bluuebunny/crossref_metadata_2025_split huggingface dataset:
Major structural unconformities across Malaysia: geodynamics and basin development of Lawin, Perak
Authors: Mahmud Noor Liana , Sautter Benjamin 
Published: April 2022

Abstract
The first deposits overlying an unconformity may give important insights on the tectonic vertical motions and erosion processes that erased previous records. The Early Cenozoic Deposits in Peninsular Malaysia are reported to be isolated and lie unconformably on Paleozoic basement rocks. Denudation pulses from the Late Cretaceous to Eocene left the Cenozoic deposits in scarce. Stratigraphic and sedimentology studies were restricted to the availability of the resources. This study aims at providing information on the development of the early deposits from a structural perspective with the emphasis on source to sink dynamics. We interpreted the structural settings of Lawin using Digital Elevation Model (DEM) data and satellite images. Structural interpretations were cross-checked with published studies. Field observations were conducted and have been assessed through chemical and petrographic analyses. Evidence of compression and shearing are found to support interpretation. We learned that Lawin had experienced a compression and stages of extensions in its history and developed during extension. Lawin is associated to a major fault that reactivated several times, and from XRD analysis, we have illite-mica which has a close-relationship to a frequent tectonic activities and kaolinite is due to weathering. Petrography analysis were performed from SEM images and thin sections to support minerals found. Evidence of mineral fragments, iron-rich sedimentation and clay fillings were common with few kaolinite pouches. Sedimentology studies were modelled as alluvial fans. Based on DEM analysis, two different lobes are observed and on outcrop, two different angles of tilted bedding between the two lobes were measured, thus we modelled them as incised alluvial fans where the recent fan we see on DEM has extended further from abandoned lobe. Due to its tilting towards the west, we modelled them following an extensional regime.
The brittleness and ductility of shale from Setap shale, Miri, Sarawak
Authors: Baharizan Fatimah Zahrah , Ismail Mohd. Suhaili 
Published: April 2022

Abstract
The brittleness and ductility of Setap Shale from Bekenu, Beluru and Long Lama area can be shown by analyzing the relationship between Poisson’s Ratio and Young’s Modulus. Both Young’s Modulus and Poisson’s Ratio can be calculated using P-wave and Swave value from ultrasonic velocity test. Ultrasonic velocity analysis on core samples from Bekenu, Beluru and Long Lama shows typical values of Poisson’s ratio and static Young’s Modulus of shale. The mineral composition of samples was analyzed using X-ray diffraction (XRD). Beluru 3 was described as marl samples shows significant number of quartz and dolomite which increase the density of the rock higher than Bekenu and Long Lama area. In the other hand, the Long Lama-5 sample shows high ductility compares to other location due to high clay constituents. High clay constituents can be defined by clay constituents greater than 40% composition. The shale with more than 40% are “true shale” where it may affect the conductivity of hydraulic fracturing phase due to high ductility. High ductile shale has the ability to re-seal the fracture due to high elastic material content. The brittleness of shale shows strong relationship between the mineralogical composition of the shale at different locality of Setap Shale and its elastic properties as different samples show different mineral composition.
Potential stratigraphic traps delineation utilizing the spectral decomposition approach for RGB color blending attribute generation: a case study in the Malay Basin
Authors: Al-Masgari Abd Al-Salam , Elsaadany Mohamed , Siddiqui Numair A. , Latiff Abdul Halim Abdul , Abubakar Azli , Imran Qazi Sohai , Babikir Ismailalwali , Khan Muhammad , Adeleke Teslim 
Published: April 2022

Abstract
Implementing the RGB color blending attribute of the decomposed spectral has been successfully conducted for delineating the potential stratigraphic traps within the geomorphological elements of the studied interval from -1253ms to -800ms. The investigated area is situated in the peninsular Malaysia-Malay Basin and covering two neighbouring fields (Inas and Melor). Several fluvial system deposits dominate the studied interval. These interval’s time slices maps reveal several geomorphological features such as low meandering and superimposed fluvial channels system. Moreover, several structural elements and seismic artefacts are also delineated within the depositional sequences (DS-01-02) of Inas and Melor fields. The channel's sinuosity degree reflects the slope ratio of the substratum during the river's lifetime along the channel pathways. However, the low sinuosity of the main channel reflects the higher slope of the bedrock, while the high sinuousness of channels implies a lower depositional substratum slope. Validation steps have been performed utilized the gamma-ray logs signatures from several wells.
Petrophysical evaluation of Kati Formation at Seri Iskandar area, Perak, Malaysia
Authors: Salim Ahmed Mohamed Ahmed , Noh Khairul Arifin Bin Mohd , Sahari Sufizikri Bin 
Published: April 2022

Abstract
Non-linear relationships for shale volume estimation are designed for a specific area or formation age and most of the time they are optimistic in calculating low shale volume. This study evaluates some petrophysical properties of Late Paleozoic Kati Formation in Seri Iskandar area based on well logs and core plug samples from well CTW-01 drilled within University Teknologi PETRONAS campus. Shale volume is calculated using gamma ray log and calibrated with that obtained by sedimentation method in the lab. Porosity is determined from sonic log and calibrated with that measured in lab using Helium Porosimeter on core plugs. The shale volume equation derived from the lab analysis and well log data is Vsh = 1.0157 (IGR) - 0.0158 and achieved a correlation coefficient, R2, greater than 0.99. Shale volumes estimated from GR log using this model are in good agreement with laboratory measurements. Since the porosity is ranging between 0.5% and 2%, the reservoir rocks of the study interval are classified as tight sandstones.
Estimation of porosity from well logs and seismic using artificial neural network
Authors: Yazmyradova Gulbahar , Hermana Maman , Soleimani Hassan 
Published: April 2022

Abstract
The Artificial Neural Network (ANN) is widely used to map and estimate reservoir properties. Since ANN has the ability of non-linear computing and self-error correction, it serves as an alternative method to enhance reservoir characterization by improving reservoir properties' prediction. This study employed an integrated approach where seismic, and well log data are used alongside ANN to evaluate petrophysical properties in Field X, South Caspian Basin. The study field is situated in the South Caspian Basin, which developed during Tertiary-Quaternary. The South Caspian Basin covers the southern part of the Caspian Basin, coastal regions of eastern Azerbaijan, northern Iran, and western Turkmenistan. The field is geologically situated on an elongated and multi-crest, anticlinal feature, better known as Apsheron Sill. Available data set consists of log data from four wells: X1, X2, X3, X4, and 3D pre-stack seismic data. Firstly, the reservoir properties were calculated from the well log data. The simultaneous inversion was carried out to obtain elastic rock properties like the P-impedance, S-impedance, density. After that, elastic properties were used to obtain 3D dimensional SQp and SQs attributes. Furthermore, the Radial basis function Neural Network (RBFN) model was created with optional inputs: volume of P-impedance, S-impedance, density, SQp, SQs and property logs and outputs: porosity. Moreover, this research work demonstrates an application of SQp and SQs attributes for properties prediction using neural network. The neural network's primary purpose is to determine a relationship between obtained volumes and reservoir parameters, porosity at well locations. The RBFN model is successfully trained and validated on the field data. The results demonstrated an excellent correlation between actual property logs. They predicted properties, which gives confidence for spatial prediction in areas where well logs are not available.
Performance Evaluation of 1-Butyl-3-Methylimidazolium Chloride as Shale Swelling Inhibitor
Authors: Rahman Tauhidur , Negash Berihun Mamo , Moniruzzaman Muhammad , Padmanabhan Eswaran , Ato Quainoo Kwamena 
Published: April 2022

Abstract
Shale instability due to hydration and swelling is an unavoidable problem during hydraulic fracturing or drilling with water-based fluids. In this study, 1-butyl-3-methylimidazolium chloride (BMIMCl) an ionic liquid was utilized as a clay swelling inhibitor. The performance of BMIMCl was evaluated by the bentonite plate soaking test and linear swelling test. FT-IR and zeta potential test was done to explain the swelling inhibition mechanisms. Moreover, XRD test was conducted for the characterization of bentonite (swelling clay). 2 wt.% BMIMCl reduced the swelling rate of bentonite by 19.38% while the conventional and mostly used inhibitor, 3 wt.% KCl reduced 13.84% compared with distilled water. These results showed that BMIMCl has better inhibitive properties than the most used clay stabilizer, KCl. This inhibitor showed better performance because of the presence of a hydrophilic head and hydrophobic tail in its structure. The hydrophilic positive head helped it to get adsorbed on the bentonite surface, forming hydrogen bonds, and reduced the surface negative charge. On the other side, the butyl chain may be made a hydrophobic shield that prevented water from entering into the interlayer space. The ability of BMIMCl to form bonds with bentonite and water was confirmed by FT-IR analysis. Therefore, BMIMCl has the potential to be an effective shale swelling inhibitor during drilling and hydraulic fracturing operations in the water-sensitive shale formation.
Boundaries and lithofacies of the Kati Formation (SW Perak, Peninsular Malaysia)
Authors: Khan Muhammad Ekrahm Nawas , Vintaned Jose Antonio Gamez 
Published: April 2022

Abstract
Very few geological research has been undergone on the Kati formation due to its scarcity of natural outcrops and complexity. The heavily weathered and limited number of natural outcrops available around the areas of Bandar Seri Iskandar and Parit (Perak) may help to define the Kati Formation in a more clear way. After recent human construction activities, more exposures can be studied, which makes easier the process of gathering geological information. The Kati Formation inspires quite a few questions to the scientific community, such as the source of the iron oxide extensively found on it and the processes that turned a softer shale into hard concretions, the presence of trace fossils as the only palaeontological evidences preserved in this heavily replaced rock unit, and the age of the overlying quaternary deposits, which is a key for understanding, in turn, the succeeding diagenetic processes. The objective of this research is to better define the Kati Formation in relationship to their associated quaternary materials, Mesozoic granites and metamorphic rocks, all by using classical stratigraphic methods first.
Evaluation of N-ethyl perfluorooctyl sulfonamide as a thickener of supercritical carbon dioxide
Authors: Mojid Muhammed Rashik , Negash Berihun Mamo , Babatunde Kawthar A , Jufar Shiferaw Regassa 
Published: April 2022

Abstract
Usage of supercritical CO2 (Sc-CO2) as fracturing and displacing fluid is given much attention in recent years. It enables the prevention of issues related to hydraulic fracturing such as formation damage, clay swelling, capillary trapping, and consumption of a high volume of water. However, the low proppant carrying capacity, high frictional resistance, and fast filtration of Sc-CO2 are the challenges that require further research. Characterization of shale samples for implementation of Sc-CO2 as a fracturing fluid consists of imaging and qualitative analysis, identification of crystalline phases presents in material and determination of pore size distribution, surface area, micropore volume, porosity, and matrix density. Shale samples from Eagle Ford (EF-1. EF-2), Mancos (MC), and Wolfcamp (WF) shale formations have been characterized using field-emission scanning electron microscope (FESEM), X-Ray diffraction (XRD), surface area analyzer and porosimetry system (SAP) and Helium Porosimeter. From FESEM and EDX experiment, among all the samples, EF-1 has the highest carbon content (25.97%), EF-2 is mostly calcium dominant (33.17%) and WF has quartz having the presence of 3.37% of silicon. The existence of these elements and compounds are also validated by the qualitative and quantitative analysis of the XRD patterns. FESEM estimates that all these shale samples have the presence of mostly mesopores. Results from SAP experiment show that BJH adsorption average pore diameter of EF-1, MC and WF 30.8490, 8.5128, and 26.4318 nm respectively and it validates FESEM result. In terms of porosity, MC has the highest (7.4%), while EF-1 has the lowest (2.01%). For eradicating the problem of low proppant carrying capacity of Sc-CO2, thickening agents such as N-ethyl perfluorooctyl sulfonamide, a viscoelastic surfactant (VES) is used in this study. The molecular simulation study of N-ethyl perfluorooctyl sulfonamide to Sc-CO2 increases the viscosity of Sc-CO2.170 times than the actual viscosity of Sc-CO2. Although this an excellent result to derive yet the experimental validation of this result is needed to pave its implementation on real field scenarios.
Major, trace, and rare earth element geochemistry of black shales from Devonian Sanai Formation in Northwestern Peninsula Malaysia: implications for the depositional environment, provenance, and tectonic setting
Authors: Ibad Syed Muhammad , Padmanabhan E. 
Published: April 2022

Abstract
In this study major, trace, and rare earth elements (REEs) content of Sanai (SA) shales were determined by XRF-ICP-OES and ICP-MS. These results were used to probe tectonic setting, depositional environment, and provenance and of the SA Formation black shale. These black shales contain an average total organic carbon (TOC) content of 2.68 wt. %. Black shales from SA formation were deposited in the active continental margin based on ternary diagrams of La–Th–Sc and Th–Sc–Zr/10. SiO2 is rich in SA shales with avg. 59.5% while Al2O3 is the second most dominant major oxides with avg. 15.8%. Major oxides of the Western Peninsula (WP) Malaysia shale and hot shale gas reservoirs from China are also compared for the assessment. Redox element ratios infer deposition of the black shale most likely occurred in oxic to the anoxic environment. SA Formation black shales show a low Sr/Ba (< 0.5) value, indicating low salinity during the deposition. Geochemistry results indicate that the SA black shales seem to have been originated principally from the felsic source rock which might be granite in this case.
The potential of shale gas resources in Peninsular Malaysia
Authors: Owusu Esther B. , Gebretsadik Haylay Tsegab 
Published: April 2022

Abstract
Even though the black shales in Peninsular Malaysia covered a quarter of the total surface area and have been overlooked for their economic potential except few workers have evaluated their thermal maturity using rock-eval pyrolysis, vitrinite reflectance analysis and illite crystallinity. According to these research works, the shales have been categorized into immature, mature and overmatured successions, which in turn dictated the exploration activities of commercially viable shale gas in the onshore Peninsular Malaysia. In this work, published and unpublished data on the scattered black shales of Peninsular Malaysia were examined to assess exploration potential of shales from various stratigraphic windows. Thus, using comparative evaluation of all the thermal history plots of the black shales from Peninsular Malaysia; areas of thermally matured source rocks are identified. According to the thermal maturation assessment; the Palaeozoic black shales in the Peninsular Malaysia have minimal generative potential for economically viable source rock for hydrocarbon, whereas the younger successions of Oligocene to Miocene have considerable potential to serve as source rocks of feasible prospect, provided permissible geological settings are met.
Organic geochemical characterization of Cretaceous — Eocene shale and mudstone in Belaga Formation
Authors: Ibrahim Walaa Elnasir , Salim Ahmed Mohamed Ahmed 
Published: April 2022

Abstract
Sarawak Basin has been very prominence for increasing hydrocarbon potential in their formations and its nature as a source rock. Previous studies highlighting more on the evaluation of geochemical characteristics of Paleogene-Neogene coals as the source rock without taking into consideration shales and mudstones in the area. The targets of the study are to evaluate the potentiality of the hydrocarbons, the type of organic matter and thermal maturity of shales and mudstones of Belaga Formation, mainly by using data of Rock-Eval pyrolysis and vitrinite reflectance data. Twenty-one outcrops with twenty-nine samples from Belaga Formation shales and mudstones in the Central Sarawak Basin were analyzed by means of geochemical techniques. The shales and mudstones samples of the Belga Formation has low value of S2 ranging between 0.02-0.66 mg HC/g rock with an average 0.09 mg HC/g rock, indicating that the formation has poor hydrocarbon generative potential. There is lack of hydrogen-rich in the organic matter content in the Formation samples, that were affect the quality of source rocks to be evaluated as good source rock. Geochemical data (Rock-Eval) Tmax values ranging from 316 and 607°C for shales and mudstones formations and indicating various histories of maturation within the Formation. The level of the maturation is various from immature, late mature to post mature. The production index (PI) values of the studied samples in Belaga Formation ranging from 0.12-0.65 mg HC/g rock.
Marcellus shale characteristics and CO2 adsorption: equilibrium and kinetic modeling study
Authors: Abdulkareem Firas A. , Faugere Gauthier , Radman Amatalrhman , Irfan Sayed Ameenuddin , Sathiavelu Srimanimegala , Padmanabhan Eswaran 
Published: April 2022

Abstract
The CO2 injection in unconventional reservoirs is one of the promising techniques for improved hydrocarbons recovery (IOR) and eliminated greenhouse gas emissions. In this work, the Physico-chemical characteristics of shale rocks, and the influence of those characteristics on CO2 adsorption and desorption are investigated. The mineralogy of four Marcellus shale samples, in addition to the morphology, elemental distribution, functional groups, total organic content, and porosity are indicated and discussed. The adsorption measurements utilizing gravimetric approach show up to 35mg/g and presented obvious correlation of clay minerals existence such as Dolomite, Illite, and Kaolinite at different weight ratios i.e. up to 60wt.% with CO2 adsorption and retention. Open-ended Pore shapes and mesoporous zone are illustrated on the mesoporous shale geometries. The applied numerical equilibrium isotherms modelling, which are Langmuir, Freundlich, Toth, and Tempkin models, are reflected multilayer and heterogeneous gas molecules distribution following the monolayer and homogeneous adsorption. The kinetic measurements showed a rate of adsorption variation, which reflected the total organic content and porosity variations impacts. The temperature program desorption of the pre-adsorbed CO2 gas revealed strong chemisorption on shale matrix, which requested up to 500°C and 2675.538KJ/mol to break down the CO2 bonding from shale geometry. The findings supported the CO2 utilization as water competitor and shale matrix as a storage environment for further utilization or environmental assortments. Keywords: CO2 adsorption/desorption, Marcellus Shales, Kinetics, Hydraulic fracturing, Enhanced Gas Recovery (EGR).
Hydrocarbons and residual oil recovery with ultrasonic-assisted waves and co-solvents
Authors: Abdulkareem Firas A. , Padmanabhan Eswaran 
Published: April 2022

Abstract
In this work, the physicochemical characteristics of the recovered organic fractions and the correlation between organic-makers existence and recovered hydrocarbons are studied on two shale samples from the Kubang Pasu (KP) Formation, Kedah, Malaysia formation. Improving the extractability of organic matter is the key to evaluate the source or reservoir rock petroleum characteristic, this study is an attempt to estimate the optimist extraction technique and conditions for shale rocks. In this work, the physic-chemical characteristics of two moderately organic-rich shale samples from the North-Western Peninsula Malaysia are studied. The recovered organic matter using Soxhlet and ultrasonic extraction processes of the shale samples with toluene is inspected. Samples characteristics in terms of micro-porous surface area and volume analysis, elemental compositions, total organic compounds, surface morphology with elemental mapping, and elemental cations with the active functional groups are analyzed. The solutes of the extraction process are evaluated utilizing gas chromatography and mass spectroscopy (GCMS), and Fourier transforms infrared (FTIR) techniques. The extraction measurements showed a wider range of organic matter recovered from KPK-13 compared to KPK-14 shale. Hence, the total organic content (TOC) of both samples are almost identical (i.e.: ≈ 1.5) which might refer to the higher carbon mineralogy as quantified by EDX mapping, lower surface area according to N2 adsorption analysis, the thermal maturity, or kerogen type of the KPK-14 shale samples. The Soxhlet and ultra-sonication extraction process showed feasible extraction of organic fractions with up to C20. Various configurations of alkanes, alkenes, amines and esters are indicated in the post-sonication solutes with higher weight ratios on the KPK-14 shale sample. The study provides an insightful relation between the organic matter existence and their characteristics, with the possible extractable fractions using the ultrasonic technique as cost and time effective approach.
Pore geometry and connectivity in shaly sand as input data for fracking experiments
Authors: Usman Muhammad , Siddiqui Numair A. , Mathew Manoj J. , Garzanti Eduardo , Shiqi Zhang 
Published: April 2022

Abstract
Exploration for hydrocarbon in shales is an example of unconventional reservoirs for oil and gas resources with huge amount of commercial potential. Porosity and permeability in shale are two important factors that control fluid accumulation and flow. To get the natural shale samples from wells is certainly a hard and crucial job for reservoir fracking studies. To study different factors that influence pore types and geometry in fracking experiments, we carried out X-ray Diffraction (XRD) analysis, surface area analyzer and porosimetry system (SAP), poroperm and tomographic imaging (micro-CT scan) on shale samples from Peninsular Malaysia. The results of synthetic cores through XRD show high amount of clay content (illite/smectite, and kaolinite) and quartz. Other experimental studies reveal that porosity and permeability is heterogeneous and low in the interbedded shale due to very-fine grained matrix. Microscale studies using SEM and CT scan demonstrate different types of pores that are inter/intragranular, intercrystalline, and organic. Our results elucidate that interconnecting pores and their permeability for fluid flow is low due to the obstruction by very-fine grains of clay minerals like illite and kaolinite in shaly sand. The results can be directly applied to labbased fracking experiments that can provide optimal fracking parameters and has great potential in the (oil and gas) O&G industry for understanding hydrocarbon (HC) flow dynamics