Outline of Structural Evolution of the Thaumasian Back-Arc Trap Province of Mars, and Related Rim -Orogenic Arcs: A Speculative Hypothesis Based on Earth Geology

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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Stratigraphic response to structural evolution in a tensional back-arc setting and its exploratory significance: Sunda basin, West Java Sea

10.29118/ipa.1948.77.100 ◽

2018 ◽

Cited By ~ 1

Author(s):

A. Wight

Keyword(s):

Structural Evolution ◽

West Java ◽

Java Sea ◽

Arc Setting ◽

Back Arc

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Deep Slab folding and the deformation of the Persian domain

10.5194/egusphere-egu2020-17835 ◽

2020 ◽

Author(s):

Alexandre Boutoux ◽

Arthur Briaud ◽

Claudio Faccenna ◽

Paolo Ballato ◽

Federico Rossetti ◽

...

Keyword(s):

Numerical Model ◽

Transition Zone ◽

Cross Sections ◽

Structural Evolution ◽

Oceanic Lithosphere ◽

Mantle Transition Zone ◽

Plate Deformation ◽

Flooding Event ◽

Back Arc ◽

Subduction System

<ul><li>To unravel the Neotethys subduction history and the evolution of the slab morphology at depth since the mid-Cretaceous, we produced a synthesis of the main events affecting the Persian domain. This synthesis is focused on the upper and lower plates (i.e. the Persian and the Neotethys ocean, respectively) of the subduction system and is based on the compilation of available structural, geochemical and geochronological data. Overall, this compilation allows exploring the structural evolution of the Persian domain and the Neotethys oceanic lithosphere on map view and along selected cross-sections.</li> <li>Furthermore, we performed a 2D single-sided numerical model where we explored the slab behavior at depth and its influence on upper plate deformation. The model suggests that episodic deformation is driven by the folding slab behavior at the mantle transition zone. We combine our data and numerical model into a conceptual scenario to overcome the complexity of the kinematics of the Neotethys slab since the Early Cretaceous. Our modeling approach shows that back-arcs opening and associated extensional deformation are driven by the roll-back of the folded slab into the mantle transition zone. In contrast, back-arc closure and upper plate shortening are triggered by the roll-over of the folding slab. Finally, we associate the widespread, upper plate, Early Miocene marine flooding event to the Neotethys slab avalanche into the lower mantle.</li> </ul>

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Back-arc rifting in the Izu-Bonin Island Arc: Structural evolution of Hachijo and Aoga Shima Rifts

Island Arc ◽

10.1111/j.1440-1738.1992.tb00054.x ◽

1992 ◽

Vol 1 (1) ◽

pp. 16-31 ◽

Cited By ~ 17

Author(s):

Adam Klaus ◽

Brian Taylor ◽

Gregory F. Moore ◽

Fumitoshi Murakami ◽

Yukinobu Okamura

Keyword(s):

Structural Evolution ◽

Island Arc ◽

Bonin Island ◽

Back Arc

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Neogene-Quaternary magmatic activity and its geodynamic implications in the Central Mediterranean region

Annals of Geophysics ◽

10.4401/ag-3896 ◽

1997 ◽

Vol 40 (3) ◽

Author(s):

G. Serri

Keyword(s):

Middle Miocene ◽

Structural Evolution ◽

Space Distribution ◽

Central Mediterranean ◽

Arc Volcanism ◽

Time Space ◽

Lithospheric Extension ◽

Geodynamic Models ◽

Back Arc ◽

Roman Province

The petrogenesis and time/space distribution of the magmatism associated with the formation of the Northern and Southern Tyrrhenian basins, together with the directions and ages of lithospheric extension and/or spreading north and south of the 410N discontinuity, show that the two arc/back-arc systems have undergone a different structural evolution at least since the middle Miocene (Langhian). The geochemical components involved in the genesis of the heterogeneities of the mantle sources of this magmatism require two separate, compositionally different slabs: 1) an old oceanic (Ionian) lithosphere still seismically active below the Calabrian arc and the Southern Tyrrhenian region; 2) an almost seismically inactive continental (Adriatic) lithosphere which carried large amounts of upper crustal materials within the upper mantle under the NW Roman Province/Tuscan/Northern Tyrrhenian region. The proposed geodynamic models require: 1) for the Northern Tyrrhenian/Northern Apenninic arc/back-arc system, the delamination and foundering of the Adriatic continental lithosphere as a consequence of the continental collision between the Corsica block and the Adriatic continental margin. This delamination process, which is still ongoing, probably started in the early-middle Miocene, but earlier than 15-14 Ma, as indicated by the age and petrogenesis of the first documented magmatic episode (the Sisco lamproite) of the Northern Apennine orogenesis; 2) for the Southern Tyrrhenian/Southern Apenninic-Calabrian arc/back-arc system, the roll-back subduction and back-arc extension driven by gravitational sinking of the Ionian oceanic subducted lithosphere. This process started after the end of the arc volcanism of Sardinia (about 13 Ma) but earlier than the first recorded episode of major rifting (about 9 Ma) in the Southern Tyrrhenian back-arc basin.

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Structural Evolution of the Central Kiruna Area, Northern Norrbotten, Sweden: Implications on the Geologic Setting Generating Iron Oxide-Apatite and Epigenetic Iron and Copper Sulfides

Economic Geology ◽

10.5382/econgeo.4844 ◽

2021 ◽

Vol 116 (8) ◽

pp. 1981-2009

Author(s):

Joel B.H. Andersson ◽

Tobias E. Bauer ◽

Olof Martinsson

Keyword(s):

Iron Oxide ◽

Structural Evolution ◽

Geologic Mapping ◽

Basin Inversion ◽

Copper Sulfides ◽

Structural Framework ◽

Temporal Relationships ◽

Copper Gold ◽

Geologic Setting ◽

Back Arc

Abstract To guide future exploration, this predominantly field based study has investigated the structural evolution of the central Kiruna area, the type locality for iron oxide-apatite deposits that stands for a significant amount of the European iron ore production. Using a combination of geologic mapping focusing on structures and stratigraphy, petrography with focus on microstructures, X-ray computed tomography imaging of sulfide-structure relationships, and structural 2D-forward modeling, a structural framework is provided including spatial-temporal relationships between iron oxide-apatite emplacement, subeconomic Fe and Cu sulfide mineralization, and deformation. These relationships are important to constrain as a guidance for exploration in iron oxide-apatite and iron oxide copper-gold prospective terrains and may help to understand the genesis of these deposit types. Results suggest that the iron oxide-apatite deposits were emplaced in an intracontinental back-arc basin, and they formed precrustal shortening under shallow crustal conditions. Subsequent east-west crustal shortening under greenschist facies metamorphism inverted the basin along steep to moderately steep E-dipping structures, often subparallel with bedding and lithological contacts, with reverse, oblique to dip-slip, east-block-up sense of shears. Fe and Cu sulfides associated with Fe oxides are hosted by structures formed during the basin inversion and are spatially related to the iron oxide-apatite deposits but formed in fundamentally different structural settings and are separated in time. The inverted basin was gently refolded and later affected by hydraulic fracturing, which represent the last recorded deformation-hydrothermal events affecting the crustal architecture of central Kiruna.

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Geologic and Structural Evolution of the NE Lau Basin, Tonga: Morphotectonic Analysis and Classification of Structures Using Shallow Seismicity

Frontiers in Earth Science ◽

10.3389/feart.2021.665185 ◽

2021 ◽

Vol 9 ◽

Author(s):

Melissa O. Anderson ◽

Chantal Norris-Julseth ◽

Kenneth H. Rubin ◽

Karsten Haase ◽

Mark D. Hannington ◽

...

Keyword(s):

Moment Tensor ◽

Plate Boundary ◽

Structural Evolution ◽

Strike Slip ◽

Normal Faults ◽

Geologic Mapping ◽

Centroid Moment Tensor ◽

Lau Basin ◽

Fault Kinematics ◽

Back Arc

The transition from subduction to transform motion along horizontal terminations of trenches is associated with tearing of the subducting slab and strike-slip tectonics in the overriding plate. One prominent example is the northern Tonga subduction zone, where abundant strike-slip faulting in the NE Lau back-arc basin is associated with transform motion along the northern plate boundary and asymmetric slab rollback. Here, we address the fundamental question: how does this subduction-transform motion influence the structural and magmatic evolution of the back-arc region? To answer this, we undertake the first comprehensive study of the geology and geodynamics of this region through analyses of morphotectonics (remote-predictive geologic mapping) and fault kinematics interpreted from ship-based multibeam bathymetry and Centroid-Moment Tensor data. Our results highlight two notable features of the NE Lau Basin: 1) the occurrence of widely distributed off-axis volcanism, in contrast to typical ridge-centered back-arc volcanism, and 2) fault kinematics dominated by shallow-crustal strike slip-faulting (rather than normal faulting) extending over ∼120 km from the transform boundary. The orientations of these strike-slip faults are consistent with reactivation of earlier-formed normal faults in a sinistral megashear zone. Notably, two distinct sets of Riedel megashears are identified, indicating a recent counter-clockwise rotation of part of the stress field in the back-arc region closest to the arc. Importantly, the Riedel structures identified in this study directly control the development of complex volcanic-compositional provinces, which are characterized by variably-oriented spreading centers, off-axis volcanic ridges, extensive lava flows, and point-source rear-arc volcanoes. This study adds to our understanding of the geologic and structural evolution of modern backarc systems, including the association between subduction-transform motions and the siting and style of seafloor volcanism.

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