scholarly journals Influencia de cuerpos discordantes de distinta cohesión en la geometría estructural de fajas plegadas y corridas: aproximación sobre la base de un modelamiento analógico

2021 ◽  
Vol 48 (1) ◽  
pp. 153
Author(s):  
Matías Villarroel ◽  
Pamela Jara ◽  
Reynaldo Charrier
Keyword(s):  
Deformation Pattern ◽  
Structural Pattern ◽  
Deformation Front ◽  
Structural Patterns ◽  
First Case ◽  
Thrust Belts ◽  
Fold And Thrust Belt ◽  
Distal Edge ◽  
Host Rocks ◽  
High Degree

Lithological heterogeneities in a rock series deformed by the development of a fold-and-thrust belt (FTB) affects the pattern of the resulting structures. We present a series of analogue experiments to determine the effect caused on the deformation pattern of a FTB by the presence of cohesive bodies, like plutons or basement blocks that oppose greater resistance than the host rocks to contractional deformation. The influence of these bodies on the deformation pattern of the FTB was studied by incorporating discordant bodies with different cohesions within a stratified granular sequence with negligible cohesion. We describe two sets of experiments in which the inserted body presents low (Co1) and high (Co2) cohesion respectively. The experiments show a tendency of the structural pattern to curve around the inserted body and to migrate towards the deformation front or the foreland, even when the cohesive body is not exposed. In the first case (Co1) the thrusts cut across the cohesive body, while in the second one (Co2) the cohesive body is not faulted, but transferred towards the deformation front along a basal detachment. Comparison of these results with natural examples at different scales shows a high degree of coincidence in the structural patterns recognized in both cases. Two of the main characteristics of these patterns are the tendency of the thrust faults traces to avoid the cohesive body and adopt the geometry of its distal edge. In order to explain curvatures in natural structural patterns in fold-and-thrust belts, we suggest consider the presence of unexposed bodies with higher strength than their environment.

scholarly journals How the presence of a salt décollement in the sedimentary cover influences the behavior of subsalt thrusts in fold-and-thrust belts

2017 ◽  
Vol 188 (6) ◽  
pp. 37 ◽  
Author(s):  
Bruno C. Vendeville ◽  
Tang Pengcheng ◽  
Fabien Graveleau ◽  
Huang Shaoying ◽  
Xin Wang
Keyword(s):  
Sedimentary Cover ◽  
Critical Surface ◽  
Thrust Belt ◽  
Surface Slope ◽  
Deformation Front ◽  
Low Viscosity ◽  
Thrust Belts ◽  
Fold And Thrust Belt ◽  
Analogue Experiments ◽  
Free Domain

We conducted a series of analogue experiments on shortening of a brittle cover (dry sand) above a deep, thin, frictional detachment (glass microbeads). In some experiments, the cover was homogeneous, entirely brittle. In others, there was a thin viscous silicone layer (representing salt) embedded at mid height into the cover, and initially located in the foreland of the fold-and-thrust belt. Our goal was to determine whether or not the presence of such a décollement in the cover could have an impact on the mechanics and kinematics of the underlying subsalt thrusts. Results confirm that, once the front of the foldbelt reached the hinterland salt pinch out, the kinematics of the deeper belt changed drastically: its front stopped propagating forward, and most of the subsequent shortening was accommodated by a larger-than-normal slip along the foremost and youngest deep thrust, while, above the salt décollement, the deformation front propagated very fast, creating a very low surface slope. We hypothesize that it is the gentle sub-critical surface slope associated with rocksalt’s low viscosity that prevents the build-up of an overall surface slope steep enough to allow the underlying, deep foldbelt to continue propagating forward. Finally, one experiment in which only one half of the width of the model comprised an interbedded viscous décollement has shown that the kinematics of the deep thrust was affected even in the adjacent salt-free domain.

scholarly journals CHANGES IN THE MUCOSA OF THE UTERINE POD IN CANCER OF THE VAGINAL PART AND CERVIX

2020 ◽  
Vol 5 (5) ◽  
pp. 410-435
Author(s):  
M. Mironov
Keyword(s):  
Mucous Membrane ◽  
Individual Case ◽  
The Body ◽  
Lymphoid Cells ◽  
Surface Layers ◽  
First Case ◽  
Epitheloid Cells ◽  
Deep Layers ◽  
High Degree ◽  
Sarcomatous Degeneration

Changes in the mucous membrane of the body of the uterus, accompanying cancer of the vaginal part and cervix, drew special attention after the work of Abel (see No. I), which appeared in 1888. The author studied the mucous membrane of the body of the uterus, taken from extirpated cases of 6 uterus for carcinoma portionis and in 1 case for carcinoma cervicis. "In all cases, the mucous membrane is dull," says the author (p. 279, 1. p.), To a high degree of alteration, while the mucous membrane of the cervix is ​​relatively insignificantly diseased. " These changes, as can be seen from the description of each individual case, concern both the gland and the intermediate tissue, and the first in all cases were multiplied and represented corkscrew gyrus; some of them were enlarged or contained ectases of the lateral walls and processes protruding into the lumen of the gland. Changes in the intermediate tissue in cases 1, 2 and 4 consisted in the multiplication of cells in deep layers, and here they had a short-spindle-shaped shape, small size and went in trains in different directions; in the surface layers, they were more or less round, much larger in size and resembled epitheloid cells. In addition, a nested infiltration with small, round cells (lymphoid cells?) Met in places. In the remaining 4 cases, the changes in the intermediate tissue, according to the author's description, were the same as usually in chronic inflammation (cases 5, 6 and 7) or almost absent (case 3). On the basis of these studies, the author comes to the conclusion that changes in the mucous membrane of the body of the uterus in cancer of the vaginal part and cervix have the character of sarcomatous degeneration, which in observed 1, 2 and 4-m, already reached a rather high degree of 4, in the rest, although it did not appear as sharp as especially in the first case, but nevertheless, these changes, according to the author, cannot be considered as inflammatory, but should be taken only as a more weak degree of the same sarcomatous degeneration, by analogy with the first.

Polymerase chain reaction in the diagnosis of parotid gland tuberculosis

1998 ◽  
Vol 112 (5) ◽  
pp. 494-496 ◽  
Author(s):  
Enis Alpin Güneri ◽  
Ahmet Ömer İkiz ◽  
Nese Atabey ◽  
Özlem İzci ◽  
Semih Sütay
Keyword(s):  
Polymerase Chain Reaction ◽  
Differential Diagnosis ◽  
Parotid Gland ◽  
Mycobacterial Infection ◽  
Social Characteristics ◽  
Causative Organism ◽  
Chain Reaction ◽  
First Case ◽  
Polymerase Chain ◽  
High Degree

AbstractA parotid gland mass with presenting features of malignancy is a diagnostic and therapeutic challenge. The histological nature of the lesion must be clearly determined before proceeding with facial nerve sacrificing surgery. Although rare, tuberculosis of the parotid gland must be included in the differential diagnosis of a parotid gland mass especially when the social characteristics of the patient suggests a mycobacterial infection. Primary tuberculosis of the parotid gland is generally encountered among populations with a high incidence of pulmonary disease. The difficulty in the differential diagnosis of a parotid gland malignancy may be helped by a high degree of clinical suspicion, since laboratory tests generally do not identify the specific causative organism. This article reports the first case of parotid gland tuberculosis with clinical and radiodiagnostical features simulating malignancy in which the diagnosis was confirmed by the polymerase chain reaction (PCR).

An Anonymous Email Identification Solution based on Writing Structural Patterns

2015 ◽  
Vol 7 (2) ◽  
pp. 37-49
Author(s):  
Yanhua Liu ◽  
Guolong Chen ◽  
Yiyun Zhang
Keyword(s):  
Decision Making ◽  
Analytic Hierarchy Process ◽  
Digital Forensics ◽  
Frequent Pattern ◽  
Analytic Hierarchy ◽  
Structural Pattern ◽  
Structural Patterns ◽  
Pattern Growth ◽  
Weight Calculation ◽  
Hierarchy Process

A method to analyze anonymous emails in digital forensics is presented in this paper. The frequent pattern-growth algorithm is used in the proposed method to analyze an email and obtain the structural email writing pattern of the user. The influence of a user's writing structural pattern on the analysis of an anonymous email varies. The analytic hierarchy process is used to calculate the weight of a user's different writing structural patterns. For a given anonymous email, matching the writing structural pattern and weight calculation can help investigators improve their decision making and determine the author of an anonymous email in forensic work.

scholarly journals AcanthamoebaSpecies Keratitis in a Soft Contact Lens Wearer Molecularly Linked to Well Water

2006 ◽  
Vol 17 (2) ◽  
pp. 120-122 ◽  
Author(s):  
Samira Mubareka ◽  
Michelle Alfa ◽  
Godfrey K Harding ◽  
Gregory Booton ◽  
Marilyn Ekins ◽  
...  
Keyword(s):  
Contact Lens ◽  
Present Report ◽  
Well Water ◽  
Soft Contact ◽  
Contact Lens Wearer ◽  
Contact Lens Wear ◽  
Soft Contact Lens ◽  
First Case ◽  
Primary Care Practitioners ◽  
High Degree

Acanthamoebaspecies keratitis has been associated with soft contact lens wear. In the present report, an epidemiological link was established between the patient's isolate and well water from the home using molecular methods. To the authors' knowledge, this is the first case in Canada where such a link has been established. Primary care practitioners and specialists, including ophthalmologists and infectious diseases specialists, must maintain a high degree of clinical suspicion in soft contact lens wearers with keratitis unresponsive to conventional topical and systemic treatment.

Anisotropy of magnetic susceptibility as strain indicator in a fold-and-thrust belt sandbox model above décollements with frictional contrast

2020 ◽  
Author(s):  
Thorben Schöfisch ◽  
Hemin Koyi ◽  
Bjarne Almqvist
Keyword(s):  
Magnetic Susceptibility ◽  
Complex Structure ◽  
Anisotropy Of Magnetic Susceptibility ◽  
Magnetic Fabric ◽  
Low Friction ◽  
Thrust Belts ◽  
Fold And Thrust Belt ◽  
Analogue Models ◽  
The Individual ◽  
Strain Indicator

<p>Magnetic fabric is used as strain indicator to provide further insights into different tectonic settings. Applying anisotropy of magnetic susceptibility (AMS) analysis on analogue models has shown to be a useful approach to understand details of deformation. Here we use this technique on shortened sandbox models to illustrate the relationship between rotation of grains and the influence of décollement friction in fold-and-thrust belts. Layers of sand were scraped to a thickness of 2.5 cm on top of high-friction sandpaper on one side and on low-friction fibreglass on the other side of the sandbox model. After shortening the model by 26%, samples were taken at the surface and at depth for measuring AMS. During shortening, above the high-friction décollement, a stack of imbricates was formed, which shows distinct clustering of the main principal magnetic susceptibility axes (k1 ≥ k2 ≥ k3) around the dip of the forethrusts. In contrast, AMS data above the low-friction décollement show a more heterogeneous AMS pattern due to complex structure development with box folds and fault bending. In general, the magnetic fabric can be differentiated between the initial model fabric in the foreland and a tectonic overprint within the hinterland. The AMS analysis show that strain increases with the development of structures towards the hinterland and additionally with depth, but differs between the two frictional décollements. At the transition zone between the two different frictional environments, a deflection zone developed where the trace of thrusts change trend causing additional rotation of sand grains within this zone perpendicular to main shortening direction, as reflected by the orientation of the k1 and k3 axes. Overall, the orientation of the AMS axes and shape of anisotropy depend on the structure geometry and movement, which are determined by the friction of the individual décollement beneath. Consequently, AMS in models indicates and describes the development of structures and reflects strain above different basal friction.</p>

The crustal structure in the transition from the on land fold-and-thrust belt to the offshore accretionary prism in the Taiwan arc-continent collision

2020 ◽  
Author(s):  
Joaquina Alvarez-Marrón ◽  
Dennis Brown ◽  
Juan Alcalde ◽  
Ignacio Marzán ◽  
Hao Kuo-Chen
Keyword(s):  
Continental Margin ◽  
Seismic Tomography ◽  
Accretionary Prism ◽  
Crustal Thickening ◽  
Accretionary Wedge ◽  
Thrust Belt ◽  
Deformation Front ◽  
Coast Line ◽  
Transition Area ◽  
Fold And Thrust Belt

<p>The region of Taiwan is undergoing active, oblique arc-continent colision between the Luzon Arc on the Philippine Sea Plate and the continental margin of Eurasia. The Fold-and-Thrust Belt (FTB) in Taiwan passes southwards into a submarine accretionary wedge at the Manila subduction zone. The aim of this contribution is to examine how an on land FTB changes into a marine accretionary prism in the context of an oblique arc-continent collision. The Miocene pre-orogenic sediments of the continental margin are widespread in the FTB ca. 23° latitude while the offshore wedge is built up dominantly by Pliocene to recent syn-orogenic sediments. In the transition area from the marine accretionary wedge ca. 21° latitude to the on land FTB, the thrust wedge is climbing up the slope of the Eurasian continental margin. The deformation front is at sea floor depth of ca. 4 km in the south to less than 1 km as it reaches the coast line. Here we use the island surface geology, marine reflection seismic profiles, and seismic tomography models to construct contour maps of the basal thrust and the depth to the Moho across a transition area from near 23° to near 21° latitude. In this zone, the deformation front draws a convex curvature as the wedge widens from ca. 50 in the north and south, to more than 130 km near 22° latitude. The basal thrust surface shows a scoop shape as its dip changes from southeast near the coast line to east southward. The basal thrust reaches over 7 km deep beneath the rear of the FTB before ramping into de basement and merging into the Chaochou fault at 10 km depth. Offshore, it shows a gentler dip from 7 km to c. 10 km depth before getting steeper towards the east below the Hengchung Ridge. The basal cuts laterally along-strike through the margin’s sedimentary cover to incorporate thicker Miocene pre-orogenic sediments onto its hanging wall as it passes from the offshore wedge to the on land FTB.</p><p>In the offshore area, the Moho (we use a Vp proxy of 7.5 km/s extracted from the seismic tomography) shallows southeastward, from near 25 km depth below the shelf slope break to less than 17 km depth below the offshore wedge near 21.5° latitude before it starts to deep east towards beneath the Taiwan coast. The Moho dips northeast from near 25 km depth below the coast near Kaohsiung, to near 40 depth below the rear of the FTB at 23.5°, latitude. This complex morphology of the Moho may be related to the changes in crustal thickness and the obliquity of the collision. Because of this, crustal thickening is less pronounced beneath southern Taiwan where the thinner part of the margin is colliding with the arc.</p><p>This research is part of project PGC2018-094227-B-I00 funded by the Spanish Research Agency from the Ministry of Science Innovation and Universities of Spain.</p>

The Barreme Basin and the Gevaudan diapir - an example of the interplay between compressional tectonics and salt diapirism

2020 ◽  
Author(s):  
Rod Graham ◽  
Adam Csicsek
Keyword(s):  
Foreland Basin ◽  
Finite Geometry ◽  
Driving Mechanism ◽  
Salt Diapirism ◽  
Sedimentary Evolution ◽  
Tectonic History ◽  
Thrust Belts ◽  
Fold And Thrust Belt ◽  
History Of

<p><strong>The Barreme Basin and the Gevaudan diapir - an example of the interplay between compressional tectonics and salt diapirism </strong></p><p><strong> </strong></p><p><strong>Adam Csicsek and Rod Graham</strong></p><p>Imperial College London</p><p><strong> </strong></p><p>Our understanding of the role of salt diapirism in determining the finite geometry of fold and thrust belts has grown apace in the last few years, but the interplay between the two remains a significant problem for structural interpretation. The Gevaudan diapir in the fold and thrust belt of the sub-Alpine chain of Haute Provence is well known and has been documented by numerous eminent alpine structural geologists. Graciansky, Dardot, Mascle, Gidon and Lickorish and Ford have all described and illustrated the geometry and evolution of the structure, and Lickorish and Ford’s interpretation is figured as an example of  diapirism  in a compressional setting by Jackson and Hudec in their text on salt tectonics. We review these various interpretations and present another.</p><p>The differences between the various interpretations say much about the complex interplay of salt diapirism and thin-skinned thrusting and have profound implications for the way we interpret the tectonic and sedimentary evolution of the Barreme basin which lies adjacent to the diapir</p><p>The Barreme basin is a thrust-top fragment of the Provencal foreland basin and has been described in detail from both sedimentological (e.g. Evans and Elliott, 1999) and structural (e.g. Antoni and Meckel, 1997) points of view. Here we make the case that it is also a salt related minibasin - a secondary minibasin developed on a now welded allochthonous Middle Cretaceous salt canopy.  We believe that within the basin it is possible to interpret successive depocentres which may record progressive salt withdrawal. We argue that though thrust loading must be the fundamental driving mechanism responsible for salt movement late in the tectonic history of the region, thrusting has not done much more than modify existing salt related geometry.    </p>

scholarly journals Resilience in the Context of the Implementation of the EU-Ukraine Association Agreement

2021 ◽  
pp. 1-26
Author(s):  
Roman Petrov ◽  
Oksana Holovko-Havrysheva
Keyword(s):  
Market Integration ◽  
Internal Market ◽  
Association Agreement ◽  
Trade Dispute ◽  
First Case ◽  
Institutional Cooperation ◽  
Bilateral Cooperation ◽  
High Degree ◽  
Institutional Mechanism ◽  
The Eu

This article examines the extent of the practice of resilience in the process of the implementation of the EU-Ukraine Association Agreement (AA). Also, it analyses the main legislative and institutional tools promoting resilience of Ukraine’s market integration with the EU. Two cases are considered in this study. The first case is the launch of negotiations on the EU-Ukraine Agreement on Conformity and Acceptance of Industrial Products (ACAA). The second case is an EU-Ukraine Trade Dispute on Export Woods Ban. In both cases the EU institutions and Ukraine display a high degree of flexibility to pursue a policy of resilience to achieve a high degree of EU Internal Market rapprochement. In the case of Ukraine, the institutional mechanism of the EU-Ukraine AA remains unused as a forum to discuss effectively and to find solutions for impeding problems in the bilateral cooperation agenda. Therefore, a coherent, transparent, and effective institutional cooperation framework in the bilateral EU-Ukraine relations is still needed.

scholarly journals Control of 3D tectonic inheritance on fold-and-thrust belts: insights from 3D numerical models and application to the Helvetic nappe system

2019 ◽  
Author(s):  
Richard Spitz ◽  
Arthur Bauville ◽  
Jean-Luc Epard ◽  
Boris J. P. Kaus ◽  
Anton A. Popov ◽  
...  
Keyword(s):  
3D Model ◽  
Swiss Alps ◽  
Thrust Belt ◽  
First Order ◽  
Tectonic Inheritance ◽  
Thrust Belts ◽  
Fold And Thrust Belt ◽  
Model Configuration ◽  
Fold And Thrust Belts ◽  
Half Graben

Abstract. Fold-and-thrust belts and associated tectonic nappes are common in orogenic regions. They exhibit a wide variety of geometries and often a considerable along-strike variation. However, the mechanics of fold-and-thrust belt formation and the control of the initial geological configuration on this formation are still incompletely understood. Here, we apply three-dimensional (3D) thermo-mechanical numerical simulations of the shortening of the upper crustal region of a passive margin to investigate the control of 3D laterally variable inherited structures on the fold-and-thrust belt evolution and associated nappe formation. We consider tectonic inheritance by applying an initial model configuration with horst and graben structures having laterally variable geometry and with sedimentary layers having different mechanical strength. We use a visco-plastic rheology with temperature dependent flow laws and a Drucker-Prager yield criterion. The models show the folding, detachment and horizontal displacement of sedimentary units, which resemble structures of fold and thrust nappes. The models further show the stacking of nappes. The detachment of nappe-like structures is controlled by the initial basement and sedimentary layer geometry. Significant horizontal transport is facilitated by weak sedimentary units below these nappes. The initial half-graben geometry has a strong impact on the basement and sediment deformation. Generally, deeper half-grabens generate thicker nappes and stronger deformation of the neighboring horst while shallower half-grabens generate thinner nappes and less deformation in the horst. Horizontally continuous strong sediment layers, which are not restricted to inital graben structures, cause detachment folding and not overthrusting. The amplitude of the detachment folds is controlled by the underlying graben geometry. A mechanically weaker basement favors the formation of fold nappes while stronger basement favors thrust sheets. The applied model configuration is motivated by the application of the 3D model to the Helvetic nappe system of the French-Swiss Alps. Our model is able to reproduce several first-order structural features of this nappe system, namely (i) closure of a half-graben and associated formation of the Morcles and Doldenhorn nappes, (ii) the overthrusting of a nappe resembling the Wildhorn and Glarus nappes and (iii) the formation of a nappe pile resembling the Helvetic nappes resting above the Infrahelvetic complex. Furthermore, the finite strain pattern, temperature distribution and timing of the 3D model is in broad agreement with data from the Helvetic nappe system. Our model, hence, provides a first-order 3D reconstruction of the tectonic evolution of the Helvetic nappe system based on thermo-mechanical deformation processes.

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