Crag geology. Alfred Wainwright wrote of .

Crag geology. This is the most southerly exposure of the main Coralline Crag outcrop. Current Projects High-pressure experiments in the PTX Laboratory investigating how minerals dissolve in water in the lower crust and upper mantle. For a fuller discussion see the section The Crags of East Anglia' in the previous chapter. Feb 1, 2021 · The small peralkaline microgranite intrusion that forms the island of Ailsa Craig in the Firth of Clyde represents the southern-most intrusion of the British Palaeogene Volcanic Province (BPVP) within Scotland. The yield is typically moderate to low, of the order of 10 l/sec. She has held board or executive positions with numerous industry associations and is a Past President of the Society of Economic Geologists. Please refer to the Geology Crag Noteworthy Boundaries & Sites map and avoid these areas altogether. A crag (sometimes spelled cragg, or in Scotland craig) is a rocky hill or mountain, generally isolated from other high ground. Strictly the name refers only to the rock face looking down upon Easedale Tarn, but Alfred Wainwright applied it to the entire ridge lying between the Easedale and Far Easedale valleys in his Pictorial Guide to the Lakeland Fells Ph. I am particularly interested in using novel techniques on accessory minerals to investigate this important geological boundary The Geological Society and partner organisations are celebrating the unique geo-heritage of the UK and Ireland with a list of 100 Great Geosites, featuring some of the most diverse and beautiful geology in the world. (British Columbia). The Wallace Monument stands on the crag at the right, and the long tail slopes down leftward Salisbury Crags to the left and Arthur's Seat to the right, with their tails sloping east to the right. The granitic rocks of Ailsa Craig, famous for their use in making curling stones, are thought to be the result of fractionation from a mantle-derived basic magma with no crustal Beneath the Crag Group, the Triassic, Jurassic and Cretaceous sediments (approx. At Walton-on-the-Naze the basal Red Crag pebble bed forms a layer up to several centimetres thick at the horizon marking the onset of the Red Crag’s deposition. Student in Geological Sciences, admitted Spring 2020Contact Mail Code 2115 View Full Stanford Profile Provenance of Ice on Greenland during the Mid-Pliocene as a potential analogue for the future state of the ice sheet. The site includes both the partially overgrown exposures seen at Haw Crag Quarry [SD 9135 5640] and the natural outcrops in the vicinity of Haw Crag summit [SD 9134 5648]. A number of sub-drift Access a collection of geology textbooks on Google Drive for educational and reference purposes. Geochemically the rock is peralkaline, and the site is important as rocks of this composition are relatively rare in the noun In geology, certain strata of Pliocene age occurring in the southeastern counties of England. Full details in the JNCC Open Data Policy Bawdsey Cliff, Suffolk [TM 345 385] – [TM 350 390] Highlights The natural coastal cliff section at Bawdsey is the largest and most spectacular section of the Red Crag presently exposed. This, combined with the distinctive summit rocks which provide the alternative name 'The Lion and the Lamb', makes it one of the most recognised hills in the District. 8 million years ago, during the Gelasian Stage. It is the second youngest unit of the Crag Group, a sequence of four geological formations spanning the Pliocene to Lower Pleistocene transition in East Anglia. Geology of Suffolk The geology of Suffolk in eastern England largely consists of a rolling chalk plain overlain in the east by Neogene clays, sands and gravels and isolated areas of Palaeocene sands. Jun 18, 2025 · My research focuses on the tectonics of the western United States, combining techniques from seismology, tectonophysics, paleomagnetism, field geology, gravity, magnetics, and structural geology. Alfred Wainwright wrote of Jan 1, 1988 · A western extension of the Plio-Pleistocene Red/Norwich Crag deposits is described from south-west Suffolk and north-west Essex. Crag definition: steep rugged rock or cliff. Ailsa Craig (/ ˈeɪlsə /; Scottish Gaelic: Creag Ealasaid) is an island of 99 ha (240 acres) in the outer Firth of Clyde, 16 km (81⁄2 nmi) west of mainland Scotland, upon which microgranite has long been quarried to make curling stones. From Castle Rock and Arthur’s Seat to Barn’s Ness and North Berwick, Edinburgh's geological sites have a wealth of fascinating geology and fossils for you. Water quality Biography I specialise in isotopic and geochemical methods applied to metamorphic, igneous and hydrothermal systems. Where else but on theCrag you can search for climbing areas by your preferred rock type? The information presented here was compiled by Dipl. Manning's research interests include water chemistry, thermodynamics, gas chemistry, geochemistry, igneous petrology, and metamorphic petrology. The onset of “modern” plate tectonics on Earth. Geology The main features of interest at Knockan Crag are the geological exposures where the Moine Thrust and the different rock types can clearly be seen. The landscape around Knockan Crag reveals some of the world’s oldest rocks as well as evidence of geological events that shaped the land. candidate, Stanford University‬ - ‪‪Cited by 231‬‬ - ‪structural geology‬ - ‪tectonics‬ - ‪geothermal energy‬ My research takes me all over the world to study the rocks that preserve a record of Earth’s past. 15, JNCC, Peterborough, ISBN 1 86107 469 7. . [1][2] The Coralline Crag Formation is a geological formation in England. CRAG meaning: a high, rough mass of rock that sticks up from the land around it. Knockan Crag: The Moine Thrust Knockan Crag is the easiest place to see the Moine Thrust. The soils formed on areas of limestone, fucoid beds and salterella grits are much richer than those on Moine schists. The Red Crag Formation comprises a basal pebble bed overlain by shelly coarse sands Edinburgh's geology is derived from different kinds of rock, both sedimentary and igneous that has been eroded over time, particularly during the Ice Age. Its age ranges from approximately 4. As providers of tailor-made adventures, we’ve always sought to interweave the why and how into our trips. Located just west of Interstate 5, between the towns of Castella and Dunsmuir, Castle Crags is today a popular tourist stop along the highway. A number of sub-drift Feb 2, 2017 · There are some Coralline Crag localities (for example, Ramsholt Cliff) where the aragonitic corals are preserved in situ within their calcitic bryozoan hosts, but elsewhere the corals have been dissolved to leave conical pits in the surfaces of the bryozoan colonies. Manning is a professor of geology and geochemistry in the Department of Earth, Planetary, and Space Sciences at the University of California, Los Angeles, where he served as department chair between 2009 and 2012. Jan 1, 1983 · Glauconite-coated flints at the base of a recently recognized spread of Crag deposits are thought to have been derived from a formerly more extensive basal Bullhead Bed of the Thanet Beds. Cotton grass at Knockan Crag The plant life of the area is highly influenced by its underlying geology. The facies geometry o… Chapter 11 The Red Crag P Balson Introduction The Red Crag was first identified as a separate part of the 'crag-formation' by Charlesworth (1835) who named it after its characteristic reddish-brown coloration caused by iron oxides in surface exposures. 4 to 0. It is part of the Crag Group, a series of notably marine strata which belong to a period when Britain was connected to continental Europe by the Weald–Artois Jan 1, 1997 · The Red Crag Formation of eastern Suffolk was deposited in structurally controlled basins during the Pre-Ludhamian, Ludhamian and Thurnian stages. As well as its natural beauty, Friars' Crag is known for its literary and artistic The purpose of this report is to describe the geology, mineral resources, and geologic hazards of this 7. British Tertiary Stratigraphy. It is a popular site with visitors and was acquired for the public by the National Trust in the 1920s. Mount Shasta The island of Ailsa Craig, cut in rocks of a small granitic plug of Palaeogene ('Tertiary') age, forms an imposing feature in the approaches to the Firth of Clyde. Deposits within the Crag strata show clearly how the world was gradually cooling ahead of the ice-age, while the uppermost geology in the Suffolk & Essex Coast & Heaths National Landscape, and indeed much of the landscape we see today, has been shaped directly by the ice-age itself. com crag in Geology topic From Longman Dictionary of Contemporary English crag /kræɡ/ noun [countable] a high and very steep rough rock or mass of rocks Examples from the Corpus crag • The alabaster face of Rogal Dorn branded his retinas: a crag of a face, with lush tough lips. Explore the Reserve through the Rock Room, Rock trails and art, or if you are looking to Jan 1, 1983 · Glauconite-coated flints at the base of a recently recognized spread of Crag deposits are thought to have been derived from a formerly more extensive basal Bullhead Bed of the Thanet Beds. No lithological basis has been found for subdividing the Crag into Norwich and Red Crag, although the faunal criteria for separating these two Crags is of chronological significance. The range is bounded on the east by a system of normal faults, which locally produced the escarpment separating the Sierra Nevada fault block from the Owens Valley. Slow cooling of the magma resulted in a concentric zoning of the pluton that is preserved and exposed in the Castle Crags rocks. The Norwich Crag Formation is a stratigraphic unit of the British Pleistocene Epoch. Aug 1, 2025 · Land-form consisting of a small rocky hill (crag) from which extends a tapering ridge of unconsolidated debris (tail). It generally consists of unconsolidated marine sands that may be locally hard and consolidated. Other articles where crag and tail is discussed: roche moutonnée: A crag and tail is distinguished from a roche moutonnée by the presence of an elongate, tapered ridge of till extending downstream. 1 Regional Geology The Sierra Nevada is the largest continuous mountain range in the contiguous United States. Neogene strata are represented by the two basal formations of the Crag Group. The Crag Group collectively records shallow-marine and coastal sedimentation within the western margins of the North Sea Basin (known locally as the Crag Basin). The Crag may form a single groundwater-bearing unit where it is connected to overlying glacial sands. The Owens Valley, formed on the downfaulted east side of the Sierra Nevada boundary fault system, exhibits many SUMMARY Ailsa Craig, a prominent feature in the Firth of Clyde, is formed principally of arfvedsonite-aegirine-microgranite intruded by vertical dyke swarms of tholeiitic to alkaline (crinanitic) olivine-dolerite with basaltic margins. The lime-rich areas consequently support a richer vegetation, including plants such as mountain avens and rock sedge, whilst areas underlain by Moine schists tend to consist In geology terms the difference between crag and rock is that crag is a partially compacted bed of gravel mixed with shells, of the Tertiary age while rock is any natural material with a distinctive composition of minerals. Nov 29, 2008 · A crag and tail is a larger rock mass than a roche moutonnee. S. Topographic relief is significant as the north aspect Daley, B. Click here if you want to learn more about our offering for: Advocacy groups Crag developers and guidebook editors Local businesses such as accommodation, gear shops, and climbing schools Gyms and route setters Gear manufacturers Knockan Crag is situated thirteen miles north of Ullapool and contains the Rock Room – an unattended open air visitor centre with information panels describing the history and geology of the local landscape. Knockan Crag trail Hear pronunciation Press to hear pronunciation Summary This interpretative trail brings the geology of the Moine Thrust to life as the path climbs past the exposed rocks and up onto the top of the Knockan Crag. The Abbey Craig, a crag with tail near the University of Stirling. It is of great ‪Professor of Geological Sciences, University of Colorado at Boulder‬ - ‪‪Cited by 5,913‬‬ - ‪Tectonics‬ - ‪geophysics‬ - ‪geology‬ Jul 13, 2025 · (geology) A partially compacted bed of gravel mixed with shells, of the Pliocene to Pleistocene epochs. Discover expressions like "crag martin". But many people don’t quite grasp how fundamental geology is to creating this incredible landscape. Salisbury Crags are of great significance in the development of modern geology. motive Along the Rock Route and sandwiched between Stac Pollaidh and Elpin is the Knockan Crag visitor centre. - Download This career-long odyssey has led me through the realms both large and small: mesoscopic structural geology, mineralogy and mineral chemistry, regional geology, igneous and metamorphic petrology, igneous geochemistry, tectonics, 40Ar/39Ar, U-Pb, and (U-Th)/He geochronology, and tectonic geomorphology. 1999. This puts all the Crag Group of the present district in the Pleistocene. How this silicic crust Objective description: The focus of our management at Knockan Crag is to protect the geological and upland vegetation (upland assemblage) interests. Craig is within the southeastern portion of the quadrangle. The crag is a residual feature left by selective glacial erosion, while the tail is drift-deposited by ice on the lee side of the obstacle. An example of a crag is a sharp, large rock poking out from a mountain. The trail includes sculptures and poetry as well as places to sit and a treasure hunt for younger children. The Crag as an aquifer The Crag is a locally important aquifer, up to about 80 m thick, found in parts of East Anglia. The facies geometry of these sediments is described, and related to that of the well-exposed Crag sequence of the Suffolk coast. Like a roche moutonnee, it is formed from a section of rock that was more resistant than its surroundings. Only Honister Crag has been worked recently. It is a series of marine deposits found near the North Sea coast of Suffolk and characterised by bryozoan and mollusc debris. of Earth and Planetary Sciences, University of Texas Geology Geology crm7@mit. Crag definition: A steep rugged mass of rock projecting upward or outward. Then, immediately overlying this with a sharp contact, are 4. 65 to 250 million years old) comprise limestones, sandstones and mudstones, comparable to those seen along the coasts of Dorset and North Yorkshire. From here there are spectacular views over Assynt. The now-uninhabited island comprises the remains of a magmatic pluton formed during the same period of igneous activity as magmatic rocks on the nearby Mar 6, 2025 · Geology is one of the reasons why the Northwest Highlands is our favourite part of Scotland. The tail in this type consists of bedrock. The Coralline Crag bryozoan fauna includes another example of a fossil symbiosis. It outcrops in south-eastern Suffolk and north-eastern Essex. Erosional crag-and-tails consist of a highly resistant rock crag that protected less resistant bedrock in its lee from the full force of glacial erosion. Potential graduate students please read this! PROFESSIONAL APPOINTMENTS Assistant Professor, Dept. The Norwich Crag is a marginal facies of the thicker In his research Craig uses paleomagnetism, field-based structural geology, and geochronology to study the development of orogenic belts and plate reorganizations. Geological Conservation Review Series No. Unlock the mysteries of one of the oldest landscapes in Europe. I am particularly focussed on the novel use of accessory minerals, such as zircon, titanite, rutile and apatite, to investigate large-scale problems in Earth Science. The BGS Lexicon of Named Rock Units — Result Details Crag Group Another Query ? See full list on timesmojo. 5-minute quadrangle located near Craig in northwestern Colorado. The Red Crag Formation is a geological formation in England. Despite its low height it sits prominently at the end of a ridge, easily seen from the village. cake. As nouns the difference between crag and rock is that crag is a rocky outcrop while rock is the naturally occurring aggregate of solid mineral matter that constitutes a Sighty Crag is a [hill in the southern part of the Kielder Forest region in northern England, a region which also includes its fellow Marilyns of Peel Fell and Larriston Fells. There is a At Knockan Crag National Nature Reserve, managed by NatureScot, you can see for yourself the marvel that allowed one of the world's greatest geological mysteries to be solved. Introduction The exposure of Coralline Crag on the bank of the I climbed passionately in my 20s and had the joy of my first child when I hit 30, which took climbing out of my regular routine. An example of a crag is an animal’s throat. 'The Cliff', Gedgrave, Suffolk [TM 3972 4863] Highlights The locality at The Cliff', Gedgrave, provides, in a single section, the opportunity to examine the rich shelly fauna of the Ramsholt Member and to see the cross-bedded Sudbourne Member which overlies it. 2011; Lee et al. Crag may refer to: Crag (climbing), a cliff or group of cliffs, in any location, which is or may be suitable for climbing Crag (dice game), a dice game played with three dice Crag, Arizona, US Crag, West Virginia, US Crag and tail, a geological formation caused by the passage of a glacier over an area of hard rock Aug 14, 2019 · The Red Crag Formation hosts sedimentological and ichnological proxies that can be used to assess the time taken to accumulate outcrop expressions of strata, as ancient depositional environments fluctuated between states of deposition, erosion and stasis. Castle Crags is composed of different types of granitic rock, representing different parts of the pluton. Dec 19, 1988 · Home Geology Geoscience Stratigraphy Article PDF Available Stratigraphy and Palaeoenvironments of the Red Crag and Norwich Crag Formations Between Aldeburgh and Sizewell, Suffolk, England December Jul 3, 2019 · Where does the time go? Assessing the chronostratigraphic fidelity of sedimentary rock outcrops in the Pliocene-Pleistocene Red Crag Formation, eastern England If around the existing Crag, these are remnants from when areas were previously used for grazing. Studies of metamorphism of oceanic gabbros from the East Pacific Rise to understand the timing and temperatures of fluid-rock interaction in the lower crust of mid-ocean ridges. Elevations range from 2,000 feet (610 m) along the Sacramento River near the base of the crags, to over 6,500 feet (2,000 m) at the summit of the tallest crag. This document summarizes glacial landforms in the Lake District region near Derwent Water, including drumlins, eskers, and kames. -Geologist Harald Rost She has a Ph. [1][2] A variety of superficial deposits originating in the last couple of million years overlie this 'solid geology'. Resources related to this work can be found through the links at left. The sediments Craig STOREY, Reader in Geology | Cited by 5,456 | of University of Portsmouth, Portsmouth | Read 121 publications | Contact Craig STOREY Jul 7, 2022 · The definition of crag is the neck or throat area, or a rugged rock that sticks out from a mass of rocks. At depth in boreholes and below the water table the Friars' Crag seen from Derwentwater Friars' Crag, [1] sometimes spelled Friar's Crag[2] or Friars Crag, [3] is a promontory overlooking Derwentwater near Keswick, Cumbria, in the English Lake District. 4. The crag is a globally important geological site and was formed by the Moine Thrust, the force of two continents crashing together. At Knockan Crag NNR Scotland’s story of ancient oceans, vast deserts and ice sheets, crashing continents and epic journey from pole to pole is told through poetry The geology of Norfolk in eastern England largely consists of late Mesozoic and Cenozoic sedimentary rocks of marine origin covered by an extensive spread of unconsolidated recent deposits. The highest elevation is Cedar Mountain in […] Jan 1, 2014 · Reviews of the Pliocene and Pleistocene Epochs in East Anglia; reference to the discovery and importance of molluscan shells; account of the Crag beds including the Red Crag, Norwich Crag, Chillesford and Cromer Forest Beds and Weybourne Crag; the Crag Sea and its theCrag offers solutions for stakeholders of the climbing community. It was deposited between approximately 2. The outer part of the magma Knockan Crag is a window into conditions 420 million years ago, at the edge of the Caledonian mountains, demonstrating that how great slabs of rock can be pushed to the surface and sideways over adjacent rocks in ‘thrust sheets’. 3a. The Geological Society and partner organisations are celebrating the unique geo-heritage of the UK and Ireland with a list of 100 Great Geosites, featuring some of the most diverse and beautiful geology in the world. Pre-Ludhamian and Ludhamian Helena Area Geology Helena lies within the Northern Rocky Mountains physiographic province. crag From Longman Dictionary of Contemporary English Related topics: Geography, Geology crag /kræɡ/ noun [countable] a high and very steep rough rock or mass of rocks Examples from the Corpus crag • The alabaster face of Rogal Dorn branded his retinas: a crag of a face, with lush tough lips. The Red Crag Formation is the second oldest unit of the late Cenozoic Crag Group, which crops out in eastern England (McMillan et al. Having worked in Artificial Intelligence research for many years I had fun doing the advanced features but The surface rocks of Essex that were formed before the Ice Age (from the Chalk to the Red Crag) are described as the ‘bedrock’ or ‘solid’ geology. The deposit, whose onshore occurrence is mainly restricted to the area around Aldeburgh and Orford, [1][2] is a series of bioclastic calcarenites and silty sands with shell debris, deposited during a ‪Ph. Above the grey Durness Limestone seen at Skiag Bridge there is a fractured and sheared white limestone. Jonathan CRAIG, Strategic Exploration Advisor | Cited by 3,287 | of Eni SpA, Rome | Read 81 publications | Contact Jonathan CRAIG Earth is unique in our solar system having a bimodal distribution of crust: a basaltic oceanic crust and a more silicic continental crust. Evolution of the continental crust – particularly in the Archaean and Palaeoproterozoic. Geo. In doing so it tries to bridge the gap between the scientific view of a geologist and the information needs of an interested climber. [4] This photogenic landmark, popular with rock climbers, [6] is situated approximately three miles south of the community of Mammoth Lakes, on land managed by Inyo National Forest. The dykes tend to follow the major joint-patterns in the microgranite, with three main distribution modes at the north-west, NNW and north-east. Learn more. The name derives from its iron-stained reddish colour and crag which is an East Anglian word for shells. 1. Much of the recent work has focused on seismological approaches to understanding the mechanism supporting topography in the Sierra Nevada and High Plains, but I have also incorporated observations from other disciplines (gravity, paleoaltimetry, petrology, etc Glaciers sweeping outwards from the centre of Scotland have left a classic crag-and-tail, descending gently towards Arthur's Seat and Whinny Hill in the East. The document also lists references used in the research on the glacial geology of the Lake District, highlighting works from the Cumberland Geological Society. Tarn Crag is a fell in the Central Fells of the English Lake District. & Balson, P. edu 2017 – 2023 Craig Johnson is a Research Geologist with the Geology, Geophysics, and Geochemistry Science Center. The Crag Group is a geological group outcropping in East Anglia, England and adjacent areas of the North Sea. Whereas, crags, while also studied by geologists, often hold more interest for ecologists and environmentalists studying specific habitats and ecosystems. 478 million years BP, spanning the late Pliocene and early to middle Pleistocene epochs. Helm Crag is a fell in the English Lake District situated in the Central Fells to the north of Grasmere. Investigation of the links between fluid flow, mineral reaction, and Castle Crags is a dramatic and well-known rock formation in Northern California. A r… Jan 1, 1988 · A western extension of the Plio-Pleistocene Red/Norwich Crag deposits is described from south-west Suffolk and north-west Essex. Along the southeastern border, the Yampa River winds in and out of this quadrangle. Craig is accepting students for Fall 2025! Our group uses field-based structural geology and geochronology to unravel tectonic events and the uplift of major mountain belts, such as the Himalaya. 4 and 1. A further major problem with correlation of the Crag is the presence of large local breaks in the sequence, now believed to be due to an unconformable relationship between the Norwich Crag and the Red Crag. The slate consists of green, cleaved volcaniclastic rocks of the Eagle Crag Member of the Birker Fell Formation. noun (Geol. Check meanings, examples, usage tips, pronunciation, domains, and related words. The worked area includes three distinct quarry locations, Dubs [NY 210 135], Yew Crag [NY 224 143] and Honister Crag [NY 215 140]. The granitic monolith of Castle Crags is the remnant of a pluton. It is a term frequently encountered in the context of geology, climbing, and outdoor activities. from the GNU version of the Collaborative International Dictionary of English. Crystal Crag is a 10,377-foot-elevation (3,163-meter) summit located in the Sierra Nevada mountain range in Mono County of northern California, United States. noun A steep, rugged rock; a rough, broken cliff, or point of a rock, on a ledge. The word conjures images of formidable, towering rock faces that can be both awe-inspiring and challenging to explore. The same pattern of sedimentation occurs throughout. He has worked on projects in geophysics and seismology, geology, computational fluid dynamics, data science, satellite data, geotechnical engineering and hydrogeology. Much of this bedrock geology is concealed beneath the deposits left behind by glaciers and rivers during the Ice Age. Please be aware that private property lies south just of the Crag and in the case of the south side of the Hillside sector, just over the road. 2015; Mathers & Hamblin 2015) and consists of four discrete transgressive formations (the others, from oldest to youngest, being the Coralline Crag, Norwich Crag and Wroxham Crag formations) (Fig The Red Crag Formation is the second oldest unit of the late Cenozoic Crag Group, which crops out in eastern England (McMillan et al. Quaternary-age sediments (0 to 10,000 years old) up to 6,000 feet thick fill the valley and form a northeast-sloping alluvial plain measuring roughly 64 square miles. degree in geology from the University of Arizona (1990) and is a P. Apr 17, 2024 · The study of rocks is a fundamental aspect of geology, helping scientists understand Earth's history and structure. ) A partially compacted bed of gravel mixed with shells, of the Tertiary age. I manage the Crustal Evolution Research Group at Portsmouth, one of the largest dedicated groups of its kind in Research My main interest is in the origin of mountains and elevated topography in continents, primarily in the western U. Where continents collide Amazing stories stored in the rocks come to life at Knockan Crag National Nature Reserve (NNR) – a visitor attraction in the North West Highlands Geopark – where we guarantee you an earth-moving experience. The Continental Divide, which separates the Columbia and Missouri River drainages, is located 15 miles west of the valley. Knockan Crag NNR – the main event! ///herds. Trondhjemite and granodiorite form a core and shell, respectively. Often produced by selective erosion of softer strata, roche moutonnée landscapes are characteristic of glaciated crystalline shield areas. It’s hard not to get excited about rocks and geology at Knockan Crag. It lies in the Inverpolly Nature Reserve, and a nature trail leads up and along the crag, through the succession of Cambrian sediments. Coincidently my climbing partner, Campbell, also had a child at about the same time, so to keep us connected with the climbing community, we founded theCrag. Ailsa Craig is composed of alkali-microgranite containing the sodic mafic minerals arfvedsonite and aegirine. It notes the exposure of glacial deposits at locations like Friars Crag and Broom Hill Point. The buoyant continental crust, not found on planets of similar bulk composition (Mars, Venus), floats above the oceanic crust, providing an important aspect to plate tectonics and leading to the development of complex life on Earth. Craig E. (uncountable) A game played with three dice, similar to Yahtzee. 2015; Mathers & Hamblin 2015) and consists of four discrete transgressive formations (the others, from oldest to youngest, being the Coralline Crag, Norwich Crag and Wroxham Crag formations) (Fig Usage Notes “Crag” is often used to describe natural rock formations found in mountainous or coastal regions. The following article gives an overview about the many rock types that are out there for climbing. Almscliffe Crag, or Almscliff Crag, also known as Great Almscliff Crag to distinguish it from Little Almscliff, 3 miles (5 km) north west, is a Millstone Grit outcrop at the top of a small hill near the village of North Rigton, between Leeds and Harrogate in North Yorkshire, England. D. Important early works relating to the site geology are by Wilmore (1910), Hudson (1927) and Hudson and Dunnington (1944).