The South Tibetan Detachment System: history, advances, definition and future directions

2018 ◽  
Vol 483 (1) ◽  
pp. 377-400 ◽  
Author(s):  
Dawn A. Kellett ◽  
John M. Cottle ◽  
Kyle P. Larson
Keyword(s):  
Tectonic Evolution ◽  
Shear Zones ◽  
Normal Faults ◽  
The South ◽  
Future Directions ◽  
The Past ◽  
Main Fault ◽  
Fault Trace ◽  
Definition Of ◽  
Upper Boundary

AbstractRecognition and subsequent study of the syn-convergent low-angle normal faults and shear zones – the South Tibetan Detachment System (STDS) – that form the upper boundary of the Himalayan mid-crust fundamentally changed views of how the Himalayan orogenic system developed. This paper reviews the past four decades of discovery and major advances in our understanding of the detachment system. Significantly conflicting maps of the fault trace, as well as proposed extensions of the detachment system up to hundreds of kilometres both up and down dip of the main fault trace, call for a unifying definition of the detachment system based on structural criteria. The different proposed models for the formation of the STDS during tectonic evolution of the Himalayan orogen are compared. Finally, critical outstanding questions about the origin, extent and character of the detachment system are identified and point to future directions for research.

scholarly journals Geophysical characterisation of two segments of the Møre-Trøndelag Fault Complex, Mid-Norway

2011 ◽  
Vol 3 (1) ◽  
pp. 159-186
Author(s):  
A. Nasuti ◽  
C. Pascal ◽  
J. Ebbing ◽  
J. F. Tønnesen
Keyword(s):  
Tectonic Evolution ◽  
Deep Structure ◽  
Normal Fault ◽  
Geophysical Data ◽  
Data Sets ◽  
Normal Faulting ◽  
The South ◽  
The Past ◽  
Magnetic Resistivity ◽  
Wide Zone

Abstract. The Møre-Trøndelag Fault Complex (MTFC) has controlled the tectonic evolution of Mid-Norway and its shelf for the past 400 Myr through repeated reactivations during Paleozoic, Mesozoic and perhaps Cenozoic times, the very last phase of reactivation involving normal to oblique slip faulting. Despite its pronounced signature in the landscape, its deep structure has remained unresolved until now. We focused on two specific segments of the MTFC (i.e. the so-called "Tjellefonna" and "Bæverdalen" faults) and acquired multiple geophysical data sets (i.e. gravity, magnetic, resistivity and shallow refraction profiles). A 100–200 m wide zone of gouge and/or brecciated bedrock dipping steeply to the south is interpreted as being the "Tjellefonna Fault" stricto sensu. The fault appears to be flanked by two additional but minor damage zones. A secondary normal fault also steeply dipping to the south but involving indurated breccias was detected ~1 km farther north. The "Bæverdalen Fault" is interpreted as a ~700 m wide and highly deformed zone involving fault gouge, breccias and lenses of intact bedrock, as such it is probably the most important fault segment in the studied area and accommodated most of the strain during presumably late Jurassic normal faulting. Our geophysical data are indicative of a "Bæverdalen Fault" dipping steeply towards the south, in agreement with the average orientation of the local tectonic grain. Our findings suggest that the influence of Mesozoic normal faulting along the MTFC on landscape development is more complex than previously anticipated.

scholarly journals Early Permian Paleomagnetic Result from the South Beishan (NW China) and Its Implications for the Tectonic Evolution of the SW Central Asian Orogenic Belt

2020 ◽  
Author(s):  
Xin Zhu ◽  
Yan Chen ◽  
Bo Wang ◽  
Stéphane Scaillet ◽  
Michel Faure ◽  
...  
Keyword(s):  
Tectonic Evolution ◽  
Shear Zones ◽  
Orogenic Belt ◽  
Central Asian Orogenic Belt ◽  
Early Permian ◽  
The South ◽  
Dike Swarm ◽  
Closure Time ◽  
Central Asian ◽  
Final Closure

<p><span>The Beishan Orogenic Belt plays an important role in understanding the Paleozoic tectonic evolution of the Central Asian Orogenic Belt and the final closure time of the Paleo-Asian Ocean. However, although numerous geochronologic, geochemical, and isotopic data have been</span> <span>obtained,</span><span> no consensus has been reached yet on the Early Permian tectonic setting for this region and, thus, the final closure time of the Paleo-Asian Ocean, mainly because of the nonuniqueness of the interpretations deduced from such data base. Therefore, other methods are urgently needed to provide more constraints from different perspectives. We present here a paleomagnetic study on the Gubaoquan doleritic dike swarm in the South Beishan area. Thermo-magnetic experiments and room-temperature hysteresis loops reveal that single-domain and multi-domain magnetite is the principal carrier of remanence. Anisotropy of magnetic susceptibility of studied dikes shows a horizontal magnetic foliation with a magnetic lineation generally parallel to the dikes’ strike. Plagioclase <sup>40</sup>Ar/<sup>39</sup>Ar dating result of one dolerite sample collected from the margin of a 10m-thick dike provides a cooling age at 300~284 Ma. Scanning electronic microscope observation coupled with energy-dispersive X-ray spectrometry shows that the remanence carrier is mainly euhedral without evident chemical alteration nor secondary mineral formation. Characteristic remanent magnetizations are successfully isolated from twenty dikes, and pass baked contact test. According to <em>Deenen et al. </em>(2011) statistical criteria, the distribution of the remanence directions reflects the contribution from paleosecular variation of the geomagnetic field. Taking all data together, the Gubaoquan doleritic dike swarm probably preserves a primary remanence. Consequently, an Early Permian paleomagnetic pole for the South Beishan can be calculated at <em>λ</em> = 80.2°N, <em>φ</em> = 300.3°E, <em>A<sub>95</sub></em> = 5.3° and <em>N</em> = 20. Comparisons of this new result with published ones from neighboring blocks bring us following implications for the tectonic evolution of the SW CAOB: 1. Neither relative latitudinal movement nor relative rotation can be paleomagnetically detected among Yili, Turpan-Hami, and South Beishan since the Early Permian. 2. Significant relative rotations have taken place between South Junggar and Tarim with respect to South Beishan-Turpan-Hami-Yili, respectively, since the Early Permian, corresponding to large-magnitude strike-slip displacements along mega-shear zones. 3. No obvious relative latitudinal movement has occurred between South Beishan and its neighboring blocks (Tarim, South Junggar, Yili, Turpan-Hami, and Dunhuang) since the Early Permian, combined with other evident, suggesting that the Paleo-Asian Ocean probably have closed before the Early Permian, and South Beishan was in a rift setting in the Early Permian.</span></p>

Inversion of argon data implies extreme extension in and below the orogenic lid of the European Alps during Eocene–Oligocene collision

2021 ◽  
Author(s):  
Gordon Lister ◽  
Marnie Forster ◽  
Jack Muston ◽  
Jason Price ◽  
Gianreto Manatschal
Keyword(s):  
High Vacuum ◽  
Temperature Drop ◽  
Shear Zones ◽  
Potassium Feldspar ◽  
Ultra High Vacuum ◽  
Normal Faults ◽  
European Alps ◽  
Diffusion Parameters ◽  
Extreme Extension ◽  
Definition Of

<p>Here we demonstrate conjoint inversion of data combined from <sup>40</sup>Ar/<sup>39</sup>Ar geochronology and ultra-high-vacuum (UHV) <sup>39</sup>Ar diffusion experiments using potassium feldspar. The method allows precise definition of diffusion parameters for a collection of domains, using an approximation to a fractal geometry. Using the MacArgon program, we could constrain possible temperature histories followed by individual mineral grains in and below the orogenic lid of the European Alps, during its history of mountain building. Tests of the sensitivity of the obtained fits provides insight into the possible range of allowed temperature-time (T-t) paths, and recognition of ‘events’ during which microstructural modification may have taken place. The results suggest a sequence of abrupt cooling events, which could reflect, either: i) cycles of crustal shortening followed by detachment faulting; or ii) initial terrane-stacking beneath the orogenic lid followed by repeated rapid crustal stretching events, each event involving upward stepping of the active detachment fault. Substantial movement on low-angle normal faults and shear zones has taken place, consistent with extreme extension of the mountain belt at high-angles to the convergence direction, in front of the advancing Adriatic indentor. The magnitude of the temperature drop implies that a rapid extension event took place at the time of the Eocene—Oligocene transition, and reduced the thickness of the orogenic lid to a few kilometres.</p>

Value analysis—the technique: State of the art and future directions

2000 ◽  
Vol 214 (4) ◽  
pp. 301-312 ◽  
Author(s):  
G R Kermode ◽  
S Sivaloganathan ◽  
T M M Shahin
Keyword(s):  
State Of The Art ◽  
Function Analysis ◽  
Minimum Cost ◽  
Future Directions ◽  
Value Analysis ◽  
Step Process ◽  
The Past ◽  
Definition Of ◽  
And Function ◽  
Established Technique

Value analysis is an established technique that aims to identify, quantify and rectify weaknesses in products and processes by providing a set of functions at minimum cost. An eight-step process called the ‘job plan’ implements the theory. ‘Value methods’ are widely applied and have evolved with the changing competitive environment over the past 50 years. The definition of value and function analysis are two concepts around which original value analysis was built. This paper assesses the state of the art in value analysis in the context of modern product development. The findings from this analysis are then extrapolated to identify future enhancements to this already powerful technique.

scholarly journals The Invisible Population of Students With Learning Disabilities in South Korea

2021 ◽  
pp. 105345122110148
Author(s):  
Mikyung Shin ◽  
Nari Choi
Keyword(s):  
Special Education ◽  
Learning Disabilities ◽  
South Korea ◽  
Students With Learning Disabilities ◽  
Ongoing Debate ◽  
Future Directions ◽  
The Past ◽  
Definition Of ◽  
Education Support ◽  
The Invisible

Over the past decade, there has been a rapidly declining trend in the prevalence of students with learning disabilities in South Korea. In 2019, only 1.5% of students receiving special education support were identified as having learning disabilities. This column reports on three current issues related to learning disabilities to provide a greater understanding of this declining trend in South Korea: (a) the ongoing debate on the definition of students with learning disabilities, (b) the continuing disagreement on the identification criteria for students with learning disabilities, and (c) the public’s limited understanding of learning disabilities. Suggestions for future directions are also discussed.

scholarly journals A Traditional Communication of Bugis (Note 1) in the South Sulawesi of Indonesia through the Art Performance of Kecapi

2017 ◽  
Vol 13 (3) ◽  
pp. 21
Author(s):  
Muslimin M.
Keyword(s):  
Folk Art ◽  
The South ◽  
Traditional Media ◽  
The Past ◽  
Indonesian Archipelago ◽  
South Sulawesi ◽  
Art Performance ◽  
The Government ◽  
Definition Of

Discussing about traditional communication, it is commonly connected to the tradition concept, which contains a meaning that the concept is a kind of the past finding, but it is commonly reputed as a normative thing by each part of the society. Based on the explanation, it can be concluded that the definition of traditional communication is commonly connected to the folk art performance as a traditional media that is owned by a certain society, as the result it can be identified and understood that a folk art performance is owned by that society and exist as a local wisdom for the society.Therefore, it can be cleared that discussing about traditional communication is cannot be separated with the traditional folk art performance as a media, a kind of art that is based on the folk story by using media that appears and develops in a certain society. The effort of source finding of this folk story is not only purposed to be performed in the form of art performance, but also it is further expected to carry out messages from the story. Therefore, in the review of traditional communication it is emphasized to the way of carrying the messages that are contained in an art performance as a media. Therefore, this review is not discussed about the art performance furtherly. It means that the performance can use a great and luxurious background, but also can be in a simple form.South Sulawesi as a former government of the Indonesian Archipelago (the government of Gowa-Tallo and other governments that had been exist in Indonesia) has various kinds of art performance of the traditional media which are still heired for generations, where the function of traditional media is not only as an entertaining public show, but also may be a guidance because of the role of art performance which is full of messages and senses.Therefore, people who will have an art performance are commonly have to prepare their physic, mental, and psychology, moreover in fact that they will face most of audiences and have an all night (Note 2) performance. So that, in the South Sulawasi, may be in other places, before playing the role as a persistent player in an art performance, the players are commonly practice hard their skill and ability. This ability is usually completed by a mysthical thinking through the magic words or Parimbolo (Bugis’ language). In order to learn the magic words, the players commonly meet the elders, but the magic words are not directly given, but rather have to pass some rituals within certain rules such as white cloth, a cock, or by preparing black sticky rice and black cock (Ajeip Padindang in Monoharto, 2003: ix-x).

scholarly journals Sexuality, gender and culturally diverse interpretations of cyberbullying

2021 ◽  
pp. 146144482110553
Author(s):  
Veronica Sheanoda ◽  
Kay Bussey ◽  
Tiffany Jones
Keyword(s):  
Structured Interviews ◽  
Future Directions ◽  
Youth Groups ◽  
The Public ◽  
The Past ◽  
Gender Diverse ◽  
Sexuality And Gender ◽  
And Gender ◽  
Definition Of ◽  
Diverse Youth

The cyberbullying field has quickly expanded in the past 20 years and especially includes strong emphases on diverse and marginal youth groups. However, the field’s literature defines cyberbullying in widely diverging ways while lacking consideration of how diverse youth groups themselves define and apply the term cyberbullying. This article aimed to consider how culturally, sexuality and gender-diverse youth understandings, experiences and interpretations of cyberbullying can be used to redress gaps in current academic notions of cyberbullying. Semi-structured interviews were conducted with 19 young people exploring their understandings, interpretations and experiences of cyberbullying. Participants were aged 18–25 years and self-identified as from a culturally and linguistically diverse (CALD) background and/or part of the LGBTQIA+ community. Interview question themes explored participants’ social media engagement, online communities and cyberbullying experiences. NVivo was used to perform thematic analyses. Findings largely suggested that the confusion regarding the term and definition of cyberbullying among researchers is also reflected in the population of diverse young people’s understandings and interpretations of cyberbullying. Whether these conflicted definitions were due to the confusion among youth populations or because academics and policymakers have failed to communicate a clear cyberbullying definition to the public was unclear. Considerations and future directions around the language and behaviours that should be included in a definition of cyberbullying are suggested to more clearly communicate the concept to future respondents and to the wider community.

scholarly journals TECTONIC EVOLUTION OF THE BETIC CORDILLERA: AN OVERVIEW

2004 ◽  
Vol 36 (4) ◽  
pp. 1598 ◽  
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.

scholarly journals 3D density modelling of Gemeric granites of the Western Carpathians

2017 ◽  
Vol 68 (3) ◽  
pp. 177-192 ◽  
Author(s):  
Ján Šefara ◽  
Miroslav Bielik ◽  
Jozef Vozár ◽  
Martin Katona ◽  
Viktória Szalaiová ◽  
...  
Keyword(s):  
Tectonic Evolution ◽  
Lower Boundary ◽  
Western Carpathians ◽  
Mountain Range ◽  
The South ◽  
Geophysical Research ◽  
The North ◽  
Basement Rocks ◽  
Tectonic Contact ◽  
Upper Boundary

Abstract The position of the Gemeric Superunit within the Western Carpathians is unique due to the occurrence of the Lower Palaeozoic basement rocks together with the autochthonous Upper Palaeozoic cover. The Gemeric granites play one of the most important roles in the framework of the tectonic evolution of this mountain range. They can be observed in several small intrusions outcropping in the western and south-eastern parts of the Gemeric Superunit. Moreover, these granites are particularly interesting in terms of their mineralogy, petrology and ages. The comprehensive geological and geophysical research of the Gemeric granites can help us to better understand structures and tectonic evolution of the Western Carpathians. Therefore, a new and original 3D density model of the Gemeric granites was created by using the interactive geophysical program IGMAS. The results show clearly that the Gemeric granites represent the most significant upper crustal anomalous low-density body in the structure of the Gemeric Superunit. Their average thickness varies in the range of 5–8 km. The upper boundary of the Gemeric granites is much more rugged in comparison with the lower boundary. There are areas, where the granite body outcrops and/or is very close to the surface and places in which its upper boundary is deeper (on average 1 km in the north and 4–5 km in the south). While the depth of the lower boundary varies from 5–7 km in the north to 9–10 km in the south. The northern boundary of the Gemeric granites along the tectonic contact with the Rakovec and Klátov Groups (North Gemeric Units) was interpreted as very steep (almost vertical). The results of the 3D modelling show that the whole structure of the Gemeric Unit, not only the Gemeric granite itself, has an Alpine north-vergent nappe structure. Also, the model suggests that the Silicicum–Turnaicum and Meliaticum nappe units have been overthrusted onto the Golčatov Group.

Medical Social Work Development in Shanghai

2016 ◽  
Author(s):  
QingYing Ji ◽  
Anao Zhang
Keyword(s):  
Social Work ◽  
Lessons Learned ◽  
Future Directions ◽  
National Policies ◽  
Policy Perspective ◽  
Medical Social Work ◽  
The Past ◽  
Three Stages ◽  
Definition Of ◽  
Further Development

This article offers an overview of medical social work development in Shanghai, China. The Chinese definition of medical social work is introduced, and its development in Shanghai is described. Both from a history and policy perspective, this article outlines the three stages of medical social work development in Shanghai chronologically while introducing relevant national policies for medical social work at each stage. Lessons learned from the past are summarized and reviewed. Finally, future directions for further development are discussed.

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