List of articles (by subject) Geochemistry
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Open Access Article
1 - Genetic classification of the Persian Gulf Eastern part oil fields by infrared spectroscopy of asphaltene samples
Morteza Taherinezhad Morteza Asemani Ahmad reza RabbaniAsphaltene is always considered as a problem in oil industry. But, asphaltenes are desirable compounds in geochemical studies specially in oil-oil correlation. Oil-oil correlation is one of the most important issues in geochemical studies that enables to classify oils g MoreAsphaltene is always considered as a problem in oil industry. But, asphaltenes are desirable compounds in geochemical studies specially in oil-oil correlation. Oil-oil correlation is one of the most important issues in geochemical studies that enables to classify oils genetically. Asphaltenes due to their structural similarity with kerogen and unaffected and/or little affected from secondary processes are known as valuable compounds in geochemical studies. So, in this paper the structural characteristics of asphaltenes were considered as a correlation parameter. For this study 5 oil samples were collected from the Persian Gulf eastern part oil fields. Structural characteristics of these asphaltenes were investigated by Fourier transform infrared (FTIR) spectroscopy. 2D and 3D graphs based on aliphatic and aromatic compounds (predominant compounds in asphaltenes structure) and sulfoxide and carbonyl functional groups (which are represent of sulfur and oxygen abundance in asphaltenes) were used for comparison of asphaltenes structure in different samples. According to the results of these defined graphs, the studied oil samples comprise two oil families with distinct genetic characteristics. The first oil family consists of the Salman and Reshadat oil samples, and the second oil family consists of the Resalat, Siri E and Siri D oil samples. To validation and complement the obtained results, the other common geochemical techniques such as stable carbon isotope and biomarkers parameters, were employed and these techniques completely confirmed previous results. According to biomarker parameters, the first oil family originated from marl source rock and the second oil family was sourced from carbonate source rock. Manuscript profile -
Open Access Article
2 - Origin of seeping hydrocarbon gases from onshore mud volcanoes in Makran coast of Iran
Mahin Farhadian Babadi Behzad Mehrabi Adriano Mazzini Elena Poludetkina Ata ShakeriMud volcanoes are geological structures formed as a result of gas emission, mud-fluid mixing and variably sized rock fragments in onshore and offshore settings. These structures are different morphologically which considered as significant marker of modern crustal movem MoreMud volcanoes are geological structures formed as a result of gas emission, mud-fluid mixing and variably sized rock fragments in onshore and offshore settings. These structures are different morphologically which considered as significant marker of modern crustal movement and neotectonic activity. Occurrence of numerous mud volcanoes on the Makran accretionary prisms in Iran and Pakistan are reported which caused by the convergence of the Arabian and the Eurasian plates. In this study, origin of discharged hydrocarbon gases from three active onshore mud volcanoes; Ain, Borborok and Sand Mirsuban in Makran coasts of Iran were examined. The released gases of all these mud volcanoes are dominantly methane with concentration between 97.24-99.18 vol. % and minor amount of ethane (0.04-1.2 vol.%), propane (0.001-0.194 vol.%), n-butane (226 ppmvol.%), iso-butane (5-363 ppmvol.%), n-pentane (37ppmvol.%), iso-pentane (1-66 ppmvol.%), hexane (1-78 ppmvol.%) and CO2 (0.07-0.4 vol.%). Carbon and hydrogen isotope ratio of methane and its heavier derivatives indicate thermogenic source for emitted gases of all investigated mud volcanoes and evidences of the absence of biodegradation. CO2 with carbon isotope ratio of -11.1 to -14.3‰ is organic in origin. Our research suggests the presence of hydrocarbon system and active source rock in Makran active tectonic area. Although the occurrence of an exploitable gas reservoir in this area has to be confirmed by geophysical measurements, geological survey and structural settings. Manuscript profile -
Open Access Article
3 - Geochemical characterization and evaluation of the hydrocarbon potential of Gurpi in a number of fields Located in North West of Persian Gulf
MohhamadReza Kamali محمود معماریانی Ehsan Hosseni Arezoo KaramiThe results obtained from Rock-Eval pyrolysis and measurement of TOC showe that Gourpi and Pabdeh formations in Binak well show that Source rock does not have the sufficient organic material to produce hydrocarbons. However,Gourpi and Pabdeh in formations Hendijan and MoreThe results obtained from Rock-Eval pyrolysis and measurement of TOC showe that Gourpi and Pabdeh formations in Binak well show that Source rock does not have the sufficient organic material to produce hydrocarbons. However,Gourpi and Pabdeh in formations Hendijan and Doroud wells support the organic material to produce hydrocarbons and are placed in a more appropriate stage in terms of production. Samply from Binak Lack Contamiaton and or staining Lokite Source rock Samples from Hendigan and Doroud wells show contamination and Staining to migration from other interuals. Source rock show type II taype II-III in Binak and which the samples are n ot fully matured (the end of diagenesis) and the Kerogen for Source rock type of in Hendijan and Doroud wells is II and II-III respectively traversing maturing pathway by reaching catagenesis stage and reaching at the beginning of oil generation window. In terms of the type of organic matter, most in studay wells are located in oil zone and the maximum production potential is associated with Doroud well Location so that it could serves as a production source rock. Although, the Hendijan well have high yield potential, due to failure to reach to oil generation window it fails in producing oil. Sedimentation in the Binak well is done quickly and in oxidized condition and OM preserved partially. The Hendijan and Doroud wells show medium sedimentation in restricted condition and quick sedimentation in oxidizing environment respectively indicating Marine depositinal environment Manuscript profile -
Open Access Article
4 - Source rock characterization of the Fahlian, Gadvan, and Surmeh formations in giant Gachsaran oilfield
Majid Safaei-Farouji Hossain Rahimpour-Bonab Buyuk GhorbaniThe aim of this study is geochemical evaluation of the Fahlian, Gadvan, and Surmeh formations as possible source rocks in Gachsaran oil field using Rock-Eval Pyrolysis manner. All of the studied samples possess migration index amounts lower than 1.5 showing indigenous n MoreThe aim of this study is geochemical evaluation of the Fahlian, Gadvan, and Surmeh formations as possible source rocks in Gachsaran oil field using Rock-Eval Pyrolysis manner. All of the studied samples possess migration index amounts lower than 1.5 showing indigenous nature of their hydrocarbons. TOC versus S2 and TOC against S1+S2 diagrams suggest fair hydrocarbon generation potential for the Fahlian and Surmeh formations and fair to good potential for the Gadvan formation. for the Fahlian and Surmeh formations type III kerogen and for the Gadvan formation mixed type II and II-III kerogens were identified. So, the Fahlian and Surmeh formations contain organic matter with terrigenous source (gas prone) and the Gadvan Formation possess both of marine and terrigenous organic matter (oil and gas prone). According to the cross plot of Tmax versus Hydrogen index (HI), the Gurpi formation is capable of mixed gas and oil, and gas generation and the Fahlian and Surmeh formations considered only gas prone formations. In terms of organic facies type, the surmeh, Fahlian, and Gurpi formations located in CD, C and CD, and BC and C zones of jones diagram, respectively. So, the Gadvan formation in compare to the Fahlian formation and the Fahlian formation in compare to the Surmeh formation, deposited under more anoxic conditions. In terms of thermal maturity, All of the Fahlian, Gadvan, and Surmeh formations located in oil window zone, but the Surmeh formation possess higher maturity than the Fahlian formation and the Fahlian formation have highr maturity in compare to the Gadvan formation. Manuscript profile -
Open Access Article
5 - Estimation of oil production, restoration of burial history and thermal maturity using Pyrolysis Rock-Eval data and Arrhenius model in one of the wells of Parsi oilfield
Abuzar Bazvandi Bijan Maleki Saeedeh Senemari parviz armaniInvestigating potential source rocks in oilfields is important. In this study, in addition to evaluating the hydrocarbon potential, the Arrhenius kinetic model was used to more accurately assess the source rock maturity status as well as the percentage of oil generation MoreInvestigating potential source rocks in oilfields is important. In this study, in addition to evaluating the hydrocarbon potential, the Arrhenius kinetic model was used to more accurately assess the source rock maturity status as well as the percentage of oil generation in the Parsi oilfield. In the Arrhenius model, the rate of kerogen decomposition is very important. In this research, some source rocks that have been tested by thermal pyrolysis were kinetically analyzed and the source rock conversion ratio (TR) was determined. Based on the results of burial history and thermal modeling, it was found that Kazhdumi and Pabdeh formations were in the oil window well while Gurpi formation did not enter the oil window due to poor organic matter content (TR = 0). Therefore, among the Kazhdomi, Gurpi and Pabdeh formations in the Parsi oilfield, Kazhdumi formation is considered as the main and most effective source rock of this oilfield with high TTI and TR = 100. Manuscript profile -
Open Access Article
6 - Geochemical Study and Genetic Classification of Fahlian Reservoir Oil Using Infrared Spectroscopy in the Fields of Southwestern Iran
Mohammad Ali Sahmoradi Mohammad Hossein Saberi Bahman Zare nejad Ali ChehraziThe first step in performing geochemical adaptations is to identify the molecular and hybrid structure of the oil. One way to match the use of infrared spectroscopy is to identify and compare the structure of oil samples. Infrared spectroscopy is a practical method with MoreThe first step in performing geochemical adaptations is to identify the molecular and hybrid structure of the oil. One way to match the use of infrared spectroscopy is to identify and compare the structure of oil samples. Infrared spectroscopy is a practical method with easy, low-cost interpretation and reliable results for determining the structure of organic compounds. Also, considering the significant growth of the tendency to develop fast, accurate and reliable analytical methods for industrial applications and also the discovery of new hydrocarbon resources in the sedimentary basin of Abadan plain such as Darkhoein and Yadavaran oil fields in recent years, indicates the need for more comprehensive studies. There is a sedimentary basin in this basin. Based on this, 15 samples of crude oil from Fahlian reservoir were selected and examined in the most important oil fields of this basin, namely Darkhoein (9 samples) and Yadavaran (6 samples) located in southwestern Iran. By dividing the samples by evaluating the crude oil, different analytical goals were achieved. Using infrared spectroscopy, the functional groups in the samples were determined and then the amount of these compounds in different samples was compared with each other. Based on the results of the mass spectrometer, the oils studied in this basin are divided into three families with different genetic characteristics. In this study, it was shown that infrared spectrometer is a fast, reliable and non-destructive analytical option and a complementary or even alternative method of chromatography and biomarkers analysis to perform various scientific and industrial purposes in the oil industry, including quality measurement, Quantity and geochemical evaluation of oil. Manuscript profile -
Open Access Article
7 - Investigation of petrographical and geochemical characteristics of carbonate deposits of the Jamal Formation in the Chah-Riseh section, northeast of Isfahan
Behrad Zebhi Kamand محمد علی صالحی Ezat Heydari Ali BahramiThe Middle Permian Jamal Formation have been investigated for sedimentological and geochemical aspects in the Chah-Riseh section, northeast Isfahan. According to the field studies the Jamal Formation with 251 m thickness divided into eight lithostratigraphic unit. Lower MoreThe Middle Permian Jamal Formation have been investigated for sedimentological and geochemical aspects in the Chah-Riseh section, northeast Isfahan. According to the field studies the Jamal Formation with 251 m thickness divided into eight lithostratigraphic unit. Lower boundary of this formation with an unconformity is underlained by the Sardar Formation which belongs to the Carboniferous period and upper boundary with an unconformity reaches to the Lower Triassic Sorkh-Shale Formation. Facies and microfacies studies of the Jamal Formation led to the identification of two petrofacies and 14 carbonate microfacies. According to the recognized carbonate allochems, petrofacies and microfacies of the Jamal Formation and some evidence such as transitional microfacies changes, we can consider a depositional environment of a shallow mixed siliciclastic-carbonate ramp platform. Petrographically, four types of dolomites are recognized in the Jamal Formation. The dolomitization model for the type I dolomite is considered forming in tidal flat and burial dolomitization for types II, III and IV. Geochemical studies including major and trace elements analysis comprised of elements such as Ca, Mg, Sr, Mn and Fe. Using ratios of the elements and also by plotting some of these elements cross carbon and oxygen isotopes in various diagrams have been used in determining the original mineralogy of carbonate deposits and efficient diagenetic system on the Jamal Formation. The results indicate that the dominant diagenetic environment effected on the carbonate deposits of Jamal Formation was occurred in a semi-closed system and the original mineralogy was aragonite. Evaluation of major and trace elements contents of the four types dolomites, confirmed different characteristics of theses dolomite resembling crystal sizes in petrographic studies. Carbon and oxygen isotopes data of dolomites also defined their diagenetic situations. Manuscript profile