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     1 MEGA SETTING    
       sedimentary   Ingersoll and Busby (1995) from Visher 
           backarc basins   Oceanic basins behind intraoceanic magmatic arcs (inc interarc basins between active and remnant arcs) and cont. basins behind cont. margin magmatic arcs without foreland foldthrust belts 
           fore-arc basins   Basins within arc-trench gaps. 
           foreland intermontane basins   (Brokens forelands) Basins formed among basement-cored uplifts in foreland settings. 
           intra-arc basins   Basins along arc platform, which includes superposed and overlapping volcanoes. 
           peripheral foreland basins   Foreland basins above rifted continental margins that have been pulled into subduction zones during crustal collisions (primary type of collision-related forelands). 
           piggyback basins   Basins formed and carried atop moving thrust sheets 
           remnant ocean basins   Shrinking ocean basins caught between colliding continental margins and/or arc-trench systems, and ultimately subducted or deformed within suture belts. 
           retroarc foreland basins   Foreland basins on continental sides of continental-margin arc-trench systems (formed by subduction-generated compression and/or collision). 
           trench-slope basins   Local structural depressions developed on subduction complexes 
           trenches   Deep troughs formed by subduction of oceanic lithosphere 
           proto-oceanic rift troughs   Incipient oceanic basins floored by new oceanic crust and flanked by young rifted continental margins 
           terrestrial rift valley   Rifts within continental crust, commonly associated with bimodal volcanism. 
           aulacogens   Former failed rifts at high angles to continental margins, wihch ahve been reactivated during convergent tectonics so that they are at high angles to orogenic belts 
           impactogens   Rifts formed at high angles to orogenic belts, without pre-orogenic history 
           intracontinental wrench basins   Diverse basins formed within and on continental crust due to distant collisional processes 
           successor basins   Basins formed in intermontane settings following cessation of local orogenic or taphrogenic activity 
           active ocean basins   Basins floored by oceanic crust formed at divergent plate boundaries unrelated to arc-trench systems (spreading still active) 
           continental embankments   Progradational sediment wedges constructed off edges of rifted continental margins 
           continental platforms   Stable cratons covered with thin and laterally extensive sedimentary strata 
           continental rises and terraces   Mature rifted continental margins in intraplate settings at continental-oceanic interfaces 
           dormant ocean basins   Basins floored by oceanic crust, which is neither spreading nor subducting (no acitive plate boundaries within or adjoining basin) 
           intracratonic basins   Broad cratonic basins floored by fossil rifts in axial zones 
           oceanic islands, aseismic ridges and plateaux   Sedimentary aprons and platforms formed in intraoceanic settings other than magmatic arcs 
         transform and transcurrent-fault-related    
           transpressional basins   Basins formed by compression along strike-slip systems 
           transrotational basins   Basins formed by rotation of crustal blocks about vertical axes within strike-slip fault systems 
           transtensional basins   Basins formed by extension along strike-slip fault systems 
       tectonic  Definitions paraphrased from Condie: Plate Tectonics and Crustal Evolution (4th Edition)
         anorogenic granite   Subalkalic to peraluminous A-type granite emplaced in an anorogenic tectonic environment, enriched in REE, Zr and Hf, depleted in Sr, P and Ti with incompatable element and oxygen isotope distribution of lower crustal type  Condie 
         arc systems   Volcanic island chains developed on oceanic crust or continental margin volcanic chains developed on continental or transitional crust above active subduction zones idealy  consisting of an arc-trench gap, the arc and the arc-rear area (Condie) 
           accretionary prism   Steeply inclined melanges of sediment and volcanics including slab derived ophiolites as fault-bounded wedges accreted to the arc front above a descending oceanic slab (Condie) 
           arc   Subaerial and submarine volcanic chains erupting tholeiitic and calc-alkaline magmas above a descending oceanic slab (Condie) 
           back-arc basin   Behind arc over descending oceanic slabs, if active have high heat flow and thin often ophiolitic lithosphere and an ocean ridge enlarging the basin dominant sediments proximal (Condie) 
           forearc basin   Marine turbitite depositional basins up to 700km long overlying and arc-wards of the accretionary prism and lacking volcanism (Condie) 
           remnant arc   Extinct arc portions forming submarine aseismic ridges rifted away by opening of back-arc basins (Condie) 
           retroarc foreland basin   Continental margin arc-rear basin filled with syntectonic clastic terrigenious sediments from the fold thrust belt which becomes involved with the proximal margin + gives inversestratigraphic sampling as unroofing progresses (Condie) 
           trench   Very deep, narrow, extensive, linear, sediment poor structure formed in the ocean floor parallel to arc systems above where a lithospheric slab begins to decend into the mantle and subject to intense seismic activity (Condie) 
         archaean greenstone   Volcanic mainly subaqueous basalt + komatiite-dominated successions formed in arcs, submarine plateaux, volcanic islands + oceanic crust, mainly juvenile oceanic terranes. Post Archean gstns hve less komatiite+more volcaniclastics+adesitic+felsitic vlcncs 
         continental rifts   Simple to complex fault-bounded valleys to 70km wide and 1000s kms long in thin crust under tension with high, low order seismisity and immature terrigenous clastic sediments and bimodal volcanics, active rifts have more volcanics (Condie) 
         cratons and passive margins   Condie 
           craton   Precambrian tectonically stable elevated part of a continent composed of rocks that have been Precambrian tectonically stable elevated part of a continent composed of rocks that have been forming part of a shield (Condie) 
           passive margin   The continental edge of a rift that has developed into an ocean basin with rift assemblages underlying true margin assemblages of mature clastic sediments, where back arc basins also develop arc sediments may interfinger (Condie) 
         mantle plume related   Items that appear to be mainly due to the rise of mantle plumes to the base of the crust such as continental flood basalts and volcanic islands (Condie) 
           continental flood basalt   Extensive, thick, rapidly erupted low Mg + Fe dominantly tholeiitic basalt successions formed by entrainment + adiabatic melting of lower mantle material + some conductive* the lithosphere by a plume with a >1000 km diameter head (Condie) 
           giant mafic dyke swarms   Zones to 500km wide and 3000km long containing thousands of tholeiitic dykes to 200m thickand to 1000km long which are intruded laterally and widen sufacewards. Some radiate from a point (Condie) 
           submarine plateaux and aseismic ridges   Condie 
             aseismic ridges   Elongate steep-sided submarine volcanic ridges that mark the track of a mantle plume across the oceanic lithosphere during plate motion (Condie) 
             submarine plateaux   Large flat areas elevated some 2km above the seafloor comprised of thick rapidly erupted low Mg and Fe dominantly tholeiitic basalt and mafic intrusives covered with a thin layer of deep sea sediments (Condie) 
           volcanic island   Large volcanoes, developed over mantle plumes of dominantly tholeiitic lava erupted from the the sea floor and called seamounts before becoming subaerial when some alkali basalts are erupted (Condie) 
         ocean ridge   Wide spread linear rift systems forming accretionary plate boundaries where oceanic lithosphere is produced by extrusion of basaltic magma at the ridge during opening of an ocean basin following supercontinent breakup (Condie) 
         ophiolite   Tectonically emplaced layered oceanic crust fragment; ideal sequence from the base is ultramafic tectonite, commonly harzburgite; cumulate gabbros+ ultramafics; non-cumulate gabbros diorites + plagiogranites; sheeted diabase dykes; pillow basalts (Condie) 
         orogens   Events arising from the collision of two or more continents or a continent and an arc (Condie) 
           accretionary orogen   Collision and suturing of largely juvenile crustal blocks such as ophiolites, island arcs and submarine plateaux with little reworked older crust (Condie) 
           collisional orogen   Collision of two or more continental units commonly greatly thickening and partially melting the crust with extensive thrusting, folding, metamorphism and mountain formation (Condie) 
             foreland-hinterland deformational zone   Regions away from the main overthrust belts in the direction of and away from the direction of principle orogenic vergence respectively (Condie) 
             foreland flexure   Upwarped lithosphere area ahead of by major overthrust belts (Condie) 
             orogenic collapse   Local basin formed in foreland area when subduction stops or reverses (Condie) 
             plateau   Area elevated 1 to 5km adjacent to the suture zone in the near hinterland of fold thrust belts (Condie) 
             suture   A ductile shear zone along converging plate boundaries containing rocks from both plates, often in a serpentine-rich matrix (Condie) 
             thrust belt   Area of main thrusting and folding in suture foreland of collision orogen (Condie) 
         plain ocean floor   effectively "non-tectonic", in same sense as craton; added by CPS to Condie classes 
       depth   Selected by CPS 
           deep crust    
           middle crust    
           shallow crust    
           upper mantle    
       igneous   Geological Society of London Handbook 
           lava plateau    
           shield volcano    
             central   within 2km of central vent 
             distal   greater than 15km from central vent 
             proximal   2 to 15 km from central vent 
           batholiths   50-150km width, 500 - 1500km length 
             cone sheets    
             ring dykes    
           pluton   5 - 50km in breadth, with circular outcrop 
           stock   circular, surface area less than 100km sq 
       metamorphic   Geological Society of London Handbook 
         glaucophane eclogite    
         high grade    
         jadeite blueschist    
         low grade    
         marginal blueschist    
         medium grade    
         very low grade    
           eolian   Wind-driven depositional setting giving rise to ripple/dune/interdune/sheet sand bedforms.  Bedforms rarely preserved in ancient eolian deposits 
             eolian dry system-   The water table and its capillary fringe lie at depth below the depositional surface 
             eolian stabilized system-   Vegetation, surface cementation or mud drapes play a significant stabilising role and thus influence the behaviour of the accummulating surface 
             eolian wet system-   The water table or its capillary fringe is at or near the depositional surface 
           fluvial   River/stream/alluvial fan depositional setting 
             alluvial fan   Cone-shaped to arcuate deposits (in plan view)  w. a well dvpled network of distributory channels that cross the fan.  Many have steep depositional slopes 
               alluival fan braided-   Inner fan: longitudinal gravel bars; Mid-fan: longitudinal gravel bars and transverse bars; Outer fan: transverse bars and dunes 
               alluvial fan debris flow-dominated-   Inner fan: channelized proximal debris flows; Mid-fan: distal debris flows and sheet flows; Outer Fan: sheet flows and shallow braided stream 
               alluvial fan low-sinuousity/meandering-   Inner fan: active meander belts; Mid-fan: low-sinuousity/anastomosing river w vegetated levees; Outer fan: low sinuousity/ansotmosing river w little channel confinement 
             river systems    
               braided stream   Low sinuousity, high gradient streams charactersied by the presence of many channels separated by bars or small islands.  Occur in areas of high relief and have ltd. areal extent. 
               meandering stream   Highly sinuous, low gradient streams with finer sed. load.  Tend to be confined within a single major channel, char. by cohesive banks that are difficult to erode 
                 channel   Lag deposits composed of coarse material the river can move only at max. stream velocity during flood stage.  Bedding indistinct but imbrication common 
                 crevasse-splay deposits   Occur on floodplains where rising floodwaters breach natural levees 
                 floodbasin (floodplain) deposits   Fine-grained sediments that settle out of suspension from floodwaters carried into the floodbasin.  Broad, low-relief plain/swamp 
                 natural-levee deposits   Form on the concave or steep-bank side of meander loops immediately adjacent to the channel due to sudden loss of stream competence as they overtop their banks 
                 oxbow-lake deposits   Fine silt and mud introduced into the lakes from the main stream during overbank flooding 
           glacial   Areas where more or less permanent accumulations of snow exist; composite depositional setting 
             glacier continental (ice sheet)   Huge sheets or ice that spread over large continental areas or plateaus 
             glacier piedmont   Large masses or sheets of ice formed at the base of a mountain 
             glacier valley   Relatively small ice masses  confined to within valley walls of a mountain 
           lacustrine   Lake depositional setting 
             closed lake   Lakes do not have a major outflow, have fluctuating shorelines and occur in regions of interior drainage ; inflow is commonly exceeded by evaporation and infiltration leading to chemical sedimentation 
               basin ephemeral salt-pan   Fed by ephemeral (intermittent) runoff, springs and groundwater and are generally dry through each part of the year; bedded salt deposits are dominant 
               basin perennial   Mostly saline lakes which receive inflow from at least one perennial stream and commonly do not dry up completely from year to year, 
             open lake   Lakes have an outflow of water and a relatively stable (fixed) shoreline and in which inflow=precipitation.  Siliciclastic sediment commonly predominates 
         marginal-marine   Narrow zone dominated by river, wave and tidal processes lying along the boundary between the continental and marine depositional realms 
           beach/barrier island   Long, narrow accumulations of sand aligned parallel to the shoreline and attached to land.  High energy environment 
           coastal lagoon   Shallow stretch of seawater (sound, channel, bay) partly/completely separated from the sea by a low, narrow strip of land commonly extending parallel to the coast. No significant fresh water runoff. 
           deltaic   Discrete shoreline protuberances formed where rivers enter oceans, semi-enclosed seas, lakes or lagoons and supply sediment more rapidly than it can be redistributed by basinal processes 
             delta alluvial-fan-   Formed where alluvial fans prograde into standing water 
             delta braidplain-   Formed from the deposits of a braided stream system 
             delta river-   Formed from the deposits of a single river 
             delta scree-apron-   Formed where scree deposits extend into water 
           estuarine   Lower courses of rivers open to the sea which receive sediment from both fluvial and marine sources 
             estuary tide-dominated-   Occur mainly on macrotidal coasts where tidal-current energy exceeds wave energy at the mouth of the estuary 
             estuary wave-dominated-   Tidal influence is small, and the mouth of the estuary experiences high wave energy, seds. move alongshore and onshore in the mouth of estuary 
           glacial-marine   Sediments deposited where glaciers extend beyond the mouths of river valleys to enter the sea 
           sabkha   Coastal supratidal mudflats. Algal mats (stromatolites) commonly form in associated intertidal to supratidal sediments 
             salina   Marine-fed coastal lagoons and salt pans which occur in depressions on sabkhas, between coastal dunes, on deltas, or in tectonic downwarps behind coastal barriers 
           tidal flat   Marshy and muddy to sandy featureless plains dissected by a network of tidal channels and creeks that are largely exposed during low tide 
           basin-central evaporites   Evaporites accumulated from shallow bodies of brine or within saline mudfalts 
           continental shelf   Encompasses the shallow-water areas of the ocean lying shoreward of the shelf break 
             basin-margin evaporite shelf   Evaporites formed in vast expanses of evaporitic lagoons and mudflats,over which brine depths are only a few metres 
             carbonate shelf   Shelf char. by topographic buildup at the shelf margin of the outer shelf creating a barrier to incoming waves 
               carbonates outer shelf-   High energy tidal environ. with lag deposits composed of skeletal fragments of shallow-water organisms such as corals, calcareous algae, and bryozoa and/or ooids and peloids 
               carbonates peritidal   Low energy, tidal flat environ. in which predominantly fine-grnd seds. accumulate.  Generally consist of  pelleted mudstones Syn; inner tidal 
               epiric platform   Shallow (often broad) seas occupying areas within continents, associated with widespread deposition of carbonate sediments 
               isolated carbonte platform   Deposits formed within interiors of isolated carbonate platforms under moderately low-energy, open to restricted subtidal conditions 
               organic reefs   Biological buildup of carbonate sediment which affects deposition in adjacent areas and stands topographically higher than surrounding sediments during deposition 
                 barrier reef   Linear reefs located along platform margins; reefs are more or less laterally continuous and may extend for hundreds of kms 
                 fringing reef   Narrow, linear reef located hard up against the shoreline, with no intervening lagoon 
               ramp (progressive)   Sed. succession; outer-ramp carbonate muds give way in shoreward direction to bioclastic sand bodies give way to ooid sand bodies in near shore area 
           deep ocean floor   Encompasses abysall plain/lower continental slope/lower reaches of submarine canyons 
             pelagic rain   Fine grained sediment deposited far from land  influence by slow settling of particles suspended in the water column 
             turbidity currents   Catastrophic or surge-type, high-velocity turbidity currents generated on the shelf or upper slope transporting sands and gravels to deeper water through submarine channels 
               canyon axis   Submarine canyons discharge turbidites into fore-arc basins on the slope or into deep-sea trenches where they may spread out along the canyon axis 
               submarine fan   Deposits of flows spread out from the mouths of canyons onto the deep seafloor to form deep-sea fans.  Typical of passive margin and back-arc basin setting 
       structural   Hobbs, Means and Williams (1976) 
         areas of gently dipping schistosity   Regions in which prominent schistosity has a gentle dip over 1000s of sq km (eg: Otago Schist terrain, NZ) 
         block-faulted and rifted regions   Systems of approx parallel faults with dip-slip displacements of 100s or 1000s of metres (eg: Basin & Range Prov) 
         depressed   added by CPS (downthrown or downwarped) 
         dome and basin structure   Areas of doubly plunging anticlines and synclines (eg: Kettleman Hills, California) 
         elevated   added by CPS (uplifted or upwarped) 
         flat-lying sediments   Extensive deposits of flat-lying or gently tilted or warped seds (eg: Colorado Plateau) 
         gneissic regions   Upper amph and granulite facies rocks of similar geometry to mult def rocks of lower met grade, but with particular problems in understanding because of destroyed structure 
         horst and graben   added by CPS 
         jog zones   added by CPS 
         mantled gneiss domes   Core of granitic migmatites/gneisses overlain by a layered metasedimantary & metavolc cover (Eskola 1949: Caledonides of Finland) 
         multiply deformed belts of low and medium metamorphism   As present as parts of virtually all the world's fold-mountain belts. 
         mylonite zones   Narrow planar regions in which deformation is intense relative to the adjacent rocks 
         nappe structures   Allochthonous regions of large-scale thrusting with or without recumbant folding  of rocks of essentially horizontal undisturbed material. 
         salt domes   Regions of diapiric uprise of thick columnar plug-like bodies of halite (eg: Gulf Coast, USA) 
         shallow fold and thrust belts   Shallow-deformed rocks above a decollement zone, oft referred to as suprastructure of mtn belts (cf: infrastructure) eg: Canadian Rocky Mtns 
         simple fold systems with steeply dipping axial surfaces   Areas of regular trains of gently plunging folds of similar size orientation and steeply dipping axial surfaces (eg: Appalachain Fold Belt) 
         slate belts   Typically narrow zones of slate parallel to orogenic belts (exception: equidimensional slate belt in N Wales) 
         tectonic melanges   Environment of juxtaposition of large-scale exotic rock blocks on blocks & matrix of different age or lithology. (eg: Ankara melange: Turkey) 
         tripple junction   added by CPS 
         wrench-faulted regions   Major transcurrent faults in continental rocks, typically 100s of km long (eg: Alpine Fault in New Zealand) 

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Date Generated: 15/05/2002 6:45:56 PM.