List of Articles Fracture

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  1 - The relationships between diagensis, fracture, distribution of matrix porosity, and well productivities in Bangestan reservoir of Ahwaz field
  Mehdi Khoshnoodkia محمد حسين  آدابي Mahboubeh Hooseni-barzi Mehdi Khoshnoodkia
  Ahwaz Bangestan reservoir (Ilam and Sarvak formations with approximately 1000 meter thickness) were deposited in the Upper Cretaceous period, which is deposited in different sedimentological and tectonic situations. Ahwaz Bangestan reservoir is divided into four reservo More

  Ahwaz Bangestan reservoir (Ilam and Sarvak formations with approximately 1000 meter thickness) were deposited in the Upper Cretaceous period, which is deposited in different sedimentological and tectonic situations. Ahwaz Bangestan reservoir is divided into four reservoir zones (C-E-G-I) which are separated by zones of dense limestone (A-B-D-F-H). This reservoir is formed due to repeating shallowing upward of shoal-bar to lagoonal facies with distribution of rudist debris, with the exception of younger sequence which belongs to deeper environment. Back shoal facies show frequent depositional changes in vertical and horizontal directions in zones C3-E-F-G-I, the changes which can be seen in reservoir. Furthermore, the effect of basement faults, with trend nearly N-S in Ahwaz Bangestan reservoir, resulted in changes of ancient paleogeography. These changes had an important effect on diagentic changes, depositional setting, and finally productivity in conventional and carbonate fractured reservoirs. Matrix porosity is fabric selective in zones C3-E-G-and I. So, grainstone, and packstone facies have better reservoir quality than wackestone and mudstone facies. Diagensis and meteoric waters affected the top of every exposure cycles, and caused the best reservoir quality in grainstone, and packstone facies and productivity of wells. But, zone C1 of Ahwaz Bangestan reservoir (chalky limestone) experienced dominantly solution and leaching, which caused an increase in matrix porosity, but little changes in permeability. Furthermore, the open fractures developed in zones E, F and G which are located in the central and southern parts of the field. Existence of open fractures are confirmed by mud losses, analysis of sedimentary structure and dynamic reservoir data. Increase of mud losses in some area of limestone zones (D, F, and H) could be an indication of vertical relationship of two reservoirs and absence of sedimentological barrier in these areas. Manuscript profile
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  2 - Wellbore Stability Analysis During Drilling Using Geomechanical Model and FLAC3D Software in Asmari Reservoir, Ahwaz Oil Field
  Mohammad میرانی
  Abstract Oil reservoirs are one of the important sources of energy due to which is caused by specific rock mechanical properties, the ability to maintain hydrocarbon fluids. One of the major problems that are occurred during drilling a well is instability of the well More

  Abstract Oil reservoirs are one of the important sources of energy due to which is caused by specific rock mechanical properties, the ability to maintain hydrocarbon fluids. One of the major problems that are occurred during drilling a well is instability of the wellbore. In order to prevent this difficulty its need to predict stability of the rocks by using geomechanical properties and in-situ stresses. A lack of accurate wellbore stability analysis brings many problems such as borehole washout, breakout, collapse, stuck pipes and drill bits. In the present research work the stability of an oil well located in Asmari reservoir of Ahwaz oil field was stimulated by using numerical software FLAC3D and information obtained from well log curves were evaluated and analyzed in two parts and the results were presented. Mud pressure and mud weight in outset of wellbore plastic flow and also outset of shear failure in wellbore were obtained for 7.5 meter of formation which mainly consists of limestone, marl. Well stability analysis was performed in vertical direction, minimum horizontal stress and maximum horizontal stress. Due to plastic movement and shear failure in wellbore, in first stage the mud pressure occurred is 33 and 26.4 Mpa and the second stage it reaches to 45 and 30 Mpa, respectively.It indicates that tensile failure is in direction of maximum horizontal stress and shear failure in direction of minimum horizontal stress. Subsequently, the result shows that the analysis due to the low mechanical properties of the sandstone layer indicates the maximum amount of displacement and loss. The safe mud window is small in this layer. Manuscript profile
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  3 - Numerical calculation of permeability tensor in fractured reservoirs
  سیما جلیلی رئوف حسین معماریان محمد رضا  رسائی بهزاد تخم چی
  Abstract Proper characterization of fracture reservoir is crucial for their sound development plan. It is however very difficult to correctly obtain various fracture reservoir properties such as permeability due to high order of heterogeneity and anisotropy within th More

  Abstract Proper characterization of fracture reservoir is crucial for their sound development plan. It is however very difficult to correctly obtain various fracture reservoir properties such as permeability due to high order of heterogeneity and anisotropy within these reservoirs. Classical dual porosity and/or dual permeability models consider a regular fracture network across the reservoir. To improve the concept, we develop a numerical method for tonsorial permeability calculation of blocks with random/disordered fracture distribution. We considered a 2D Cartesian fine grid in which the fractures were defined explicitly with their endpoints coordinates. Applying proper boundary conditions, single phase flow is then solved. Full tensor permeability is then obtained analytically from the calculated flow and pressure fields. The result of our method is compared well with that of the analytical models for simple fracture systems. In addition we reported the permeability tensor values of random fracture networks where no analytical solution is available. Manuscript profile
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  4 - Fractures systematic analysis Asmari reservoir Formation in the Marun oil field (based on image logs interpretation results)
  فارسی مدان arsimadan
  In the oil buildings to investigate fractures in the reservoir rock fractures in stages of production and field development is very important and necessary. Now application of software repository in the realization of this issue will help to petroleum with the geologist More

  In the oil buildings to investigate fractures in the reservoir rock fractures in stages of production and field development is very important and necessary. Now application of software repository in the realization of this issue will help to petroleum with the geologists.. Marun oil field is one of the largest oil fields in the South West Iran of the city of Ahvaz in the Northeast and the North embayment Dezful of geology in the eastern. Marun field is the most important Asmari reservoir. The aim of this study was to investigate systematically Asmari reservoir fractures and the development of fractures in the reservoir. For this purpose, using image logs, best and most complete method interpretation and results of 11 wells in fracture studying and 16 wells in in-situ stress direction studying. According to frequency of fractures (based on image logs interpretation results) in the southern and north-eastern limb of the field, The theory of tectonic folding and bending events later caused the possible activities during the north-south strike-slip faults affect the compression force has been created to strengthen. Most of image logs data in Marun field are fractures with extensions; N155E, N130E, N95E, N60E, N30E. Manuscript profile
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  5 - Fracture analysis of the Asmari Formation of Dara anticline, as analog model for other Asmari subsurface hydrocarbon reservoirs
  saeed mohammadi asl Ali Farzipour Saein Ghodratollah Shafiei
  The quality of the Asmari Formation, as the reservoir rock of almost three-quarters of the explored oil In Southwest Iran, is often affected by the fractures system. In this paper, in order to study fracture patterns in the Asmari Formation, as well as to present an ana More

  The quality of the Asmari Formation, as the reservoir rock of almost three-quarters of the explored oil In Southwest Iran, is often affected by the fractures system. In this paper, in order to study fracture patterns in the Asmari Formation, as well as to present an analog model for other Asmari reservoirs, the Dara anticline in South Dezful depression, which has extensive outcrops of the Asmari Formation, has been studied. During field studies, eleven stations on the anticline, in its different structural positions, have been investigated. In the southwestern limb, four fracture sets trending AZ40-50,AZ130-140,AZ10-20,AZ80-90, in the northeastern limb four fracture sets trending AZ130-140,AZ50-60,AZ170-180,AZ110-120, and in its hinge area, three fracture sets with AZ50-60,AZ130-140,AZ0-10 trends have been identified. From the structural perspective, all the identified fracture sets are associated with folding. In this study, the relative formation time of the identified fractures relative to folding, has been diagnosed as before or simultaneously with folding. Based on field studies, fractures density in the Dara anticline, the Asmari outcrop, ranges from 11.75 to 2 fractures per meter. Indeed, variation range of the fracture length is 1 to 25 m and most fractures have a length of lower than 5 meters. Also, in this study it was found that there is a negative logarithmic relationship between fracture density and sedimentary layers thickness. Manuscript profile
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  6 - Structural Modeling and Estimation of Tectonic Stresses at Lali Oilfield in Dezful Embayment
  Nasrin kianizadeh Behzad Zamani Rahym khadkhodayi Hoseyn Talebi
  Structural geological study is one of the most important stages of an oilfield exploration and production (E&P) program, since a knowledge of existing structures can play a fundamental role in the oilfield development plan. The main purpose of this study is to create More

  Structural geological study is one of the most important stages of an oilfield exploration and production (E&P) program, since a knowledge of existing structures can play a fundamental role in the oilfield development plan. The main purpose of this study is to create three-dimensional (3D) structural models to determine direction of tectonic stresses at Lali oilfield using subsurface geophysical data. The study area is located within the so-called Dezful Embayment (northern Khuzestan Province, Iran). Accordingly, in order to provide a 3D model of the reservoir, geostatistical tools in Petrel Software were utilized. Incorporating density log data into several coded formulations in MS Excel Software, the reservoir had its modulus of elasticity calculated. Subsequently, maximum and minimum horizontal stresses were calculated using poroelastic equations. Fault modeling results showed that, fault dip increases with increasing the depth towards the center of the field. Obtained values of stress using the poroelastic equations show that σ_H>σ_h>σ_v, confirming a regional reverse stress regime, which is consistent with previous studies in this area. Also, the formal stress ratios (Φ = (σ2-σ3) / (σ1-σ3)) obtained from poroelastic equations and inverse analysis method were found to be well-correlated across the area. Finally, average azimuth of the reverse faults on the southern limb (as calculated by Petrel) and the fractures on the limb (as obtained from FMI images and core samples) were found to be N305 and N315, respectively (average = N310). Thus, N040E was inferred to be the average direction of principal stress, i.e. principal stress is mostly directed along a NE-SW axis (perpendicular to the general trend of Zagros Orogeny); this is probably a result of the activities of youngest Zagros orogeny phase. The agreement between the obtained principal stress directions by fractures, faults, and focal mechanism of earthquakes across the World Stress Map (WSM) confirms the validity of this study. Manuscript profile
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  7 - A review on external coaptation methods in small animal
  pouriya almasi Aboutorab  Tabatabaei Naeini
  External fixation by means of coaptation means using casts, splints, bandages, and slings to immobilize the injured limb. These methods if used properly approximate the shape of the limb on which they are applied and provide stable fixation of bone fragments without the More

  External fixation by means of coaptation means using casts, splints, bandages, and slings to immobilize the injured limb. These methods if used properly approximate the shape of the limb on which they are applied and provide stable fixation of bone fragments without the need for surgical implants at the fracture site. External fixation of orthopedic injuries in veterinary medicine has significant advantages over open fixation and internal fixation. In most cases, the soft tissue and vascular damages, the risk of infection, and the cost of its use can be much lower than surgical intervention. Careful case selection is required to achieve successful treatment of fractures with external coaptation. Temporary fixation methods are usually used to prevent edema, relieve pain, reduce subsequent soft tissue damage, protect the wound from further contamination, prevent the conversion of closed fractures to open fractures, and stabilize the fractured particles in acutely injured animals. Various types of External coaptations are available in veterinary practice to provide the best external fixation of injuries. Therefore, it is essential for the practitioners in this field to have sufficient familiarity with different methods and their uses. As a general rule, external coaptation is an acceptable mode of fracture repair for animals that are younger than 1 year of age, because they heal faster. External coaptation best neutralizes flexion forces on distal fractures and requires stabilization of the joint above and below the fractured site. Therefore, coaptation has the disadvantage of prolonged immobilization of the limb, which can cause severe atrophy from "disuse atrophy" and possible "fracture disease". Manuscript profile
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  8 - Internal Fixation Methods of Bone Fractures in Small Animals
  Arian Pouramin Seifollah  Dehghani
  Bone fractures in dogs and cats are usually see and we concern with those in the clinic. Usually, fractures occur after a traumatic accident such as being hit by a car or falling from a height, some fractures occur following pathological bone weakening, which is seen wi More

  Bone fractures in dogs and cats are usually see and we concern with those in the clinic. Usually, fractures occur after a traumatic accident such as being hit by a car or falling from a height, some fractures occur following pathological bone weakening, which is seen with some neoplastic conditions such as osteosarcoma. The main goals of fracture stabilization; Immobilization of broken parts, quick repair of the damaged bone, return of primary mobility, full function and stability to weight bearing of the bruise limb. All internal and external fixation methods that allow significant intersegmental motion under weight bearing are considered flexible fixation. The best important point in the stabilization of fractures is that a possibility of repair, that is, the blood supply to the place is maintained and the fixation is not so tight that it leads to a delay in bone fusion. Open fixation and internal fixation have been used to restore bone anatomy and original mobility and to overcome the limitations encountered when treating fractures with skeletal traction or cast immobilization. The main goal of internal fixation is to achieve rapid and, if possible, full function of the affected limb with rapid rehabilitation of the patient. The selection of the internal fixation method is based on the classification of the fracture, break bone, synchronize injuries, open fracture, and of course the forces that are neutralized by the fixation method. Internal stabilization implants are made of stainless steel and include; There are intramedullary pins, orthopedic wire, plates and screws. Manuscript profile