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52-791: The Svecofennian orogeny developed as a succession of four orogenies which by chronological order are: the Lapland-Savo orogeny, the Fennian orogeny, the Svecobaltic orogeny and the Nordic orogeny. In broad terms, regardless of details, it has been proposed that the Svecofennian orogeny involved more-less continuous subduction with subduction zones progressively migrating to the southwest. An alternative model postulates subduction included alternating extension and compression cycles, with

104-401: A conceptual model . In order to execute the model, it needs to be implemented as a computer simulation . This requires more choices, such as numerical approximations or the use of heuristics. Despite all these epistemological and computational constraints, simulation has been recognized as the third pillar of scientific methods: theory building, simulation, and experimentation. A simulation

156-567: A gravitational collapse from 1790 to 1770 million years ago. The late magmatism following the orogeny overlaps in time with the early magmatism of the Transscandinavian Igneous Belt. This magmatism was largely the result of anatexis forming migmatites and large plutons . Another characteristic of the late magmatism is the apparent lack of mafic and intermediate compositions among the magmas, which are nearly all felsic . Geologist Baltybaev (2013) have identified

208-475: A logical and objective way. All models are in simulacra , that is, simplified reflections of reality that, despite being approximations, can be extremely useful. Building and disputing models is fundamental to the scientific enterprise. Complete and true representation may be impossible, but scientific debate often concerns which is the better model for a given task, e.g., which is the more accurate climate model for seasonal forecasting. Attempts to formalize

260-548: A mathematical construct is solely and precisely that it is expected to work—that is, correctly to describe phenomena from a reasonably wide area. There is also an increasing attention to scientific modelling in fields such as science education , philosophy of science , systems theory , and knowledge visualization . There is a growing collection of methods , techniques and meta- theory about all kinds of specialized scientific modelling. A scientific model seeks to represent empirical objects, phenomena, and physical processes in

312-428: A model will deal with only some aspects of the phenomenon in question, and two models of the same phenomenon may be essentially different—that is to say, that the differences between them comprise more than just a simple renaming of components. Such differences may be due to differing requirements of the model's end users, or to conceptual or aesthetic differences among the modelers and to contingent decisions made during

364-419: A perception of reality. This perception is already a model in itself, as it comes with a physical constraint. There are also constraints on what we are able to legally observe with our current tools and methods, and cognitive constraints that limit what we are able to explain with our current theories. This model comprises the concepts, their behavior, and their relations informal form and is often referred to as

416-571: A reorganization of the local plate tectonics . As a consequence the Bergslagen microcontinents collided with the Keitele–Karelia collage starting the Fennian orogeny. The until then linear Fennian orogen was "buckled" from 1870 million years ago onwards due to an orthogonal change in tectonic compressive stress . This resulted in various oroclines around the Gulf of Bothnia . Prior to

468-403: A variety of sources, including from surrounding country rocks (pore water) or from the decomposition of hydrous minerals (e.g. micas, amphiboles). Melting reactions involving water liberated from hydrous minerals are often referred to as dehydration melting reactions or vapour-absent reactions. Over time, dehydration melting reactions will consume all of the hydrous phases in a rock, meaning that

520-674: A very fast coarse model with its related expensive-to-compute fine model so as to avoid direct expensive optimization of the fine model. The alignment process iteratively refines a "mapped" coarse model ( surrogate model ). One application of scientific modelling is the field of modelling and simulation , generally referred to as "M&S". M&S has a spectrum of applications which range from concept development and analysis, through experimentation, measurement, and verification, to disposal analysis. Projects and programs may use hundreds of different simulations, simulators and model analysis tools. The figure shows how modelling and simulation

572-424: Is a fundamental and sometimes intangible notion covering the recognition, observation, nature, and stability of patterns and relationships of entities. From a child's verbal description of a snowflake, to the detailed scientific analysis of the properties of magnetic fields , the concept of structure is an essential foundation of nearly every mode of inquiry and discovery in science, philosophy, and art. A system

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624-747: Is a granitoid region of the Svecofennian orogen completely surrounded by rocks of Transscandinavian Igneous Belt . As the name implies the Oskarshamn-Jönköping belt runs as sliver from the vicinity of Oskarshamn northwest to the Jönköping area. It has been proposed that the Oskarshamn-Jönköping belt continues beneath the East European Platform in Lithuania . The boundary of the Svecofennian orogen with

676-401: Is a set of interacting or interdependent entities, real or abstract, forming an integrated whole. In general, a system is a construct or collection of different elements that together can produce results not obtainable by the elements alone. The concept of an 'integrated whole' can also be stated in terms of a system embodying a set of relationships which are differentiated from relationships of

728-539: Is a way to implement the model, often employed when the model is too complex for the analytical solution. A steady-state simulation provides information about the system at a specific instant in time (usually at equilibrium, if such a state exists). A dynamic simulation provides information over time. A simulation shows how a particular object or phenomenon will behave. Such a simulation can be useful for testing , analysis, or training in those cases where real-world systems or concepts can be represented by models. Structure

780-462: Is either impossible or impractical to create experimental conditions in which scientists can directly measure outcomes. Direct measurement of outcomes under controlled conditions (see Scientific method ) will always be more reliable than modeled estimates of outcomes. Within modeling and simulation , a model is a task-driven, purposeful simplification and abstraction of a perception of reality, shaped by physical, legal, and cognitive constraints. It

832-400: Is evaluated first and foremost by its consistency to empirical data; any model inconsistent with reproducible observations must be modified or rejected. One way to modify the model is by restricting the domain over which it is credited with having high validity. A case in point is Newtonian physics, which is highly useful except for the very small, the very fast, and the very massive phenomena of

884-407: Is promoted. As a rock partially melts and begins to flow, its rheology changes significantly. Such changes will localize the strain created by regional tectonics and as per Le Chatelier's Principle , the system responds by pumping melt towards zones of dilatancy (lower pressure) thereby segregating the melt from its anatectic source on a local scale. Where this has occurred and been preserved in

936-420: Is task-driven because a model is captured with a certain question or task in mind. Simplifications leave all the known and observed entities and their relation out that are not important for the task. Abstraction aggregates information that is important but not needed in the same detail as the object of interest. Both activities, simplification, and abstraction, are done purposefully. However, they are done based on

988-401: Is the partial melting of rocks . Traditionally, anatexis is used specifically to discuss the partial melting of crustal rocks, while the generic term " partial melting " refers to the partial melting of all rocks, in both the crust and mantle . Anatexis can occur in a variety of different settings, from zones of continental collision to mid-ocean ridges . It is believed that anatexis

1040-422: Is the process largely responsible for the formation of migmatites . Furthermore, scientists have recently discovered that partial melting plays an increasingly important role in active crustal processes, including the advancement of active deformation and the emplacement of crustal granites . As a result, active feedback between crustal shearing , melting, and granite emplacement has become largely accepted in

1092-527: Is used as a central part of an integrated program in a defence capability development process. Nowadays there are some 40 magazines about scientific modelling which offer all kinds of international forums. Since the 1960s there is a strongly growing number of books and magazines about specific forms of scientific modelling. There is also a lot of discussion about scientific modelling in the philosophy-of-science literature. A selection: Anatexis Anatexis (via Latin from Greek roots meaning "to melt down")

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1144-461: The principles of the empirical sciences use an interpretation to model reality, in the same way logicians axiomatize the principles of logic . The aim of these attempts is to construct a formal system that will not produce theoretical consequences that are contrary to what is found in reality . Predictions or other statements drawn from such a formal system mirror or map the real world only insofar as these scientific models are true. For

1196-534: The Archean "Kola-Karelian orogen" to the northwest is made up by the Luleå-Kuopio suture zone . The dextral South Finland Shear Zone runs across much of southern Finland in a west–east direction. Cited book Model (science) Scientific modelling is an activity that produces models representing empirical objects, phenomena, and physical processes, to make a particular part or feature of

1248-469: The Earth's geotherm . The amount and composition of partial melts likely varies locally, reflecting the heterogeneity of the Earth's crust. In order to induce crustal melting, the temperature must be increased past the normal geotherm. Possible sources of heat include primordial heat originating from the core of the Earth as well as the decay of radioactive elements . This heat is distributed throughout

1300-412: The Earth's crust by a number of different processes, including radiation , conduction , convection , and advection . The emplacement of magmatic intrusions is also commonly associated with local increases in temperature. If the increase in temperature is sufficient, this can lead to partial melting of adjacent country rocks. If partial melting does occur, then the degree of melting is controlled by

1352-651: The Svecobaltic orogeny proper there was period of northward-directed subduction at what is now south-central Sweden and southern Finland. The subduction lasted from 1860 to 1840 million years ago and was accompanied by magmatic activity . Two trends in the southern Svecofennian orogen variously overlapped in time and space: extension (1870 to 1840 million years ago) and continent-continent collision (1870 to 1790 million years ago). Magmatic activity and metamorphism in southern Finland ended gradually after 1870 million years ago. The orogen at southern Finland with its presumed mountains and thick continental crust collapsed under

1404-466: The advancement of deformation and partial melting is referred to as syntectonic crustal anatexis. Syntectonic anatectic migmatites at Hafafit region, Eastern Desert, Egypt as a part of the Nubian Shield are a good example of such crustal melts. Segregation of granitic melts from their residual solids begins with the onset of partial melting along the grain boundaries of reactant minerals, namely

1456-410: The amount of available heat in the magmatic body. Beneath the Earth's surface, pressure increases with depth due to the accumulation of overlying rock. At a given temperature, a decrease in pressure can result in localized melting. Melting that is caused by a drop in pressure is referred to as decompression melting. Decompression melting can occur in thickened portions of the Earth's crust and may be

1508-440: The amount of melt generated through these reactions is controlled by the abundance and stability of specific hydrous phases. Depending on the tectonic setting, water can also be introduced to the system through the dehydration of a subducting hydrated oceanic plate or magmatic underplating. The composition of a parent rock has a direct effect on the composition of the resulting melt. Granitic melts are commonly classified based on

1560-495: The dawn of man. Examples from history include cave paintings , Egyptian hieroglyphs , Greek geometry , and Leonardo da Vinci 's revolutionary methods of technical drawing for engineering and scientific purposes. Space mapping refers to a methodology that employs a "quasi-global" modelling formulation to link companion "coarse" (ideal or low-fidelity) with "fine" (practical or high-fidelity) models of different complexities. In engineering optimization , space mapping aligns (maps)

1612-555: The domain of application of the model. For example, the special theory of relativity assumes an inertial frame of reference . This assumption was contextualized and further explained by the general theory of relativity . A model makes accurate predictions when its assumptions are valid, and might well not make accurate predictions when its assumptions do not hold. Such assumptions are often the point with which older theories are succeeded by new ones (the general theory of relativity works in non-inertial reference frames as well). A model

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1664-460: The ferromagnesian phases of micas and amphiboles. Such reactions produce large positive volume changes within the metamorphic system causing melt enhanced embrittlement. This, coupled with an increasing melt fraction, alters the deformation mechanisms acting among grains and decreases the strength of the rock significantly. Melt filled pores eventually coalesce and melt flow parallel to the elongation lineation of grains (or along planes of foliation)

1716-553: The following terranes as composing the Svecofennian orogen (parenthesis indicate location): Skellefteå Terrane ( Skellefte River Basin ), Bothnian Terrane ( Västernorrland and Ostrobothnia ), Pyhäsalmi Terrane ( Northern Savonia ), Central Terrane (Central Finland), Western Terrane ( Gävleborg ), Ladoga Terrane (southern Finland–Russia border) and the Southern Terrane ( Bergslagen and Southern Finland). Baltybaev further distinguishes between an outer zone in

1768-455: The formation and development of an interconnected accumulation network. When the transport of melt occurs on larger scales, anatexis can lead to the ascent and emplacement of large granitic bodies in the upper crust. This transition is generally marked by the change from shear-driven melt migration to buoyancy-driven melt migration. This final step in the extraction process requires an optimal balance between melt fraction and melt distribution in

1820-590: The formation of igneous rocks and the emplacement of the Jormua and Outokumpu ophiolites about 1950 million years ago. In the later stages of the Lapland-Savo orogeny an island arc , the Knaften arc, accreted to the Keitele-Karelia-Norrbotten collage . The stage to the Fennian orogeny was set by a collision between Keitele and Karelia about 1920–1910 million years ago which resulted in

1872-604: The influence of gravity and spread out. By 1850 million years ago this collapse had evolved to a dynamic of extensional tectonics . In this extensional milieu short-lived sedimentary basins formed. The Svecobaltic orogeny developed when subduction bought the Fennoscandian Craton into an oblique collision with the Sarmatian Craton . The mentioned sedimentary basins were destroyed by basin inversion 1830 million years ago. This last event of basin inversion

1924-451: The inner zone 1840–1790 million years ago. In addition to those two zones Baltybaev identifies a narrow zone of conjugation with Archean complexes between the outer zone and the Archean craton to the north and east. Nironen and Mänttäri (2012) uses the terms Central Svecofennian terrane and Southern Svecofennian terrane for approximately the same areas Baltybaev calls outer and inner zone respectively. The Oskarshamn-Jönköping belt

1976-475: The local rock. The ascent of this magma, while previously thought to have occurred as large, slow-rising and buoyant bodies, is now largely attributed to fast-moving narrow conduits and self-propagating dykes. These faster moving models have overcome major thermal and mechanical problems embedded in older theories as well as the granite problem and near surface felsic volcanism. As the flow of rising magma then changes from vertical back to horizontal, emplacement

2028-443: The melts themselves. Where partial melting is associated with regional tectonics and differential stresses, the production of melt creates instabilities in pore spaces and eventually along grain-boundaries that localize strain into crustal-scale shear zones. These zones promote melt flow out of the anatectic system as a mechanism to accommodate strain which in turn promotes more partial melting. The feedback loop that develops between

2080-475: The modelling process. Considerations that may influence the structure of a model might be the modeler's preference for a reduced ontology , preferences regarding statistical models versus deterministic models , discrete versus continuous time, etc. In any case, users of a model need to understand the assumptions made that are pertinent to its validity for a given use. Building a model requires abstraction . Assumptions are used in modelling in order to specify

2132-406: The nature of their source rock. One of the more popular classification schemes for granites was first introduced by White and Chappell in 1974. This classification scheme categorizes granites based on whether they are the result of the melting of sedimentary rocks (S-type granites) or the melting of igneous rocks (I-type granites). This genetic difference is reflected in the geochemical signature of

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2184-456: The northeast and an inner zone in the southwest. The inner zone is characterized by I-type calc-alkaline granitoids . In contrast the outer zone contains more S-type granitoids. There are differences between the metamorphosed sediments found in the two zones while the outer zone contains metagreywackes the inner zone hosts metapelites . Rocks of the outer zone are estimated to have formed 1890–1860 million years ago and granitoids of

2236-536: The orogenic activity ceasing after the collision between the Fennoscandian Craton and the Sarmatian Craton . Prior to the onset of orogeny the Archean -aged craton of what is today northeastern Fennoscandia rifted creating an ocean basin , the "pre-Svecofennian Ocean", that then closed during the Svecofennian orogeny. The closure of this basin was indebted to subduction and resulted thus both in

2288-535: The place of large scale, unreasonable models involving fractional melting of the mantle into granitic batholiths and plutons . Evidence for this can be seen in the physical, mineralogical, and isotopic signatures of countless granites. Crustal anatexis is not restricted to a single tectonic setting, but rather is controlled by four primary parameters: temperature, pressure, volatile content, and rock type/composition. These parameters are highly variable and depend on depth, crustal thickness, and local variations of

2340-418: The result of a variety of processes, including erosion , tectonic denudation , and lithospheric thinning. The amount of water available in the system plays a major role in controlling the degree of melting at a given temperature. Low water availability will suppress melting. Furthermore, the degree of water saturation of a system will affect the composition of any melt generated. Water can be derived from

2392-444: The rock record, one can expect to see macroscopic melt-rich layers ( leucosomes ), and macroscopic residual solid layers ( melanosomes ). These layers will commonly be oriented parallel to the fabric of the host rock. As the amount of accumulated melt in the surrounding rock increases, melt will travel further from its source towards growing transverse structures such as the aforementioned embrittlement fractures. Eventually, this leads to

2444-528: The scientist, a model is also a way in which the human thought processes can be amplified. For instance, models that are rendered in software allow scientists to leverage computational power to simulate, visualize, manipulate and gain intuition about the entity, phenomenon, or process being represented. Such computer models are in silico . Other types of scientific models are in vivo (living models, such as laboratory rats ) and in vitro (in glassware, such as tissue culture ). Models are typically used when it

2496-451: The set to other elements, and form relationships between an element of the set and elements not a part of the relational regime. There are two types of system models: 1) discrete in which the variables change instantaneously at separate points in time and, 2) continuous where the state variables change continuously with respect to time. Modelling is the process of generating a model as a conceptual representation of some phenomenon. Typically

2548-473: The subject. Modelling is an essential and inseparable part of many scientific disciplines, each of which has its own ideas about specific types of modelling. The following was said by John von Neumann . ... the sciences do not try to explain, they hardly even try to interpret, they mainly make models. By a model is meant a mathematical construct which, with the addition of certain verbal interpretations, describes observed phenomena. The justification of such

2600-468: The universe. However, a fit to empirical data alone is not sufficient for a model to be accepted as valid. Factors important in evaluating a model include: People may attempt to quantify the evaluation of a model using a utility function . Visualization is any technique for creating images, diagrams, or animations to communicate a message. Visualization through visual imagery has been an effective way to communicate both abstract and concrete ideas since

2652-501: The world easier to understand , define , quantify , visualize , or simulate . It requires selecting and identifying relevant aspects of a situation in the real world and then developing a model to replicate a system with those features. Different types of models may be used for different purposes, such as conceptual models to better understand, operational models to operationalize , mathematical models to quantify, computational models to simulate, and graphical models to visualize

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2704-491: Was associated with a period of metamorphism in southern Finland that peaked about 1820 million years ago. Two models exist regarding the origin of the Nordic orogeny: one proposes it as an Andean-type orogeny with subduction but no accretion or continental collision and the other poses it might have resulted from the collision of the Fennoscandian Craton with the Amazonia continent . The Svecofennian orogen underwent

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