List of Articles چین‌خوردگی

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  1 - Non-coaxial deformation in sphalerite strain fringe: A kinematic shear indicator in overturned limb of a hanging wall fold
  علي  Nakini علي  Yarmohammadi
  20.1001.1.17357128.1394.9.34.3.7
  Kinematic evidence of shear deformation in strain fringes of sphalerite mineral in an overturned limb of a fold structure are studied. Structural observation in Cretaceous rocks of Tiran Mine Area in west Esfahan, reveals a shear deformation in overturned limb of More

  Kinematic evidence of shear deformation in strain fringes of sphalerite mineral in an overturned limb of a fold structure are studied. Structural observation in Cretaceous rocks of Tiran Mine Area in west Esfahan, reveals a shear deformation in overturned limb of a hanging-wall anticline that has generated with reverse fault in the area. Orientation of strain fibers and their rotations in strain fringes of sphalerite minerals are used for determination of stress orientations and its changes during shear deformation process. This fabric indicates kinematic evolution of the overturned limb of a hanging-wall anticline and related reverse fault during folding. In this study, amount of stretching in strain fringes and their rotation are measured by object-centre path model. Manuscript profile
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  2 - The effect of the Gachsaran mobile formation on folding style and tectonic evolution of the Rag-e- Sefid anticline in the southern Dezful Embayment
  Mehdi Yosefi Seyd Morteza Moussavi Mohammad Mahdi Khatib
  Plastic behavior and significant thickness of the Gachsaran incompetence formation on top of middle carbonate units in the sedimentary sequence of the southern Dezful Embayment led to the emergence of different styles of folding above and below of this formation. So tha More

  Plastic behavior and significant thickness of the Gachsaran incompetence formation on top of middle carbonate units in the sedimentary sequence of the southern Dezful Embayment led to the emergence of different styles of folding above and below of this formation. So that the structures in the upper and lower parts of this formation are completely separated and do not match each other. In the upper anticlines, above the Gachsaran horizon, the calculation of the limbs angle, the main thrust slope and the percentage of forelimb thickening indicate the fault detachment fold style. This style marks the geometry of fold at the early stage of the development of this anticline. Also the seismic profiles below the Gachsaran horizon also show the fault-propagation folding style. In the south Dezful Embayment, folding in the Gachsaran Formation occurs with shorter wavelengths in the form of disharmonic folds. This folding acts as the decoupling surface for the lower folds so that the synclines in this moving horizon directly cover the lower anticlines. The rounded folds in the carbonates in lower anticline are the imposed folds associated with steepened up reverse faults, detached on the basal decollement level and ultimately faulted by progressive deformation. The interpretation of seismic sections in the southern Dezful Embayment shows that lateral migration occurs in the salt units of the GS2 and GS4, and the upper and lower units of the Gachsaran Formation do not play a role in salt migration. Lateral migration in Miocene salts of the Gachsaran Formation is accomplished by the growth of sub-anticline during folding and loading of upper formation at the upper Gachsaran Formation. Manuscript profile
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  3 - Determining paleo-stress based on the study of discontinuities and folds in Zagros Collision Zone; Case Study: Kermanshah Region
  سپیده  رضابیک عبدالله  سعیدی Mehran Aryan علی  سربی
  20.1001.1.17357128.1400.15.57.5.7
  The studied zone is in the Northern part of Zagros Suture Zone (Kermanshah). The presence of deep sea sediments, oceanic crust remnants, platform carbonates, igneous and metamorphosed rocks of active margin and carbonate sequence of passive margin that are assembled in More

  The studied zone is in the Northern part of Zagros Suture Zone (Kermanshah). The presence of deep sea sediments, oceanic crust remnants, platform carbonates, igneous and metamorphosed rocks of active margin and carbonate sequence of passive margin that are assembled in the studied area show a compressional tectonic regime from the late Cretaceous up to the present. As a result of convergent regime, a very complicated structural zone is developed. The main purpose of this study is stress characteristic analysis in Zagros Suture Zone (Kermanshah).To recognize and study the arrangement of stress axes a great amount of data were gathered from the folds axial surface and the faults which are appeared within the rocks specially the radiolaritic rocks. The data includes characteristics of fault surface geometry, fault slip and lineation slip. The stress recording patterns for data in this study is Multiple Inverse Method and comparison with stress position by using folds axial surface. By studying folds it was obtained the situation of main stress σ1, σ2 and σ3 respectively as 029, 127, 234 and by using the method Multiple Inverse Method, the situation of main stress is obtained as 059, 304, 194. Based on the investigations in the study area and measurements on Cretaceous rocks, the results show that the main stress direction since Cretaceous up to the present is northeastern with minor changes. The estimations of stress direction were the same in both folds and faults. As a result, the shortening direction has been constant, so the shortening faults all show one direction of stress. Manuscript profile
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  4 - Investigation of structural pattern and introduction of detachment surface of Alborz Mountain Range in the north of Damghan
  Z. Taslimi A. Saidi M. Ghoreshi M. Aryan A. Solgi
  20.1001.1.17357128.1401.16.61.6.3
  The studied area is a part of Eastern central Alborz, bestween southeastern piedmont of Alborz (NW of Damghan) and North Alborz Fault (South of Sari). The Alborz Mountain range which forms the heights of northern territory, separated the Caspian Depression from Iran cen More

  The studied area is a part of Eastern central Alborz, bestween southeastern piedmont of Alborz (NW of Damghan) and North Alborz Fault (South of Sari). The Alborz Mountain range which forms the heights of northern territory, separated the Caspian Depression from Iran central plateau. The Alborz is one of the Iranian mountain ranges that were deformed during two Cimmerian and Alpine organic events. This deformation is continued until the present day. This research is based on the satellite images, field investigations, drawing structural sections, stratigraphic sequences from the folded and thrusted parts of Alborz Mountains. The studied area is composed of numerous anticlines and synclines from South to North as Tuyeh- Darvar anticline, Sabour anticline, Talma- Darreh anticline, Alikhani syncline, Tarkan anticline, Babr cheshmeh syncline and anticline. Some of these folds are related to faulting which occured due to the typical continuous shortening and faulting of Alborz crust and destroyed their original patterns. The function of main faults and specially thrust faults played an essential role on the present models of mentioned folds. Regarding the axes of the folds, the effective compression over the area has a North, North Waste-South, South-East direction. This direction is perpendicular to axial trend of folds. The physico-mechanical properties of Alborz geological units caused development of detachment surfaces on main faults. The shortening intensity and large displacements have led to disappearance of a limb or whole fold. In this study the three surfaces of detachment were introduced inside the stratigraphic sequences from Precambrian to middle Eocene based on the well-known and documented data. Manuscript profile
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  5 - Investigating the geometry and mechanism of folding in Sulabder anticline (SW Iran)
  Mehdi Yosefi F. Esfahani Seyd Morteza Moussavi
  Calculating the amount of shortening, the angle between ridges, the slope of the main thrust and the percentage of thinning of the front ridge compared to the back ridge in the middle and northwestern parts of Sulabder anticline shows the folding style related to fault More

  Calculating the amount of shortening, the angle between ridges, the slope of the main thrust and the percentage of thinning of the front ridge compared to the back ridge in the middle and northwestern parts of Sulabder anticline shows the folding style related to fault propagation in these parts. The calculation of these geometrical parameters in the south-eastern part of the Sulabder anticline also shows the faulted detachment folding style. The change of folding class from 1c to 2 and 3, as well as the change of fold style from detachment folds to fault propagation style, are a sign of increased shortening, deformation progress and evolution of folding from the south-eastern part. This represents that in the initial stage the thrust fault system belongs to the middle and north-western parts, which are in the developed stages of the thrust fault system. The interpretation of seismic sections perpendicular to the Sulabder anticline in different sections shows that the Sulabder anticline in a raised wedge form is higher than the adjacent structures due to the action of the thrust faults on the northern and southern edges. In the Solabdar anticline, the performance and mobile behavior of marl-shale units of Pabdeh and Gurpi formations, due to its high thickness and formable rheology as an intermediate separation horizon, create different folding styles at the top and bottom of this unit. It also caused displacement in the axis of the upper and deeper parts of anticlines. Manuscript profile