Unravelling metamorphic ages of suture zone rocks from the Sabzevar and Makran areas (Iran): robust age constraints for the larger Arabia‐Eurasian collision zone

Abstract. Stratigraphy, detailed structural mapping and a crustal-scale cross section across the NW Zagros collision zone provide constraints on the spatial evolution of oblique convergence of the Arabian and Eurasian plates since the Late Cretaceous. The Zagros collision zone in NW Iran consists of the internal Sanandaj–Sirjan, Gaveh Rud and Ophiolite zones and the external Bisotoun, Radiolarite and High Zagros zones. The Main Zagros Thrust is the major structure of the Zagros suture zone. Two stages of oblique deformation are recognized in the external part of the NW Zagros in Iran. In the early stage, coexisting dextral strike-slip and reverse dominated domains in the Radiolarite zone developed in response to deformation partitioning due to oblique convergence. Dextral-reverse faults in the Bisotoun zone are also compatible with oblique convergence. In the late stage, deformation partitioning occurred during southeastward propagation of the Zagros orogeny towards its foreland resulting in synchronous development of orogen-parallel strike-slip and thrust faults. It is proposed that the first stage was related to Late Cretaceous oblique obduction, while the second stage resulted from Cenozoic collision. The Cenozoic orogen-parallel strike-slip component of Zagros oblique convergence is not confined to the Zagros suture zone (Main Recent Fault) but also occurred in the external part (Marekhil–Ravansar fault system). Thus, it is proposed that oblique convergence of Arabian and Eurasian plates in Zagros collision zone initiated with oblique obduction in the Late Cretaceous followed by oblique collision in the late Tertiary, consistent with global plate reconstructions.

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First40Ar/39Ar age constraints for the Caledonian evolution of the Trans–European Suture Zone in NE Germany

Journal of the Geological Society ◽

10.1144/gsjgs.156.2.0279 ◽

1999 ◽

Vol 156 (2) ◽

pp. 279-290 ◽

Cited By ~ 25

Author(s):

R. D. DALLMEYER ◽

U. GIESE ◽

U. GLASMACHER ◽

W. PICKEL

Keyword(s):

Suture Zone ◽

Ne Germany ◽

Age Constraints

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Spatial evolution of Zagros collision zone in Kurdistan – NW Iran, constraints for Arabia–Eurasia oblique convergence

Solid Earth Discussions ◽

10.5194/sed-7-2735-2015 ◽

2015 ◽

Vol 7 (3) ◽

pp. 2735-2773 ◽

Cited By ~ 2

Author(s):

S. Sadeghi ◽

A. Yassaghi

Keyword(s):

Late Cretaceous ◽

Early Stage ◽

Strike Slip ◽

Suture Zone ◽

Fault System ◽

Spatial Evolution ◽

Nw Iran ◽

Collision Zone ◽

Oblique Convergence ◽

Synchronous Development

Abstract. Stratigraphy, detailed structural mapping and crustal scale cross section of the NW Zagros collision zone evolved during convergence of the Arabian and Eurasian plates were conducted to constrain the spatial evolution of the belt oblique convergence since Late Cretaceous. Zagros orogeny in NW Iran consists of the Sanandaj–Sirjan, Gaveh Rud and ophiolite zones as internal, and Bisotoun, Radiolarite and High Zagros zones as external parts. The Main Zagros Thrust is known as major structures of the Zagros suture zone. Two stages of deformation are recognized in the external parts of Zagros. In the early stage, presence of dextrally deformed domains beside the reversely deformed domains in the Radiolarite zone as well as dextral-reverse faults in both Bisotoun and Radiolarite zones demonstrates partitioning of the dextral transpression. In the late stage, southeastward propagation of the Zagros orogeny towards its foreland resulted in synchronous development of orogen-parallel strike-slip and pure thrust faults. It is proposed that the first stage related to the late Cretaceous oblique obduction, and the second stage is resulted from Cenozoic collision. Cenozoic orogen-parallel strike-slip component of Zagros oblique faulting is not confined to the Zagros suture zone (Main Recent) but also occurred in the more external part (Marekhil–Ravansar fault system). Thus, it is proposed that oblique convergence of Arabia–Eurasia plates occurred in Zagros collision zone since the Late Cretaceous.

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Geochemical and zircon U–Pb age constraints on the origin of the Mesozoic Xigaze ophiolite, Yarlung Zangbo suture zone, SW China

International Geology Review ◽

10.1080/00206814.2017.1385034 ◽

2017 ◽

Vol 60 (10) ◽

pp. 1267-1289 ◽

Cited By ~ 5

Author(s):

Xi-chen Wang ◽

Wei-liang Liu ◽

Yun Zhong ◽

Xi-chong Hu ◽

Bin Xia ◽

...

Keyword(s):

Suture Zone ◽

Sw China ◽

Age Constraints ◽

Yarlung Zangbo Suture Zone

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Collision zone between the Kohistan arc and the Asian plate in NW Pakistan

Transactions of the Royal Society of Edinburgh Earth Sciences ◽

10.1017/s026359330001066x ◽

1985 ◽

Vol 76 (4) ◽

pp. 463-479 ◽

Cited By ~ 71

Author(s):

C. J. Pudsey ◽

M. P. Coward ◽

I. W. Luff ◽

R. M. Shackleton ◽

B. F. Windley ◽

...

Keyword(s):

Volcanic Rocks ◽

Deep Levels ◽

Suture Zone ◽

Island Arc ◽

Central Unit ◽

Volcanic Group ◽

Collision Zone ◽

Structural History ◽

History Of ◽

Layered Complex

ABSTRACTThis paper describes the suture zone between the Asian plate and the accreted Kohistan island arc in the Chitral district of NW Pakistan.The southern part of the Asian plate consists of two tectonic units separated by the N-dipping Reshun fault. The northwestern unit comprises Devonian carbonates and quartzites overlain by Devonian to Permian shales and slates with some limestones (Lun shales). Its structure is complex with S-verging thrusts and isoclinal folds. Along the Reshun fault, the relatively undeformed Reshun Formation may represent molasse. The central unit includes N-dipping Upper Palaeozoic slates and quartzites (Darkot Group), probably faulted against an antiformal tract of slates, schists derived from a volcanic assemblage and Cretaceous limestones (Chitral slate, Koghozi greenschist, Krinj and Gahiret limestones). Asian plate sediments are intruded by granitic and granodioritic plutons, variably deformed and locally porphyritic.The Northern suture melange of volcanic, sedimentary and serpentinite blocks in a slate matrix separates the Asian plate from the southeastern unit, the Kohistan arc. This comprises Cretaceous volcanic rocks with some sediments (Shamran Volcanic Group, Drosh, Purit and Gawuch Formations) intruded by aphyric diorites, tonalites and granites. These intermediate plutonic rocks pass southwards into a mafic layered complex and amphibolites representing deep levels of the arc. The volcanic rocks and sediments dip to the N and have a horizontal lineation. The structural history of southern Asia and Kohistan is consistent with an originally curved Northern suture: motion of the arc was initially to the NE relative to Asia and subsequently to the NW.

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