Journal articles: 'West Spitsbergen Fold-and-Thrust Belt'

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SAALMANN, K., and F. THIEDIG. "Thrust tectonics on Brøggerhalvøya and their relationship to the Tertiary West Spitsbergen Fold-and-Thrust Belt." Geological Magazine 139, no. 1 (January 2002): 47–72. http://dx.doi.org/10.1017/s0016756801006069.

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The Tertiary fold-and-thrust belt on Brøggerhalvøya is characterized by a NE-vergent pile of nine thrust sheets. The sole thrust of the pile is located in Precambrian phyllites and climbs up-section to the northeast. Four lower thrust sheets consisting predominantly of Upper Palaeozoic sediments are overlain by two thrust sheets in the central part of the stack which contain a kilometre-scale syncline and anticline. The fold is cut by juxtaposed thrusts giving rise to the formation of three structurally higher basement-dominated thrust sheets. A multiple-stage kinematic model is proposed including (1) in-sequence foreland-propagating formation of the lower thrust sheets in response to N–S subhorizontal bedding-parallel movements, (2) a change in tectonic transport to ENE and out-of-sequence thrusting and formation of the kilometre-scale fold-structure followed by (3) truncation of the kilometre-scale fold and stacking of the highest basement-dominated thrust sheets by hind-ward-propagating out-of-sequence thrusting. The strain of the thrust sheets is predominantly compressive with the exception of the structurally highest thrust sheets, reflecting a temporal change to a more transpressive regime. Thrusting was followed by (4) N–S extension and (5) W–E extension. Comparison of the structural geometry and kinematic evolution of Brøggerhalvøya with the data reported for the fold belt further south allows us to assume a coeval evolution with the fold belt. A latest Paleocene/Early Eocene age for the main phase of thrusting is suggested for the West Spitsbergen Fold-and-Thrust Belt; the main phases therefore pre-date the separation of Svalbard and Greenland due to right-lateral movements along the Hornsund Fault Zone. The fold belt's temporal evolution followed by the formation of the Forlandsundet Graben can be linked with the plate-kinematic framework in the span between latest Paleocene and Middle Eocene times.

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Wennberg, Ole Petter, Arild Andresen, Sigurd Hansen, and Steffen G. Bergh. "Structural evolution of a frontal ramp section of the West Spitsbergen, Tertiary fold and thrust belt, north of Isfjorden, Spitsbergen." Geological Magazine 131, no. 1 (January 1994): 67–80. http://dx.doi.org/10.1017/s0016756800010505.

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AbstractThe geometry and kinematic evolution of a frontal ramp section associated with the Tertiary West Spitsbergen Orogenic Belt has been investigated in a small area (Lappdalen) north of Isfjorden. The previously recognized thrust front corresponds to a complex step or ramp in the position of the sole-thrust in the area. The sole-thrust is localized to the evaporites of the Permian Gipshuken Formation to the west of the footwall ramp, whereas to the east it continues as a bedding-parallel thrust in Triassic shales (Sassendalen Group). The area to the west of the footwall ramp is characterized by large scale thrusts and folds involving the Permian Gipshuken and Kapp Starostin formations and the lower part of the Triassic Sassendalen Group. East of the footwall ramp both Permian and Triassic strata are sub-horizontal and apparently undeformed. Three major thrust sheets are recognized. Based on the geometric relationship between folds and faults in the area, both fault-bend and fault-propogation mechanisms of folding are inferred. Restoration of the Kapp Starostin Formation to its pre-deformational state indicates a minimum of 35% shortening. Structural observations within the Sassendalen Group in the study area and on Dickson Land suggest that some of this shortening is transmitted eastwards along one or more bedding parallel thrusts in the Sassendalen Group.

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Saalmann, K., and F. Thiedig. "Tertiary West Spitsbergen fold and thrust belt on Brøggerhalvøya, Svalbard: Structural evolution and kinematics." Tectonics 20, no. 6 (December 2001): 976–98. http://dx.doi.org/10.1029/2001tc900016.

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Leever, Karen A., Roy H. Gabrielsen, Jan Inge Faleide, and Alvar Braathen. "A transpressional origin for the West Spitsbergen fold-and-thrust belt: Insight from analog modeling." Tectonics 30, no. 2 (April 2011): n/a. http://dx.doi.org/10.1029/2010tc002753.

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Harland, W. Brian. "Chapter 9 Central western Spitsbergen." Geological Society, London, Memoirs 17, no. 1 (1997): 154–78. http://dx.doi.org/10.1144/gsl.mem.1997.017.01.09.

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The West Spitsbergen Orogen extends along the western side of Spitsbergen from Kongsfjorden to Sørkapp. It is the product of the latest main deformation event in Svalbard (Spitsbergian) dated provisionally as Eocene. The deformation is of a compressive or transpressive nature associated with the dextral strike-slip displacement between Svalbard and Greenland through Cenozoic time.Within this fold and thrust belt earlier diastrophism is evident: Minor Late Cretaceous tilting with uplift took place. The main events were mid-Paleozoic. The mid-Paleozoic tectogenesis is commonly referred to as Caledonian. However the age of deformation appears to be mid-Ordovician rather than the typical mid-Silurian of the central and eastern terranes of Svalbard. To avoid confusion this is referred to as the Eidembreen tectogenesis (analogous with the M'Clintock Orogeny of northern Ellesmere Island). Some uncertainty must remain as to whether there was any Silurian diastrophism or more likely, late Devonian Early Carboniferous tectonism to match the Ellesmerian events of Arctic Canada. The rocks divide naturally into younger (Carboniferous through Eocene) strata, i.e. post-Devonian, and pre-Devonian older rocks, there being no Devonian exposure within the orogen.Whereas the West Spitsbergen Orogeny was Paleogene (treated in Chapter 20) the orogen comprises the whole body of rock whether formed earlier or later. Because of the complex earlier history and variety of strata and structure along its length it is convenient to treat the structure in two parts, north and south of Isfjorden (Chapters 9 and 10 respectively). In this chapter the area treated comprises Oscar II Land and

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Dudzisz, Katarzyna, Rafał Szaniawski, Krzysztof Michalski, and Martin Chadima. "Rock magnetism and magnetic fabric of the Triassic rocks from the West Spitsbergen Fold-and-Thrust Belt and its foreland." Tectonophysics 728-729 (March 2018): 104–18. http://dx.doi.org/10.1016/j.tecto.2018.02.007.

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Manby, G. M., and N. Lyberis. "State of stress and tectonic evolution of the West Spitsbergen Fold Belt." Tectonophysics 267, no. 1-4 (December 1996): 1–29. http://dx.doi.org/10.1016/s0040-1951(96)00109-6.

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Mann, A., and C. Townsend. "The post-Devonian tectonic evolution of southern Spitsbergen illustrated by structural cross-sections through Bellsund and Hornsund." Geological Magazine 126, no. 5 (September 1989): 549–66. http://dx.doi.org/10.1017/s0016756800022846.

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AbstractConstruction of cross-sections in Bellsund and Hornsund, southern Spitsbergen, using offshore and onshore structural data illustrate the main tectonic units of the region. From west to east these are: a wedge of late Cenozoic clastic sediments; a series of late Palaeozoic to early Mesozoic grabens controlled by basement faults along the west Spitsbergen margin; the Basement Horst, comprising late Precambrian to early Palaeozoic rocks deformed and metamorphosed during a mid-Palaeozoic orogeny; the Fold Belt, which forms a narrow NNW–SSE striking zone of eastward verging folds and thrusts attributed to Eocene inversion of a pre-Cenozoic basin; the Palaeogene Central Basin, deformed into a broad synclinorium and bound to the east by the Billefjorden Fault Zone. This basement lineament shows evidence of Palaeogene reactivation and may be linked to the Fold Belt by a detachment zone beneath the Central Basin. East of Spitsbergen, there is an offshore basin of possible Carboniferous age controlled by the Storfjorden Fault Zone which shows evidence of later inversion to form a positive flower structure.

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Dudzisz, Katarzyna, Rafał Szaniawski, Krzysztof Michalski, and Geoffrey Manby. "Applying the anisotropy of magnetic susceptibility technique to the study of the tectonic evolution of the West Spitsbergen Fold-and-Thrust Belt." Polar Research 35, no. 1 (January 2016): 31683. http://dx.doi.org/10.3402/polar.v35.31683.

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DUDZISZ, KATARZYNA, KRZYSZTOF MICHALSKI, RAFAŁ SZANIAWSKI, KRZYSZTOF NEJBERT, and GEOFFREY MANBY. "Palaeomagnetic, rock-magnetic and mineralogical investigations of the Lower Triassic Vardebukta Formation from the southern part of the West Spitsbergen Fold and Thrust Belt." Geological Magazine 156, no. 4 (January 31, 2018): 620–38. http://dx.doi.org/10.1017/s0016756817001145.

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AbstractMagnetic, petrological and mineralogical data from 13 sites (99 independently oriented samples) of the Lower Triassic rocks located in the SW segment of the West Spitsbergen Fold and Thrust Belt (WSFTB) are presented in order to identify the ferrimagnetic carriers and establish the origin of the natural remanent magnetization (NRM). Volcanic lithoclasts and other detrital resistive grains in which the primary magnetization might endure are present in some samples. On the other hand, petrological studies indicate that sulphide remineralization could have had an important influence on the remagnetization of these rocks. The dominant ferrimagnetic carriers are titanomagnetite and magnetite. While the titanomagnetite may preserve the primary magnetization, the magnetite is a more likely potential carrier of secondary overprints. The complex NRM patterns found in most of the samples may be explained by the coexistence and partial overlapping of components representing different stages of magnetization. Components of both polarities were identified in the investigated material. The reversal test performed on the most stable components that demagnetized above 300°C proved to be negative at the 95% confidence level at any stage of unfolding. They are better grouped, however, after 100% tectonic corrections and the most stable components are clustered in high inclinations (c. 70–80°). This suggests that at least part of the measured palaeomagnetic vectors represent a secondary prefolding magnetic overprint that originated in post-Jurassic time before the WSFTB event. Vitrinite reflectance studies show these rocks have not been subjected to any strong heating (<200°C).

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11

Harland, W. Brian, and Isobel Geddes. "Chapter 17 Carboniferous-Permian history of Svalbard." Geological Society, London, Memoirs 17, no. 1 (1997): 310–39. http://dx.doi.org/10.1144/gsl.mem.1997.017.01.17.

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Rocks formed in these two periods do not easily divide at their mutual boundary and it is convenient to treat them together. In doing so we are addressing perhaps the best known and most conspicuous formations of Svalbard. Few geologists have been to the archipelago without noticing fossils and making some observations on these rocks. We are therefore embarking on a substantial study. A three-fold division of Paleozoic rocks in Svalbard is convenient in which Silurian and Devonian or middle Paleozoic history, dominated by Caledonian events, is followed by a Late Paleozoic interval of increasingly stable conditions which show little impact from Variscan, Ellesmerian or Uralian events elsewhere. This contrast applies conspicuously in Permian western Arctic regions.The Carboniferous-Permian outcrops are shown on Fig. 17.1. These rocks are the lower element in the Post-Devonian cover sequence divided between the Spitsbergen Basin and the Eastern Platform and Bjørnøya.The outcrops are disposed in two main areas in Spitsbergen and one in Bjørnøya. The Spitsbergen Basin was at first divided into troughs by inherited N-S faults. These then coalesced and extended throughout Spitsbergen.The present outcrop pattern resulted (i) from Late Cretaceous tilting with loss by erosion to the north, burial to the south and wide E-W exposure across the middle.(ii) A linear belt along the west coast, brought to the surface by folding and uplift along the Cenozoic West Spitsbergen Orogenic Belt from Kongsfjorden to Hornsund. Outcrops are frequently controlled by overthrusting from the west.(iii) The Bjørnøya Carboniferous outcrop

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12

Blinova, Maria, Jan Inge Faleide, Roy H. Gabrielsen, and Rolf Mjelde. "Analysis of structural trends of sub-sea-floor strata in the Isfjorden area of the West Spitsbergen Fold-and-Thrust Belt based on multichannel seismic data." Journal of the Geological Society 170, no. 4 (May 24, 2013): 657–68. http://dx.doi.org/10.1144/jgs2012-109.

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13

Krysiński, Lech, Marek Grad, Rolf Mjelde, Wojciech Czuba, and Aleksander Guterch. "Seismic and density structure of the lithosphere−asthenosphere system along transect Knipovich Ridge−Spitsbergen−Barents Sea – geological and petrophysical implications." Polish Polar Research 34, no. 2 (June 1, 2013): 111–38. http://dx.doi.org/10.2478/popore-2013-0011.

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AbstractThis paper presents a study of the seismic P−wave velocity and density structure of the lithosphere−asthenosphere system along a 800 km long transect extending from the actively spreading Knipovich Ridge, across southern Spitsbergen to the Kong Karls Land Volcanic Province. The 2D seismic and density model documents 6-8 km thick oceanic crust formed at the Knipovich Ridge, a distinct continent−ocean−boundary (COB), the east− ern boundary of the dominantly sheared Hornsund Fault Zone, and the eastern boundary of the Early Cenozoic West Spitsbergen Fold−and−Thrust Belt. The crustal continent−ocean transitional zone has significant excess of density (more than 0.1 g/cm3in average), charac− teristic for mafic/ultramafic and high−grade metamorphic rocks. The main Caledonian su− ture zone between Laurentia and Barentsia is interpreted based on variations in crustal thickness, velocities and densities. A high velocity body in the lower crust is preferably in− terpreted in terms of Early Cretaceous magmatism channelled from an Arctic source south− wards along the proto−Hornsund zone of weakness. The continental upper mantle expresses high velocities (8.24 km/s) and densities (3.2 g/cm3), which may be interpreted in terms of low heat−flow and composition dominated by dunites. The lower velocities (7.85 km/s) and densities (3.1 g/cm3) observed in the oceanic lithosphere suggest composition dominated by primitive peridotites. The model of mantle allows for successful direct description of subcrustal masses distribution compensating isostatically uneven crustal load. The esti− mated low value of correlation between density and velocity in the mantle 0.12 kg·s·m−4suggests that horizontal density differences between oceanic and continental mantle would be dominated by compositional changes.

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Lyberis, Nicolas, and Geoff Manby. "The origin of the West Spitsbergen Fold Belt from geological constraints and plate kinematics: Implications for the Arctic." Tectonophysics 224, no. 4 (September 1993): 371–91. http://dx.doi.org/10.1016/0040-1951(93)90039-m.

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15

Jochmann, Malte Michel, Lars Eivind Augland, Olaf Lenz, Gerd Bieg, Turid Haugen, Sten Andreas Grundvåg, Mads E. Jelby, Ivar Midtkandal, Martina Dolezych, and Hanna Rósa Hjálmarsdóttir. "Sylfjellet: a new outcrop of the Paleogene Van Mijenfjorden Group in Svalbard." arktos 6, no. 1-3 (December 5, 2019): 17–38. http://dx.doi.org/10.1007/s41063-019-00072-w.

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AbstractA hitherto unrecognized Paleogene outcrop has been discovered at Sylfjellet, a mountain located at the northern side of Isfjorden, Svalbard. The strata, which cover an area of 0.8 km2, have until now been assigned to the Lower Cretaceous succession of the Adventdalen Group. In this study, the Sylfjellet site was studied in detail to provide an updated structural and sedimentological description of strata and lithostratigraphy. The age and burial history of the investigated succession were constrained by absolute (U/PB) and relative dating methods in addition to vitrinite reflectance analyses of coal seams. The results show a Paleogene age of the deposits, which is supported by the occurrence of an angiosperm pollen grain, plant macrofossils, and a tephra layer of early Selandian age (61.53 Ma). The 250 m-thick succession of Sylfjellet is assigned to the Firkanten, Basilika and Grumantbyen formations. This succession unconformably overlies the Lower Cretaceous Helvetiafjellet Formation. Sylfjellet is incorporated into the West Spitsbergen Fold-and-Thrust Belt and interpreted to be a fourth structural outlier of the Van Mijenfjorden Group. Vitrinite reflectance data indicate that at least 2000 m overburden has been eroded above the Sylfjellet coal seams, and that maximum burial of the strata predates folding and thrusting in the area.

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16

Lepvrier, C. "The origin of the West Spitsbergen Fold belt from geological constraints and plate kinematics: implications for the Arctic—Comment." Tectonophysics 234, no. 4 (July 1994): 329–33. http://dx.doi.org/10.1016/0040-1951(94)90231-3.

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17

Lyberis, Nikos, and Geoff Manby. "The origin of the West Spitsbergen Fold Belt from geological constraints and plate kinematics: implications for the Arctic—Reply." Tectonophysics 234, no. 4 (July 1994): 334–37. http://dx.doi.org/10.1016/0040-1951(94)90232-1.

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18

McCann, Andrew J., and Winfried K. Dallmann. "Reactivation history of the long-lived Billefjorden Fault Zone in north central Spitsbergen, Svalbard." Geological Magazine 133, no. 1 (January 1996): 63–84. http://dx.doi.org/10.1017/s0016756800007251.

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AbstractNew geological mapping has revealed further details of the tectonic and stratigraphic effects of Devonian and later reactivations of the Billefjorden Fault Zone, one of a number of important north—south trending lineaments in Svalbard. Analysis of offsets along the many steeply-dipping faults within the zone, and effects on the subsidence and deformation of the adjacent crustal blocks, is presented as a series of tectonic maps from the Late Devonian through to the Tertiary. Late Devonian sinistral transpression, suggested previously, cannot be ruled out, and Carboniferous reactivation was dominated by extension, with possibly a slight dextral strike-slip component. After Late Carboniferous to Early Cretaceous platform subsidence, during which the fault zone had little effect on sedimentation, development of the Tertiary West Spitsbergen Fold Belt (related to the opening of the Arctic Ocean) involved compressive (and transpressive?) reactivation of basement-seated structures further east, including the Billefjorden Fault Zone. In the Billefjorden—Austfjorden area this produced a large monoclinal fold across the fault zone, which was later cross-cut by extensional structures to produce the present day Billefjorden syncline. This localized late extension is related to a slight variation in the trend of the Billefjorden Fault Zone through this area.

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19

Harland, W. B., N. Lyberis, and G. Manby. "Discussion of ‘The West Spitsbergen Fold Belt: The result of Late Cretaceous-Palaeocene Greenland-Svalbard convergence?’ by N. Lyberis and G. M. Manby. Reply." Geological Journal 30, no. 2 (June 1995): 189–95. http://dx.doi.org/10.1002/gj.3350300209.

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20

Patterson, Judith G. "The Amer Belt: remnant of an Aphebian foreland fold and thrust belt." Canadian Journal of Earth Sciences 23, no. 12 (December 1, 1986): 2012–23. http://dx.doi.org/10.1139/e86-186.

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Aphebian supracrustal sequences occur as outliers throughout the northwestern portion of the Churchill Structural Province of the Canadian Shield. In the Amer Lake area, medium- to high-grade, polydeformed Archean rocks are unconformably overlain by the Amer supracrustal sequence, which comprises quartzite, carbonate, mafic volcanic, and meta-arkose and meta-pelitic units. This supracrustal sequence is interpreted as having been deposited under miogeoclinal conditions, transitional to exogeoclinal.The Amer sequence crops out in a broad, west-southwest-plunging synclinorium and contains evidence of polyphase deformation that includes the following: (1) Folds plunging gently to the west-southwest and west-southwest-striking thrust faults, transected by oblique tear faults. Thrust vergence is northerly to northwesterly, onto the Archean craton. Because of the orientation of the synclinorium, there is a down plunge view of the thrusts at the eastern end of the belt. (2) Younger, localized cross folds, probably representative of progressive deformation. (3) Late, northwest-trending normal faults, with east side down.The stratigraphic elements and family of structures in the Amer Belt are similar to those found in the foreland fold and thrust belts of major Phanerozoic and Proterozoic orogens. The Amer Belt is interpreted as being a remnant of a once extensive foreland fold and thrust belt.Some workers have considered the northwestern Churchill Structural Province a large cratonic foreland of the Trans-Hudson Orogen. However, remnants of a foreland fold and thrust belt, a major batholithic complex, and profound geophysical breaks interpreted as being possible sutures are incorporated into a new tectono-stratigraphic model that proposes that a cryptic Aphebian orogen exists in the northwestern Churchill Structural Province.

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21

Chapman, James B., and Reid S. McCarty. "Detachment levels in the Marathon fold and thrust belt, west Texas." Journal of Structural Geology 49 (April 2013): 23–34. http://dx.doi.org/10.1016/j.jsg.2013.01.007.

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22

Blinova, Maria, Jan Inge Faleide, Roy H. Gabrielsen, and Rolf Mjelde. "Seafloor expression and shallow structure of a fold-and-thrust system, Isfjorden, west Spitsbergen." Polar Research 31, no. 1 (January 2012): 11209. http://dx.doi.org/10.3402/polar.v31i0.11209.

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23

Bergh, Steffen G., and Arild Andresen. "Structural development of the Tertiary fold-and-thrust belt in east Oscar II Land, Spitsbergen." Polar Research 8, no. 2 (January 12, 1990): 217–36. http://dx.doi.org/10.3402/polar.v8i2.6813.

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24

BERGH, STEFFEN G., and ARILD ANDRESEN. "Structural development of the Tertiary fold-and-thrust belt in east Oscar II Land, Spitsbergen." Polar Research 8, no. 2 (December 1990): 217–36. http://dx.doi.org/10.1111/j.1751-8369.1990.tb00385.x.

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25

Evenchick, Carol A. "Structural relationships of the Skeena Fold Belt west of the Bowser Basin, northwest British Columbia." Canadian Journal of Earth Sciences 28, no. 6 (June 1, 1991): 973–83. http://dx.doi.org/10.1139/e91-088.

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The Skeena Fold Belt is a regional fold and thrust belt that extends across most of the width of the northern Intermontane Belt of the Canadian Cordillera. Structural and stratigraphic relationships at its northeast margin show that it developed between latest Jurassic(?) and early Tertiary time, that it involved strata at least as low as Lower and Middle Jurassic Hazelton Group, and that it is characterized by northeast-verging folds and thrust faults. The structures accommodated at least 44% shortening and appear to root to the west.Most of the fold belt is distinguished by folds in thinly layered Jurassic and Cretaceous clastic rocks of the Bowser and Sustut basins. Its boundary is difficult to establish west of the Bowser Basin in poorly layered Middle Jurassic and older strata. However, map relationships show that Hazelton Group strata are folded with Bowser Lake Group. It is suggested here that the fold belt continues westward to the east margin of the Coast Plutonic Complex, where the increase in metamorphic grade and dominance of plutonic rocks effectively mark the western boundary of the Skeena Fold Belt. The difference in structural style between the Bowser Lake Group and massive volcanic rocks of the Hazelton Group is attributed to their difference in competency. Shortening by thrust faults and large-scale folds in volcanic rocks west of the Bowser Basin may balance with shortening by folds and related detachments in Bowser Lake Group farther east.

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26

Dallmann, Winfried K. "The structure of the Berzeliustinden area: evidence for thrust wedge tectonics in the Tertiary fold-and-thrust belt of Spitsbergen." Polar Research 6, no. 2 (January 12, 1988): 141–54. http://dx.doi.org/10.3402/polar.v6i2.6856.

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DALLMANN, WINFRIED K. "The structure of the Berzeliustinden area: Evidence for thrust wedge tectonics in the Tertiary fold-and-thrust belt of Spitsbergen." Polar Research 6, no. 2 (December 1988): 141–54. http://dx.doi.org/10.1111/j.1751-8369.1988.tb00591.x.

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28

SUÁREZ, M., R. DE LA CRUZ, and C. M. BELL. "Timing and origin of deformation along the Patagonian fold and thrust belt." Geological Magazine 137, no. 4 (July 2000): 345–53. http://dx.doi.org/10.1017/s0016756800004192.

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The Andean orogeny in the Patagonian Cordillera of southern South America reflects the consequences of the Mesozoic and Cenozoic subduction of an oceanic plate beneath the South American continental margin. The geological evolution of the region has been influenced by the Eocene collision and subduction of the Farallon–Aluk Ridge and the Miocene–Recent subduction of the Chile Ridge. Another aspect of plate interaction during this period was two intervals of rapid plate convergence, one at 50–42 Ma, and the other at 25–10 Ma, between the South American and the oceanic plates. It has been proposed that the collision of the Chile Ridge with the trench was responsible for the development, at least in part, of the Patagonian fold and thrust belt. This belt extends for more than 1000 km along the eastern foothills of the southern Andes between 46° and 54° S along the southwestern rim of the Austral Basin. The interpretation of a link between subduction of the ridge and formation of the fold and thrust belt is based on assumed time coincidences between contractional tectonism and the collision of ridge segments during Middle and Late Miocene times. The main Tertiary contractional events in the Patagonian fold and thrust belt took place during latest Cretaceous–Palaeocene–Eocene and during Miocene times. Although the timing of deformation is still poorly constrained, the evidence currently available suggests that there is little or no relationship between the timing of the fold and thrust belt and the collision of ridge segments. Most if not all of the contractional tectonism pre-dated the latest episodes of ridge collision. Collision of a ridge crest with the continental margin has been active for the past 14 to 15 million years. Contrary to the suggestion of a relationship between ridge subduction and compression, the main result of this collision has been fast uplift and extensional tectonism. The initiation of the Patagonian fold and thrust belt in latest Cretaceous or early Tertiary times coincided with a fundamental change in the tectonic evolution of the Austral Basin. Throughout the Cretaceous most of this basin subsided as a broad backarc continental shelf. Only in latest Cretaceous times, and coinciding with the initiation of the fold and thrust belt, the basin underwent a transition to a retro-arc foreland basin. This change to an asymmetrically subsiding foreland basin, with an associated foreland fold and thrust belt, was related to uplift of the Andean orogenic belt in the west.

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29

Lacroix, S., and E. W. Sawyer. "An Archean fold-thrust belt in the northwestern Abitibi Greenstone Belt: structural and seismic evidence." Canadian Journal of Earth Sciences 32, no. 2 (February 1, 1995): 97–112. http://dx.doi.org/10.1139/e95-009.

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An integration of structural field data and Lithoprobe seismic reflection line 28 in the northwestern Abitibi Greenstone Belt (AGB) reveals a crustal-scale, south-to southwest-vergent thrusting event that developed "in sequence" above a shallowly (15°) north-dipping sole thrust at a mid-crustal level. Seismic reflector geometry above this décollement suggests a mid crust (6–20 km depth) dominated by low-angle thrusts with smooth trajectory ramps and culmination folds or antiformal stacks, similar to the structural style of neighbouring high-grade plutonic–gneissic (Opatica) and sedimentary (Pontiac) subprovinces. In contrast, low-to high-angle east–west-trending thrusts at the upper-crust greenstone belt level (6–9 km depth) are interpreted to be listric. They occur in two fault systems, the Chicobi and Taibi, that resemble "imbricate fan" systems. The contrasting structural geometry of the upper and mid crust is interpreted as variations in level through the thrust stack, and resembles Paleozoic mountain belts where the upper AGB would represent a ductile–brittle fold–thrust belt. However, the structural evolution of the AGB has been complicated by earlier intrusive–metamorphic contacts or set of thrusts beneath it, and (or) younger out-of-sequence thrusts with north-vergent backthrusts. Also, south-to southwest-vergent thrusts were reactivated, folded, and steepened during a younger dextral strike-slip event.

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Ingram, G. M., T. J. Chisholm, C. J. Grant, C. A. Hedlund, P. Stuart-Smith, and J. Teasdale. "Deepwater North West Borneo: hydrocarbon accumulation in an active fold and thrust belt." Marine and Petroleum Geology 21, no. 7 (August 2004): 879–87. http://dx.doi.org/10.1016/j.marpetgeo.2003.12.007.

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Qureshi, Jahanzeb, Syed Amer Mahmood, Muhammad Khubaib Abuzar, Amer Masood, and Muhammad Shafiq. "Neotectonics of Zindapir Anticline and Sulaiman Fold and Thrust Belt: Inferences from SRTM DEM." International Journal of Economic and Environmental Geology 11, no. 1 (July 7, 2020): 77–82. http://dx.doi.org/10.46660/ijeeg.vol11.iss1.2020.416.

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The current study deals with the significance of surface dynamics (SDs) and its relationship to tectonics and active erosion in Zindapir Anticline (ZPA) and neighboring Sulaiman Fold and Thrust Belt (SFTB) which is a direct result of transform plate movement between Indo-Pak continent and Eurasia. The Shuttle Radar Topographic Mission Digital Elevation Model SRTM DEM with 30 m resolution was employed to compute SDs; Isobase (IBL), drainage density (DD), relative relief (RR) and vertical dissection (VD) thematic maps for the study area. The results obtained show that the DD, RR, VD and IBL have higher values in north west, central segments and south west of the SFTB, whereas the Zindapir anticline represents dextral movement on its east side while sinistral sense of movement is observed on its western edge. High values of RR and VD correspond to highly incised topography with great surface roughness. The enhanced values of IBL and DD in the northwest, south west and central SFTB correspond to uplifted active topography segments and can trigger medium level earthquakes in this region. The conjugate movement of ZPA is an indication of its neotectonic nature and recent uplift is causing surface deformation which needs to be understood in the context of SFTB development as a result of India-Eurasia transform movement

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Qureshi, Jahanzeb, Syed Amer Mahmood, Muhammad Khubaib Abuzar, Amer Masood, and Muhammad Shafiq. "Neotectonics of Zindapir Anticline and Sulaiman Fold and Thrust Belt: Inferences from SRTM DEM." International Journal of Economic and Environmental Geology 11, no. 1 (July 7, 2020): 77–82. http://dx.doi.org/10.46660/ojs.v11i1.416.

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The current study deals with the significance of surface dynamics (SDs) and its relationship to tectonics and active erosion in Zindapir Anticline (ZPA) and neighboring Sulaiman Fold and Thrust Belt (SFTB) which is a direct result of transform plate movement between Indo-Pak continent and Eurasia. The Shuttle Radar Topographic Mission Digital Elevation Model SRTM DEM with 30 m resolution was employed to compute SDs; Isobase (IBL), drainage density (DD), relative relief (RR) and vertical dissection (VD) thematic maps for the study area. The results obtained show that the DD, RR, VD and IBL have higher values in north west, central segments and south west of the SFTB, whereas the Zindapir anticline represents dextral movement on its east side while sinistral sense of movement is observed on its western edge. High values of RR and VD correspond to highly incised topography with great surface roughness. The enhanced values of IBL and DD in the northwest, south west and central SFTB correspond to uplifted active topography segments and can trigger medium level earthquakes in this region. The conjugate movement of ZPA is an indication of its neotectonic nature and recent uplift is causing surface deformation which needs to be understood in the context of SFTB development as a result of India-Eurasia transform movement

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FUENTES, FACUNDO, BRIAN K. HORTON, DANIEL STARCK, and ANDRÉS BOLL. "Structure and tectonic evolution of hybrid thick- and thin-skinned systems in the Malargüe fold–thrust belt, Neuquén basin, Argentina." Geological Magazine 153, no. 5-6 (July 25, 2016): 1066–84. http://dx.doi.org/10.1017/s0016756816000583.

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AbstractAndean Cenozoic shortening within the Malargüe fold–thrust belt of west-central Argentina has been dominated by basement faults largely influenced by pre-existing Mesozoic rift structures of the Neuquén basin system. The basement contractional structures, however, diverge from many classic inversion geometries in that they formed large hanging-wall anticlines with steeply dipping frontal forelimbs and structural relief in the order of several kilometres. During Cenozoic E–W shortening, the reactivated basement faults propagated into cover strata, feeding slip to shallow thrust systems that were later carried in piggyback fashion above newly formed basement structures, yielding complex thick- and thin-skinned structural relationships. In the adjacent foreland, Cenozoic clastic strata recorded the broad kinematic evolution of the fold–thrust belt. We present a set of structural cross-sections supported by regional surface maps and industry seismic and well data, along with new stratigraphic information for associated Neogene synorogenic foreland basin fill. Collectively, these results provide important constraints on the temporal and geometric linkages between the deeper basement faults (including both reactivated and newly formed structures) and shallow thin-skinned thrust systems, which, in turn, offer insights for the understanding of hydrocarbon systems in the actively explored Neuquén region of the Andean orogenic belt.

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Gao, Zihui, Nicholas D. Perez, Brent Miller, and Michael C. Pope. "Competing sediment sources during Paleozoic closure of the Marathon-Ouachita remnant ocean basin." GSA Bulletin 132, no. 1-2 (July 15, 2019): 3–16. http://dx.doi.org/10.1130/b35201.1.

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Abstract The Paleozoic construction of Pangea advanced southwestward from the Appalachian system to the Marathon fold-and-thrust belt in west Texas and progressively closed a remnant ocean basin between Laurentia and Gondwana. The resulting collisional orogen was a potential driver of Ancestral Rocky Mountain tectonism and impacted continental-scale sediment routing. New detrital zircon U-Pb geochronologic and heavy mineral provenance data from Ordovician–Pennsylvanian strata in the Marathon fold-and-thrust belt, and Permian strata in the Guadalupe Mountains of west Texas record changes in sediment provenance during the tectonic development of southwestern Laurentia and the Delaware Basin. In the Marathon fold-and-thrust belt, Ordovician rocks (Woods Hollow and Marathon Formations) record peri-Gondwanan sediment sources prior to continent collision. Syncollisional Mississippian and Pennsylvanian rocks (Tesnus, Haymond, Gaptank Formations) record contributions from distal Appalachian sources, recycled material from the active continental suture, and volcanic arc material from Gondwana. Near the Guadalupe Mountains, postcollisional Permian strata (Delaware Mountain Group) from the northern Delaware Basin margin suggest a dominantly southern catchment that was sourced from the deforming suture and Gondwanan arc. The results demonstrate that both plates and the active suture zone were sources for the siliciclastic wedge, but their proportions differed through time. These results also suggest that the delay between initial late Mississippian suturing in the Marathon region and increased mid-Permian siliciclastic deposition into the northern Delaware Basin may have been linked to a southward catchment expansion that integrated the collisional belt and southern volcanic arc into a broadly north-directed sediment dispersal system.

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Greene, David C. "The Confusion Range, west-central Utah: Fold-thrust deformation and a western Utah thrust belt in the Sevier hinterland." Geosphere 10, no. 1 (February 2014): 148–69. http://dx.doi.org/10.1130/ges00972.1.

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Knapp, James H., and Matthew T. Heizler. "Thermal history of crystalline nappes of the Maria Fold and Thrust Belt, west central Arizona." Journal of Geophysical Research 95, B12 (1990): 20049. http://dx.doi.org/10.1029/jb095ib12p20049.

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37

El-Shafei, Mohamed K. "Thrust duplex deformation in the volcaniclastic sequence of the Fatima fold-and-thrust belt in the west-central Arabian Shield." Journal of Asian Earth Sciences 138 (May 2017): 211–29. http://dx.doi.org/10.1016/j.jseaes.2017.02.007.

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38

Abdullah, Rashed, Md Shahadat Hossain, Md Soyeb Aktar, Mohammad Moinul Hossain, and Farida Khanam. "Structural initiation along the frontal fold-thrust system in the western Indo-Burman Range: Implications for the tectonostratigraphic evolution of the Hatia Trough (Bengal Basin)." Interpretation 9, no. 3 (July 27, 2021): SF1—SF10. http://dx.doi.org/10.1190/int-2020-0227.1.

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The Bengal Basin accommodates an extremely thick Cenozoic sedimentary succession that derived from the uplifted Himalayan and Indo-Burman Orogenic Belts in response to the subduction of the Indian Plate beneath the Eurasian and Burmese Plates. The Hatia Trough is a proven petroleum province that occupies much of the southern Bengal Basin. However, the style of deformation, kinematics, and possible timing of structural initiation in the Hatia Trough and the relationship of this deformation to the frontal fold-thrust system in the outer wedge (namely, the Chittagong Tripura Fold Belt) of the Indo-Burman subduction system to the east are largely unknown. Therefore, we have carried out a structural interpretation across the eastern Hatia Trough and the western Chittagong Tripura Fold Belt based on 2D seismic reflection data. Our result suggests that the synkinematic packages correspond to the Pliocene Tipam Group and the Pleistocene Dupitila Formation. This implies that the structural development in the western Chittagong Tripura Fold Belt took place from the Pliocene. In the Hatia Trough, the timing of structural activation is slightly later (since the Plio-Pleistocene). In general, fold intensity and structural complexity gradually increase toward the east. The presence of reverse faults with minor strike-slip motion along the frontal thrust system in the outer wedge is also consistent with the regional transpressional structures of the Indo-Burman subduction system. However, to the west, there is no evidence for strike-slip deformation in the Hatia Trough. The restored sections indicate that the amount of east–west shortening in the Hatia Trough is very low (maximum 1.2%). In contrast, to the east, the amount of shortening is high (maximum 13.5%) in the western margin of the Chittagong Tripura Fold Belt. In both areas, the key trapping mechanism includes anticlinal traps, although stratigraphic and combinational traps are possible, but this requires further evaluation.

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Remus, David, and Karen Tindale. "THE PLEASANT CREEK ARCH, ADAVALE BASIN, A MID DEVONIAN TO MID CARBONIFEROUS THRUST SYSTEM." APPEA Journal 28, no. 1 (1988): 208. http://dx.doi.org/10.1071/aj87017.

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Interpretation of recently acquired multifold seismic data has led to a reappraisal of the structural evolution of the Adavale Basin with particular reference to the Pleasant Creek Arch.The Basin initially formed as a back arc basin to the west of the Anakie/Nebine volcanic arc. Three stages of tectonic evolution are recognised; rifting, extension and convergence. The Pleasant Creek Arch represents a foreland fold belt cratonward of the major convergent margin deformational zone.The model proposed for the development of the Pleasant Creek Arch is a buried to weakly emergent foreland thrust system modified by Late Carboniferous erosion. This was subsequently covered by sediments of the Galilee and Eromanga Basins. Late to Middle Devonian sediments are involved in thrusting that exhibits two styles of deformation. Along the southern 70 km of the thrust front Lower to Middle Devonian sediments are thrust under an upper decollement forming a passive roof duplex or backthrust zone. The Boree Salt acts as this upper decollement. The thrust tipline is controlled by the western depositional edge of the salt. North of this area the thrust appears to have been weakly emergent. Proprietary and open file seismic data from ATP's 301P, 304P and 305P and surrounding permits are used to illustrate the model. Comparisons can be made between this model and similar thrust systems in the Canadian Rocky and Mackenzie Mountains, the Appalachian Plateau, the Southern Norwegian Caledonides, the Kirthar and Sulaiman Mountain ranges of Pakistan and the Papua New Guinea fold belt.

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Mukul, Malay. "The geometry and kinematics of the Main Boundary Thrust and related neotectonics in the Darjiling Himalayan fold-and-thrust belt, West Bengal, India." Journal of Structural Geology 22, no. 9 (September 2000): 1261–83. http://dx.doi.org/10.1016/s0191-8141(00)00032-8.

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41

Kamberis, E., S. Sotiropoulos, F. Marnelis, and N. Rigakis. "Thrust tectonics in the central part of the External Hellenides, the case of the Gavrovo thrust." Bulletin of the Geological Society of Greece 47, no. 2 (January 24, 2017): 540. http://dx.doi.org/10.12681/bgsg.11081.

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Thrust faulting plays an important role in the structural deformation of Gavrovo and Ionian zones in the central part of the ‘External Hellenides’ fold-and-thrust belt. The Skolis mountain in NW Peloponnese as well as the Varassova and Klokova mountains in Etoloakarnania are representative cases of ramp anticlines associated with the Gavrovo thrust. Surface geology, stratigraphic data and interpretation of seismic profiles indicate that it is a crustal-scale thrust acted throughout the Oligocene time. It is characterized by a ramp-flat geometry and significant displacement (greater than 10 km). Out of sequence thrust segmentation is inferred in south Etoloakarnania area. Down flexure and extensional faulting in the Ionian zone facilitated the thrust propagation to the west. The thrust emplacement triggered halokenetic movement of the Triassic evaporites in the Ionian zone as well as diapirisms that were developed in a later stage in the vicinity of the Skolis mountain.

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42

Motta, João Gabriel, Norberto Morales, and Walter Malagutti Filho. "Geophysical perspective on the structural interference zone along the Neoproterozoic Brasília and Ribeira fold belts in West Gondwana." Brazilian Journal of Geology 47, no. 1 (January 2017): 3–19. http://dx.doi.org/10.1590/2317-4889201720160144.

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ABSTRACT: The Brasília and Ribeira fold belts have been established in south-southwestern São Francisco Craton during the Brasiliano-Pan African orogeny (0.9-0.5 Ga - Tonian to Cambrian), and played an important role in West Gondwana continent assembly. The region is given by a complex regional fold and thrust belt superposed by shearing during the orogeny late times, with superposing stress fields forming a structural interference zone. These thrust sheets encompasses assemblies from lower- to upper-crust from different major tectonic blocks (Paranapanema, São Francisco), and newly created metamorphic rocks. Re-evaluation of ground gravity datasets in a geologically constrained approach including seismology (CRUST1 model) and magnetic data (EMAG2 model) unveiled details on the deep- crust settings, and the overall geometry of the structural interference zone. The Simple Bouguer Anomaly map shows heterogeneous density distribution in the area, highlighting the presence of high-density, high metamorphic grade rocks along the Alterosa suture zone in the Socorro-Guaxupé Nappe, lying amid a series of metasedimentary thrust scales in a regional nappe system with important verticalization along regional shear zones. Forward gravity modeling favors interpretations of structural interference up North into Guaxupé Nappe. Comparison to geotectonic models shows similarities with modern accretionary belts, renewing the discussion.

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Cheng, Feng, Andrew V. Zuza, Peter J. Haproff, Chen Wu, Christina Neudorf, Hong Chang, Xiangzhong Li, and Bing Li. "Accommodation of India–Asia convergence via strike-slip faulting and block rotation in the Qilian Shan fold–thrust belt, northern margin of the Tibetan Plateau." Journal of the Geological Society 178, no. 3 (January 29, 2021): jgs2020–207. http://dx.doi.org/10.1144/jgs2020-207.

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Existing models of intracontinental deformation have focused on plate-like rigid body motion v. viscous-flow-like distributed deformation. To elucidate how plate convergence is accommodated by intracontinental strike-slip faulting and block rotation within a fold–thrust belt, we examine the Cenozoic structural framework of the central Qilian Shan of northeastern Tibet, where the NW-striking, right-slip Elashan and Riyueshan faults terminate at the WNW-striking, left-slip Haiyuan and Kunlun faults. Field- and satellite-based observations of discrete right-slip fault segments, releasing bends, horsetail termination splays and off-fault normal faulting suggest that the right-slip faults accommodate block rotation and distributed west–east crustal stretching between the Haiyuan and Kunlun faults. Luminescence dating of offset terrace risers along the Riyueshan fault yields a Quaternary slip rate of c. 1.1 mm a−1, which is similar to previous estimates. By integrating our results with regional deformation constraints, we propose that the pattern of Cenozoic deformation in northeastern Tibet is compatible with west–east crustal stretching/lateral displacement, non-rigid off-fault deformation and broad clockwise rotation and bookshelf faulting, which together accommodate NE–SW India–Asia convergence. In this model, the faults represent strain localization that approximates continuum deformation during regional clockwise lithospheric flow against the rigid Eurasian continent.Supplementary material: Luminescence dating procedures and protocols is available at https://doi.org/10.17605/OSF.IO/CR9MNThematic collection: This article is part of the Fold-and-thrust belts and associated basins collection available at: https://www.lyellcollection.org/cc/fold-and-thrust-belts

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Riesner, M., R. Lacassin, M. Simoes, R. Armijo, R. Rauld, and G. Vargas. "Kinematics of the active West Andean fold-and-thrust belt (central Chile): Structure and long-term shortening rate." Tectonics 36, no. 2 (February 2017): 287–303. http://dx.doi.org/10.1002/2016tc004269.

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Relf, C. "Two distinct shortening events during late Archean orogeny in the west-central Slave Province, Northwest Territories, Canada." Canadian Journal of Earth Sciences 29, no. 10 (October 1, 1992): 2104–17. http://dx.doi.org/10.1139/e92-167.

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Late Archean structures in the west-central part of the Slave Province formed during two separate orogenic events. Evidence for early folding and thrusting in an accretionary prism is confined to a narrow belt along the east margin of an older microcontinent (the Anton terrane) in the west part of the province. Structures related to this event are overprinted by regional low-pressure metamorphism. Subsequent shortening occurred in a continental-arc setting in which folding and faulting was accompanied by calc-alkaline magmatism and regional low-pressure metamorphism. Although the entire region was affected, the bulk of shortening during the second orogenic event occurred east of the early fold and thrust belt. The first orogenic event produced a suture zone between old continental crust to the west and juvenile rocks to the east, and during the second orogenic event rocks on either sides of the suture were tectonically underplated and intruded.

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Malekzade, Zaman, Olivier Bellier, Mohammad Reza Abbassi, Esmaiel Shabanian, and Christine Authemayou. "The effects of plate margin inhomogeneity on the deformation pattern within west-Central Zagros Fold-and-Thrust Belt." Tectonophysics 693 (December 2016): 304–26. http://dx.doi.org/10.1016/j.tecto.2016.01.030.

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Lammie, Daniel, Nadine McQuarrie, and Peter B. Sak. "Quantifying shortening across the central Appalachian fold-thrust belt, Virginia and West Virginia, USA: Reconciling grain-, outcrop-, and map-scale shortening." Geosphere 16, no. 5 (August 10, 2020): 1276–92. http://dx.doi.org/10.1130/ges02016.1.

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Abstract We present a kinematic model for the evolution of the central Appalachian fold-thrust belt (eastern United States) along a transect through the western flank of the Pennsylvania salient. New map and strain data are used to construct a balanced geologic cross section spanning 274 km from the western Great Valley of Virginia northwest across the Burning Spring anticline to the undeformed foreland of the Appalachian Plateau of West Virginia. Forty (40) oriented samples and measurements of >300 joint orientations were collected from the Appalachian Plateau and Valley and Ridge province for grain-scale bulk finite strain analysis and paleo-stress reconstruction, respectively. The central Appalachian fold-thrust belt is characterized by a passive-roof duplex, and as such, the total shortening accommodated by the sequence above the roof thrust must equal the shortening accommodated within duplexes. Earlier attempts at balancing geologic cross sections through the central Appalachians have relied upon unquantified layer-parallel shortening (LPS) to reconcile the discrepancy in restored line lengths of the imbricated carbonate sequence and mainly folded cover strata. Independent measurement of grain-scale bulk finite strain on 40 oriented samples obtained along the transect yield a transect-wide average of 10% LPS with province-wide mean values of 12% and 9% LPS for the Appalachian Plateau and Valley and Ridge, respectively. These values are used to evaluate a balanced cross section, which shows a total shortening of 56 km (18%). Measured magnitudes of LPS are highly variable, as high as 17% in the Valley and Ridge and 23% on the Appalachian Plateau. In the Valley and Ridge province, the structures that accommodate shortening vary through the stratigraphic package. In the lower Paleozoic carbonate sequences, shortening is accommodated by fault repetition (duplexing) of stratigraphic layers. In the interval between the duplex (which repeats Cambrian through Upper Ordovician strata) and Middle Devonian and younger (Permian) strata that shortened through folding and LPS, there is a zone that is both folded and faulted. Across the Appalachian Plateau, slip is transferred from the Valley and Ridge passive-roof duplex to the Appalachian Plateau along the Wills Mountain thrust. This shortening is accommodated through faulting of Upper Ordovician to Lower Devonian strata and LPS and folding within the overlying Middle Devonian through Permian rocks. The significant difference between LPS strain (10%–12%) and cross section shortening estimates (18% shortening) highlights that shortening from major subsurface faults within the central Appalachians of West Virginia is not easily linked to shortening in surface folds. Depending on length scale over which the variability in LPS can be applied, LPS can accommodate 50% to 90% of the observed shortening; other mechanisms, such as outcrop-scale shortening, are required to balance the proposed model.

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Harsolumakso, Agus Handoyo, Benyamin Sapiie, Alfend Rudyawan, Herwin Tiranda, Ezidin Reski, and Reni Fauziah. "Understanding Structural Style of Onshore Timor Basin from Detailed Fieldwork." Modern Applied Science 13, no. 4 (March 31, 2019): 123. http://dx.doi.org/10.5539/mas.v13n4p123.

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Hydrocarbon exploration in Eastern Indonesia region is mainly concentrated in the related convergent area such as Timor Basin. This area is characterized by the development of complex imbricate thrust-fold-belt deformation involving sedimentary sequence from the Australia continental margin. However, the exploration has not been successfully found the potential economic reserve. Our study utilized extensive and detailed fieldwork campaign  presents the structural style on the onshore region of the Timor Basin. Thick-skinned and thin-skinned thrust faults are both presents in West Timor area divided by the syn-orogenic basin. The change in decolement surface is likely to be caused by inversion structures under the thrust sheets. Our present interpretations indicate that these inversion anticlines structure are likely to occur both onshore and offshore.

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Manby, G. M. "Mid-Palaeozoic metamorphism and polyphase deformation of the Forland Complex, Svalbard." Geological Magazine 123, no. 6 (November 1986): 651–63. http://dx.doi.org/10.1017/s001675680002416x.

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AbstractThe Forland Complex of Prins Karls Forland has been subjected to mid-Palaeozoic greenschist facies metamorphism and polyphase deformation. Metamorphism was initiated prior to D1 deformation and gave rise to a parallelism of stratigraphic and metamorphic reaction surfaces. D1 gave rise to imbricately thrust, southwest-directed fold nappes which have not noticeably disturbed the isograd surfaces. D2, interpreted as belonging to the mid-Cenozoic West Spitsbergen Orogeny (WSO) which was coaxial but not coplanar with D1, produced crenulation folds and pressure solution cleavages and some thrusting. D3 structures are related to the formation of the Prins Karls Forland–Forlandsundet–Oscar II horst and graben system which is a late expression of the WSO. The rejuvenation of the Prins Karls Forland horst along NNW–SSE faults, the large scale E–W flexures and ENE–WSW faults in the Forland Complex and Tertiary graben deposits are assigned to D3.

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Grocott, John, and Kenneth J. W. McCaffrey. "Basin evolution and destruction in an Early Proterozoic continental margin: the Rinkian fold–thrust belt of central West Greenland." Journal of the Geological Society 174, no. 3 (January 27, 2017): 453–67. http://dx.doi.org/10.1144/jgs2016-109.

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Journal articles on the topic 'West Spitsbergen Fold-and-Thrust Belt'

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