Petroleum geology
Haniyeh Ghayeni; Mohamad Hosein Mahmudy-Gharaie
Abstract
Investigating the hydrocarbon generation potential of the Kazhdumi Formation, as the most important oil source rock in the Zagros sedimentary basin, is of great importance. The expansion of the Kazhdumi Formation in the Zagros Basin has been associated with differences in sedimentation depth of the basin ...
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Investigating the hydrocarbon generation potential of the Kazhdumi Formation, as the most important oil source rock in the Zagros sedimentary basin, is of great importance. The expansion of the Kazhdumi Formation in the Zagros Basin has been associated with differences in sedimentation depth of the basin leading to varieties in sedimentary facies and the organic matter preservations. Five black shale samples from Perchestan and Tang-E Maghar sections were selected for analysis by Rock-Eval pyrolysis, and were compared to the data of 25 Kazhdumi samples from different oil fields of Nowrouz, Soroush, Azadegan and Chah-E Binak, previously studied in the Zagros Basin. Additionally, sedimentary environment and depositional conditions were investigated. Sedimentary and geochemical evidences indicate a dominant condition of high organic content shale deposition in the reducing to semi-oxidative environments. The values obtained for total organic carbon (TOC) ranged from 1.2 to 6.9%. Examination of the thermal maturity of the samples showed a wide range from the immature range to the middle oil window, which are often in the range of type II and III kerogens. Finally, the drawing of the TOC vs. S2 diagram represents the higher hydrocarbon generation potential of the Kazhdumi Formation in the Tang-E Magher section, and the TOC vs. HI diagram shows the greater oil generation in the Soroush field, compared to the other studied areas.
M. A. Oladzad Abbas Abadi; B. Movahed
Abstract
Hydrocarbon potential Evaluation of formations by using ∆logR method (a method based on separation of well logging of porosity DT/CN./RHOB) and resistivity well logging (Rt). This method has been today applied as an appropriate method in many of famous wells of the world. The beginning of these methods ...
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Hydrocarbon potential Evaluation of formations by using ∆logR method (a method based on separation of well logging of porosity DT/CN./RHOB) and resistivity well logging (Rt). This method has been today applied as an appropriate method in many of famous wells of the world. The beginning of these methods drew attention of many researchers in 1980. It had organic matters on the well logging based on the influences of layers containing organic matters. Passey et al. (1990) provided away for predicting of rich of organic material in source rock that have a high accuracy and potential for studying extensive rang of maturity condition. The basis of this method is overlapping porosity well logging (sonic, neutron, density) scaled on the resistivity well logging and determining the degree of separation between these two loges and calculation of total organic carbon TOC and S2. Using this method we can gain appropriate relative evaluation of formations without preparing sample during times of exploration. In this study, the areas which have rich organic matter of Gadvan formation in the SP-A well located in the South Pars Area have been deter mind with use of ∆logR way and for SP-A well, yielding results of this studies was compared with data relating to Rock – Eval Pyrolysis analysis of core samples and was observed good correlation.
A. Rajabi-Harsini; M. Memariani
Abstract
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 ...
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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.
M. Paryab
Abstract
Hydrocarbon source rocks, the subject of various analyses and investigations, are well appreciated because of their capacity for oil generation. In the present study, attempts were made to evaluate source rock using a leap cost analytical method. For this purpose, some samples from these formations were ...
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Hydrocarbon source rocks, the subject of various analyses and investigations, are well appreciated because of their capacity for oil generation. In the present study, attempts were made to evaluate source rock using a leap cost analytical method. For this purpose, some samples from these formations were analyzed by Rock- Eval. CO2 generated from these samples at 350ºС are calculated as mgHy/gr rock or Kg Hy/Ton rock. As this method requires more time and is relatively expensive, we offered a new method in which by calibration of data, obtained from analyzed samples, the result could be attributed to the whole interval of a formation. By calculation of S2, Tmax and TOC of analyzed samples collected from wells A and B for both Pabdeh and Gurpi formations in accordance with ∆LogR method, rescaling of Resistivity-sonic logs, Resistivity-Density logs and Resistivity-Neutron logs, TOC content of these formations were estimated. Comparison between these data and data obtained from direct sample measurements in lab and extrapolation of an equation that relates these data to S2 and TOC of sample analysis, TOC and S2 content of whole intervals of these formations were calculated through ∆LogR method. Then hydrocarbon generation potential of the Pabdeh and Gurpi formations were finally evaluated. These data were processed in a neural network method with forward back propagation capability designed as try and error structure within Matlab software. Final results are in good agreement with those data obtained from direct measurements.
