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Clwydian Hills
The Clwydian Range (; also Clwydian Hills or Clwyds) is a series of hills in the north-east of Wales that runs from Llandegla in the south to Prestatyn in the north; the highest point is Moel Famau. The range forms the north-western part of the Clwydian Range and Dee Valley Area of Outstanding Natural Beauty. Geology The Clwydian Hills are formed from an upstanding block of deep sea sediments formed during the Silurian period as debris slurries originating on the nearby continental shelf. The older mudstones and siltstones of the Nantglyn Flags Formation form parts of the west-facing scarp slope and the overlying Elwy Formation, which consists of mudstones and siltstones deposited in deep marine conditions with numerous sandstone beds, forms most of the higher ground. Both formations are of Ludlovian age. The range's rocks are intensely faulted; the major Vale of Clwyd Fault is responsible for the impressive west-facing scarp of the Clwydian Range. It downthrows the roc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liverpool Bay
Liverpool Bay is a bay of the Irish Sea between northeast Wales, Cheshire, Lancashire and Merseyside to the east of the Irish Sea. The bay is a classic example of a region of freshwater influence. Liverpool Bay has historically suffered from reduced oxygen content from prior massive discharges of sewage sludge, according to C. Michael Hogan. The rivers River Alt, Alt, River Clwyd, Clwyd, River Dee, Wales, Dee, River Ribble, Ribble and River Mersey, Mersey drain into the bay. The bay is littered with wrecks and has many Recreational diving, dive sites. The bay also contains several oil and gas fields including the Douglas Complex, with a combined daily capacity (January 2008) of 60,000 Barrel of oil equivalent, barrels. The UK's first major offshore wind farm, North Hoyle, is located in the south of the bay, which is a busy shipping route to the :Mersey docks, Mersey Docks. The land area around the bay is occasionally referred to as the "Liverpool Bay Area". Though the term ... [...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. 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 as grains 2–62 μm in diam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheshire Plain
The Cheshire Plain is a relatively flat expanse of lowland within the county of Cheshire in North West England but extending south into Shropshire. It extends from the Mersey Valley in the north to the Shropshire Hills in the south, bounded by the hills of North Wales to the west and the foothills of the Pennines to the north-east. The Wirral Peninsula lies to the north-west whilst the plain merges with the West Lancashire Coastal Plain, South Lancashire Plain in the embayment occupied by Manchester to the north. In detail, the plain comprises two areas with distinct characters, the one to the west of the Mid Cheshire Ridge and the other, larger part, to its east. The plain is the surface expression of the Cheshire Basin, a deep sedimentary basin that extends north into Lancashire and south into Shropshire. It assumed its current form as the ice-sheets of the last glacial period melted away between 20,000 and 15,000 years ago leaving behind a thick cover of glacial till and exten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snowdonia
Snowdonia, or Eryri (), is a mountainous region and National parks of the United Kingdom, national park in North Wales. It contains all 15 mountains in Wales Welsh 3000s, over 3000 feet high, including the country's highest, Snowdon (), which is tall. These peaks are all part of the Snowdon Massif, Snowdon, Glyderau, and Carneddau ranges in the north of the region. The shorter Moelwynion and Moel Hebog ranges lie immediately to the south. The national park has an area of (the fourth-largest in the UK), and covers most of central and southern Gwynedd and the western part of Conwy County Borough. This is much larger than the area traditionally considered Snowdonia, and in addition to the five ranges above includes the Rhinogydd, Cadair Idris, and Aran Fawddwy, Aran ranges and the Dyfi hills, Dyfi Hills. It also includes most of the coast between Porthmadog and Aberdyfi. The park was the first of the three national parks of Wales to be designated, in October 1951, and the third i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River Wheeler
The River Wheeler ( Welsh: ''Afon Chwiler'') is a tributary of the River Clwyd in north-east Wales. Rising on the east side of the Clwydian Range, it is a "misfit stream" occupying a deep valley cutting westwards through the range into the Vale of Clwyd. The river enters the Clwyd west of the village of Aberwheeler ( Welsh: ''Aberchwiler''), the name of which signifies "the mouth or confluence of the Wheeler". The river is followed for its entire length by the A541 road running from Mold to Trefnant and was formerly followed by the Mold and Denbigh Junction Railway. Besides Aberchwiler, the river passes through or beside the villages of Nannerch, Afon-wen Afonwen (; ) is a village in Flintshire, Wales. It is situated about from the A55 North Wales Expressway and on the A541 Mold-Denbigh road. At the 2001 Census, the population of Afonwen was included into the civil parish of Caerwys and wa ... and Bodfari. There are numerous workings, both active and abandoned, for sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meltwater Channel
A meltwater channel (or sometimes a glacial meltwater channel) is a channel cut into ice, bedrock or unconsolidated deposits by the flow of water derived from the melting of a glacier or ice-sheet. The channel may form on the surface of, within, beneath, along the margins of or downstream from the ice mass. Accordingly it would be referred to as supraglacial, englacial, subglacial, lateral (or ice-marginal) or proglacial. Different forms of subglacial channel are described in glaciological literature including Nye or N-channels, Röthlisberger or R-channels and Hooke or H-channels. Tunnel valley is a related term descriptive of subglacial channels. Some examples of tunnel valleys in northwest England have also been described as iceways. The depositional landforms known as kames and eskers may often be found in association with meltwater channels. An urstromtal is a proglacial or ice-marginal channel common in Germany and Poland formed during various of the Pleistocene gla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice-sheet
In glaciology, an ice sheet, also known as a continental glacier, is a mass of glacial ice that covers surrounding terrain and is greater than . The only current ice sheets are the Antarctic ice sheet and the Greenland ice sheet. Ice sheets are bigger than ice shelves or alpine glaciers. Masses of ice covering less than 50,000 km2 are termed an ice cap. An ice cap will typically feed a series of glaciers around its periphery. Although the surface is cold, the base of an ice sheet is generally warmer due to geothermal heat. In places, melting occurs and the melt-water lubricates the ice sheet so that it flows more rapidly. This process produces fast-flowing channels in the ice sheet — these are ice streams. Even stable ice sheets are continually in motion as the ice gradually flows outward from the central plateau, which is the tallest point of the ice sheet, and towards the margins. The ice sheet slope is low around the plateau but increases steeply at the marg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vale Of Clwyd
The Vale of Clwyd () is a tract of low-lying ground in the county of Denbighshire in north-east Wales. The Vale extends south-southwestwards from the coast of the Irish Sea for some 20 miles (about 30 km) forming a triangle of low ground bounded on its eastern side by the well-defined scarp of the Clwydian Range and to the west by numerous low hills. The River Clwyd (Welsh: ) which rises within Clocaenog Forest, southwest of Denbigh, runs the full length of the vale. It is joined by the two major left bank tributaries of the River Clywedog (Welsh: ) and River Elwy (Welsh: ) and the smaller right bank tributary of the River Wheeler (Welsh: ). History Dyffryn Clwyd was a cantref of Medieval Wales, and from 1282 was a marcher lordship. Settlement and administration At its seaward end are the coastal resorts of Kinmel Bay (Welsh: ), Rhyl and Prestatyn whilst the town of Abergele and city of St Asaph (Welsh: ) lie just inland. The other principal towns of the vale are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian
The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the sixth and last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the Perm Governorate, region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the Sauropsida, sauropsids (reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboniferous
The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the Permian Period, Ma. It is the fifth and penultimate period of the Paleozoic era and the fifth period of the Phanerozoic eon (geology), eon. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian (geology), Mississippian and the later Pennsylvanian (geology), Pennsylvanian. The name ''Carboniferous'' means "coal-bearing", from the Latin ("coal") and ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern "system" names, it was coined by geologists William Conybeare (geologist), William Conybeare and William Phillips (geologist), William Phillips in 1822, based on a study of the British rock succession. Carboniferous is the per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Escarpment
An escarpment is a steep slope or long cliff that forms as a result of faulting or erosion and separates two relatively level areas having different elevations. Due to the similarity, the term '' scarp'' may mistakenly be incorrectly used interchangeably with ''escarpment.'' ''Escarpment'' referring to the margin between two landforms, and ''scarp'' referring to a cliff or a steep slope. In this usage an escarpment is a ridge which has a gentle slope on one side and a steep scarp on the other side. More loosely, the term ''scarp'' also describes a zone between a coastal lowland and a continental plateau which shows a marked, abrupt change in elevation caused by coastal erosion at the base of the plateau. Formation and description Scarps are generally formed by one of two processes: either by differential erosion of sedimentary rocks, or by movement of the Earth's crust at a geologic fault. The first process is the more common type: the escarpment is a transition from one seri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
