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Halleberg 01
Halleberg is a table mountain by lake Vänern in Vänersborg Municipality, Västergötland, Sweden. Halleberg, part of which protrudes into Lake Vänern is separated in the south by about wide valley from the adjacent Hunneberg (also a table mountain). The northern part of Halleberg called ''Hallesnipen''. Geology Hallberg has an average height of about above lake Vänern, or above sea level; the highest point is above sea level. Halleberg consists of Cambrian, Ordovician and Permian rocks. The Palaeozoic rocks are deposited directly on the crystalline peneplain bedrock, which in this range consists of göta granite. The Cambrian sedimentary rocks are sandstone and alum shale. The sandstone layer is on average thick. Above this there is then a thick slate which in turn covered by about of alum shale. The Ordovician is represented by a calcareous slate. During the Permian it was pushed into diabase which lays as a protective cover and thus protect the mountain fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halleberg
Halleberg is a table mountain by lake Vänern in Vänersborg Municipality, Västergötland, Sweden. Halleberg, part of which protrudes into Lake Vänern is separated in the south by about wide valley from the adjacent Hunneberg (also a table mountain). The northern part of Halleberg called ''Hallesnipen''. Geology Hallberg has an average height of about above lake Vänern, or above sea level; the highest point is above sea level. Halleberg consists of Cambrian, Ordovician and Permian rocks. The Palaeozoic rocks are deposited directly on the crystalline peneplain bedrock, which in this range consists of göta granite. The Cambrian sedimentary rocks are sandstone and alum shale. The sandstone layer is on average thick. Above this there is then a thick slate which in turn covered by about of alum shale. The Ordovician is represented by a calcareous slate. During the Permian it was pushed into diabase which lays as a protective cover and thus protect the mountain fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alum Shale
The Alum Shale Formation (also known as alum schist and alum slate) is a formation of black shale of Middle Cambrian to Tremadocian (Lower Ordovician) in age found predominantly in southern Scandinavia. It is shale or clay slate containing pyrite. Decomposition of pyrite by weathering forms sulfuric acid, which acts on potash and alumina constituents to form alum, which often occurs as efflorescences on the rock outcrop. As the formation contains kerogen originated from algae, it is also classified as marinite-type oil shale. At the same time it is rich in aromatic hydrocarbon attributed to post-depositional irradiation damage to saturated hydrocarbons, induced by uranium concentration in the shale. Alum shale also contains enhanced levels of radium as a result of uranium decay. Between 1950 and 1989, Sweden used alum shale for the uranium production. See also *Orsten, a lagerstätte A Lagerstätte (, from ''Lager'' 'storage, lair' '' Stätte'' 'place'; plu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Migration Period
The Migration Period was a period in European history marked by large-scale migrations that saw the fall of the Western Roman Empire and subsequent settlement of its former territories by various tribes, and the establishment of the post-Roman kingdoms. The term refers to the important role played by the migration, invasion, and settlement of various tribes, notably the Franks, Goths, Alemanni, Alans, Huns, early Slavs, Pannonian Avars, Magyars, and Bulgars within or into the former Western Empire and Eastern Europe. The period is traditionally taken to have begun in AD 375 (possibly as early as 300) and ended in 568. Various factors contributed to this phenomenon of migration and invasion, and their role and significance are still widely discussed. Historians differ as to the dates for the beginning and ending of the Migration Period. The beginning of the period is widely regarded as the invasion of Europe by the Huns from Asia in about 375 and the ending with the conq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hillfort
A hillfort is a type of earthwork used as a fortified refuge or defended settlement, located to exploit a rise in elevation for defensive advantage. They are typically European and of the Bronze Age or Iron Age. Some were used in the post-Roman period. The fortification usually follows the contours of a hill and consists of one or more lines of earthworks, with stockades or defensive walls, and external ditches. Hillforts developed in the Late Bronze and Early Iron Age, roughly the start of the first millennium BC, and were used in many Celtic areas of central and western Europe until the Roman conquest. Nomenclature The spellings "hill fort", "hill-fort" and "hillfort" are all used in the archaeological literature. The ''Monument Type Thesaurus'' published by the Forum on Information Standards in Heritage lists ''hillfort'' as the preferred term. They all refer to an elevated site with one or more ramparts made of earth, stone and/or wood, with an external ditch. Many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandinavia
Scandinavia; Sámi languages: /. ( ) is a subregion#Europe, subregion in Northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. In English usage, ''Scandinavia'' most commonly refers to Denmark, Norway, and Sweden. It can sometimes also refer more narrowly to the Scandinavian Peninsula (which excludes Denmark but includes part of Finland), or more broadly to include all of Finland, Iceland, and the Faroe Islands. The geography of the region is varied, from the Norwegian fjords in the west and Scandinavian mountains covering parts of Norway and Sweden, to the low and flat areas of Denmark in the south, as well as archipelagos and lakes in the east. Most of the population in the region live in the more temperate southern regions, with the northern parts having long, cold, winters. The region became notable during the Viking Age, when Scandinavian peoples participated in large scale raiding, conquest, colonization and trading mostl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pine
A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accepts 187 species names of pines as current, together with more synonyms. The American Conifer Society (ACS) and the Royal Horticultural Society accept 121 species. Pines are commonly found in the Northern Hemisphere. ''Pine'' may also refer to the lumber derived from pine trees; it is one of the more extensively used types of lumber. The pine family is the largest conifer family and there are currently 818 named cultivars (or trinomials) recognized by the ACS. Description Pine trees are evergreen, coniferous resinous trees (or, rarely, shrubs) growing tall, with the majority of species reaching tall. The smallest are Siberian dwarf pine and Potosi pinyon, and the tallest is an tall ponderosa pine located in southern Oregon's Rogue Riv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spruce
A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfamily Piceoideae. Spruces are large trees, from about 20 to 60 m (about 60–200 ft) tall when mature, and have whorled branches and conical form. They can be distinguished from other members of the pine family by their needles (leaves), which are four-sided and attached singly to small persistent peg-like structures (pulvini or sterigmata) on the branches, and by their cones (without any protruding bracts), which hang downwards after they are pollinated. The needles are shed when 4–10 years old, leaving the branches rough with the retained pegs. In other similar genera, the branches are fairly smooth. Spruce are used as food plants by the larvae of some Lepidoptera (moth and butterfly) species, such as the eastern spruce budwo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthraconite
Anthraconite (also spelled as anthraxonite) or stinkstone is a form of black to grey, bituminous bearing marble, calcite or limestone which produces an unpleasant odour when struck or rubbed. It is thought to have been formed when limestone is deposited under anaerobic Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen." Anaerobic may also refer to: * Anaerobic adhesive, a bonding a ... conditions. Some anthraconite releases enough petroleum when struck, that it may be lit. At least one locality where it is found is in the vicinity of Traverse City, Michigan. References Further reading * 1989. "Origin and usage of the geological terms orsten, stinkstone, and anthraconite." Archives Of Natural History 16, no. 2: 191. Supplemental Index, EBSCOhost (accessed February 5, 2013). Limestone Marble Bitumen-impregnated rocks {{Petrology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
