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Inlier
An inlier is an area of older rock (geology), rocks surrounded by younger rocks. Inliers are typically formed by the erosion of overlying younger rocks to reveal a limited outcrop, exposure of the older underlying rocks. Fault (geology), Faulting or fold (geology), 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 (geology), window. Conversely an outlier is an area of younger rock surrounded by older rocks. An outlier is typical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pen Cerrig-calch
Pen Cerrig-calch is a subsidiary summit of Waun Fach in the Black Mountains in the Brecon Beacons National Park in southern Powys, Wales. Its summit, at a height of 701 m (2,300 ft), is marked by a trig point. The peak sits high above the River Usk valley as it narrows above the small town of Crickhowell. The views from here are wide-ranging and extend as far as the Beacons themselves to the west. A ridge runs off to the northwest and the shoulder of Pen Gloch-y-pibwr then turns north to the secondary top of Pen Allt-mawr whose peak at 719m is also crowned by a trig point. Geology Like all of the hills in the Black Mountains, Pen Cerrig-calch is formed from mudstones and sandstones of the Old Red Sandstone laid down during the Devonian period but it is unusual in having a band of Carboniferous Limestone outcropping around the summit and giving rise to a few shakeholes. A classic example of an outlier, the name of the hill reflects this situation; it means 'top of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Usk Inlier
The Usk Inlier is a domed outcrop of rock strata of Silurian age in Monmouthshire in south-eastern Wales. It is located in the countryside between the towns of Caerleon and Pontypool and the village of Raglan. The longer axis of the dome or ' pericline', often referred to as the Usk Anticline, is aligned north–south. The inlier is largely surrounded by a sequence of Old Red Sandstone rocks of Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ... age, though both these and the Silurian rocks are largely obscured by superficial deposits.British Geological Survey 1:50,000 scale geological map sheets 232, 233, 249 & 250 (England & Wales series) References Anticlines Landforms of Monmouthshire Geology of Wales Rock formations of Wales {{Wales-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock (geology)
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition, and the way in which it is formed. Rocks form the Earth's outer solid layer, the crust, and most of its interior, except for the liquid outer core and pockets of magma in the asthenosphere. The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy. It may be limited to rocks found on Earth, or it may include planetary geology that studies the rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments, which in turn are formed by the weathering, transport, and deposition of existing ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust Fault
A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. If the angle of the fault plane is lower (often less than 15 degrees from the horizontal) and the displacement of the overlying block is large (often in the kilometer range) the fault is called an ''overthrust'' or ''overthrust fault''. Erosion can remove part of the overlying block, creating a ''fenster'' (or ''window'') – when the underlying block is exposed only in a relatively small area. When erosion removes most of the overlying block, leaving island-like remnants resting on the lower block, the remnants are called ''klippen'' (singular ''klippe''). Blind thrust faults If the fault plane terminates before it reaches the Earth's surface, it is referred to as a ''blind thrust'' fault. Because of the lack of surface evidence, blind thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for limes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wales
Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in 2021 of 3,107,500 and has a total area of . Wales has over of coastline and is largely mountainous with its higher peaks in the north and central areas, including Snowdon (), its highest summit. The country lies within the Temperateness, north temperate zone and has a changeable, maritime climate. The capital and largest city is Cardiff. Welsh national identity emerged among the Celtic Britons after the Roman withdrawal from Britain in the 5th century, and Wales was formed as a Kingdom of Wales, kingdom under Gruffydd ap Llywelyn in 1055. Wales is regarded as one of the Celtic nations. The Conquest of Wales by Edward I, conquest of Wales by Edward I of England was completed by 1283, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Mountains, Wales
The Black Mountains ( cy, Y Mynydd Du or sometimes ) are a group of hills spread across parts of Powys and Monmouthshire in southeast Wales, and extending across the England–Wales border into Herefordshire. They are the easternmost of the four ranges of hills that comprise the Brecon Beacons National Park, and are frequently confused with the westernmost, which is known as the Black Mountain. The Black Mountains may be roughly defined as those hills contained within a triangle defined by the towns of Abergavenny in the southeast, Hay-on-Wye in the north and the village of Llangors in the west. Other gateway towns to the Black Mountains include Talgarth and Crickhowell. The range of hills is well known to walkers and ramblers for the ease of access and views from the many ridge trails, such as that on the Black Hill (Herefordshire) at the eastern edge of the massif. The range includes the highest public road in Wales at Gospel Pass, and the highest point in southern England ... [...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] |
Carboniferous
The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carboniferous'' means "coal-bearing", from the Latin '' carbō'' ("coal") and '' ferō'' ("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 and William Phillips in 1822, based on a study of the British rock succession. The Carboniferous is often treated in North America as two geological periods, the earlier Mississippian and the later Pennsylvanian. Terrestrial animal life was well established by the Carboniferous Period. Tetrapods (four limbed vertebrates), which had originated from lobe-finned fish during the preceding Devonian, became pentadactylous in and diversified during the Carboniferous, including early amphibian line ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheshire Basin
The Cheshire Basin is a late Palaeozoic and Mesozoic sedimentary basin extending under most of the county of Cheshire in northwest England. It extends northwards into the Manchester area and south into Shropshire. The basin possesses something of the character of a half-graben as its deepest extent is along its eastern and southeastern margins, where it is well defined by a series of sub-parallel faults, most important of which is the Red Rock Fault. These faults divide the basin from the older Carboniferous rocks of the Peak District and the North Staffordshire Coalfield. In terms of its architecture, the basin is sometimes considered to be divided into two sub-basins: the more southerly Wem–Audlem Sub-basin and the Sandbach–Knutsford Sub-basin to its northeast. The basin fill is mainly Permian and Triassic sandstones and mudstones, but it also incorporates economically important halite beds. The sequences referred to the Sherwood Sandstone Group and the overlying Mercia M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
English Midlands
The Midlands (also referred to as Central England) are a part of England that broadly correspond to the Kingdom of Mercia of the Early Middle Ages, bordered by Wales, Northern England and Southern England. The Midlands were important in the Industrial Revolution of the 18th and 19th centuries. They are split into the West Midlands and East Midlands. The region's biggest city, Birmingham often considered the social, cultural, financial and commercial centre of the Midlands, is the second-largest city and metropolitan area in the United Kingdom. Symbolism A saltire (diagonal cross) may have been used as a symbol of Mercia as early as the reign of Offa. By the 13th century, the saltire had become the attributed arms of the Kingdom of Mercia. The arms are blazoned ''Azure, a saltire Or'', meaning a gold (or yellow) saltire on a blue field. The saltire is used as both a flag and a coat of arms. As a flag, it is flown from Tamworth Castle, the ancient seat of the Mercian Kings, to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leek, Staffordshire
Leek is a market town and civil parishes in England, civil parish in the county of Staffordshire, England, on the River Churnet. It is situated about north east of Stoke-on-Trent. It is an ancient borough and was granted its royal charter in 1214. It is the administrative centre for the Staffordshire Moorlands District Council. John of England, King John granted Ranulph de Blondeville, 6th Earl of Chester, the right to hold a weekly Wednesday market and an annual seven-day fair in Leek in 1207. Leek's coat of arms is made up of a saltire shield. On the top is the Stafford knot, either side is the Leek double sunset and below a gold garb. The crest is a mural crown with three mulberry leaves on a mount of heather on top of which a Red grouse, moorcock is resting his claw on a small-weave shuttle. The motto translates to: Our skill assisting us, we have no cause for despair. Economy The town had a regular cattle market for hundreds of years, reflecting its role as a centre of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
