University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Integration of 3D seismic attributes and well logs for Asmari reservoir characterization in the Ramshir oilfield, the Dezful Embayment, SW Iran - 1 21 76300 10.22059/geope.2020.295613.648523 EN Rahmat Sadeghi Department of Geology, Faculty of Sciences, Ferdowsi University , Mashhad, Iran Reza Muossavi Harami Department of Geology, Faculty of Sciences, Ferdowsi University , Mashhad, Iran Ali Kadkhodaie Earth Science Department Faculty of Natural Science, University of Tabriz, Iran Asadollah Mahboubi Department of Geology, Faculty of Sciences, Ferdowsi University , Mashhad, Iran Rahim Kadkhodaie Research Institute of Petroleum Industries (RIPI), Tehran, Iran Ahmad Ashtari National Iranian South Oil Company (NISOC), Geophysics Department, Ahvaz, Iran Journal Article 2020 01 10 3D seismic attributes and well logs were used to estimated porosity and water saturation in the Asmari Formation in the Dezful Embayment, SW Iran. For this purpose, at first, the 3D seismic volume was inverted base on the model, to obtain acoustic impedance cube. Afterward, the impedance and other attributes extracted from seismic volume were analyzed by multiple attribute regression transform and neural networks to predict porosity and water saturation between wells. Then linear or non–linear combinations of attributes performed for porosity and water saturation prediction. The result shows that the match between the actual and predicted porosity and water saturation improved; using only a single attribute to the derived multi attribute transforms and neural networks model. Based on the results of neural networks, the highest cross–correlation was observed between seismic attributes and the observed target logs between seven wells in the study area. Based on our study, the cross–correlation between actual and predicted porosity and water saturation increased and reached 93% and 90% respectively in the case of using probabilistic neural networks (PNN). Finally, according to the cross–validation results, PNN neural networks are used for porosity and water saturation prediction. We carry out porosity and water saturation slicing from the Asmari Formation for display lateral and vertical heterogeneities, and the result provided a reliable picture from subsurface formations. Porosity maps distribution shows the western portion of the structure is highly porous and should be considered for further exploration and development purposes. A possible reason for this high porosity in the western portion of the studied formation is the presence of sand layers, especially in zone 2.Note that sand volume increased towards west and northwest in direction of shadegan and Ahvaz fields and decreased towards east and southeast to Rag–e–Sefid field. Based on the result between acoustic impedance and core, changes in acoustic impedance were related to changes in the geological nature of the Asmari reservoir in the field. Accordingly, seismic inversion is a powerful tool for studying the details of lithology and sedimentary facies.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 New insights into the 2017 Sefidsang earthquake by Coulomb stress change pattern and aftershock distributions: implication for active tectonics of NE Iran - 23 42 76373 10.22059/geope.2020.299725.648538 EN Mahnaz Nedaei Department of Geology , Payame Noor University (PNU), 19395-4697 Tehran, Iran Board of directors of geological society of Iran Hasan Alizadeh Department of Geology , Payame Noor University (PNU), 19395-4697 Tehran, Iran Journal Article 2020 03 19 The April 5th 2017 Mw 6.15 Sefidsang earthquake occurred east-northeast of the town of Fariman near the Cimmerian arc-related Fariman complex. The stress distribution was estimated by seismic parameters and Coulomb stress distribution in the source region. Inferred Coulomb stress field and general pattern of aftershocks distribution revealed that the Sefidsang earthquake occurred on a northeast-dipping listric fault with dextral reverse movement. Proximity of the Sefidsang sequence to Fariman complex proposes the reactivation of the pre-existing Cimmerian arc-related faults in the present-day stress field. The crustal-penetrating low-angle inverted faults coupled with Mesozoic mafic–ultramafic magmatism can shed light on the structural aspects of the region. The kinematics was also investigated by GPS velocity fields and morphotectonic features. The counterclockwise block rotation under the left-lateral regional shear between the Doruneh fault system and the North Kopeh Dagh fault system and NE-oriented coeval shortening led to the formation of rhombic structures. Cimmerian-related basement faults in NE Iran confined the expansion of rhombic cells and sense of block rotation. The results of this study improved our understanding about kinematics of active deformation in NE Iran and had important implications for seismic hazard assessment of the region and potential future failure area.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Petrological analysis of the pyroclastic and volcanic rocks in northern Urmia-Dokhtar, northwestern Mahneshan, NW Iran - 43 60 76634 10.22059/geope.2020.296886.648529 EN Mozhgan Salehi Yazdi Department of Earth Science, Science and Research Branch, Islamic Azad University, Tehran, Iran 0000-0002-9730-630x Mansour Ghorbani Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran https://orcid.org/00 Nima Nezafati Department of Earth Science, Science and Research Branch, Islamic Azad University, Tehran, Iran https://orcid.org/00 Mansour Vossoughi Abedini Department of Earth Science, Science and Research Branch, Islamic Azad University, Tehran, Iran https://orcid.org/00 Journal Article 2020 01 29 The study area is part of the northern Urmia-Dokhtar Magmatic Belt. The northern part of this belt consists of andesite, basalt and acidic tuff. There are hyaloclastites with a distinctive bedding only in the northwestern Mahneshan area and northern Urmia-Dokhtar magmatic belt. In this region volcanism began during the Oligocene time with extremely strong hyaloclastite eruptions, and then with a stop, the volcanism continued with exceptionally extensive acidic tuff eruptions, and eventually ended up with basaltic andesite lava eruptions in the late Miocene. Field, mineralogical and petrographic studies on the major and minor minerals of the volcanic and sedimentary rocks indicate that three phases of volcanism occurred in this area. These three phases are: hyaloclastites, acidic tuffs and volcanic Lavas. hyaloclastites (Phase 1), are often composed of andesite and quartz-andesite to dacite. The highly extensive phase 2 consists of acidic tuffs interbedded with limestone. According to the fossil content and the 87Sr/86Sr age determination, this phase formed during the Chattian to Aquitanian ages. Phase 3 includes andesite-basalt, andesite and sometimes quartz-andesite. Based on the geochemical diagrams all three phases are located within the calc-alkaline field, indicating the subduction of an oceanic crust under the continental crust.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Development of the Haraz Road geotourism as a key to increasing tourism industry and promoting geoconservation - 61 79 77005 10.22059/geope.2020.300063.648542 EN Mohsen Ranjbaran School of Geology, Colleges of Science, University of Tehran, Tehran, Iran 0000000300445168 Farzad Sotohian Faculty of Natural Resources, Department: Environmental Science Department, University of Guilan, Iran Journal Article 2020 03 28 The purpose of this research is to introduce road tourist attractions. Geotrial attractions of Haraz Road (Haraz Valley), located in the Alborz Mountain, are presented in this article. The Haraz Road (Road 77) is one of the most beautiful roads in the world that connects the capital of Iran (Tehran) to Mazandaran province. In this research, the geodiversity attractions of the area outside the urban context, in the Jajrud Neck to the Filband zone have been investigated. There are 17 stops along the road. The basis of this research has been the transfer of knowledge and experience of over 20 years of field visits to this road. This research was conducted due to the various interests in the Haraz road, such as geodiversity, cultural, historical, religious, and ecological attractions. The most attractive tourist sites along the Haraz road include Lar plain, Qal'e Dokhtar, Shahandasht waterfalls, Imamzadeh Hashem, Damavand peak Gol-e Zard cave, Damavand Icy waterfall, Basaltic prisms, kafer-Keli crypts, and Shahi Bridge. This road is the cheapest road geotourism option for middle to low-income people. ه

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Hydrochemistry and Stable Isotopes Characteristics of Groundwater in an Urban Aquifer, Southwest of Iran - 81 100 77006 10.22059/geope.2020.294287.648520 EN Hassan Daneshian Faculty of Earth Sciences, Shahid Chamran University of Ahvaz, Golestan Blvd., Ahvaz, Iran Nasrollaha Kalantari Faculty of Earth Sciences, Shahid Chamran University of Ahvaz, Golestan Blvd., Ahvaz, Iran Farshad Alijani Faculty of Earth Sciences, Shahid Beheshti University, Evin, Velenjak, Tehran, Iran Journal Article 2019 12 17 The effect of different recharge sources on the chemical evolution of an urban aquifer, Behbahan plain, southwest of Iran, has been studied using hydrogeochemistry and stable isotopes (18O and 2H). Groundwater samples were collected from 40 water wells in June 2017 and April 2018 as the dry and wet periods, respectively. The water samples were analyzed for the determination of major ions, nitrate, fluoride, and bromide for both periods and stable isotopes concentrations only for the dry period. The main hydrochemical characteristics of groundwater sources in the Behbahan plain were determined as natural groundwater recharge (R) and discharge (D) areas, Marun (M) and Bonehbasht (B) irrigation and drainage networks, contact with gypsum bedrock (G) of the Gachsaran formation, and waste water of Behbahan City (T). The hydrochemical maps of electrical conductivity, chloride, ionic ratios, stable isotopes, and nitrate concentrations was investigated to determine anomalous groundwater zones associated with urban sources of groundwater pollution. Characteristic bivariate composition diagrams and cluster analysis (CA) method were employed to identify the hydrochemical processes and to evaluate the recharge sources. Two major water types Ca–SO4 and Ca (Na)–SO4(Cl) were present in the Behbahan groundwater plain. The high concentrations of SO42–, Ca2+, and Mg2+ were reflected in moderate to high total dissolved solids (TDS) (about 3000 mg/l). The dominant hydrogeochemaical processes in the aquifer were the dissolution of gypsum and somewhat halite, dedolomitization, scant normal and reverse cation exchange, and mixing. The main sources of the nitrate pollution of groundwater were leaching of organic manure applied to cultivated areas as well as wastewater of Behbahan City. The minimum and maximum concentrations of nitrate in groundwater of the Behbahan plain were 5 to 105 mg/Land 5 to 150 mg/L in dry and wet periods, respectively. About one–third of groundwater samples in the Behbahan plain had NO3– concentrations above the drinking water standard (45 mg/L). Five distinct recharge sources were recognized for the Behbahan aquifers based on the characteristics of 2H and 18O isotopes. The hydrochemical characteristics and stable isotope indicators of the groundwater recharge sources are disturbed as a result of the mixing process.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Influence of mechanical parameters and overburden pressure on the mechanical evolution of fault propagation folds: insights from 2D finite-element elastic-plastic models applied to the Ayegan anticline, central Alborz - 101 114 77213 10.22059/geope.2020.297014.648530 EN Anis Khalifeh- Soltani Department of sedimentary and oil basins, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran Seyed Ahmad Alavi Department of sedimentary and oil basins, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran Mohammad R. Ghassemi Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran School of Geology,College of Science University of Tehran, Tehran, Iran Mehdi Ganjiani Department of Mechanical Engineering,University of Tehran, Tehran, Iran Journal Article 2020 02 01 Fault-related folding, due to the variety of tectonic setting, seismic and economic importance, has always been of interest to geologists. In this study, we investigate the influence of different aspects of the mechanical parameters (Young's modulus, Poisson's ratio, dilation angle, and cohesion) and boundary conditions (overburden pressure) to determine the fault-propagation folding style and its mechanical evolution through the use of a series of 2D finite-element elastic-plastic models so that the use of inelastic relationships allows permanent strains to develop in response to the applied loads. All FE-models with the mechanical parameters reduced to 15%, except for Young’s modulus and overburden pressure, lead to lower half- wavelength and amplitude values concerning the reference model, and as these parameters are changed by 15% and 30% simultaneously to validate the results, the area reduction is dramatically increased. FE-model results show that area changes in fault propagation fold are as a function of mechanical stratigraphy, mechanical parameters, and overburden pressure. Area loss can also lead to a decrease in permeability through intergranular mechanisms. We apply these insights to the Ayegan anticline, central Alborz that generally show well-designed FE-modelling matched overall structural geometry in the kink-style kinematic model.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Detection of rare earth element anomalies in Esfordi phosphate deposit of Central Iran, using geostatistical-fractal simulation - 115 130 77352 10.22059/geope.2020.296123.648526 EN Mojtaba Shamseddin Meigooni Department of Earth Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran 0000-0002-1617-9178 Mohammad Lotfi Department of Geology, North Tehran Branch, Islamic Azad University, Tehran, Iran Peyman Afzal Department of Petroleum and Mining Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran 0000-0002-9413-0740 Nima Nezafati Department of Earth Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran Maryam Kargar Razi Department of Chemistry, North Tehran Branch, Islamic Azad University, Tehran, Iran Journal Article 2020 02 05 This study is aimed to determine geochemical anomalies of rare earth elements (REEs) and provides a concentration distribution map for the Esfordi phosphate deposit (EPD), Bafq metallogenic province (BMP), Central Iran. With an average grade of 5519 ppm for REEs, the EPD is one of the prominent deposits of the region. In this research, sequential Gaussian simulation (SGS) and concentration-area (C-A) fractal modeling are used to determine concentration anomalies and provide a ∑REEs concentration map based on surface data. The log-ratio matrix is used to investigate the mineralization processes, determining the relationships between the anomalies and the rock units, and validating the results of SGS fractal modeling. The results are indicating that the main anomaly has strong correlation with the apatite-iron, and in particular, with the apatite mineralization, which can be considered as an exploration guide. The results also confirm the efficiency of simultaneous application of fractal modeling and SGS simulation.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Modeling of land subsidence due to groundwater overexploitation using elastoplastic Mohr-Coulomb model in Arak plain, Iran - 131 151 77492 10.22059/geope.2020.294079.648519 EN Mohammad Hossein Jahangir Department of environment and renewable energies, Faculty of new sciences & technologies, University of Tehran, Tehran, Iran Zahra Kosravi Department of environment and renewable energies, Faculty of new sciences & technologies, University of Tehran, Tehran, Iran Hamid Sarrafha Department of environment and renewable energies, Faculty of new sciences & technologies, University of Tehran, Tehran, Iran Journal Article 2019 12 14 Land subsidence due to groundwater overexploitation has been considered among the natural hazards for the last decades. Accordingly, a growing global concern has been forwarded towards this issue regarding its measurement, prediction, and prevention. In addition to measurement techniques, mathematical and numerical methods could be used for subsidence modelling and its prediction via appropriate software tools and modelling frameworks. As a part of the global trend, groundwater overexploitation and the subsequent land subsidence has lately become a major environmental threat in Iran. In this paper, the land subsidence across Arak plain, a relatively vast plain located in central Iran, caused by groundwater level drop is calculated using Mohr-Coulomb elastoplastic model, which is a structural soil modelling framework. Also, a modified finite element method is applied via PLAXIS 2D commercial software for acquiring further insight and verifying the results from the Mohr-Coulomb model. Accordingly, five borehole stations were considered across the Arak plain, namely Gavkhaneh, Ebrahimabad, Safarabad, Amanabad, and MojedabadKohneh and the mentioned model is applied at each borehole. It was revealed that the axial strain across the plain has reached extreme negative value of -0.190 in 2014, which shows severe soil compaction. Also, the volumetric strain rate reached a minimum value of -0.083 in 2014. The acquired results from the applied Mohr-Coulomb model showed a subsidence average value of 26.6 cm for 17.85 m of groundwater level drop during 1991-2014. Also, the lowest aggregated subsidence value until 2014 was observed at Safarabad station being 0.2 cm, while its maximum value was observed at Gavkhaneh station being 88.75 cm. These was a 9.20% of difference between the average value acquired by Mohr-Coulomb model and FEM, which, considering the uncertainty in measured input data verifies the reliability of the model. The research findings prove the capability of the Mohr-Coulomb model in modelling land subsidence.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Reservoir lithofacies modeling using well logs and seismic data based on Sequential Indicator Simulations and Probability Perturbation Method in a Bayesian framework - 153 168 77781 10.22059/geope.2020.301568.648549 EN Mohamadreza Shad Salanghouch Institute of Petroleum Engineering, College of Engineering, University of Tehran, Tehran, Iran Mohammad Emami Niri Institute of Petroleum Engineering, College of Engineering, University of Tehran, Tehran, Iran Journal Article 2020 04 25 In this paper, an inverse framework based on Bayes’ theorem is suggested for integrating well logs and seismic data into reservoir lithofacies modeling process. The proposed method is based on combination of the Sequential Indicator Simulation (SIS), and a stochastic optimization method (i.e. Probability Perturbation Method (PPM)). SIS is used to calculate the conditional probability of presence/absence of lithofacies indicators in each grid-block, and PPM is applied to update (perturb) the conditional probability used in SIS. A notable innovation presented in this study is using the Genetic algorithm’ crossover operator to increase the PPM exploitation capability. To demonstrate the efficiency of our proposed approach, the results of its application on a 3D test model is compared with outcomes of two commonly-used constraining approaches on SIS. Qualitative and quantitative analysis of the obtained results on 3D test model reveals a (23.8)% and (16.98)% (on average) improvement in consistency of lithofacies models generated using the proposed approach with the reference lithofacies model over the employed Vertical Probability Trend and Seismic Probability Trend constraining approaches on SIS, respectively. Besides, the obtained results show that implementing crossover operator leads to a 4.56% improvement in matching of the constructed lithofacies models with the reference model.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 The Sedimentological Record of Upper Holocene Tsunami Event in Fengbin, Taiwan - 169 203 77887 10.22059/geope.2020.301603.648548 EN FX ANJAR TRI LAKSONO Department of Geological Engineering, Jenderal Soedirman University, Kalimanah, Purbalingga, Indonesia 0000-0002-6061-6136 Louis Loung Yie Tsai Graduate Institute of Applied Geology, National Central University, Taoyuan, Taiwa Jessica Pilarczyk Department of Earth Sciences, Simon Fraser University, Burnaby, B.C. Canada Journal Article 2020 04 25 A tsunami had struck the Ami tribe’s settlement on the eastern coast of Taiwan in 1771. The trigger of this tsunami is still debatable. Hence, the analysis of tsunami deposits in Fengbin is needed to understand the chronology of the tsunami. There are three types of sediment samples taken from the study area, namely modern beach sand, modern fluvial sand, and sediment materials from the marine terrace. Sample analysis was carried out using the point counting, granulometry, biozonation, and paleo-bathymetry methods to determine the facies, provenance, and sediment transport mechanisms. The results of field observation indicate the presence of marine shells on the sediment deposit of marine terraces at elevations between 10.5-12.5 m. The thickness of this deposit is between 15-20 cm in the fining upward succession and there is a rip-up clast sedimentary structure. The characteristic of this deposit is similar to tsunami deposits found on the Ishigaki and Miyako Islands, Japan. The conclusion of this study is that there is a tsunami deposit in Fengbin associated with the tsunami deposits found in Miyako and Ishigaki Islands, Japan. The trigger of the tsunami in Fengbin probably attributed to tectonic activity in the Ryukyu Trench.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Mineralogical reconstruction of Late Pleistocene - Holocene climate and environmental changes in southern wetlands of Lake Urmia - 205 218 78248 10.22059/geope.2020.306217.648565 EN Bita Mirzapour Department of Earth Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran Razyeh Lak Research Institute for Earth Sciences, Geological Survey of Iran (GSI),Tehran, Iran Mohsen Aleali Department of Earth Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran Morteza Jamali 3 Institut Méditerranéen de Biodiversité et d'Ecologie (CNRS/IRD/Aix-Marseille Univ., Avignon Université), Aix-en-Provence, France Reza Shahbazi Engineering Environmental Geology and Hazards Department, Geological Survey of Iran, (GSI), Tehran, Iran Journal Article 2020 07 16 To determine the effect of climate changes on current critical conditions of Lake Urmia, paleoclimate of southern wetlands of Lake Urmia was investigated based on clay mineralogy. Kani Barazan and Solduz wetlands on the southern margin of Lake Urmia and also the southern part of the lake have been briefly studied in this research. A total of 24 sedimentary cores were taken for sedimentology and mineralogy study from south to north of Lake Urmia. The clay mineralogy analysis were done by XRD method. The main minerals in the sediments include quartz (over 40%), calcite, feldspars, mica, dolomite and clay minerals. Chlorite and kaolinite were the main clay minerals in the southern coastal plains of Lake Urmia. Distribution of surface samp les represents reduction of clay minerals in the sediments from the margin to the center of the basin. This indicate that the percentage of detrital sediments decreases and chemical sediments increase from the margin to the center. Increasing the distance from the edge of the wetland causes it to move away from the source of the sediments. The concentration of water salts in the central part of the basin increases. In the central part of the lake, due to greater depth and high salinity of water, chemical sediments have been predominant and in the margins of the lake, according to low salinity and the volume of clastic materials, this kind of sediments have been predominant. This is consistent with the changes in other clastic minerals (quartz) in the lake. The level of clay minerals increased from the surface to the depth of boreholes indicating a high water level and a more warm–wet paleoclimate. According to the changes in the type of clay minerals in the sediment sequence of the southern part of Lake Urmia, it seems that in the Late Pleistocene (20 cal ka BP) the weather was more humid than the current conditions and the volume of clastic material to the lake was higher.

University of Tehran Geopersia 2228-7817 11 1 2021 06 01 Depositional and diagenetic impact on reservoir quality of the Asmari carbonate reservoir, Naft-Sefid Oilfield, SW Iran - 219 243 78735 10.22059/geope.2020.309894.648576 EN Abdolmotaleb Haghighat Department of Geology, Science and Research Branch, Islamic Azad University, Tehran, Iran Mohsen Aleali Department of Geology, Science and Research Branch, Islamic Azad University, Tehran, Iran Nader K. Ghadimvand Department of Geology, Science and Research Branch, Islamic Azad University, Tehran, Iran Davood Jahani Department of Geology, Science and Research Branch, Islamic Azad University, Tehran, Iran Zahra Maleki Department of Geology, Science and Research Branch, Islamic Azad University, Tehran, Iran Journal Article 2020 09 12 The Oligo-Miocene Asmari Formation is the most prolific reservoir in the Dezful Embayment, southwest of Iran. Depositional and diagenetic effects on reservoir quality in the sequence stratigraphic framework were carried out on the basis of petrographic investigation, petrophysical logs, and core measurement porosity and permeability data. Petrographic analysis resulted in the identification of 12 microfacies classified in 5 sub-environments including tidal flat, lagoon, barrier, shallow open marine and basin, which indicate deposition in a homoclinal ramp setting. Tidal flat, lagoonal and barrier microfacies are mostly present in the upper and middle parts of the Asmari Formation, while outer ramp microfacies largely developed in the middle part. Anhydrite and calcite cementation, compaction, dolomitization, dissolution, and fracturing are the main diagenetic controlling factors on petrophysical properties. Fracturing, dolomitization, and dissolution are contributed to reservoir quality enhancement, while compaction and cementation had negative effects on reservoir quality. The studied successions are represented by 3 third-order sequences of early Aquitanian, late Aquitanian and early Burdigalian ages that largely deposited in the highstand systems tract (HST) stage