Iranian Journal of Earth SciencesHydrocarbon Source Rock Potential of the Late Paleocene Patala Formation, Kohat Basin, PakistanVolume 16 (2024)Issue 2, April 202420240807Hydrocarbon Source Rock Potential of the Late Paleocene Patala Formation, Kohat Basin, Pakistan10.57647/j.ijes.2024.1602.07ENTausifJavedDepartment of Geology, University of Malakand, Chakdara, Dir (Lower), Pakistan
Department of Earth Science, Quaid-e-Azam University Islamabad, PakistanSyedMamoon SiyarDepartment of Geology, University of Malakand, Chakdara, Dir (Lower), Pakistan
Department of Geology, University of Peshawar, Pakistan
SyedMuhammad Wasim SajjadDepartment of Geology, University of Malakand, Chakdara, Dir (Lower), Pakistan
Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Italy
0000-0002-1301-5274FayazAliDepartment of Geology, University of Peshawar, PakistanFawadRaziqDepartment of Geology, University of Malakand, Chakdara, Dir (Lower), PakistanSaeedUllah ShahDepartment of Geology, University of Malakand, Chakdara, Dir (Lower), PakistanNasarKhanDepartment of Geology, University of Malakand, Chakdara, Dir (Lower), Pakistan0000-0002-4895-6269IzazAliDepartment of Geology, University of Malakand, Chakdara, Dir (Lower), PakistanJournal Article20240807The Late Paleocene Patala Formation shales exposed at Tarkhobi Nala, Kohat Basin, Pakistan were geochemically studied in detail for hydrocarbon evaluation. A total of 09 shale samples of the studied formation were analyzed in G & R Labs, Oil & Gas Development Company Limited (OGDCL), Islamabad, Pakistan for TOC and Rock-Eval pyrolysis. The TOC results were low ranging from 0.36 wt. % to 1.25 wt. % indicating poor to fair petroleum potential except a sample falling in the good source rock category. The generating potential values (< 2 mg HC/ g. rock) also show poor ability for hydrocarbon production. The different cross plots between Rock-Eval pyrolysis parameters (HI vs OI; HI vs Tmax; S2 vs TOC) were used to describe the types of kerogen and thermal maturity of the evaluated samples. All these plots confirmed the presence of type IV kerogen which has no capability to generate hydrocarbon except minor gas upon thermal maturation. The thermal maturity of the organic matter was assessed by Tmax (444 °C to 459 °C) which shows that the studied formation is falling in the oil window but due to the presence of type IV (oxidized & reworked) organic matter not able to generate commercial hydrocarbons. Iranian Journal of Earth SciencesA systematic approach for planning a Geochemical survey for Hydrocarbon exploration: An overviewVolume 16 (2024)Issue 2, April 202420240807A systematic approach for planning a Geochemical survey for Hydrocarbon exploration: An overview10.57647/j.ijes.2024.1602.08ENRahulKumar SinghDepartment of Petroleum Engineering and Earth Sciences, Energy Cluster, University of Petroleum and Energy Studies, Dehradun, Uttarakhand, India0000-0002-3663-3729AtulKumar PatidarDepartment of Petroleum Engineering and Earth Sciences, Energy Cluster, University of Petroleum and Energy Studies, Dehradun, Uttarakhand, India0000-0001-7203-0063Journal Article20240807Exploration of oil and gas seepages employing geochemical techniques has helped to discover new hydrocarbon resources across the world. Oil and gas exploration techniques had substantial advancements in the late 2000s. Numerous geophysical and geochemical techniques have been created and are constantly improving along with the advancement of digital technologies. Geochemical techniques are being used with remarkable success in the hydrocarbon exploration business to take informed decisions on project viability. These techniques contributed to determining the different hydrocarbon types, the degree of basin maturity, and the reliability of other petroleum system components. Combining precise geological and geophysical techniques with geochemical approaches can considerably improve the prospect chance of success. The current study offers a thorough discussion of geochemical exploration methodology and recommends an appropriate design process for geochemical surveys. It presents a methodical overview of various survey types as well as the advantages and disadvantages of geochemical techniques in comparison to other techniques used in hydrocarbon exploration.Iranian Journal of Earth SciencesAnisotropic permeability evolution of high void ratio soil under static compression (a case study on clayey loess soil)Volume 16 (2024)Issue 2, April 202420240807Anisotropic permeability evolution of high void ratio soil under static compression (a case study on clayey loess soil)10.57647/j.ijes.2024.1602.09ENGholamrezaShoaeiDepartment of Engineering Geology, Faculty of Basic Sciences, Tarbiat Modares University, Tehran, Iran0000-0001-8506-3331MasoudEnayatDepartment of Engineering Geology, Faculty of Basic Sciences, Tarbiat Modares University, Tehran, IranMohamadReza NikudelDepartment of Engineering Geology, Faculty of Basic Sciences, Tarbiat Modares University, Tehran, Iran0000-0003-4795-0655Journal Article20240807Decreasing the void ratio of soil due to static compression causes soil structure changes and developing anisotropic structure. This phenomenon as a common result causes the development of anisotropic permeability ratio (kh/kv or rk). When the soil shows a high void ratio, it generally contains macropores that have the most effect on the permeability, soil structure changes, and rk evolution during compression. Thus, in this research, two high void ratio samples of clayey loess soil with a granular structure (containing macropores) were prepared to investigate the rk evolutions during one-dimensionally static compression. So, horizontal and vertical permeability of samples were measured at each new void ratio, from high to low values. The tests implemented by a 3D permeameter apparatus that was designed for this research. This apparatus was equipped with a camera to study the soil macrostructure changes during tests. The results show that rk have different trends during compression, so, three stages of permeability anisotropy variations recognized as A, B and C. At high void ratios (stage A), the connected macropores produce high pseudo anisotropic permeability that rapidly decreased during compression. At low void ratios, rk increased due to particle orientation. The Stage B that has minimal values of rk with low variations is the transition stage from A to C stage.Iranian Journal of Earth SciencesCalcareous nannofossil biostratigraphy and paleoecolgy of the Rupelian-Chattian stages (Oligocene) in the Central Iran basinVolume 16 (2024)Issue 2, April 202420240807Calcareous nannofossil biostratigraphy and paleoecolgy of the Rupelian-Chattian stages (Oligocene) in the Central Iran basin10.57647/j.ijes.2024.1602.10ENMohammadShahmoradi FahrejiDepartment of Geology, Shiraz Branch, Islamic Azad University, Shiraz, IranMassihAfghahDepartment of Geology, Shiraz Branch, Islamic Azad University, Shiraz, Iran0000-0001-8155-087XMarziyehNotghi MoghaddamDepartment of Geology, Payame Noor University, Tehran, Iran0000-0001-6542-4101KourosYazdjardiDepartment of Geology, Shiraz Branch, Islamic Azad University, Shiraz, Iran0000-0002-4490-527XBitaMostafaviDepartment of Geology, Shiraz Branch, Islamic Azad University, Shiraz, IranJournal Article20240807Calcareous nannofossils are one group of microfossils that use in biostratigraphy studies since the 1950’s and 1960’s. Recently, because of the potential of nannofossil species for age determination, several authors use this fossil-group in the study of Cenozoic sediments and rocks. Here, we present a nannofossil biozonation based on biostratigraphic information from the Sabzevaran section (Central Iran). The Sabzevaran section mainly consists of marl, limestone, and shaly limestone. Based on index nannofossil species, three nanno-bizones (NP23-NP25) were recognized in this section. According to the identified biozones, the age of the studied deposits in the Sabzevaran section is middle to late Oligocene (Rupelian to Chattian stages). In this section, calcareous nannofossils abundance and diversity are medium to low with a sharp decrease slightly near the conglomerate and sandstone layers and are absence in conglomerate and sandstone beds. Paleoecological data indicate the shallow marine, low latitude and low productivity for the marine deposits of Sabzevaran section. Iranian Journal of Earth SciencesMicrofacies, sedimentary environment and sequence stratigraphy of Asmari Formation in North Western of Charam, Kohgilooyeh and Boyer Ahmad Province, IranVolume 16 (2024)Issue 2, April 202420240807Microfacies, sedimentary environment and sequence stratigraphy of Asmari Formation in North Western of Charam, Kohgilooyeh and Boyer Ahmad Province, Iran10.57647/j.ijes.2024.1602.11ENBehzadSaeedi RazaviConstruction and Minerals Research Group, Technology and Engineering Research Center, Standard Research Institute (SRI), Karaj, Iran0000-0001-8306-5253SaeedehSenemariDepartment of Mining, Imam Khomeini International University, Qazvin, Iran0000-0002-2326-248XJournal Article20240807The Asmari Formation is a thick carbonate sequence in the foreland Zagros Basin that was deposited during the Early Oligocene-Miocene. The Asmari Formation in North Western of Charam, Kohgilooyeh and Boyer Ahmad province was studied in terms of microfacies, sedimentary environment, and sequence stratigraphy. The upper boundary of the section is overlain by the Gachsaran Formation and lower boundary is overlain by the Pabdeh Formation. The studied section consists of limestone, marly limestone, shaly limestone, and intercalated of limestone, shaly and marl. Eighteen microfacies have been recognized. The study of allochemical, terrigenous, and orthochemical elements, Infers that the different sedimentary sub-environments tidal flat, lagoon, barrier, and open marine for Asmari Formation. The Asmari Formation was deposited in on a ramp-type carbonate platform. Three complete sedimentary sequences and one incomplete sedimentary sequence were recognized.Iranian Journal of Earth SciencesEvaluation of the ability of rock (soft) dispersion at the basement of the Darbandikhan Dam’s reservoir, NE Iraq, with a new investigation and Crumb testVolume 16 (2024)Issue 2, April 202420240807Evaluation of the ability of rock (soft) dispersion at the basement of the Darbandikhan Dam’s reservoir, NE Iraq, with a new investigation and Crumb test10.57647/j.ijes.2024.1602.12ENMohammadFathollahyDepartment of Earth sciences, Faculty of sciences, university of Kurdistan, Sanandaj, Iran0000-0002-8787-2658HosseinAziziDepartment of Mining, Faculty of Engineering, University of Kurdistan, Sanandaj, Iran0000-0001-5686-4340BaktiyarMohammed Abdulrahman Al-TaeshiDepartment of Earth sciences, Faculty of sciences, university of Kurdistan, Sanandaj, Iran0009-0009-0078-6297Journal Article20240807The Darbandikhan Dam reservoir in NE Iraq is located on soft sedimentary rocks which sporadically were affected by erosion. The basement rocks include sandstone, siltstone, and claystone, and mineralogically comprise quartz, and feldspar with some lithic fragments that are distributed in a soft matrix. The scanning electron microscope (SEM) images show sheet layers with clay structures for the matrix which is confirm by Semi-quantitative analyses of the EDAX data. The results demonstrate that samples categorize as dispersive soil based on the crumb test (ASTM D 6572–21). The Crumb tests were done in six hours, and the short duration can be considered as a defect. In this research the test time was extended and the behavior of the samples was investigated up to 7 days in intervals of two minutes, one hour, 6, 24, 72 hours, and 7 days. The results indicated that some samples which didn’t show any sign of dispersion in standard duration underwent some kind of egg-shaped erosion after 72 hours, which completely were separated in 7 days, so it would perhaps be better to make modifications to the crumb test. Correspondingly, the Sodium Absorption Ratio (SAR) and Exchangeable Sodium Percentage (ESP) results of soft grain units demonstrated that these units are mainly dispersive.