List of Articles Geochemistry

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  1 - Investigation of Garue Shale as an Unconventional Hydrocarbon Reservoir
  امینه لطفی یار علی چهرازی نادر  ثابتی
  20.1001.1.22518738.1393.3.7.5.3
  Abstract Nowadays because of the increase in both price and demand for fossil fuel, the unconventional resources are becoming more important in most countries. Gas shale is one of the important unconventional reserves. Gas shale is fine grain rocks, and has economic More

  Abstract Nowadays because of the increase in both price and demand for fossil fuel, the unconventional resources are becoming more important in most countries. Gas shale is one of the important unconventional reserves. Gas shale is fine grain rocks, and has economic gas reserves. Gas shale formations have very low porosity and for have, economic production fracturing is essential. In this study, investigate Garue formation shales in Lorestan district (case study of Babaghir 1 well-cutting samples) as unconventional reservoir. Garue formation is consisting of alternation of black clay limestons bearing radiolar and blackbituminousshale bearing.Plankton and radiolars show deep marine basin, and microfossils show thatGarue formation age is Neocomian to Knyasyn. Geochemical data show that Garue shale formation is good quality (profit area of Toc). In addition, kerogen in Garue shale formation is type III, and show gas sources rock for Garaue shale. In addition, this data confirm deep marine facies for Garue formation. Mineralogy studies show that, Garu formation consist of the clay content less than 4% (4-3%), and the brittleness index is sutable. Manuscript profile
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  2 - Geochemical study of Tar-mat formation in Bangestan reservoir in Kupal oil field
   
  20.1001.1.22518738.1394.5.10.1.5
  Kupal anticline is elongated and almost symmetric. This structure is located in Northwest of Ahwaz city and consists of two reservoir including Bangestan and Asmari. Kazhdumi, Pabdeh and Gurpi formations are probable source rocks and Gachsaran Formation constitutes the More

  Kupal anticline is elongated and almost symmetric. This structure is located in Northwest of Ahwaz city and consists of two reservoir including Bangestan and Asmari. Kazhdumi, Pabdeh and Gurpi formations are probable source rocks and Gachsaran Formation constitutes the cap rock. Because project topic is defined on Bangestan Group, so reservoir studies of Bangestan is focused on Sarvak Formation. Rock-Eval and geochemical analyses conducted on source rocks indicated that Pabdeh Formation is at early stage of oil generation window in the Kupal oil field. Kazhdumi Formation has not been drilled at this field, so geochemical and maturity assessment of this formation has been evaluated using samples from adjacent oil fields including Marun and Haftgel. Geochemical analyses indicated that Kazhdumi Formation is mature enough and is considered to be the main source rock. The aim of this project is investigating Tar-mat in Bangestan reservoir in Kupal field. It is thought that Tar-mat layer was formed in vicinity of oil-water contact and can be related to processes including natural deasphaltening, gravity segregation and oil-mixing. Based on Rock-Eval pyrolysis, pyrolysis-GC performed on Sarvak oil, it is suggested primary asphaltene formed from source rock does not exist in the studied oil but it is derived from secondary asphaltene by chemical reactions occurring due to oil-mixing in production well. In addition, analysis performed on asphaltene in oil zone, oil-water contact and water zone suggest that Tar-mat was formed in oil water contact region due to oxidation process. This layer acts as impermeable seal and prevents water flow to oil Manuscript profile
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  3 - 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 Bahrami
  10.52547/ispg.39691.11.21.54
  20.1001.1.22518738.1400.11.21.4.2
  The 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 More

  The 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