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Kerrera
Kerrera (; gd, Cearara or ''Cearrara'') is an island in the Scottish Inner Hebrides, close to the town of Oban. In 2016 it had a population of 45, divided into two communities in the north and south of the island. Geology The oldest bedrock of Kerrera is black slate ascribed to the Easdale Subgroup of the Dalradian Argyll Group. Overlying this across half of the island are conglomeratic sandstones and basalt and augite-andesite lavas of early Devonian age, the former being the local representative of the Old Red Sandstone and the latter constituting part of the Lorne Plateau Lavas. Ripple marks and sun cracks are preserved in shale strata on the south coast, belying the subaerial environment in which deposition of these sediments took place. There are thin limestones within both the Easdale Slate Formation and the younger sandstones. All of these strata are cut by NW-SE aligned igneous dykes forming part of the North Britain Palaeogene Dyke Suite associated with early P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Old Red Sandstone
The Old Red Sandstone is an assemblage of rocks in the North Atlantic region largely of Devonian age. It extends in the east across Great Britain, Ireland and Norway, and in the west along the northeastern seaboard of North America. It also extends northwards into Greenland and Svalbard. These areas were a part of the ancient continent of Euramerica, Euramerica/Laurussia. In Britain it is a lithostratigraphy, lithostratigraphic unit (a sequence of rock strata) to which Stratigraphy, stratigraphers accord Geological unit#Lithostratigraphic units, supergroup status and which is of considerable importance to early paleontology. For convenience the short version of the term, ORS is often used in literature on the subject. The term was coined to distinguish the sequence from the younger New Red Sandstone which also occurs widely throughout Britain. Sedimentology The Old Red Sandstone describes a suite of sedimentary rocks deposited in a variety of environments during the Devonian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oban
Oban ( ; ' in Scottish Gaelic meaning ''The Little Bay'') is a resort town within the Argyll and Bute council area of Scotland. Despite its small size, it is the largest town between Helensburgh and Fort William. During the tourist season, the town can have a temporary population of up to over 24,000 people. Oban occupies a setting in the Firth of Lorn. The bay forms a near perfect horseshoe, protected by the island of Kerrera; and beyond Kerrera, the Isle of Mull. To the north, is the long low island of Lismore and the mountains of Morvern and Ardgour. Pre-history and archaeology Humans have used the site where Oban now stands since at least Mesolithic times, as evidenced by archaeological remains of cave dwellers found in the town. Just outside the town, stands Dunollie Castle, on a site that overlooks the main entrance to the bay and has been fortified since the Bronze Age. Just to the north of Oban, at Dunstaffnage, excavations in 2010, by Argyll Archaeology, in advanc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gylen Castle
Gylen Castle is a ruined castle, or tower house, at the south end of the island of Kerrera in Argyll and Bute, Scotland, on a promontory overlooking the Firth of Lorne. It was made a scheduled monument in 1931. History Built in 1582 by the Clan MacDougall. Gylen was only occupied for a relatively short time. The castle was besieged then burned by the Covenanters under General Leslie in 1647 during the Wars of the Three Kingdoms. In May 2006 extensive conservation of the castle was completed with a £300,000 grant by Historic Scotland and £200,000 raised by worldwide members of Clan MacDougall Clan MacDougall is a Highland Scottish clan, historically based in and around Argyll. The Lord Lyon King of Arms, the Scottish official with responsibility for regulating heraldry in Scotland, issuing new grants of coats of arms, and serving as .... References External links * Castles in Argyll and Bute Clan MacDougall Scheduled Ancient Monuments in Argyll and Bute Tower hou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argyll And Bute
Argyll and Bute ( sco, Argyll an Buit; gd, Earra-Ghàidheal agus Bòd, ) is one of 32 unitary authority council areas in Scotland and a lieutenancy area. The current lord-lieutenant for Argyll and Bute is Jane Margaret MacLeod (14 July 2020). The administrative centre for the council area is in Lochgilphead at Kilmory Castle, a 19th-century Gothic Revival building and estate. The current council leader is Robin Currie, a councillor for Kintyre and the Islands. Description Argyll and Bute covers the second-largest administrative area of any Scottish council. The council area adjoins those of Highland, Perth and Kinross, Stirling and West Dunbartonshire. Its border runs through Loch Lomond. The present council area was created in 1996, when it was carved out of the Strathclyde region, which was a two-tier local government region of 19 districts, created in 1975. Argyll and Bute merged the existing Argyll and Bute district and one ward of the Dumbarton district. The Dumbart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lorne Plateau Lavas
The Lorne plateau lavas are basaltic lava flows extruded in the late Silurian, 424 to 415 million years ago, which are found today in the Oban - Kerrera area of Scotland. Peperite occurs where they flowed into Old Red Sandstone The Old Red Sandstone is an assemblage of rocks in the North Atlantic region largely of Devonian age. It extends in the east across Great Britain, Ireland and Norway, and in the west along the northeastern seaboard of North America. It also exte ... lakes. References Volcanism of Scotland Lava flows Silurian volcanism {{UK-geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raised Beach
A raised beach, coastal terrace,Pinter, N (2010): 'Coastal Terraces, Sealevel, and Active Tectonics' (educational exercise), from 2/04/2011/ref> or perched coastline is a relatively flat, horizontal or gently inclined surface of marine origin,Pirazzoli, PA (2005a): 'Marine Terraces', in Schwartz, ML (ed) ''Encyclopedia of Coastal Science.'' Springer, Dordrecht, pp. 632–633 mostly an old abrasion platform which has been lifted out of the sphere of wave activity (sometimes called "tread"). Thus, it lies above or under the current sea level, depending on the time of its formation.Strahler AH; Strahler AN (2005): ''Physische Geographie.'' Ulmer, Stuttgart, 686 p.Leser, H (ed)(2005): ‚''Wörterbuch Allgemeine Geographie.'' Westermann&Deutscher Taschenbuch Verlag, Braunschweig, 1119 p. It is bounded by a steeper ascending slope on the landward side and a steeper descending slope on the seaward side (sometimes called "riser"). Due to its generally flat shape, it is often used for a ... [...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] |
Volcanism
Volcanism, vulcanism or volcanicity is the phenomenon of eruption of molten rock (magma) onto the surface of the Earth or a solid-surface planet or moon, where lava, pyroclastics, and volcanic gases erupt through a break in the surface called a vent. It includes all phenomena resulting from and causing magma within the crust or mantle of the body, to rise through the crust and form volcanic rocks on the surface. Magmas, that reach the surface and solidify, form extrusive landforms. Volcanic processes Magma from the mantle or lower crust rises through the crust towards the surface. If magma reaches the surface, its behavior depends on the viscosity of the molten constituent rock. Viscous (thick) magma produces volcanoes characterised by explosive eruptions, while non-viscous (runny) magma produce volcanoes characterised by effusive eruptions pouring large amounts of lava onto the surface. In some cases, rising magma can cool and solidify without reaching the surface. Inste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeogene
The Paleogene ( ; also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period million years ago ( Mya) to the beginning of the Neogene Period Mya. It is the beginning of the Cenozoic Era of the present Phanerozoic Eon. The earlier term Tertiary Period was used to define the span of time now covered by the Paleogene Period and subsequent Neogene Period; despite no longer being recognised as a formal stratigraphic term, 'Tertiary' is still widely found in earth science literature and remains in informal use. Paleogene is often abbreviated "Pg" (but the United States Geological Survey uses the abbreviation PE for the Paleogene on the Survey's geologic maps). During the Paleogene, mammals diversified from relatively small, simple forms into a large group of diverse animals in the wake of the Cretaceous–Paleogene extinction event that ended the preceding C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Atlantic Igneous Province
The North Atlantic Igneous Province (NAIP) is a large igneous province in the North Atlantic, centered on Iceland. In the Paleogene, the province formed the Thulean Plateau, a large basaltic lava plain, which extended over at least in area and in volume. The plateau was broken up during the opening of the North Atlantic Ocean leaving remnants preserved in north Ireland, west Scotland, the Faroe Islands, northwest Iceland, east Greenland, western Norway and many of the islands located in the north eastern portion of the North Atlantic Ocean. The igneous province is the origin of the Giant's Causeway and Fingal's Cave. The province is also known as Brito–Arctic province (also known as the North Atlantic Tertiary Volcanic Province) and the portion of the province in the British Isles is also called the British Tertiary Volcanic Province or British Tertiary Igneous Province. Formation Isotopic dating indicates the most active magmatic phase of the NAIP was between and c. 54.5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dike (geology)
A dike or dyke, in Geology, geological usage, is a sheet of rock that is formed in a Fracture (geology), fracture of a pre-existing rock body. Dikes can be either Intrusive rock, magmatic or Sedimentary rock, 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) reac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Igneous
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava. The magma can be derived from partial melts of existing rocks in either a planet's mantle or crust. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form natural glasses. Igneous rocks occur in a wide range of geological settings: shields, platforms, orogens, basins, large igneous provinces, extended crust and oceanic crust. Geological significance Igneous and metamorphic rocks make up 90–95% of the top ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
