Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Ore Facies of Khanjar Pb– Ag (Zn) Carbonate– Hosted Deposit ,Upper Cretaceous Sequence in Central Iran, South Damghan, Iran
3
12
FA
B.
Mehri
Metalic Exploration Department, Geological Survey of Iran, Tehran, Iran.
E.
Rastad
Economic Geology Department, Tarbiat Modarres University, Tehran,Iran
rastad@modares.ac.ir
F.
Fayyazi
Geology Department, Tarbiat Moallem University,Tehran,Iran.
10.22071/gsj.2010.55420
<span style="font-family: Times New Roman;">The Khanjar Pb– Ag (Zn) deposit is one of the stratabound deposits of Cretaceous age in Central Iran. The ore bodies may be grouped into two main geometric types: 1) Lenses of ore bodies congruent with bedding, 2) Ores as open space filling or with brecciate fabric due to faulting. Both types occur in limestone unit (k2b).Three ore bearing facies have been distinguished in the Khanjar area: 1) Siliceous limestone facies; galena, sphalerite and pyrite are the main ore minerals. Minor amounts of chalcopyrite are also visible. 2) Mullusca, Echinoderm wackstone facies with galena and sphalerite. 3) Rudist limestone facies with large amount of galena. As with other stratabound and stratiform Pb- Zn deposits, the main ore minerals are simple and few in number. In addition, galena, sphalerite and pyrite, some tetrahedrite, barite and minor amounts of copper minerals are observed. Pyrite often with framboidal texture and sphalerite with spheroidal texture form always part of paragenesis. Fluid inclusion investigations on saddle dolomite located in fractures with galena and sphalerite demonstrated the homogenization temperature of 145-230 centigrade and salinity of 17.5-23% NaCl equivalent.Geometry of ore bodies, occurrence of ore horizons in certain sedimentary facies, ore textures and structures, depositional environment (Lagoonal), paragenetic sequence of minerals and fluid inclusion data, all suggest that Khanjar Pb- Ag(Zn) deposit is an MVT deposit.</span>
<span style="font-family: Times New Roman;"> </span>
: Pb– Ag (Zn)deposit,Upper cretaceous carbonate units,Ore facies,MVT,Khanjar(Reshm),South Damghan
http://www.gsjournal.ir/article_55420.html
http://www.gsjournal.ir/article_55420_2f8cdd92702739a089836c832a6cd0f1.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
The Study of Permian-Triassic Boundary in Esfeh Section N.E. Shahreza (Central Iran)
13
18
FA
M.R.
Partoazar
Geological Survey of Iran, Tehran, Iran
mpartoazar@yahoo.com
10.22071/gsj.2010.55422
<span style="font-family: Times New Roman;">The stratigraphic section of Esfeh is located at 15 km north-east of Shahreza and 65 km south of Esfahan. The aim of this study is to consider the lithostratigraphy, biostratigraphy and how to settle the Permian-Triassic boundary, also the geochronology of them. The biostratigraphic study of this section indicates the existence of index Fusulinidae with the high quality of other places. for instance:<em>Verbeekina verbeeki , Sumatrina annae , Afghanella schenki , Yangchienia iniqua ,</em><em> Eoparafusulina Shengi.</em>In this study the geochronological change of member 3 of the Surmagh Formation with attention to index fossils attributed from Guadalupian to Early Julfian and also the lithoiogical alterations to exist in deposits of the Hambast Formation equivalent to Esfeh section, the Shahreza formation propose is necessary.</span>
Esfeh Section,Permian-Triassic Boundary,Member 3 of Surmagh Formation,Shahreza formation
http://www.gsjournal.ir/article_55422.html
http://www.gsjournal.ir/article_55422_c8a573f2cbdeb2128495bd86fd859839.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Comparison of Seismic, Geologic and Geodetic Moment Rates in Central Alborz
19
24
FA
M.
Asadi sarshar
Research Institute for Earth Science, Geological Survey of Iran, Tehran, Iran
maryamsarshar7@yahoo.com
A.
Bahroudi
School of Mininig Engineering, University of Tehran, Tehran, Iran
bahroudi@ut.ac.ir
M.
Qorashi
0000-0002-1600-0350
Research Institute for Earth Science, Geological Survey of Iran, Tehran, Iran
ghorashi_manouchehr@yahoo.com
M. R.
Ghassemi
Research Institute for Earth Science, Geological Survey of Iran, Tehran, Iran
mrghassemi@yahoo.com
10.22071/gsj.2010.55424
<span style="font-family: Times New Roman;">Estimate of moment rate is comparatively reckoned as a new method for dealing with tectonic activities rate in different regions and it prepares the way for putting together different methods. In fact, moment rate states rate of energy which exists in deformation system. There are three different approaches to state moment rate that each one express tectonic motion and movement of a region from a particular view. These three approaches consist of: geodetic (surveying), seismic and geology methods. Geodetic method which is determined on the basis of gained strain rate tensor from geodetic data, shows deformation rate (including seismic and aseismic) that is happening in the region at this moment in time. Moment rate which has gained on the basis of historical and instrumental catalogues, shows the total released seismic energy during quake events which are available in earthquake of region and geologic moment rate which gained with geometric parameters of faults, reveals potential of the faults in releasing stored elastic energy in. Geodetic moment rate, seismic moment rate (on the basis of historical and instrumental earthquake data) and geologic moment rate are estimated for Central Alborz region. The most moment rate in the study area belongs to geodetic approach (8.83×10<sup>19</sup> Nm/yr) and then geologic moment rate (0.12×10<sup>19</sup> Nm/yr) and finally the least quantity belongs to seismic moment rate (0.022×10<sup>19</sup>- 0.046×10<sup>19</sup> Nm/yr). Considering, distribution of earthquake epicenters, the most seismic energy is released in the south parts of Central Alborz and considering high geodetic and geologic moment rates in north parts, it seems, north parts of Central Alborz have higher seismic potential. </span>
Moment Rate,Central Alborz,Energy,Earthquake,Strain Rate
http://www.gsjournal.ir/article_55424.html
http://www.gsjournal.ir/article_55424_3ac7df33125055bb3ba25a3e8c35ce21.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Biostratigraphy of the Abderaz Formation at Type Section Using Planktonic Foraminifera
25
34
FA
M.
Shafiee Ardestani
Faculty of Science, Department of Geology, Ferdowsi University of Mashhad, Mashhad, Iran
m_shafiee@khayam.ut.ac.ir
E.
Ghasemi-Nejad
College of Science, Faculty of Geology, University of Tehran, Tehran, Iran
eghaseminejad@khayam.ut.ac.ir
H.
Vaziri Moghaddam
Faculty of Science, Department of Geology, University of Esfahan, Esfahan, Iran
avaziri7304@gmail.com
10.22071/gsj.2010.55427
<span style="font-family: Times New Roman;">In order to study the fossil contents of the Abderaz Formation for biostratigraphical purposes the 300 meters thick section was sampled at type section. The sequence is mainly made up of grey shales and marls with two units of chalky limestone in upper part. The lower contact of the formation with Aitamir Formation is disconform while the upper contact with Abtalkh is continuous. Fifty six species belonging to 16 genera were identified and four biozones were differentiated. These are: <em>Helvetoglobotruncana helvetica</em> (Sigal)total range Zone, 2-<em>Marginotruncana sigali - Dicarinella primitiva</em> (Premoli Silva and Sliter)<em> Partial</em> range Zone, 3- <em>Dicarinella concavata </em>(Sigal)interval Zone and4-<em>Dicarinella asymetrica </em>(Postuma)total range Zone. Based on, these an age of Turonian-early Campanian is quoted to the formation. Also it was shown that <em>Helvetoglobotruncana helvetica</em>, the index species for middle Turonian exists at the base of the formation while, in the samples immediately below this belonging to Aitamir Formation <em>Rotalipora appenninica</em>, the index for middel cenomanian was recorded. Therefore, lack of index species for late Cenomanian- early Turonian shows a gap spanning this period between the Aitamir and Abderaz Formations. This could be a result of sub Hersinian orogeny.</span>
Abderaz Formation,Biostratigraphy,Sub Hersinian Orogeny,Planktonic Foraminifera,Biozone
http://www.gsjournal.ir/article_55427.html
http://www.gsjournal.ir/article_55427_642001525afe8f2dd4a281b92fdf992a.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Focal Mechanism of December 20, 2007, Tabriz Earthquake Using Accelerograph Data
35
38
FA
H.
Hamzehloo
International Institute of Earthquake. Engineering and Seismology, Tehran, Iran
hhamzehloo@iiees.ac.ir
E.
Farzanegan
Building and Housing Research Center, Tehran, Iran
H.
Mirzaei
Building and Housing Research Center, Tehran, Iran
10.22071/gsj.2010.55429
<span style="font-family: Times New Roman;">The December 20, 2007 earthquake has occurred three months after the September 16, 2007 earthquake near the Tabriz city in East Azarbaijan province. We have used SH- waves accelerographs data and Brune model to estimate the causative fault plane parameters. The strike, dip and rake have been estimated as 310<sup>o</sup>, 85<sup>o</sup> and 170<sup>o</sup>, respectively. The focal mechanism shows right- lateral strike slip, which is consistent with the North Tabriz Fault. This is the first focal mechanis for the North Tabriz fault based on the strong ground motion data.</span>
SH- Waves,focal mechanism,North Tabriz Fault
http://www.gsjournal.ir/article_55429.html
http://www.gsjournal.ir/article_55429_17761a319f0f25f09a5b269a79eaa2ed.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Structural Analysis of Simin-Darreh Moradbeik Shear Zone,South of Hamedan
39
46
FA
L.
Izadi kian
University of Bu-Ali Sina, Faculty of Science, Department of Geology, Hamedan, Iran
izadikian@yahoo.com
A.
Alavi
University of Shahid Beheshti, Faculty of Earth Science, Department of Geology, Tehran, Iran
M.
Mohajjel
University of Tarbiat Modarres, Faculty of Science, Department of Geology, Tehran, Iran.
mohajjel@tmu.ac.ir
10.22071/gsj.2010.55432
The Simin- Darreh Moradbeik shear zone is located in the south of Hamedan city with 5 km width and at least 10 km length. The portion of contact metamorphic rocks, plutonic rocks and migmatits are affected by this shear zone. At least three ductile deformation stages are recognized by folding and foliation of each stages of deformation. All of deformation stages are coaxial and created interference pattern of folding. Field evidence shows tension and shear stress in this area. The shear zone dips to northeast and northwest with normal sense of shear movement. This shear zone deformed locusom of migmatite, boudinage of andalusite porphyroblast and formed granitic mylonite from Khako granite. Distribution of mylonitic foliation poles show refolding of this shear zone at the next deformation stages. According to deformation stages in Hamadan tectonites, possibly this shear zone formed syn to post second deformation (D2)
Shear zone,Migmatit,Ductile deformation,Hamedan
http://www.gsjournal.ir/article_55432.html
http://www.gsjournal.ir/article_55432_4b5aac49e97176340e3eade2e7f828ed.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Calculation and Interpretation of Some Morphotectonic Indices Around the Torud Fault, South of Damghan
47
56
FA
M.
Khademi
Damghan University of Basic Sciences, Damghan, Iran.
khademi@dubs.ac.ir
10.22071/gsj.2010.55433
<span style="font-family: Times New Roman;">The only geologic evidence of the neotectonic activity of theTorud region is its seismisity which assumed to be related to the Torud seismogenic fault. This fault has been overlain by the Quaternary alluvium in the major part of its length. Therefore, the study of morphotectonical characteristics of the region gives more evidences about its activity. Calculation of three morphotectonic indices including stream length – gradient ( SL) and ratio of valley – floor width to valley height (Vf)</span> <span style="font-family: Times New Roman;">of stream channels and mountain front sinuosity (Smf)</span> <span style="font-family: Times New Roman;">shows high SL values</span> <span style="font-family: Times New Roman;"> (425 – 1044) and low Vf (2.68 – 3.34) and Smf (1.05 – 1.44) values and indicate that the region has activity specially at two parts: central part (near the mountain front ) and northwestern part ( near the main divide of the Torud mountains)</span> <span style="font-family: Times New Roman;"> and therefore the tectonic activity class of the region can be number 1. The activity of the central part can be due to the movements of the Torud fault. The activity of the northwestern part is the result of the uplift of the region which is related to</span> <span style="font-family: Times New Roman;">the at least one fault parallel with the Torud fault that has formed the relic mountain fronts at recent past. The distribution of strain of this activity shows the progressive deformation from north northwest to south southeast and from west to east.</span>
<span style="font-family: Times New Roman;"> </span>
The Torud Fault,Morphotectonics,Neotectonics,SL,Vf and Smf Indices
http://www.gsjournal.ir/article_55433.html
http://www.gsjournal.ir/article_55433_dbdec791eb71449e75c9cadeb3fb4fdb.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
The ،Tectonic Geomorphology and Seismotectonics of the Ravar Fault Zone, South of Central Iran
57
66
FA
A.
Shafiei Bafti
Tectonic group,Islamic Azad University Zarand Branch, Kerman, Iran
amir.shafii@gmail.com
M.
Shahpasandzadeh
Geophsics group, graduat University and Technical of Keman, Kerman, Iran.
m.shahpasandzadeh@kgut.ac.ir
10.22071/gsj.2010.55436
According to potential of the intra-continental strike-slip faults for occurrence of large earthquakes, which are also considered as the main elements of active continental deformation, determination of their geometry and kinematics along with recognition of the active segments and temporal structural evolution is necessary. The oblique-slip fault of Ravar with about 137 km length is extending in vicinity of Ravar, north of Kerman. In the north of study area, the fault extends parallel to the Lakar-Kuh fault, but in the south converges toward to the Lakar-Kuh and the Kuh-Banan faults. Upthrusting of the eastern block of the Ravar fault and east-ward thrusting of the Lakar_Kuh fault system constructed a positive flower structure. The motion of the Ravar fault have caused the dextral displacement and an accumulative horizontal displacement of the drainages about 940-970 in the north since Pleistocene. Regarding a minimum horizontal slip-rate of about 0.54 mm/yr, the recurrence time of earthquakes with Mw~ 6.7 would be about 1400 year. In the middle part of the fault, the Reidel fractures of R, R, and P has been well developed and caused a dextral deflection of the Esmail-AbadRiver about 16m. With assumption of characteristic earthquake occurrence, the maximum slip per event could be about 0.75 m, which is consistent with the minimum displacement of the recent gorges. The amount of horizontal dextral displacement of the fault decreases toward to the south, whereas the vertical component of the fault motion increases, so that the Pleistocene deposits show about 10 m difference in elevation across the southern part of the fault. Concerning the trend of meizoseismal zone of 1911/04/18 Ravar earthquake (M~ 5.8, I<sup>0</sup>~ VIII) and parallelism of trend of the co-seismic surface rupture (N13W) with the southern part of the fault, the Ravar fault could be responsible of this earthquake. In addition, the active cross-faulting of the Dehu, the Dehzanan, the Chatrud, the Pasib, and the Darbid-Khun control the recurrence time and magnitude of the earthquakes in the study area.
Strike-slip faults,Segmentation,Active fault,Tectonic geomorphology,The Ravar fault zone,Central Iran
http://www.gsjournal.ir/article_55436.html
http://www.gsjournal.ir/article_55436_281b526be4871f5ba13db6411b549ff7.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Geomorphic Signatures of Active Tectonics in the Karaj Drainage Basin in South Central Alborz, N Iran
67
74
FA
R.
Khavari
Islamic Azad University (IAU), Science and Research Branch, Tehran, Iran
re_khavari@yahoo.com
M.
Ghorashi
0000-0002-1600-0350
Islamic Azad University (IAU), North Tehran Branch, Tehran, Iran
Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran
ghorashi_manouchehr@yahoo.com
M.
Arian
Islamic Azad University (IAU), Science and Research Branch, Tehran, Iran
mehranariyan@yahoo.com
Kh.
Khosrotehrani
Islamic Azad University (IAU), Science and Research Branch, Tehran, Iran
10.22071/gsj.2010.55438
<span style="font-family: Times New Roman;">The paper presents a method for evaluating relative active tectonics based on geomorphic indices useful in evaluating morphology and topography. Indices used include: stream length-gradient index (SL), drainage basin asymmetry (Af), hypsometric integral (Hi), ratio of valley-floor width to valley height (Vf), index of drainage basin shape (Bs), and index of mountain front sinuosity (Smf). Results from the analysis are accumulated and expressed as an index of relative active tectonics (Iat), which divided into four classes from relatively low to highest tectonic activity. The study area along the south flank of the central Alborz mountain range in north Iran is an ideal location to test the concept of an index to predict relative tectonic activity on a basis of area rather than a single valley or mountain front. The recent investigations show that neotectonism has played a key role in the geomorphic evolution of this part of the Alborz mountain range. Geomorphic indices indicate the presence of differential uplifting in the geological past. The high class values (low tectonic activity) for Iat mainly occur in the south and southeast of the Karaj drainage basin, while the rest of the study area has classes of Iat suggesting moderate to high tectonic activity. Around the Amirkabir Lake, Iat has the highest value. The distribution of the indices defines areas associated with different mountain fronts and estimates of relative rates of tectonic activity. More than half of the study area is classified into classes 2 or 1 of high to very high tectonic activity in terms of the apparent geomorphic response. In different tectonic environments with greater rates of active tectonics, the values of indices would differ as well as their range in value. The stream network asymmetry (T) was also studied using morphometric measures of Transverse Topographic Symmetry. Analysis of the drainage basin and a number of sub-basins in the study area results in a field of T-vectors that defines anomalous zones of the basin asymmetry. We test the hypothesis that areas with great stream migration are associated with indicatives values of Iat. </span>
<span style="font-family: Times New Roman;"> </span>
Geomorphic Indices of Active Tectonics,Drainage Basin,Asymmetry,Central Alborz
http://www.gsjournal.ir/article_55438.html
http://www.gsjournal.ir/article_55438_cc7b7f06a96b43e546a4715fea86e319.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Folding Style in Kermanshah Radiolarites and its Significance in Collision Tectonic of Northwest Iran
75
82
FA
M.
Mohajjel
Tectonic Group, Tarbiat Modares University, Tehran, Iran.
mohajjel@tmu.ac.ir
M.
Biralvand
Tectonic Group, Tarbiat Modares University, Tehran, Iran.
m.biralvand@modares.ac.ir
10.22071/gsj.2010.55439
Abundant chevron folds were produced in well-bedded red thin layers radiolarites in Kermanshah area. Various fold hinge area structures were produced due to competency contrast and change of thickness in radiolarian shale and thick-bedded limestone intercalation in radiolarite sequence. Different styles of folding exist in massive to thick-bedded limestone and shale where they are inter-bedded with radilarites. Unique thin layers of the radolarite layers were folded in parallel shape but change of folds shape and mechanism were produced where thick bedded limestone or thin layers of radiolarian shale intercalations exist. Fold accommodation faults were generated in cases during folding. Geometry and style of folding indicate that deformation in radiolarites was produced by parallel folding due to buckling mechanism with southwest vergence. Thrust faults were generated during later stages, displacing some parts of the folded radiolarites.
Folding,chevron folds,Radiolarite,Collision tectonic,Thick-skinned tectonic,Kermanshah
http://www.gsjournal.ir/article_55439.html
http://www.gsjournal.ir/article_55439_a0e8477957f82667bb65b02f99940ef5.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Application of SOM Neural Network for Numerical Tectonic Zoning: A New Approach for Tectonic Zoning of Iran
83
88
FA
Ahmad
Zamani
Earth Sciences Department, Faculty of Sciences, Shiraz University, Shiraz, Iran
zamani_a_geol@yahoo.com
M.
Nedaei
Earth Sciences Department, Faculty of Sciences, Shiraz University, Shiraz, Iran
10.22071/gsj.2010.55441
One of the basic discussions in geosciences is construction of different tectonic zoning maps. In conventional tectonic zoning, not only the great amounts of subjective judgment are involved but also accurate interpretation of high-dimensional data is so difficult and out of human capability. To alleviate these deficiencies, quantitative scientific methods in data mining domain can be applied as an effective and useful tool to construct the new numerical maps in geosciences. In this paper self-organizing map (SOM) neural network that is one of the common methods in data mining has been applied for numerical tectonic zoning of Iran. SOM is an unsupervised artificial neural network particularly adept at pattern recognition and clustering of high-dimensional data. Visualization of high-dimensional data in two-dimensional topological-preserving feature map is another specific capability of SOM that represent both homogeneity within and similarity between clusters. Although there are some similarities between SOM's numerical maps constructed here and the conventional maps but SOM method is more powerful for identification and interpretation of different zones than conventional methods. Utilizing SOM method enables us not only to evaluate the degree of homogeneity in each zone, but also to separate regions zone that experience similar geological evolutionary despite of their geographical locations. For instance Lut and Gavkhuni zones show more homogeneity than Makran and Azerbayejan zones also Kopeh-Dagh and Zagros are located at different regions, they have similar features. The results obtained here represent separation between Makran from EastIranianRanges and Western Azerbaijan from AlborzRanges, too. It is important to recognize that the SOM's results are based purely on the geophysical, geological and seismic features presented previously. So correspondences and differences between the SOM's zones and a given zone based on conventional method must receive careful thought.
Tectonic Zoning,Clustering,Self-Organizing map,Neural Network
http://www.gsjournal.ir/article_55441.html
http://www.gsjournal.ir/article_55441_63db464d8ae9b9630fc9a07b531e90d6.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Lithostratigraphy and Biostratigraphy of the Dalichai Formation (Middle Jurassic) in Parvar Area, North of Semnan, Central Alborz
89
94
FA
M.
Shams
School of Geology , University College of Science , University of Tehran, Tehran, Iran
me_shams59@yahoo.com
K.
Seyed-Emami
School of Mining Engineering, University Collage of Engineering, University of Tehran, Tehran, Iran
kemami@ut.ac.ir
10.22071/gsj.2010.55443
<span style="font-family: Times New Roman;">The Dalichai Formation and its ammonite fauna is studied for the first time in the Parvar area, Central Alborz. At Parvar the Dalichai Formation, with a thickness of about 70 m, consist of an alternation of grayish silty marls, marlstones, marly limestone and limestone and is subdivided into 5 members. A rich ammonite fauna (407 specimens) have been collected from the member 4 and 5, comprising the following families: Phylloceratidae, Lytoceratidae, Oppeliidae, Haploceratidae, Sphaeroceratidae, Parkinsoniidae, Morphoceratidae and Perisphinctidae. These indicate a Late Bajocian and Bathonian age. Member five consists of greenish to reddish, nodular and flaggy limestones and is a typical condensed horizon.</span>
<sub></sub>
Lithostratigraphy,Biostratigraphy,Dalichai Formation,Ammonite,Middle Jurassic,Parvar,Central Alborz
http://www.gsjournal.ir/article_55443.html
http://www.gsjournal.ir/article_55443_6e44e405d3880524f0ef619241e92848.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Evaluation of Organic Geochemical Characteristics of Kangan Formation in South Pars Field
95
102
FA
A.
Rajabi-Harsini
Islamic Azad University- North Tehran Branch, Tehran, Iran
arh7948@yahoo.com
M.
Memariani
Research Institute of Petroleum Industry, Tehran, Iran
memarianim@ripi.ir
10.22071/gsj.2010.55447
In this study, in order to evaluate the geochemical characterization of Kangan Formation in well B in South Pars Gas Field, geochemical analysis (including preliminary and complementary analysis such as Rock-Eval Pyrolysis, extraction of organic matter (EOM), bitumen fractionation, Gas chromatography and Gas chromatography-Mass Spectrometry) were carried out on core samples. Geochemical results reveal that these samples have kerogen type III and II, indicating a marine organic matter with a little terrestrial input. The organic matter of these samples was derived from source rock(s), with clastic-carbonate lithology which deposited under anoxic to subanoxic conditions. In addition, the above samples exhibt poor to moderate genetic potential with kerogen maturity at the beginning of oil generation (late diagenesis to early catagsnesis). Also, based on column chromatography, the above samples are mainly composed of paraffinic-naphthenic and paraffinic hydrocarbons. A negligible amount of hydrocarbons seems to have been generated locally from Kangan Formation.
Kangan Formation,Rock-Eval pyrolysis,Gas Chromatography,Gas Chromatography-Mass Spectrometry,Source rock
http://www.gsjournal.ir/article_55447.html
http://www.gsjournal.ir/article_55447_2063991a0f1454157a8429e7adb4f699.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
The Environmental Impacts of Mining in Olang Area, Golestan Province (South Ramian)
103
108
FA
N.
Hafezi Moghaddas
1980-07-01 to 1983-06-01
Shahrood University of Technology, Shahrood, Iran
nhafezi@um.ac.ir
G. A.
Kazemi
Shahrood University of Technology, Shahrood, Iran.
H. R.
Amiri Moghaddam
Shahrood University of Technology, Shahrood, Iran
R.
Sanchooli
Rural Water and Wastewater Company, Golestan, Iran.
F. S.
Hejazi Nejad
Rural Water and Wastewater Company, Golestan, Iran.
10.22071/gsj.2010.55448
<span style="font-family: Times New Roman;">Olang Coal Mines in the Ghareh Chai watershed are located 100-130 km far from Gorgan and 20 km to the south of Ramian. In this research, the environmental impacts of these mines in this region including impacts on soil and water resources, slope instability and river bed erosion have been investigated. To evaluate the effects of mine drainage and surface pollutants, 34 water samples were collected in two different seasons, spring and summer. The samples were collected from mine drains and upstream and downstream of the junction points of such drains with streams, and subjected to analysis for chemical constituents. The results have shown that mine drainage has increased salinity and organic content of natural streams, but it has not significantly affected the concentration of heavy metals and other constituents. The most polluted samples are those located close to the dumps. This suggests that improper disposal of mine dumps, which are extensive in the area, is the main cause of soil and water pollution. Therefore, proper sealing of such dumps and optimum management of mine drainage is needed to minimize the negative impacts of coal mining. To evaluate the slope instability and land sliding associated with mining activities, first of all, the position of all land slides were located and mapped. The causes of each landslide were then identified. The analysis shows that land sliding is more common in the mining areas, and human activity together with natural causes such as geology, climate and hydrology play important roles in the occurrence of landslides.</span>
Environmental effects,Mining,Olang,Golestan province
http://www.gsjournal.ir/article_55448.html
http://www.gsjournal.ir/article_55448_417a31e6c5cff26974eb2c08f8542442.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Dynamic Fracture Process of Bam Earthquake
109
114
FA
M.
Eskandari
University of Tehran, Institute of Geophysics, Tehran, Iran
eskandary@nt.ac.ir
M. R.
Gheitanchi
University of Tehran, Institute of Geophysics, Tehran, Iran
mrghchee@ut.ac.ir
10.22071/gsj.2010.55451
<span style="font-family: Times New Roman;">In this article, we studied the dynamic fracture process of Bam earthquake. In two presented models stress heterogeneity on the fault plain was modeled as barrier or asperity and friction included as slip-weakening relationship. Results of models were constrained by near field ground motion recorded in Bam station. In the first model, fracture starts form a weak asperity which its waves surround the neighbor barrier and break it down. In the second model, another asperity is included in southern part of the fault. Breaking barrier releases two fracture fronts traveling in two different regimes. One of them travels faster than shear waves and goes to the intersonic velocity. The other front travels with 0.74 shear wave velocity and makes the largest pulse of the record. Both models predict the slip rate successfully, but the second model is more consistent with the real data.</span>
Dynamic Fracture,Bam earthquake,Fracture front,Stress heterogeneity
http://www.gsjournal.ir/article_55451.html
http://www.gsjournal.ir/article_55451_9ca9328c4814428278511ea273900655.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Definition and Comparison Improved Mundry’s Integral with Mundry’s Integral on HEM Data Inverse Modeling
115
118
FA
A.R.
Arab-Amiri
Faculty of Mining, Petroleum and Geophysics, Shahrood University of Technology, Shahrood, Iran.
aamiri@gsi.ir
A.
Moradzadeh
Shahrood University of Technology, Faculty of Mining, Petroleum and Geophysics, Shahrood, Iran.
a_moradzadeh@ut.ac.ir
D.
Rajabi
Shahrood University of Technology, Faculty of Mining, Petroleum and Geophysics, Shahrood, Iran.
B.
Siemon
Federal Institute for Geosciences and Natural Resources (BGR), Hannover, Germany.
N.
Fathianpour
Isfahan University of Technology (IUT), Faculty of Mining Engineering, Isfahan, Iran.
10.22071/gsj.2010.55453
It is about 30 years that Helicopter electromagnetic (HEM) surveys are being used for rapid mineral and ground water exploration, environmental investigations and also geological mapping in extensive areas. Despite this, one of the most important problems in using obtained data from the surveys is accurate interpretation of the data. Otherwise, there will be no beneficial results while spending high costs. Thus the interpretation of the data is as old as the surveys. Several experts have tried to improve the interpretation of HEM data and they have achieved great successes. Almost the results of all these surveys are presented as resistivity (or conductivity)-depth sections. To reach this target, the first step is to solve the electromagnetic induction integral equation. As solving this integral is not possible using analytical methods, several numerical methods such as Laplace transformation, Hankel transformation and Jacobi-Matrix methods have been suggested for the solution of the integral, and different approaches have been presented with each method by various authorities. One of the most important solution methods is fast Hankel transformation. In this paper, it is attempted to use this method for finally obtaining resistivity-depth sections. For solving the induction equation by this method, we need the kernel function of the integral and weighting coefficients that replace the Bessel function in the integral. For this, first we use the Guptasarma-Singh method. Then results of this method are corrected and evaluated. Then, these results will be analyzed and tested with two synthetic models in addition to presenting the results of inverse modeling. Finally, by adding new parameter named α<sub>0</sub> to induction equation, we will clearly see an improvement in the results of inverse modeling. Meanwhile, the problem of singularity that occurs at high frequencies is almost removed.
<strong> </strong>
Helicopter electromagnetic,Inverse modeling,Mundry’s integral,Improved Mundry’s integral
http://www.gsjournal.ir/article_55453.html
http://www.gsjournal.ir/article_55453_dafeb972dc122c1d9e0c9ad3c5fe3dca.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
The Study of Calcareous Nannofossils Correlation and Foraminifera Planktonic of Gurpi Formation in East of Behbahan
119
126
FA
saeedeh
senemari
Associate Professor, Department of Mining, Imam Khomeini International University, Qazvin, Iran
senemari2004@yahoo.com
L.
Fazli
Department of Geology, Faculty of science, Islamic-Azad University, Damavand, Iran
M.
Omrani
Department of Geology, Faculty of science, Islamic-Azad University, Karaj, Iran
m_amravani@yahoo.com
10.22071/gsj.2010.55455
<span style="font-family: Times New Roman;">Nannofossils and foraminifera planktonic have been short range stratigraphy and spread vast geographical because of that two fossils groups can be used for subdividing biostratigraphy. According to this, and due to the lack of any correlational paleontological study, the nannofossils of Gurpi Formation have been investigated in north of Gachsaran. This formation has been formed of marl. As a result of this study and based on the obtained nannofossils and foraminifera planktonic, the studied section is Late Santonian to Late Maastrichtian in age, that corresponding to CC16-CC26 Zones (Sissingh, 1977) and <em>Dicarinella asymetrica- Globotruncanita elevata</em> Zone to<em>Abathomphalus mayaroensis</em> Zone (James & wind, 1985). </span>
Corrolation,Calcareous Nannofossils,Planktonic Foraminifera,Gurpi Formation,East of Behbahan
http://www.gsjournal.ir/article_55455.html
http://www.gsjournal.ir/article_55455_9954098d7497852075951140babffbba.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Modification of Anbalagan Method for Slide Hazard Zonation in Coastal Desert Area
127
132
FA
M.
Mahdavifar
International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran.
mahdavif@iiees.ac.ir
10.22071/gsj.2010.55457
A new method is developed using modification of Anbalagan method (1992) for slide hazard zonation in coastal desert area. A region in the south of Iran is studied using the method, and the result is compared with the result of zonation using Anbalagan method. This comparison shows that the use of new method can provide better results for slide hazard zonation in coastal desert area in the middle scales.
Hazard zonation,Landslide,Slide,Coastal Desert Area
http://www.gsjournal.ir/article_55457.html
http://www.gsjournal.ir/article_55457_eb1292fa1109030af7ff6570c80cf160.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Petrogenesis of Chah Salar Granitoidic Pluton (SW of Neishabour)
133
150
FA
M.
Sadeghian
دانشکده علومزمین، دانشگاه صنعتی شاهرود، شاهرود، ایران.
m.sadeghian1392@gmail.com
H.
Ghasemi
0000000154469961
دانشکده علومزمین، دانشگاه صنعتی شاهرود، شاهرود، ایران.
h-ghasemi@shahroodut.ac.ir
Z.
Farsi
دانشکده علومزمین، دانشگاه صنعتی شاهرود، شاهرود، ایران.
10.22071/gsj.2010.55458
<span style="font-family: Times New Roman;">Chah Salar granitoidic pluton is located in the N of Chah-Salar village, SW of Neishabour, in the northern margin of structural Central Iran zone. This pluton intruded in Sabzevar ophiolitic Zone and based on the field observations, petrographical and geochemical classification diagrams, its lithological composition composed of diorite, quartzdiorite, granodiorite and alkali feldspar granite. Alkali feldspar granites as a much fractionated end-members of this rock association are intruded in this pluton in the form of dikes or apophyse shapes. Granitic pegmatites and their associated quartzolites are the most differentiated end-member of this rock association. Their subvolcanic equivalents such as pyroxene-bearing andesite, andesite, trachyandesite and dacite cut this pluton in the forms of dikes or domes. The studied rocks show variety of textures including granular, myrmekitic, graphic, porphyritic, microlitic porphyry and pilotaxitic. Except alkali feldspar granites which are highly fractionated, the other lithological compositions, on the variations diagrams of major, trace and rare earth elements versus SiO<sub>2</sub> or differentiation index show continuous compositional variations. This pluton has calc-alkaline and metaluminous nature and belongs to I-type granitoids. Also tectonic setting discrimination diagrams indicate that the Chah Salar granitoidic pluton belongs to volcanic arc granitoids (VAG) and continental arc granitoids (CAG). Detailed investigations of field geology, petrography and geochemical characteristics indicate that magma-forming of this pluton is resulted from partial melting of subducted oceanic slab (metabasite) or metasomatized mantle wedge and then evolved by fractional crystallization, magma contamination or magma mixing. </span>
Petrogenesis,Granitoidic pluton,Continental Arc Granitoids,Fractional Crystallization,Chah Salar,Neishabour
http://www.gsjournal.ir/article_55458.html
http://www.gsjournal.ir/article_55458_764c3fa71cb5d964b60ea10bb03231e5.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Properties of Young Volcanic Rocks in southeast of Bijar
151
156
FA
M. H.
Razavi1
Department of Geology, Tarbiat Moallem University, Tehran, Iran
razavi@saba.tum.ac.ir
A.
Sayyareh
Department of Enviromental Geology, Geological Survey of Iran, Tehran, Iran
sayyareh43@yahoo.com
10.22071/gsj.2010.55463
<span style="font-family: Times New Roman;">In the south of Bijar, north east of Sanandaj in the Kordestan Province, and in the Sanandaj-Sirjan structural zone, young volcanic rocks are present. In this area, rocks with Cretaceous, Oligocene,</span> <span style="font-family: Times New Roman;">Miocene and Pliocene ages are also observed. Based on field observations, volcanic activities occurred during two main stages. In the first stage, eruption of pyroclastic material made a volcanic cone and a crater. In the next stage, lava erupted. Volcanic rocks are a combination of trachy-andesite, andesite, andesite-basalt and basalt. In the magma poor in silica, presence of olivine and analcime and lack of orthopyroxene and pygeonite are the evidence of alkaline type magma series. Petrographical evidences such as the existence of gneiss xenoliths and quartz xenocrysts with reaction rims are the results of contamination processes. In terms of geochemistry, the variations of Rb, Sr, Pb and Hf confirm this phenomenon as well. Based on low topography of volcanic rocks, suture zone, strike-slip faults, and petrologic evidence, low degrees of partial melting in source and crustal contamination in the region, the magmatism occurred in a tensional tectonomagmatic environment. Local tension and opening along the strike-slip fault zone provided a way for ascending of magma to the earth surface.</span>
<span style="font-family: Times New Roman;"> </span>
Bijar,Alkaline Series,Sanandaj-Sirjan,Contamination
http://www.gsjournal.ir/article_55463.html
http://www.gsjournal.ir/article_55463_ae77b7b424207c80e6955f0831c236a7.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Geochemical and Mass Changes at the Sar-Faryab Bauxite Deposit, Kohgeloye and Bovair-Ahmad Province: Using Al, Ti, Zr and Y Geochemical Characteristics
157
164
FA
A.
Zarasvandi
Department of Geology, Faculty of Earth Sciencees, Shahid Chamran University, Ahvaz, Iran
zarasvandi@yahoo.com
H.
Zamanian
Department of Geology, Faculty of Sciencees, Lorestan University, Khoramabad, Iran
hasanzamanian@yahoo.com
E.
Hejazi
Department of Geology, Islamic Azad University, Khoramabad, Iran
A.H.
Mansour
Department of Geology, Faculty of Earth Sciencees, Shahid Chamran University, Ahvaz, Iran
10.22071/gsj.2010.55464
<span style="font-family: Times New Roman;">The Sar-Faryab bauxite deposit is located in 250 km east of Ahvaz city in Kohgeloye and Bovair-Ahmad Province, Iran. Structurally the deposit is located in the Zagros Simply Fold Mountain Belt and was formed between the Ilam and Sarvak Formations. The bauxite horizon in this deposit consists of marly limestone, argillite, oolitic-Pisolitic, yellow, red and white bauxite. This study uses the geochemistry of immobile elements (Al, Ti, Zr and Y) to trace the precursor rock of the bauxite deposit and to calculate the mass changes that took place during weathering and bauxitization. The result indicates that elements are depleted and elements are enriched during the weathering and bauxitization. Geochemical data show that argillaceous debris in the Sarvak limestone can be the source of the Sar-Faryab bauxite deposit.</span>
Geochemical Variations,Bauxite,Sar-Faryab,Mass changes
http://www.gsjournal.ir/article_55464.html
http://www.gsjournal.ir/article_55464_4eafc28f0550faac43efd387cc5d29aa.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Inverse Modeling of Magnetic Data Using Subspace Method
165
174
FA
A.
Nejati Kalateh
Petroleum and Geophysics Engineering, Shahrood University of Technology, Shahrood, Iran
M.
Mirzaei
Science Faculty, Arak University, Arak, Iran
N.
Gouya
Petroleum and Geophysics Engineering, Shahrood University of Technology, Shahrood, Iran
E.
Shahin
Geological Survey of Iran, Tehran, Iran
10.22071/gsj.2010.55466
<span style="font-family: Times New Roman;">In this paper we used orthogonal basis functions and expansion coefficients for inverse modeling of magnetic data. The basis functions chosen are normalized eigenvectors of second derivation of the objective function (Hessian matrix) calculate for an initial model. Limited number of basis vectors obtained in this way defines a new subspace in model parameters space. A new objective function is defined in term of these new parameters and minimized in subspace of original space. As in geophysical inverse problems we need to inverse matrixes that are functions data and geometry of data and model parameters. The matrix inversion in new subspace</span> <span style="font-family: Times New Roman;">of the original space will be better conditions due to less dimensionality in the inversion. Since the most significant eigenvectors corresponding the largest eigen values in Singular Value Decomposition ( SVD) of matrixes. Others eigenvectors have less influence in fitting data or lead inversion procedures to local minima. With apply subspace method inversion will be fast and stable against the noise. The efficiency of the method is tested with synthetic and real magnetic data (acquired from Moghan area, north-west of Iran). The results proved fast convergence and stability of inversion against the noise.</span>
Inverse modeling,Subspace method,Convergence,Matrix Projection,Orthogonal Functions
http://www.gsjournal.ir/article_55466.html
http://www.gsjournal.ir/article_55466_0fba60f512de32f1325a72f89a1f1e4a.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Hydrocarbon Potential Evaluation and Depositional Environment of Sargelu Formation in Masjid-i-Soleiman Oilfield
173
178
FA
B.
Alizadeh
Department of Geology, Earth Science Faculty, Shahid Chamran University, Ahwaz, Iran
alizadeh@scu.ac.ir
S. H.
Hosseini
Department of Geology, Earth Science Faculty, Shahid Chamran University, Ahwaz, Iran
10.22071/gsj.2010.55468
<span style="font-family: Times New Roman;">Sargelu Formation is deeply buried and has limited distribution in Dezful Embayment (limited to the northern part), hence, investigation of petroleum potential of this formation has attracted many petroleum geologists. In this study, hydrocarbon potential of Sargelu Formation in Northern Dezful Embayment is evaluated geochemically. For this purpose 34 drill cuttings from well numbers, 309, 310, 312 and 316 in Masjid-i-Soleiman (MIS) oilfield were selected, and geochemical analyses such as Rock-Eval VI pyrolysis and PY-GC were performed. The results reveal that the formation has “Very Good” hydrocarbon potential because of its high amounts of Total Organic Carbon (TOC). Results were plotted on Van-Krevelen as well as on HI vs. T<sub>max</sub> diagrams, and demonstrated mixed Kerogen Type III and IV due to low HI caused by higher thermal maturity, in well numbers 309, 310 and 312. However, the prominent Kerogen type was determined to be of mixed Kerogen type II and III. In all, the organic matter in well No. 316 has a better Kerogen type (mixed type II and III). All the Samples plotted on Smith Diagram have more than 0.1 S<sub>1</sub>/TOC ratios and capable of generating hydrocarbon. The Pr/nC<sub>17</sub> vs. Ph/nC<sub>18</sub> ratio demonstrates marine environment for Sargelu Formation. Pyro and thermograms reveal that normal alkanes are dominated in C<sub>15</sub> – C<sub>20</sub> range, while heavy normal alkanes are missing due to its high thermal maturity. In all it can be concluded that Sargelu Formation in MIS oilfield, due to its paleoenvironment as well as burial depth exclusively has a good quality of organic matter with adequate maturity at the end of oil window and hence is gas-prone.</span>
Dezful embayment,Masjid-i-Soleiman Oilfield,Sargelu Formation,Genetic Potential,Depositional environment,Rock-Eval,Pyrolysis– Gas Chromatography
http://www.gsjournal.ir/article_55468.html
http://www.gsjournal.ir/article_55468_6c107c8eb0130c993992d2082063e429.pdf
Geological Survey of Iran
Scientific Quarterly Journal of Geosciences
1023-7429
2645-4963
19
75
2010
05
22
Determination of Drilling Point using Fuzzy Logic in GIS Case Study: Now Chun Copper Prospect
179
188
FA
G. R.
Elyasi
Exploration of Mining Engineering Dep., Mining Faculty, Tehran University, Tehran, Iran
ghrelyasi@yahoo.com
M.
Karimi
GIS Department, Survey Faculty, K.N.Toosi University of Technology, Tehran, Iran
A.
Bahroudi
Exploration of Mining Engineering Dep., Mining Faculty, Tehran University, Tehran, Iran
bahroudi@ut.ac.ir
A.
Adeli Sarcheshme
Exploration of Mining Engineering Dep., Mining Faculty, Tehran University, Tehran, Iran
10.22071/gsj.2010.55471
<span style="font-family: Times New Roman;">Piles of maps from different sources with varying scales and formats and different styles and absence of a proper solution for integrating vast amount of information has resulted in a complexity for preparing mineral potential map. Using GIS not only organizes the information related to mineral exploration but also has the ability to produce and integrate information layers in different models with more precision and speed and supports spatial decision makings. In this article mineral potential map of Now Chun copper prospect has been produced for determination of drilling points. Used layers in this study include rock type, structure, alteration, mineralization indicators, anomaly zone of chargeability and apparent resistivity and metal factor, anomaly of copper and molybdenum and Cu-Mo additive indexes. After information preparation, Factor maps were weighted and integrated in the inference network. Integration use of Fuzzy logic and index overlay operators in inference network can eliminate defects in other models and provide more flexible integration of factor maps. Regarding to produce mineral potential map, mineral potential zones of porphyry copper were located in north-east parts of studied area. Eventually, the degree of correlation between mineral potential map and those operated exploration boreholes have been estimated for two different classes, 63.16 % and 64.52 %. Comparison between the high potential points indicated by our mineral potential maps with those previous drilled boreholes reveals about 26% discorrelation. It means that if such present study had been done before any drilling operation, it could have saved 200,000$ just for drilling expenditure. </span>
GIS,Mineral Potential Map,Fuzzy logic,Now Chun
http://www.gsjournal.ir/article_55471.html
http://www.gsjournal.ir/article_55471_85ad6b814965ef14f74846a194772903.pdf