Thrust duplex deformation in the volcaniclastic sequence of the Fatima fold-and-thrust belt in the west-central Arabian Shield

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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The Amer Belt: remnant of an Aphebian foreland fold and thrust belt

Canadian Journal of Earth Sciences ◽

10.1139/e86-186 ◽

1986 ◽

Vol 23 (12) ◽

pp. 2012-2023 ◽

Cited By ~ 18

Author(s):

Judith G. Patterson

Keyword(s):

Normal Faults ◽

Lake Area ◽

Thrust Belt ◽

East Side ◽

Progressive Deformation ◽

The West ◽

Polyphase Deformation ◽

Thrust Belts ◽

Fold And Thrust Belt ◽

Stratigraphic Model

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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The effects of plate margin inhomogeneity on the deformation pattern within west-Central Zagros Fold-and-Thrust Belt

Tectonophysics ◽

10.1016/j.tecto.2016.01.030 ◽

2016 ◽

Vol 693 ◽

pp. 304-326 ◽

Cited By ~ 14

Author(s):

Zaman Malekzade ◽

Olivier Bellier ◽

Mohammad Reza Abbassi ◽

Esmaiel Shabanian ◽

Christine Authemayou

Keyword(s):

Deformation Pattern ◽

Thrust Belt ◽

Plate Margin ◽

West Central ◽

Fold And Thrust Belt

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Regional rock quality designation (RRQD) of the west central Arabian Shield

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts ◽

10.1016/0148-9062(94)91069-3 ◽

1994 ◽

Vol 31 (4) ◽

pp. 193

Keyword(s):

Arabian Shield ◽

Rock Quality Designation ◽

The West ◽

Rock Quality ◽

West Central

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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 ◽

10.1017/s0016756817001145 ◽

2018 ◽

Vol 156 (4) ◽

pp. 620-638 ◽

Cited By ~ 2

Author(s):

KATARZYNA DUDZISZ ◽

KRZYSZTOF MICHALSKI ◽

RAFAŁ SZANIAWSKI ◽

KRZYSZTOF NEJBERT ◽

GEOFFREY MANBY

Keyword(s):

Remanent Magnetization ◽

Vitrinite Reflectance ◽

Lower Triassic ◽

Natural Remanent Magnetization ◽

The Other ◽

Thrust Belt ◽

The West ◽

Fold And Thrust Belt ◽

Oriented Samples ◽

West Spitsbergen

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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Two distinct shortening events during late Archean orogeny in the west-central Slave Province, Northwest Territories, Canada

Canadian Journal of Earth Sciences ◽

10.1139/e92-167 ◽

1992 ◽

Vol 29 (10) ◽

pp. 2104-2117 ◽

Cited By ~ 11

Author(s):

C. Relf

Keyword(s):

Accretionary Prism ◽

Low Pressure ◽

Alkaline Magmatism ◽

The West ◽

Slave Province ◽

West Central ◽

Fold And Thrust Belt ◽

West Part ◽

Arc Setting ◽

Narrow Belt

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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