THE PLEASANT CREEK ARCH, ADAVALE BASIN, A MID DEVONIAN TO MID CARBONIFEROUS THRUST SYSTEM

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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The Mesozoic–Cenozoic tectonic evolution of the New Siberian Islands, NE Russia

Geological Magazine ◽

10.1017/s0016756814000326 ◽

2014 ◽

Vol 152 (3) ◽

pp. 480-491 ◽

Cited By ~ 8

Author(s):

CHRISTIAN BRANDES ◽

KARSTEN PIEPJOHN ◽

DIETER FRANKE ◽

NIKOLAY SOBOLEV ◽

CHRISTOPH GAEDICKE

Keyword(s):

Tectonic Evolution ◽

Structural Evolution ◽

Arctic Shelf ◽

Laptev Sea ◽

Russian Arctic ◽

Thrust Belt ◽

Fold Belt ◽

New Siberian Islands ◽

Ne Russia ◽

The Laptev Sea

AbstractOn the New Siberian Islands the rocks of the east Russian Arctic shelf are exposed and allow an assessment of the structural evolution of the region. Tectonic fabrics provide evidence of three palaeo-shortening directions (NE–SW, WNW–ESE and NNW–SSE to NNE–SSW) and one set of palaeo-extension directions revealed a NE–SW to NNE–SSW direction. The contractional deformation is most likely the expression of the Cretaceous formation of the South Anyui fold–thrust belt. The NE–SW shortening is the most prominent tectonic phase in the study area. The WNW–ESE and NNW–SSE to NNE–SSW-oriented palaeo-shortening directions are also most likely related to fold belt formation; the latter might also have resulted from a bend in the suture zone. The younger Cenozoic NE–SW to NNE–SSW extensional direction is interpreted as a consequence of rifting in the Laptev Sea.

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TECTONIC EVOLUTION OF THE BETIC CORDILLERA: AN OVERVIEW

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.16563 ◽

2004 ◽

Vol 36 (4) ◽

pp. 1598 ◽

Cited By ~ 5

Author(s):

F. Alonso-Chaves ◽

J. I. Soto ◽

M. Orozco ◽

A. A. Kilias ◽

M. D. Tranos

Keyword(s):

Tectonic Evolution ◽

Aegean Sea ◽

Normal Faults ◽

The South ◽

Mountain Ranges ◽

The North ◽

Arc Setting ◽

The One ◽

Continental Basin ◽

Back Arc

The Betic (Southern Spain) and the Rif (Morocco) mountain chains, connected through the Gibraltar Strait, shapes a W-E elongated and arcuate Alpine orogenic belt. The Alborân Sea, in continuity to the east with the South Balearic Basin, is located in the inner part of this alpine belt. The Iberian and African continental forelands bound the region as a whole to the north and south, respectively, and to the east it is connected to the oceanic Sardine-Balearic Basin. The peculiarities of these westernmost Mediterranean chains result from: (1) its position between two large convergent plates -Africa and Europe- that have had variable directions of relative motion since the late Cretaceous; and (2) the Neogene westward migration of the orogenic hinterland and its simultaneous "back-arc"-like extension, generating the Alborén Sea basin. The complexes and large paleogeographic terrains traditionally recognized in the Betic and Rif chains belong to four pre-Neogene crustal domains: the South-Iberian and Maghrebian passive continental paleomargins (External Zones of the orogen), the Flysch Units, and the Alborân Crustal Domain composed mainly of a pre- Miocene metamorphosed thrust-stack (Nevado-Filabride, Alpujârride, and Malaguide complexes, from bottom to top). The boundaries between the main metamorphic complexes of the Alborân Domain are extensional detachments, which finally developed under brittle conditions and are commonly sealed by middle-to-late Miocene marine-to-continental sediments. They, nonetheless, are not the most recent structures in the Alborân Domain, because upright, E-W open folds warp the extensional detachments, and finally, high-angle normal faults and strike-slip faults, many of which are still active, offset folds and extensional detachments. The tectonic evolution of the Betic Alborân orogenic system shows close similarities with the one depicted in other arcuate-shaped, Alpine mountain ranges in the Mediterranean, such as the Hellenic Arc and the Aegean Sea. Like in the westernmost Mediterranean, a thickened (pre Miocene) crust is bounding there a thinned, continental (?) basin. Extension is also formed here in a "back-arc" setting, being developed simultaneously with the N-S convergence between the African and European plates.

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Structural evolution in the Moine of northwest Scotland: a Caledonian linked thrust system?

Geological Magazine ◽

10.1017/s0016756800026492 ◽

1986 ◽

Vol 123 (1) ◽

pp. 1-11 ◽

Cited By ~ 21

Author(s):

Robert W. H. Butler

Keyword(s):

Cross Sections ◽

Lower Crust ◽

Structural Evolution ◽

Amphibolite Facies ◽

Metamorphic Basement ◽

Thrust System ◽

Lower Crustal

AbstractA model is proposed whereby the Caledonian metamorphic basement-cover complex of northwest Scotland (the Moine) is considered as a linked thrust system. This system lies between the Moine thrust at its base and the Naver–Sgurr Beag slide at its top. Ductile fold and thrust zones, which developed at mid crustal levels at metamorphic grades from greenschist to amphibolite facies, are interpreted as decoupling from a detachment presently situated at relatively shallow depths. This model is illustrated by two preliminary balanced cross-sections. These imply shortening across the northwest Scottish Caledonides in excess of 130 km and probably over 200 km. When these structures are restored onto a crustal template a considerable quantity of lower crust is found to be required at depth. The most likely location for the lower crustal wedge is beneath the Grampian Highlands.

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Tectonic evolution of the west Spitsbergen fold belt

Tectonophysics ◽

10.1016/0040-1951(85)90013-7 ◽

1985 ◽

Vol 114 (1-4) ◽

pp. 193-211 ◽

Cited By ~ 17

Author(s):

C. Craddock ◽

E.C. Hauser ◽

H.D. Maher ◽

A.Y. Sun ◽

Zhu Guo-Qiang

Keyword(s):

Tectonic Evolution ◽

Fold Belt ◽

The West ◽

West Spitsbergen

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Structural evolution of shale diapirs from reactive rise to mud volcanism: 3D seismic data from the Baram delta, offshore Brunei Darussalam

Journal of the Geological Society ◽

10.1144/gsjgs.156.3.0633 ◽

1999 ◽

Vol 156 (3) ◽

pp. 633-650 ◽

Cited By ~ 70

Author(s):

P. VAN RENSBERGEN ◽

C. K. MORLEY ◽

D. W. ANG ◽

T. Q. HOAN ◽

N. T. LAM

Keyword(s):

Seismic Data ◽

Structural Evolution ◽

3D Seismic ◽

Brunei Darussalam ◽

Mud Volcanism ◽

3D Seismic Data

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Lithospheric architecture of the Ligurian Basin from seismic travel time tomography

10.5194/egusphere-egu21-2822 ◽

2021 ◽

Author(s):

Anke Dannowski ◽

Heidrun Kopp ◽

Ingo Grevemeyer ◽

Grazia Caielli ◽

Roberto de Franco ◽

...

Keyword(s):

Seismic Data ◽

Velocity Model ◽

P Wave ◽

Central Basin ◽

Uppermost Mantle ◽

Mantle Boundary ◽

Oceanic Spreading ◽

Refraction Seismic ◽

Back Arc ◽

Ligurian Basin

The Ligurian Basin is located north-west of Corsica at the transition from the western Alpine orogen to the Apennine system. The Back-arc basin was generated by the southeast retreat of the Apennines-Calabrian subduction zone. The opening took place from late Oligocene to Miocene. While the extension led to extreme continental thinning little is known about the style of back-arc rifting. Today, seismicity indicates the closure of this back-arc basin. In the basin, earthquake clusters occur in the lower crust and uppermost mantle and are related to re-activated, inverted, normal faults created during rifting.To shed light on the present day crustal and lithospheric architecture of the Ligurian Basin, active seismic data have been recorded on short period ocean bottom seismometers in the framework of SPP2017 4D-MB, the German component of AlpArray. An amphibious refraction seismic profile was shot across the Ligurian Basin in an E-W direction from the Gulf of Lion to Corsica. The profile comprises 35 OBS and three land stations at Corsica to give a complete image of the continental thinning including the necking zone.The majority of the refraction seismic data show mantle phases with offsets up to 70 km. The arrivals of seismic phases were picked and used to generate a 2-D P-wave velocity model. The results show a crust-mantle boundary in the central basin at ~12 km depth below sea surface. The P-wave velocities in the crust reach 6.6 km/s at the base. The uppermost mantle shows velocities >7.8 km/s. The crust-mantle boundary becomes shallower from ~18 km to ~12 km depth within 30 km from Corsica towards the basin centre. The velocity model does not reveal an axial valley as expected for oceanic spreading. Further, it is difficult to interpret the seismic data whether the continental lithosphere was thinned until the mantle was exposed to the seafloor. However, an extremely thinned continental crust indicates a long lasting rifting process that possibly did not initiate oceanic spreading before the opening of the Ligurian Basin stopped. The distribution of earthquakes and their fault plane solutions, projected along our seismic velocity model, is in-line with the counter-clockwise opening of the Ligurian Basin.

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Structural analysis of the Rio Preto fold belt (northwestern Bahia / southern Piauí), a doubly-vergent asymmetric fan developed during the Brasiliano Orogeny

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201420130173 ◽

2014 ◽

Vol 86 (3) ◽

pp. 1101-1113 ◽

Cited By ~ 6

Author(s):

FABRÍCIO A. CAXITO ◽

ALEXANDRE UHLEIN ◽

LUIZ F.G. MORALES ◽

MARCOS EGYDIO-SILVA ◽

JULIO C.D. SANGLARD ◽

...

Keyword(s):

Structural Analysis ◽

Structural Evolution ◽

Shear Zones ◽

Central Compartment ◽

Strike Slip ◽

Fold Belt ◽

Main Structure ◽

The North ◽

Brasiliano Orogeny ◽

Analog Models

The Rio Preto fold belt borders the northwestern São Francisco craton and shows an exquisite kilometric doubly-vergent asymmetric fan structure, of polyphasic structural evolution attributed exclusively to the Brasiliano Orogeny (∼600-540 Ma). The fold belt can be subdivided into three structural compartments: The Northern and Southern compartments showing a general NE-SW trend, separated by the Central Compartment which shows a roughly E-W trend. The change of dip of S2, a tight crenulation foliation which is the main structure of the fold belt, between the three compartments, characterizes the fan structure. The Central Compartment is characterized by sub-vertical mylonitic quartzites, which materialize a system of low-T strike slip shear zones (Malhadinha – Rio Preto Shear Zone) crosscutting the central portion of the fold belt. In comparison to published analog models, we consider that the unique structure of the Rio Preto fold belt was generated by the oblique, dextral-sense interaction between the Cristalândia do Piauí block to the north and the São Francisco craton to the south.

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