observed outcrop pattern. A classic example from Great Britain is that of the inlier of folded Ordovician and Silurian rocks at Horton in Ribblesdale in North Yorkshire which are surrounded by the younger flat-lying Carboniferous Limestone. The location has long been visited by geology students and experts. Another example from South Wales is the Usk Inlier in Monmouthshire where Silurian age rocks are upfolded amidst Old Red Sandstone rocks of Devonian age. A similar outcrop pattern which results from movement on a thrust fault followed by erosion may be termed a window. Conversely an outlier is an area of younger rock surrounded by older rocks. An outlier is typically formed when sufficient erosion of surrounding rocks has taken place to s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beaches Of Pembrokeshire
A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle, pebbles, etc., or biological sources, such as mollusc shells or coralline algae. Sediments settle in different densities and structures, depending on the local wave action and weather, creating different textures, colors and gradients or layers of material. Though some beaches form on inland freshwater locations such as lakes and rivers, most beaches are in coastal areas where wave or current action deposits and reworks sediments. Erosion and changing of beach geologies happens through natural processes, like wave action and extreme weather events. Where wind conditions are correct, beaches can be backed by coastal dunes which offer protection and regeneration for the beach. However, these natural forces have become more extreme due to climate change, permanently altering beaches at very rapid ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variscan Orogeny
The Variscan or Hercynian orogeny was a geologic mountain-building event caused by Late Paleozoic continental collision between Euramerica (Laurussia) and Gondwana to form the supercontinent of Pangaea. Nomenclature The name ''Variscan'', comes from the Medieval Latin name for the district '' Variscia'', the home of a Germanic tribe, the Varisci; Eduard Suess, professor of geology at the University of Vienna, coined the term in 1880. (Variscite, a rare green mineral first discovered in the Vogtland district of Saxony in Germany, which is in the Variscan belt, has the same etymology.) ''Hercynian'', on the other hand, derives from the Hercynian Forest. Both words were descriptive terms of strike directions observed by geologists in the field, ''variscan'' for southwest to northeast, ''hercynian'' for northwest to southeast. The ''variscan'' direction reflected the direction of ancient fold belts cropping out throughout Germany and adjacent countries and the meaning shifted from d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous ( Pennsylvanian) and Permian times. Many significant coal deposits are younger than this and originate from the Mesozoic and Cenozoic eras. Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until the Industrial Revolution. With the invention of the steam engine, coal consumption increased. In 2020, coal supplied about a quarter of the world's primary energy and over a third of its electricity. Some iron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siltstone
Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, pp.381-382 Although its permeability and porosity is relatively low, siltstone is sometimes a tight gas reservoir rock, an unconventional reservoir for natural gas that requires hydraulic fracturing for economic gas production. Siltstone was prized in ancient Egypt for manufacturing statuary and cosmetic palettes. The siltstone quarried at Wadi Hammamat was a hard, fine-grained siltstone that resisted flaking and was almost ideal for such uses. Description There is not complete agreement on the definition of siltstone. One definition is that siltstone is mudrock ( clastic sedimentary rock containing at least 50% clay and silt) in which at least 2/3 of the clay and silt fraction is composed of silt-sized particles. Silt is defined a ... [...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 (parallel layering).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 disting ... [...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] |
Pennant Sandstone
The Pennant Measures is the traditional name for a sequence of sedimentary rocks of the South Wales Coalfield. They were also referred to as the Upper Coal Measures and assigned to the Westphalian 'C' and Westphalian 'D' stages of the Carboniferous Period. The Pennant Measures were divided into the Lower Pennant Measures and the Upper Pennant Measures, differing from the underlying Middle and Lower Coal Measures in being principally of sandstone units – known collectively as the Pennant Sandstone – with mudstone being the subsidiary rock type. Numerous coal seams occur within the Pennant Measures though they are less common than in the underlying Coal Measures.British Geological Survey 1:50,000 map sheet 231 'Merthyr Tydfil' & accompanying memoir. However recent reclassification of the sequence has resulted in the definition by the British Geological Survey of the Pennant Sandstone Formation as a sub-unit of the newly established Warwickshire Group. The formation is recognised ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pembrokeshire Coalfield
The Pembrokeshire Coalfield in West Wales is one of the smallest British coalfields, but continuously worked from the 14th to 20th centuries. The main coalfield extends across south Pembrokeshire from Saundersfoot on Carmarthen Bay westwards to Broad Haven on St Brides Bay. A small detached portion of the field is centred on Newgale on St Brides Bay. The coalfield is in effect the westernmost extension of the South Wales Coalfield though it is separated from the main body of that field by Carmarthen Bay. Seams Coal seams within the Pembrokeshire Coalfield are traditionally referred to as veins. The following sequence is recognised in the west of the district: The Stonepit and Quarry Veins are collectively referred to as the Sibbernock Veins. The sequence from the Three Quarter to the Foot Vein constitutes the Newgale, Simpson and Eweston Coals. In contrast in the centre and east of the district, there are fewer veins in what is a more compressed sequence: * Rock Vein * Timber V ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pembrokeshire
Pembrokeshire ( ; cy, Sir Benfro ) is a Local government in Wales#Principal areas, county in the South West Wales, south-west of Wales. It is bordered by Carmarthenshire to the east, Ceredigion to the northeast, and the rest by sea. The county is home to Pembrokeshire Coast National Park. The Park occupies more than a third of the area of the county and includes the Preseli Hills in the north as well as the Pembrokeshire Coast Path. Historically, mining and fishing were important activities, while industry nowadays is focused on agriculture (86 per cent of land use), oil and gas, and tourism; Pembrokeshire's beaches have won many awards. The county has a diverse geography with a wide range of geological features, habitats and wildlife. Its prehistory and modern history have been extensively studied, from tribal occupation, through Roman times, to Welsh, Irish, Norman, English, Scandinavian and Flemish influences. Pembrokeshire County Council's headquarters are in the county ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saunders_Quarry-1.jpg "Click for more on -> Sandstone")
