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Partnach Formation
The Partnach Formation is a Middle Triassic geologic formation in the eastern Northern Limestone Alps and Western Carpathians, within Austria and Slovakia, Central Europe. Google Books: ''The Geology of Central Europe: Mesozoic and Cenozoic'' edited by Tom McCann; pgs. 790-795. The formation consists of alternating grey and green s and s (Partnach shales) and grey limestones (Partnach Limestone), often ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Formation
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by Abraham Gottlob Wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slovakia
Slovakia (; sk, Slovensko ), officially the Slovak Republic ( sk, Slovenská republika, links=no ), is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the southwest, and the Czech Republic to the northwest. Slovakia's mostly mountainous territory spans about , with a population of over 5.4 million. The capital and largest city is Bratislava, while the second largest city is Košice. The Slavs arrived in the territory of present-day Slovakia in the fifth and sixth centuries. In the seventh century, they played a significant role in the creation of Samo's Empire. In the ninth century, they established the Principality of Nitra, which was later conquered by the Principality of Moravia to establish Great Moravia. In the 10th century, after the dissolution of Great Moravia, the territory was integrated into the Principality of Hungary, which then became the Kingdom of Hungary in 1000. In 1241 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lariosaurus
''Lariosaurus'' is an extinct genus of nothosaurid from the Middle Triassic (late Anisian to late Ladinian stage) of central and western Europe and China. With a length of just , it was one of the smallest known nothosaurs. First discovered at Perledo on the Lake Como in 1830, it was named in 1847 by Curioni, its name meaning "Lizard from Larius", the ancient name of the lake. This makes it one of the earliest studied reptiles from the Alps. It is known from an almost complete skeleton holotype and several other fairly complete fossils. The nothosaur ''Eupodosaurus'', initially classified as a stegosaurian dinosaur, is now considered synonymous with ''Lariosaurus''. In 1998 Rieppel synonymised ''Lariosaurus, Silvestrosaurus'' and ''Ceresiosaurus,'' but this is disputed by many authors and they are usually considered close relatives. Features For a nothosaur, ''Lariosaurus'' was primitive, possessing a short neck and small flippers in comparison to its relatives. This would ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sauropterygia
Sauropterygia ("lizard flippers") is an extinct taxon of diverse, aquatic reptiles that developed from terrestrial ancestors soon after the end-Permian extinction and flourished during the Triassic before all except for the Plesiosauria became extinct at the end of that period. The plesiosaurs would continue to diversify until the end of the Mesozoic. Sauropterygians are united by a radical adaptation of their pectoral girdle, adapted to support powerful flipper strokes. Some later sauropterygians, such as the pliosaurs, developed a similar mechanism in their pelvis. Uniquely among reptiles, sauropterygians moved their tail vertically like modern cetaceans and sirenians. Origins and evolution The earliest sauropterygians appeared about 247 million years ago (Ma), at the start of the Middle Triassic: the first definite sauropterygian with exact stratigraphic datum lies within the Spathian division of the Olenekian era in South China. Early examples were small (around 60 c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Period (geology)
The geologic time scale, or geological time scale, (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronology (scientific branch of geology that aims to determine the age of rocks). It is used primarily by Earth scientists (including geologists, paleontologists, geophysicists, geochemists, and paleoclimatologists) to describe the timing and relationships of events in geologic history. The time scale has been developed through the study of rock layers and the observation of their relationships and identifying features such as lithologies, paleomagnetic properties, and fossils. The definition of standardized international units of geologic time is the responsibility of the International Commission on Stratigraphy (ICS), a constituent body of the International Union of Geological Sciences (IUGS), whose primary objective is to precisely define ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triassic
The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terrestrial vertebrates during this time. A specialized subgroup of archo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epoch (geology)
The geologic time scale, or geological time scale, (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronology (scientific branch of geology that aims to determine the age of rocks). It is used primarily by Earth scientists (including geologists, paleontologists, geophysicists, geochemists, and paleoclimatologists) to describe the timing and relationships of events in geologic history. The time scale has been developed through the study of rock layers and the observation of their relationships and identifying features such as lithologies, paleomagnetic properties, and fossils. The definition of standardized international units of geologic time is the responsibility of the International Commission on Stratigraphy (ICS), a constituent body of the International Union of Geological Sciences (IUGS), whose primary objective is to precisely define gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossils
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolute ... [...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] |
Lunz Formation
The Lunz Formation is a geologic formation in Austria and other Tethyan regions. It is composed of quartz sandstone, shales and claystones, locally with coal interbeds. The basal part of the formation may contain marine fossils. It preserves fossils dating back to the Carnian stage of the Triassic period and represents significant siliciclastic input into the European carbonate shelf due to the Carnian Pluvial Event.Kohút, M., Hofmann, M., Gavrila, M., Linnemann, U., Havrila, J., 2017: Tracking an upper limit of the “Carnian Crisis” and/or Carnian stage in the Western Carpathians (Slovakia). Int. J. Earth Sci. (Geol Rundsch), DOI: 10.1007/s00531-017-1491-8 Formation is traditionally divided into 3 members (Lunz Sandstone, Coal-bearing shales and Upper Sandstone), this concept was later modified and Trachyceras Beds and Reingraben shales were included into the basal part of the formation: * Trahyceras Beds (Trachycerasschichten, Aonschichten) represented by dark, often bitumin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intraclasts
Intraclasts are irregularly shaped grains that form by syndepositional erosion of partially lithified sediment. Gravel grade material is generally composed of whole disarticulated or broken skeletal fragments together with sand grade material of whole, disaggregated and broken skeletal debris. Such sediments can contain fragments of early cemented limestones of local origin which are known as intraclasts. The sediments that contain fragments of early cemented limestones of extra-basinal origin are called extraclasts. Examples of intraclasts include mudlumps that are torn up from the bottoms of lagoons during storms, hardened desiccated mudflakes produced in intertidal and supratidal environments and fragments broken from cemented deep-sea crusts. Other intraclasts are aggregates of carbonate particles. These include grapestones and botryoidal A botryoidal ( ) texture or mineral habit, is one in which the mineral has an external form composed of many rounded segments, named for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oncolite
Oncolites are sedimentary structures composed of oncoids, which are layered structures formed by cyanobacterial growth. Oncolites are very similar to stromatolites, but, instead of forming columns, they form approximately spherical structures. The oncoids often form around a central nucleus, such as a shell fragment, and a calcium carbonate structure is deposited by encrusting microbes. Oncolites are indicators of warm waters in the photic zone, but are also known in contemporary freshwater environments. These structures rarely exceed 10 cm in diameter. Oncolites may have either a porostromate or spongiostromate texture. Most oncolites are spongiostromate, having no recognisable cellular texture or microstructure. Porostromate oncolites are mostly unknown during the Precambrian; since the Eocene they have mostly been confined to freshwater environments. Distribution The appearance of recent or near-recent freshwater oncoids has been documented in two rivers in Bavaria: th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
