Unreferenced date January 2007 Country rock is a Geology geological term meaning the rock native to an area. It is similar and in many cases interchangeable with the terms basement geology basement and wall rock s. The term is used to denote the usual strata of a region in relation to the rock which is being discussed or observed. The following are areas in geology when the term country rock is used Intrusive settings when describing a intrusion pluton or dike geology dike one may describe the igneous rock as intruding the surrounding country rock , the rock into which the pluton has intruded. In describing the texture or structure of lit par lit intrusion, the intrusive is described in relation to the country rock or wall rock Alluvial settings when describing recent alluvium the material that has arrived through volcano volcanic , glacier glacial or river fluvial action can be described as a veneer on the country rock Category igneous rocks Category Petrology Petrology stub ja ... more details
structures. Explanations A fold geology folded rock strata cut by a thrust fault B large intrusion ... deposited D dike geology volcanic dyke cutting through A, B & C E even younger rock strata overlying ..., metamorphic, and igneous rock Main RockgeologyRock cycle There are three major types of rock igneous, sedimentary, and metamorphic. The rock cycle is an important concept in geology which illustrates ... , and then deposition geology redeposited and lithification lithified into a sedimentary rock ... and give it a characteristic fabric geology fabric . The sedimentary rock can then be subsequently ... may once again crystallize. The majority of research in geology is associated with the study of rock ... are undergoing horizontal shortening. The geology of an area evolves through time as rock units ... are first emplaced either by deposition onto the surface or intrusion into the Country rockgeology ... geology dike s, and sill geology sills , push upwards into the overlying rock, and crystallize .... When rock units are placed under horizontal compression geology compression , they shorten and become ... the study of sedimentary layers , and structural geology the study of positions of rock units ... day positions of the rock units. Engineering geology Main Engineering geology Soil mechanics Geotechnical ...For the scientific journal Geology journal File WasatchFault.JPG thumb 300px Students examining the Wasatch Fault near Salt Lake City , Utah . Geology from the Ancient Greek Greek , g , earth and ... and changed. Geology provides primary evidence for plate tectonics , the history of life and evolution , and paleoclimatology past climates . In modern times, geology is commercially important for mining mineral and petroleum geology hydrocarbon exploration, evaluating water resources , is publicly ... Geology environmental problems, and understanding past climate change , plays an essential role in geotechnical engineering , and is a major academic discipline . History Main History of geology ... more details
Unreferenced stub auto yes date December 2009 In geology a lens is a body of ore or Rockgeologyrock or a deposit that is thick in the middle and thin at the edges, resembling a convex lens in cross section. Adjective lenticular . A lens can also refer to an irregular shaped formation consisting of a porous , Permeability fluid permeable sedimentary deposit surrounded by impermeable rock. DEFAULTSORT Lens Geology Category Petrology Category Sedimentology it Lente geologia uk Geology stub ... more details
Unreferenced stub auto yes date December 2009 A succession , in geology, is a group of rock units or stratum strata that succeed one another in chronology chronological order. Rock successions are often easily seen on exposed sections of a geology geological column or wall. Based on uncomfortable or comfortable succession. DEFAULTSORT Succession Geology Category Geochronology Geology stub ... more details
Unreferenced date December 2007 In geology the term compression refers to a set of stresses directed toward the center of a rock mass. Compressive strength refers to the maximum compressive stress that can be applied to a material before failure occurs. When the maximum compressive stress is in a horizontal orientation, thrust fault ing can occur, resulting in the shortening and thickening of that portion of the crust geology crust . When the maximum compressive stress is vertical, a section of rock will often fail in normal fault s, horizontally extending and vertically thinning a given layer of rock. Compressive stresses can also result in fold geology folding of rocks. Because of the large magnitudes of lithostatic stress in tectonic plate s, tectonic scale deformation geology deformation is always subjected to net compressive stress. See also Gravitational compression Category Geology Category Geology terminology geology stub ca Compressi mec nica ... more details
The geology of Norway encompasses the history of earth that can be interpreted by rock types found in Norway , and the associated sedimentological history of soils and rock types. The Norwegian mountains were formed around 400 million years ago during the Caledonian orogeny . References Landet blir til Norges geologi . 2007 Ramberg, I.B., Bryhni, I, & Nottvedt, A. red. Trondheim, Norsk Geologisk Forening. ISBN 82 92394 31 1 External links http www.ngu.no kart bg250 Interactive geological map of Norway See also Scandinavian mountains Geology of Europe DEFAULTSORT Geology Of Norway Category Geology of Norway regional geology stub no Norges geologi ... more details
of geology encompasses the composition, structure, physical properties, and history of Earth s components, and the processes by which they are shaped. Geologists typically study rockgeologyrock , sediment ... of rock types List of tectonic plates List of volcanoes See also portal Geology Outline of geography ...see also Index of geology articles Geology , one of the Earth science s, is the study of the Earth, with the general ... guide to geology Branches of geologyGeology applies primarily to Earth, but can be applied to any planet. Geology of Earth Subdisciplines of geology Economic geology Mining Mining geology Petroleum geology Engineering geology Environmental geology Geochemistry Geological modelling Geomorphology Geophysics Historical geology Hydrogeology Mineralogy Paleontology Petrology Sedimentology Stratigraphy Structural geology Volcanology Planetary geology Main Planetary geology See also Geology of solar terrestrial planets Geology of Mercury Geology of Venus Geology of the Moon Geology of Mars Jupiter Internal structure Geology of Jupiter Saturn Physical characteristics Geology of Saturn Uranus Physical characteristics Geology of Uranus Neptune Physical characteristics Geology of Neptune Main principles of geology Principle of intrusive relationships Principle of cross cutting relationships ... of faunal succession History of geology Main article History of geology Geological history of Earth Timeline of geology General geology concepts Geologic provinces Image World geologic provinces.jpg ... 89a 65 Ma Geologic province s legend f96 Shield geology Shield legend f9c Continental platform Platform legend 9fc Orogeny Orogen legend 9cf Basin geology Basin legend 969 Large igneous rock igneous province legend ff9 Extended crust geology crust border dc8 main Geologic province Geologic provinces based on origin Shield geology Shield Platform geology Platform shield covered with sediment Orogen ... province Extended Crust geology crust Rifted margin Rift Plate tectonics main Plate tectonics Occupations ... more details
Unreferenced date November 2009 A melanosome in geology refers to the dark, mafic mineral bands formed in migmatite which is undergoing eutaxitic melting probably to form granite . These form bands with leucosome s and such a texture may be described as schlieren or migmatitic . See also Metamorphism References http www.whitman.edu geology winter Petrology Ch 2022 20Metamorphic 20Classification.ppt metamorphic rock classification DEFAULTSORT Melanosome Geology Category Petrology geology stub ... more details
Unreferenced stub auto yes date December 2009 A sequence in geology refers to a sequence of geological events, processes, or rocks, arranged in chronology chronological order. A rock stratigraphy stratigraphical sequence is a geography geographical , or lithology lithostratigraphic , discrete unit greater than a group or supergroup rank, and traceable over large areas of a continent. A stratigraphic sequence is bounded by Unconformity unconformities of inter region al scope, such as in the division of craton s. DEFAULTSORT Sequence Geology Category Stratigraphy Category Geology terminology Geology stub ... more details
Fissility refers to the property of Rockgeologyrock s to split along planes of weakness into thin sheets. ref http books.google.co.uk books?id voakD8HV9DgC&pg PA92&lpg PA92&dq fissility&source bl&ots b818afMe2r&sig yFStYNTyUSEUSsfdqLBKwiEZNoE&hl en&ei bDm3Su cH9eN4gaGirV8&sa X&oi book result&ct result&resnum 10 v onepage&q fissility&f false Tucker , M.E. 2001. Sedimentary petrology an introduction to the origin of sedimentary rocks, WileyBlackwell, 3rd Edition, 272pp. ref This is commonly observed in shale s, which are sedimentary rock s, and in slate s and phyllite s, which are foliation geology foliated metamorphic rock s. The fissility in these rocks is caused by the preferred alignment of platy phyllosilicate grains due to Compaction geology compaction , deformation or new mineral growth. ref http bulletin.geoscienceworld.org cgi content abstract 64 8 869 Ingram, R.L. 1953. Fissility of mudrocks, GSA Bulletin, 64, 869 878. ref See also Cleavage geology Fabric geology Fissile Peak Flocculation References Reflist DEFAULTSORT Fissility Geology Category Structural geologygeology stub ... more details
Unreferenced date June 2009 In petroleum geology , the maturity of a Rockgeologyrock is a measure of its state in terms of hydrocarbon generation. Maturity is established using a combination of geochemistry geochemical and basin modelling techniques. Organic rich rocks termed source rock s will alter under increasing temperature such that the organic molecule s slowly mature into hydrocarbon s see diagenesis . Source rocks are therefore broadly categorised as immature no hydrocarbon generation , sub mature limited hydrocarbon generation , mature extensive hydrocarbon generation and overmature most hydrocarbons have been generated . The maturity of a source rock can also be used as an indicator of its hydrocarbon potential . That is, if a rock is sub mature, then it has a much higher potential to generate further hydrocarbons than one that is overmature. Category Petroleum geologygeology stub ... more details
Unreferenced date November 2006 The term cement in geology means the fine grained minerals which bind the coarser grained matrix in sedimentary rock s. Such cements are typically composed of calcite , quartz or clay minerals. See also Cementation geology Category Geology terminology Category Petrology Petrology stub de Zement Geologie et Tsement geoloogia pl spoiwo geologia ... more details
Unreferenced date June 2008 In geology , drift is transported rock debris overlying the solid bedrock . The term is also sometimes refers to organic debris so transported. In the largest sense, it refers to the material left behind by retreating continental glacier s. The transport mechanisms can include, but are not limited to, glacial and fluvial e.g. by glaciers or rivers , and mass movement including landslides. In the UK the term drift is commonly used to describe any Deposition geology deposits of Quaternary age. The Driftless Area refers to an unglaciated portion of North America devoid of the glacial drift of surrounding regions. Category Geology Category Driftless Area Geology stub no L smasseavsetning ... more details
Greenland is the largest island on Earth . Only one fifth of its surface area is exposed bedrock , the rest being covered by ice . The exposed surface is approximately 410,000 km sup 2 sup . Its geology is dominated by crystalline Rock geology rocks of the Precambrian Shield . ref name geus http www.geus.dk program areas raw materials greenl map greenland gr map anhstart uk.htm Greenland Geology. Geological Survey of Denmark and Greenland . 20 June 2003 retrieved 26 Dec 2010 ref There are large deposits of Rare earth element rare earth oxides at Kvanefjeld . See also Gemstone industry in Greenland Notes reflist Category Geology of Greenland Greenland stub regional geology stub no Gr nlands geologi ... more details
File Tibetan rocky land.JPG thumb 300px Tibet an rocky land, likely a result of combined eduction and erosion . In geology, eduction is a process in which the Earth crust spreads sideways, exposing deep seated rocks. It is prominent in middle layers of the Himalayas , where gravity pushes the mountains down. Together with a high grade of erosion, this activity brings deep rocks to the surface, many from more than a depth of 100 km. The unusually fast elevation preserves rare metastable minerals , e.g. diamonds and coesite . ref http geology.about.com od structureslandforms a tibetanplat.htm The Tibetan Plateau By Andrew Alden, About.com. Retrieved on April 12, 2009 ref See also Desert pavement , describing other forms of surface rock formation. References reflist DEFAULTSORT Eduction Geology Category Geology Category Geology terminology geology stub ... more details
References Reflist See also Rock microstructure Texture geology Orientation tensor DEFAULTSORT Fabric Geology Category Geology de Gef ge Geologie it Fabric geologia nl Maaksel ... of Structural Geology url http books.google.co.uk books?id ycASqdxSG3YC&pg PA52&dq 22shape fabric ... processes. S fabric a planar fabric such as Cleavage geology cleavage or Foliation geology foliation when it forms the dominant fabric in a rock, it may be called an S tectonite . L fabric a linear fabric such as mineral stretching Lineation geology lineation where aggregates of recrystallised grains ... it forms the dominant fabric in a rock, it may be called an L tectonite. Penetrative fabric a fabric that is present throughout the rock, generally down to the Particle size grain size grain scale ... more details
the hard competency geology competent crystalline rock crystalline rocks of these external massivs form ...dablink This article is about the geology of the European Alps . For the main article see geology of the Alps Geology of the Alps The Helvetic zone , Helvetic system or the Helveticum is a geology geologic subdivision of the Alps. The Helvetic zone outcrop crops out mainly in Switzerland , hence the name derived from Helveticus Latin for Swiss . Rocks in the Helvetic zone are sedimentary rock sedimentary and were originally sedimentation deposited at the southern continental margin margin of the Europe European plate . The Helvetic zone correlation correlates with the France French Dauphinois zone , French geologists often prefer the French name but normally this is considered the same thing. Occurrence In Switzerland the Helvetic zone is found in outcrops on the northern side of the Alpine mountain ranges. The French Alps consist mainly of Helvetic Dauphinois material. In Germany and Austria the Helvetic nappes crop out as a narrow band. Subdivision The Helvetic zone consists of a number of tectonics tectonically very different units. The Helvetic nappes are a nappe stack that was thrusted over the molasse of the Molasse basin in the Alpine foreland . They are composed of Mesozoic Marine ocean marine limestone , marl s and shale s. The Helvetic nappes are completely Decollement detached from their former basement geology basement . The Helvetic nappes are thrusted over the Infrahelvetic ... autochthonous Mesozoic sediments on top of Hercynian orogeny Hercynian basement rock. The Mesozoic ... deformation geology deformed by thrusting and fold ing that continues into the Hercynian basement ..., places where the Hercynian basement rock crops out in large anticlinorium anticlinoria at the southern ... alps schmid html Text Schmid.html Geology of the western and central Alps, website of S.M. Schmid Category Geology of the Alps Category Structural geology Category Geology of Switzerland de Helvetisches ... more details
In geology , the terms basement and crystalline basement are used to define the rocks below a sedimentation sedimentary platform geology platform or cover, or more generally any rock below sedimentary rock s or sedimentary basin s that are metamorphic rock metamorphic or Igneous rock igneous in origin. In the same way the sediment s and or sedimentary rocks on top of the basement can be called a cover or sedimentary cover . Usage In a discussion of Europe an geology, the basement generally refers to rocks older than the Variscan orogeny . Citation needed date September 2009 On top of this older basement Permian evaporite s and Mesozoic limestone s were deposited. The evaporites form a Strength of materials weak zone on which the harder stronger limestone cover was able to move over the hard basement, making the distinction between basement and cover even more pronounced. Citation needed date September 2009 In Andes Andean geology the basement refers to the Proterozoic , Paleozoic and early Mesozoic Triassic to Jurassic rock units as the basement to the late Mesozoic and Cenozoic Andean sequences developed following the onset of subduction along the western margin of the South American Plate . ref Teresa Moreno, et. al., The geology of Chile, Geological Society of London, 2007, Ch. 2 Metamorphic and Igneous Basement Complexes, p. 5, ISBN 978 1862392205 ref When discussing the Trans Mexican Volcanic Belt of Mexico the basement include Proterozoic, Paleozoic and Mesozoic age rocks ... A. Alaniz lvarez and Angel F. Nieto Samaniego, eds., Geology of M xico, Geological Society of America ... in disciplines of geology like Sedimentary basin basin geology , sedimentology and petroleum geology ... See also Craton platform geology Platform Shield geology Shield References Reflist Parker, Sybil P. Ed. . 1997. McGraw Hill Dictionary of Geology and Mineralogy. New York McGraw Hill. Bates, Robert L ... Basement Geology Category Cratons Category Plate tectonics Category Stratigraphy Category Geology ... more details
of other planar Fabric geology fabrics within a rock mass. In the case of the illustrated ...Unreferenced date December 2009 Lineations in structural geology are linear structural features within rocks. There are several types of lineations, intersection lineations, crenulation lineations, mineral lineations and stretching lineations being the most common. Lineations are measured as lines with a plunge and a plunge azimuth. Intersection lineations Image Stretch Conglomerate.jpg right 200px thumb Stretched pebble conglomerate L tectonite illustrating a stretch lineation within a shear zone , Glengarry Basin, Australia. Pronounced asymmetric shearing has stretched the conglomerate pebbles into elongate cigar shaped rods. Intersection lineations are linear structures formed by the intersection of any two surfaces in a three dimensional space. The trace of bedding on an intersecting foliation plane commonly appears as colour stripes generally parallel to local fold geology fold s hinges ... to the Structural geology Measurement conventions measurement conventions of structural geology , original bedding, S sub 0 sub intersected by a fold geology fold s axial plane foliation, forms ... Cleavage geology cleavage bedding intersection angle and is diagnostic of the plunge of the fold ... regimes. Stretching lineations are formed by Shear geology shearing of rocks during asymmetric deformation of a rock mass. Stretching lineations record primarily the vector of greatest stretch, which ... or shearing force is stretching the rock. Shortening occurs at the same time perpendicular to this stretched ... pebbles most likely were deposited as sub spherical pebbles and boulders. During deformation the rock ... be used to infer orientation information for folds or original bedding. See also Shear geology Foliation geologyRock microstructure Fold geology Tectonite DEFAULTSORT Lineation Geology Category Structural geology de Linear Geologie ... more details
unreferenced date July 2010 Unreferenced stub auto yes date December 2009 Otheruses Detritus Detritus IPA en d tra t s , adjective detrital , IPA en d tra t l pron is a geological term used to describe particles of Rock geology rock derived from pre existing rock through processes of weathering and erosion . Detrital particles can consist of Lithic Fragment geology lithic fragments particles of recognisable rock , or of monomineralic fragments mineral grains . These particles are often transported through sedimentary processes into depositional systems such as riverbeds, lakes or the ocean forming sedimentary successions. diagenesis Diagenetic processes can transform these sediments into rock through cementation and lithification , forming sedimentary rocks such as sandstone. These rocks can then in turn again be weathered and eroded to form a second generation of sediment. DEFAULTSORT Detritus Geology Petrology stub Category Sedimentology de Detritus Geologie eo Gruzo geologio he nl Detritus geologie ja ... more details
The geology of Oman includes varied landscapes which are a blend of its geological history, and its climate over the past few million years. Rock outcrops in the Al Hajar Mountains, the Huqf and Dhofar are a point of interest for international geologists. The rock record spans about 825 million years and includes at least three periods when the country was covered by ice. Oman , located at the southeast corner of the Arabian plate , is being pushed slowly northward, as the Red Sea grows wider. The lofty Al Hajar Mountains and the drowned valleys of Musandam are dramatic reminders of this. Generally speaking Oman is fairly quiescent tectonically. Musandan experiences occasional tremors as the Arabian Plate collides with the Eurasian Plate . During the Cretaceous Period Oman was located adjacent to a subduction zone and a portion of the upper Mantle geology mantle along with overlying seafloor volcanic rock s were Thrust fault thrust over the continental crust . This obduction obducted sequence of ultramafic to mafic rocks is the Semail ophiolite complex. The ophiolite is locally rich in copper and chromite Ore orebodies . ref Guilbert, John M. and Charles F. Park, Jr., 1984, The Geology of Ore Deposits , Freeman, p. 380 382 ISBN 0 7167 1456 6 ref ref Dilek, Yildirim et.al, eds. 2001, Ophiolites and Oceanic Crust , Geological Society of America, p. 57, ISBN 0 8137 2349 3 ref The interior plains of Oman are of young sedimentary rock s, wadi gravels, dune sands and salt flat s. Beneath them is a several kilometre thick stack of older sedimentary rocks that host the country s hydrocarbon resources. Ancient salt, which comes to the surface in several salt dome s such as Qarat Kibrit , plays an important role in forming many of these oil and gas accumulations. References reflist ... montp2.fr omanophiolite pages1 sommaire.htm Asia topic Geology of Category Geology of Oman Category Geography of Oman regional geology stub ... more details
Unreferenced stub auto yes date December 2009 image thrust system en.jpg thumb right 350px Schematic overview of a thrust system. The hanging wall block is when it has reasonable proportions called a nappe . If an erosion al hole is created in the nappe that is called a window. A klippe is a solitary outcrop of the nappe in the middle of autochthonous material. A tectonics tectonic window or Fenster lit. window in German language German is a geology geologic structure formed by erosion or normal fault ing on a thrust fault thrust system. In such a system the rock mass fault geology hanging wall block that has been transported by movement along the thrust is called a nappe . When erosion or normal faulting produces a hole in the nappe where the underlying autochthonous ie un transported rocks outcrop crop out this is called a window. Windows can be almost any size, from a couple of meter s to hundreds of kilometer s. DEFAULTSORT Window Geology Category Structural geology Category German words and phrases Geology stub de Fenster Geologie es Ventana tect nica fr Fen tre g ologie it Finestra tettonica nl Venster geologie nds Finster Geologie pl okno tektoniczne ... more details
link title Roadside geology of Idaho place Missoula, MT publisher Montana Press Publishing year ... Central Idaho Image Basalt idaho 1.jpg thumb right 200px center Basalt rock face at White Bird, Idaho ... See also Geology of the Pacific Northwest References Reflist United States topic title Geology of the United States by political division prefix Geology of Category Geology of Idaho ... more details
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