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Grampian Group
The Grampian Group is an estimated 9,000 m thick sequence of metamorphosed Neoproterozoic sedimentary rocks that outcrop across the Central Highlands of Scotland, east of the Great Glen. It forms a part of the Dalradian Supergroup. The sequence thickness at any one place is limited to 5km. Stratigraphy The Glenshirra Subgroup is the lowermost (oldest) part of the succession. These rocks reflect deposition within shallow marine and fluvial environments. It is overlain by the thick sequence of proximal and distal turbidites of the Corrieyairack Subgroup which is in turn overlain by the Glen Spean Subgroup reflective of the infilling of the Corrieyairack, Strath Tummel and Cromdale depositional basins. The Bowmore Sandstone of the Highland Border Complex is correlated with the Corrieyairack Subgroup. Rock successions in Shetland and Islay Islay ( ; gd, Ìle, sco, Ila) is the southernmost island of the Inner Hebrides of Scotland. Known as "The Queen of the Hebrides", it lies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group (stratigraphy)
In geology, a group is a lithostratigraphic unit consisting of a series of related formations that have been classified together to form a group. Formations are the fundamental unit of stratigraphy. Groups may sometimes be combined into supergroups. Groups are useful for showing relationships between formations, and they are also useful for small-scale mapping or for studying the stratigraphy of large regions. Geologists exploring a new area have sometimes defined groups when they believe the strata within the groups can be divided into formations during subsequent investigations of the area. It is possible for only some of the strata making up a group to be divided into formations. An example of a group is the Glen Canyon Group, which includes (in ascending order) the Wingate Sandstone, the Moenave Formation, the Kayenta Formation, and the Navajo Sandstone. Each of the formations can be distinguished from its neighbor by its lithology, but all were deposited in the same vast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphism
Metamorphism is the transformation of existing rock (the protolith) to rock with a different mineral composition or texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of chemically active fluids, but the rock remains mostly solid during the transformation. Metamorphism is distinct from weathering or diagenesis, which are changes that take place at or just beneath Earth's surface. Various forms of metamorphism exist, including regional, contact, hydrothermal, shock, and dynamic metamorphism. These differ in the characteristic temperatures, pressures, and rate at which they take place and in the extent to which reactive fluids are involved. Metamorphism occurring at increasing pressure and temperature conditions is known as ''prograde metamorphism'', while decreasing temperature and pressure characterize ''retrograde metamorphism''. Metamorphic petrology is the study of metamorphism. Metamorphic petrologists re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shetland
Shetland, also called the Shetland Islands and formerly Zetland, is a subarctic archipelago in Scotland lying between Orkney, the Faroe Islands and Norway. It is the northernmost region of the United Kingdom. The islands lie about to the northeast of Orkney, from mainland Scotland and west of Norway. They form part of the border between the Atlantic Ocean to the west and the North Sea to the east. Their total area is ,Shetland Islands Council (2012) p. 4 and the population totalled 22,920 in 2019. The islands comprise the Shetland (Scottish Parliament constituency), Shetland constituency of the Scottish Parliament. The local authority, the Shetland Islands Council, is one of the 32 council areas of Scotland. The islands' administrative centre and only burgh is Lerwick, which has been the capital of Shetland since 1708, before which time the capital was Scalloway. The archipelago has an oceanic climate, complex geology, rugged coastline, and many low, rolling hills. The lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Highland Border Complex
Highlands or uplands are areas of high elevation such as a mountainous region, elevated mountainous plateau or high hills. Generally speaking, upland (or uplands) refers to ranges of hills, typically from up to while highland (or highlands) is usually reserved for ranges of low mountains. However, the two terms are sometimes interchangeable. Highlands internationally Probably the best-known area officially or unofficially referred to as ''highlands'' in the Anglosphere is the Scottish Highlands in northern Scotland, the mountainous region north and west of the Highland Boundary Fault. The Highland council area is a local government area in the Scottish Highlands and Britain's largest local government area. Other highland or upland areas reaching 400-500 m or higher in the United Kingdom include the Southern Uplands in Scotland, the Pennines, North York Moors, Dartmoor and Exmoor in England, and the Cambrian Mountains in Wales. Many countries and regions also have areas re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bowmore Sandstone Group
The Bowmore Sandstone Group is a sequence of metasedimentary rocks, dominantly sandstones, of probable Neoproterozoic age. Their outcrop on the island of Islay in the Inner Hebrides The Inner Hebrides (; Scottish Gaelic: ''Na h-Eileanan a-staigh'', "the inner isles") is an archipelago off the west coast of mainland Scotland, to the south east of the Outer Hebrides. Together these two island chains form the Hebrides, whic ... is entirely fault-bounded, between the Loch Gruinart Fault to the west and the Loch Skerrols Shear Zone to the east. References {{Islay Geology of Scotland Islay ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Basin
Sedimentary basins are region-scale depressions of the Earth's crust where subsidence has occurred and a thick sequence of sediments have accumulated to form a large three-dimensional body of sedimentary rock. They form when long-term subsidence creates a regional depression that provides Accommodation (geology), accommodation space for accumulation of sediments. Over millions or tens or hundreds of millions of years the deposition of sediment, primarily gravity-driven transportation of water-borne eroded material, acts to fill the depression. As the sediments are buried, they are subject to increasing pressure and begin the processes of compaction (geology), compaction and lithification that transform them into sedimentary rock. Sedimentary basins are created by deformation of Earth's lithosphere in diverse geological settings, usually as a result of plate tectonics, plate tectonic activity. Mechanisms of crustal deformation that lead to subsidence and sedimentary basin formati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbidite
A turbidite is the geologic deposit of a turbidity current, which is a type of amalgamation of fluidal and sediment gravity flow responsible for distributing vast amounts of clastic sediment into the deep ocean. Sequencing Turbidites were first properly described by Arnold H. Bouma (1962), who studied deepwater sediments and recognized particular "fining-up intervals" within deep water, fine-grained shales, which were anomalous because they started at pebble conglomerates and terminated in shales. This was anomalous because within the deep ocean it had historically been assumed that there was no mechanism by which tractional flow could carry and deposit coarse-grained sediments into the abyssal depths. Bouma cycles begin with an erosional contact of a coarse lower bed of pebble to granule conglomerate in a sandy matrix, and grade up through coarse then medium plane parallel sandstone; through cross-bedded sandstone; rippled cross-bedded sand/silty sand, and finally lami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Glen
The Great Glen ( gd, An Gleann Mòr ), also known as Glen Albyn (from the Gaelic "Glen of Scotland" ) or Glen More (from the Gaelic ), is a glen in Scotland running for from Inverness on the edge of Moray Firth, in an approximately straight line to Fort William at the head of Loch Linnhe. It follows a geological fault known as the Great Glen Fault, and bisects the Scottish Highlands into the Grampian Mountains to the southeast and the Northwest Highlands to the northwest. The glen is a natural travelling route in the Highlands of Scotland, which is used by both the Caledonian Canal and the A82 road, which link the city of Inverness on the northeast coast with Fort William on the west coast. The Invergarry and Fort Augustus Railway was built in 1896 from the southern end of the glen to the southern end of Loch Ness, but was never extended to Inverness. The railway closed in 1947. In 2002, the Great Glen Way was opened. A long-distance route for cyclists, canoeists, and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Rock
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment, and may be composed of geological detritus (minerals) or biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement, which are called agents of denudation. Biological detritus was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies (marine snow). Sedimentation may also occur as dissolved minerals precipitate from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moine Supergroup
The Moine Supergroup is a sequence of Neoproterozoic metamorphic rocks that form the dominant outcrop of the Scottish Highlands between the Moine Thrust Belt to the northwest and the Great Glen Fault to the southeast. The sequence is metasedimentary in nature and was metamorphosed and deformed in a series of tectonic events during the Late Proterozoic and Early Paleozoic. It takes its name from ''A' Mhòine'', a peat bog in northern Sutherland. Distribution The main outcrop of the Moine series lies northwest of the Great Glen Fault, structurally above the Moine Thrust to the west forming what is known as the Northern Highlands Terrane. A smaller area of similar rocks that are correlated with these, outcrop within the 'Grampian Terrane' to the southeast of the Great Glen. Moinian rocks are also recognised on Mull, Orkney and Shetland. Stratigraphy The Moine Supergroup has been subdivided into different groups or divisions. The relationship between individual groups in terms of ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neoproterozoic
The Neoproterozoic Era is the unit of geologic time from 1 billion to 538.8 million years ago. It is the last era of the Precambrian Supereon and the Proterozoic Eon; it is subdivided into the Tonian, Cryogenian, and Ediacaran periods. It is preceded by the Mesoproterozoic Era and succeeded by the Paleozoic Era of the Phanerozoic Eon. The most severe glaciation known in the geologic record occurred during the Cryogenian, when ice sheets may have reached the equator and formed a " Snowball Earth". The earliest fossils of complex multicellular life are found in the Ediacaran Period. These organisms make up the Ediacaran biota, including the oldest definitive animals in the fossil record. According to Rino and co-workers, the sum of the continental crust formed in the Pan-African orogeny and the Grenville orogeny makes the Neoproterozoic the period of Earth's history that has produced most continental crust. Geology At the onset of the Neoproterozoic the supercontine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Appin Group
The Appin Group is a thick sequence of metamorphosed Neoproterozoic sedimentary rocks that outcrop across the Central Highlands of Scotland, east of the Great Glen. It forms a part of the Dalradian Supergroup. It is divided into three subgroups each consisting of multiple named formations. In stratigraphic order i.e. youngest at the top, these are: Blair Atholl Subgroup :Islay Limestone Formation :Mullach Dubh Phyllites Formation :Lismore Limestone Formation :Cuil Bay Slates Formation Ballachulish Subgroup :Appin Phyllite & Limestone Formation :Appin Quartzite Formation :Ballachulish Slate Formation :Ballachulish Limestone Formation Lochaber Subgroup :Leven Schist Formation :Glencoe Quartzite Formation :Binnein Schist Formation :Binnein Quartzite Formation :Eilde Schist Formation :Eilde Quartzite Formation This whole succession reflects alternate periods of deepening and filling of the sedimentary basin Sedimentary basins are region-scale depressions of the Earth's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
