Deformation partitioning in mountain belts: insights from analogue modelling experiments and the Taiwan collisional orogen

AbstractMany orogens on the planet result from plate convergence involving subduction of a continental margin. The lithosphere is strongly deformed during mountain building involving subduction of a plate composed generally of accreted continental margin units and some fragments of downgoing oceanic crust and mantle. A complex deformation involving strong partitioning of deformation modes and kinematics produces crustal shortening, accompanied by crustal thickening. Partitioning depends on three main factors: (1) rheologic layering of the lithosphere; (2) interaction between tectonics and surface processes; (3) subduction kinematics and 3D geometry of continental margins (oblique convergence, shape of indenters). Here we present an original view and discussion on the impact of deformation partitioning on the structure and evolution of orogens by examining the Taiwan mountain belt as a case study. Major unsolved questions are addressed through geological observations from the Taiwan orogen and insights from analogue models integrating surface processes. Some of these questions include: What is the role played by décollements or weak zones in crustal deformation and what is the impact of structural heterogeneities inherited from the early extensional history of a rifted passive continental margin? What is the relationship between deep underplating, induced uplift and flow of crustal material during erosion (finite strain evolution during wedge growth)? Are syn-convergent normal faults an effect of deformation partitioning and erosion? What is the role of strain partitioning on the location of major seismogenic faults in active mountain belts? What can be learned about the long-term and the present-day evolution of Taiwan?

Download Full-text

Oblique collision and deformation partitioning in the SW Iberian Variscides

Solid Earth ◽

10.5194/se-7-857-2016 ◽

2016 ◽

Vol 7 (3) ◽

pp. 857-872 ◽

Cited By ~ 9

Author(s):

Irene Pérez-Cáceres ◽

José Fernando Simancas ◽

David Martínez Poyatos ◽

Antonio Azor ◽

Francisco González Lodeiro

Keyword(s):

Finite Strain ◽

Lateral Displacement ◽

Point Of View ◽

Variscan Orogeny ◽

Strain Partitioning ◽

Complex Deformation ◽

Oblique Collision ◽

Deformation Partitioning ◽

Oblique Convergence ◽

Deformation Patterns

Abstract. Different transpressional scenarios have been proposed to relate kinematics and complex deformation patterns. We apply the most suitable of them to the Variscan orogeny in SW Iberia, which is characterized by a number of successive left-lateral transpressional structures developed in the Devonian to Carboniferous period. These structures resulted from the oblique convergence between three continental terranes (Central Iberian Zone, Ossa-Morena Zone and South Portuguese Zone), whose amalgamation gave way to both intense shearing at the suture-like contacts and transpressional deformation of the continental pieces in-between, thus showing strain partitioning in space and time. We have quantified the kinematics of the collisional convergence by using the available data on folding, shearing and faulting patterns, as well as tectonic fabrics and finite strain measurements. Given the uncertainties regarding the data and the boundary conditions modeled, our results must be considered as a semi-quantitative approximation to the issue, though very significant from a regional point of view. The total collisional convergence surpasses 1000 km, most of them corresponding to left-lateral displacement parallel to terrane boundaries. The average vector of convergence is oriented E–W (present-day coordinates), thus reasserting the left-lateral oblique collision in SW Iberia, in contrast with the dextral component that prevailed elsewhere in the Variscan orogen. This particular kinematics of SW Iberia is understood in the context of an Avalonian plate salient currently represented by the South Portuguese Zone.

Download Full-text

Oblique collision and deformation partitioning in the SW Iberian Variscides

Solid Earth Discussions ◽

10.5194/sed-7-3773-2015 ◽

2015 ◽

Vol 7 (4) ◽

pp. 3773-3815 ◽

Cited By ~ 2

Author(s):

I. Pérez-Cáceres ◽

J. F. Simancas ◽

D. Martínez Poyatos ◽

A. Azor ◽

F. González Lodeiro

Keyword(s):

Finite Strain ◽

Lateral Displacement ◽

Point Of View ◽

Variscan Orogeny ◽

Strain Partitioning ◽

Complex Deformation ◽

Oblique Collision ◽

Deformation Partitioning ◽

Oblique Convergence ◽

Deformation Patterns

Abstract. Different transpressional scenarios have been proposed to relate kinematics and complex deformation patterns. We apply the most suitable of them to the Variscan orogeny in SW Iberia, which is characterized by a number of successive left-lateral transpressional structures developed at Devonian to Carboniferous times. These structures resulted from the oblique convergence between three continental terranes (Central Iberian Zone, Ossa-Morena Zone and South Portuguese Zone), whose amalgamation gave way to both intense shearing at the suture-like contacts and transpressional deformation of the continental pieces in-between, thus showing strain partitioning in space and time. We have quantified the kinematics of the collisional convergence by using the available data on folding, shearing and faulting patterns, as well as tectonic fabrics and finite strain measurements. Given the uncertainties regarding the data and the boundary conditions modeled, our results must be considered as a semi-quantitative approximation to the issue, though very significant from a regional point of view. The total collisional convergence surpasses 1000 km, most of them corresponding to left-lateral displacement parallel to terrane boundaries. The average vector of convergence is oriented E–W (present-day coordinates), thus reasserting the left-lateral oblique collision in SW Iberia, in contrast with the dextral component that prevailed elsewhere in the Variscan orogen. This particular kinematics of SW Iberia is understood in the context of an Avalonian plate promontory currently represented by the South Portuguese Zone.

Download Full-text

The Role of Surface Processes in Partitioning of Strain and Uplift, St. Elias Orogen, Southern Alaska

Earth Science Research ◽

10.5539/esr.v5n1p76 ◽

2016 ◽

Vol 5 (1) ◽

pp. 76 ◽

Cited By ~ 1

Author(s):

Benjamin Patrick Hooks

Keyword(s):

Three Dimensional ◽

Surface Processes ◽

Fault System ◽

Surface Model ◽

Primary Control ◽

Strain Partitioning ◽

Font Size ◽

The North ◽

Oblique Convergence

<span style="font-size: 10.5pt; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;" lang="EN-US">Three-dimensional thermo-mechanical numerical simulations of the ongoing Yakutat–North America collision are used to identify the role of surface processes in triggering localized rapid uplift, exhumation, and strain observed within the St. Elias orogen of southern Alaska. Thermochronological data reveal localized rapid exhumation associated with the Seward-Malaspina and Hubbard Glaciers within a tectonic corner structure where transpressional motion to the south along the Fairweather Fault system transitions to shortening to the north and west within the active fold-and-thrust belt of the St. Elias orogen. The modeled deformation patterns are characteristic of oblique convergence within a tectonic corner, recording the transition from simple shear to contractional strain within a zone spatially consistent with the highest exhumation rates suggesting the corner geometry is the primary control of strain partitioning.</span><span style="font-size: 10.5pt; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;" lang="EN-US">The relative roles of surface-related processes versus tectonics-related processes in the development of this pattern of deformation were tested with the inclusion of an erosional surface model. The presence of surface processes enhanced the uplift and development of a localized rapid exhumation. When spatially and temporally erosion models are employed, the location of maxima is shifted in response. This indicates that efficient erosion, and resultant deposition and material advection can influence the localization of strain and uplift.</span>

Download Full-text

Magmatic flare-up causes crustal thickening at the transition from subduction to continental collision

Communications Earth & Environment ◽

10.1038/s43247-021-00103-z ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Carlos E. Ganade ◽

Pierre Lanari ◽

Daniela Rubatto ◽

Joerg Hermann ◽

Roberto F. Weinberg ◽

...

Keyword(s):

Production Rate ◽

Continental Margin ◽

Subduction Zones ◽

Continental Collision ◽

Crustal Thickening ◽

Time Intervals ◽

West Gondwana ◽

Continental Arc ◽

Order Of Magnitude

AbstractAbove subduction zones, magma production rate and crustal generation can increase by an order of magnitude during narrow time intervals known as magmatic flare-ups. However, the consequences of these events in the deep arc environment remain poorly understood. Here we use petrological and in-situ zircon dating techniques to investigate the root of a continental arc within the collisional West Gondwana Orogen that is now exposed in the Kabyé Massif, Togo. We show that gabbros intruded 670 million years ago at 20–25 km depth were transformed to eclogites by 620 million years ago at 65–70 km depth. This was coeval with extensive magmatism at 20–40 km depth, indicative of a flare-up event which peaked just prior to the subduction of the continental margin. We propose that increased H2O flux from subduction of serpentinized mantle in the hyper-extended margin of the approaching continent was responsible for the increased magma productivity and crustal thickening.

Download Full-text

Contrasting geomorphic and stratigraphic responses to normal fault development during single and multi-phase rifting

10.31223/x5j03h ◽

2021 ◽

Author(s):

Sofia Pechlivanidou ◽

Anneleen Geurts ◽

Guillaume Duclaux ◽

Robert Gawthorpe ◽

Christos Pennos ◽

...

Keyword(s):

Normal Fault ◽

Sedimentary Facies ◽

Surface Processes ◽

Extension Direction ◽

Multi Phase ◽

Fault Growth ◽

Stratigraphic Evolution ◽

The Impact ◽

Topographic Evolution ◽

Previous Phase

Understanding the impact of tectonics on surface processes and the resultant stratigraphic evolution in multi-phase rifts is challenging, as patterns of erosion and deposition related to older phases of extension are overprinted by the subsequent extensional phases. In this study, we use a one-way coupled numerical modelling approach between a tectonic and a surface processes model to investigate topographic evolution, erosion and basin stratigraphy during single and multi-phase rifting. We compare the results from the single and the multi-phase rift experiments for a 5 Myr period during which they experience equal amounts of extension, but with the multi-phase experiment experiencing fault topography inherited from a previous phase of extension. Our results demonstrate a very dynamic evolution of the drainage network that occurs in response to fault growth and linkage and, to depocentre overfilling and overspilling. However, we observe profound differences between topographic and depocenter development during single and multi-phase rifting with implications for sedimentary facies development. Our quantitative approach, enables us to better understand the impact of changing extension direction on the distribution of sediment source areas and the syn-rift stratigraphic development through time and space.

Download Full-text

The Impact of Surface Processes on the J–V Characteristics of Organic Solar Cells

IEEE Journal of Photovoltaics ◽

10.1109/jphotov.2020.2965401 ◽

2020 ◽

Vol 10 (2) ◽

pp. 514-521

Author(s):

Ali R. Khalf ◽

Jovana P. Gojanovic ◽

Natasa A. Cirovic ◽

Sandra Zivanovic ◽

Petar S. Matavulj

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

Surface Processes ◽

The Impact

Download Full-text

The role of pre-existing weak zones in the formation of the Himalaya and Tibetan plateau: 3-D thermomechanical modelling

Geophysical Journal International ◽

10.1093/gji/ggaa125 ◽

2020 ◽

Vol 221 (3) ◽

pp. 1971-1983

Author(s):

Lin Chen ◽

Lijun Liu ◽

Fabio A Capitanio ◽

Taras V Gerya ◽

Yang Li

Keyword(s):

Tibetan Plateau ◽

Early Stage ◽

Crustal Thickening ◽

The Tibetan Plateau ◽

Crustal Material ◽

Weak Zone ◽

Orogenic Wedge ◽

Orogenic Plateau ◽

Weak Zones

SUMMARY The Tibetan crust is sliced by several east–west trending suture zones. The role of these suture zones in the evolution of the Himalayan range and Tibetan plateau remains unclear. Here we use 3-D thermomechanical simulations to investigate the role of pre-existing weak zones within the Asian Plate in the formation of orogen and plateau growth during continental collision. Our results show that partitioning of deformation along the convergent margin leads to scraping off of crustal material into an orogenic wedge above the margin and crustal thickening in the retro-continent, eventually forming a large orogenic plateau in front of the indenter. Pre-existing weak zone(s) within the retro-continent is reactivated at the early stage of convergence, and facilitates the northward propagation of strain and widening of the orogenic plateau. The northernmost weak zone sets the northern limit of the Tibetan plateau. Our models also show rheological weakening of the congested buoyant crust within the collisional zone drives wedge-type exhumation of deeply buried crust at the southern flank of the plateau, which may explain the formation of the Greater Himalayan Sequence.

Download Full-text

2-way coupling the hydrological land surface model PROMET with the regional climate model MM5

Hydrology and Earth System Sciences ◽

10.5194/hess-17-1705-2013 ◽

2013 ◽

Vol 17 (5) ◽

pp. 1705-1714 ◽

Cited By ~ 21

Author(s):

F. Zabel ◽

W. Mauser

Keyword(s):

Heat Flux ◽

Land Surface ◽

Regional Climate ◽

Surface Processes ◽

Surface Model ◽

Land Surface Processes ◽

Near Surface ◽

Danube Catchment ◽

Simulated Precipitation ◽

The Impact

Abstract. Most land surface hydrological models (LSHMs) consider land surface processes (e.g. soil–plant–atmosphere interactions, lateral water flows, snow and ice) in a spatially detailed manner. The atmosphere is considered as exogenous driver, neglecting feedbacks between the land surface and the atmosphere. On the other hand, regional climate models (RCMs) generally simulate land surface processes through coarse descriptions and spatial scales but include land–atmosphere interactions. What is the impact of the differently applied model physics and spatial resolution of LSHMs on the performance of RCMs? What feedback effects are induced by different land surface models? This study analyses the impact of replacing the land surface module (LSM) within an RCM with a high resolution LSHM. A 2-way coupling approach was applied using the LSHM PROMET (1 × 1 km2) and the atmospheric part of the RCM MM5 (45 × 45 km2). The scaling interface SCALMET is used for down- and upscaling the linear and non-linear fluxes between the model scales. The change in the atmospheric response by MM5 using the LSHM is analysed, and its quality is compared to observations of temperature and precipitation for a 4 yr period from 1996 to 1999 for the Upper Danube catchment. By substituting the Noah-LSM with PROMET, simulated non-bias-corrected near-surface air temperature improves for annual, monthly and daily courses when compared to measurements from 277 meteorological weather stations within the Upper Danube catchment. The mean annual bias was improved from −0.85 to −0.13 K. In particular, the improved afternoon heating from May to September is caused by increased sensible heat flux and decreased latent heat flux as well as more incoming solar radiation in the fully coupled PROMET/MM5 in comparison to the NOAH/MM5 simulation. Triggered by the LSM replacement, precipitation overall is reduced; however simulated precipitation amounts are still of high uncertainty, both spatially and temporally. The distribution of precipitation follows the coarse topography representation in MM5, resulting in a spatial shift of maximum precipitation northwards of the Alps. Consequently, simulation of river runoff inherits precipitation biases from MM5. However, by comparing the water balance, the bias of annual average runoff was improved from 21.2% (NOAH/MM5) to 4.4% (PROMET/MM5) when compared to measurements at the outlet gauge of the Upper Danube watershed in Achleiten.

Download Full-text

Calculating Power Parameters of Rolling Mill Based on Model of Deformation Zone with Four-Roll Passes

Machines ◽

10.3390/machines8040073 ◽

2020 ◽

Vol 8 (4) ◽

pp. 73

Author(s):

Marina N. Samodurova ◽

Olga I. Karandaeva ◽

Vadim R. Khramshin ◽

Ivan V. Liubimov

Keyword(s):

Mathematical Models ◽

Deformation Zone ◽

Rolling Mill ◽

Process Conditions ◽

Complex Deformation ◽

Multivariable Control Systems ◽

Digital Twins ◽

Mill Equipment ◽

Metal Treatment ◽

The Impact

Making “digital twins” for rolling processes and mill equipment should begin with the development of mathematical models of the deformation zone. The deformation zone of two-high flat mill rolling have been studied in detail, relevant models are available in many academic papers. However, the same cannot be said about the most complex deformation zones in stands with multi-roll gauge. Therefore, the task of their reliable mathematical description is of immediate interest. The development of mathematical models is necessary for the design of new wire mills and rolling-drawing units. The combination of rolling in stands with multi-roll gauge and drawing is a promising direction in the production of wire from difficult-to-form steels and alloys. Digital models for pressure-based metal treatment are also necessary for calculating the rolling-mill power parameters during the development of new assortments at the operating mills. The models of deformation zones present the basis for developing the multivariable control systems of process conditions of continuous mills. This research is devoted to the study of the deformation zone and the development of a procedure for calculating the power parameters of rolling in a stand with four-roll passes. The solution of these challenges is given using the example of an operating five-stand wire mill. The authors analysed the known analytical dependencies for calculating the rolling mill force and torque. A mathematical model of the deformation zone and a program for calculating the power parameters have been developed. The paper compares the results obtained from calculations based on analytical dependence and on modelling. A comparison with the experimental parameters obtained at the mill is given. The authors assess the feasibility of using the known formulas and analyse the impact of the front and rear tensions on the power parameters of rolling mill. The problem of developing an automatic tension control system for continuous mills with multi-roll groove is substantiated.

Download Full-text