Petroleum Exploration Activities Research Articles

HEAVY METALS ASSESSMENT AND ASSOCIATED POTENTIAL HEALTH RISK OF BUILDING SEDIMENT DEPOSITION IN OKPARE CREEK, NIGERIA

Heavy metals concentrations in sediments may pose significant threats to human health and well-being of the general ecosystem. Therefore, it's crucial to conduct a thoughtful assessment of sediment characteristics with regards to heavy metal concentration as a raw material for building in the studied area. Twenty sediment samples were collected (five each fromlocalities) and analysed using atomic absorption spectrophotometer (AAS). The highest concentrations of Zn, Cu, Cd, Cr, Pb, V, Fe and Ni were 6.33, 2.65, 0.45, 1,201, 0.38, 0.00, 1026.39 and 0.65 mg/kg respectively in each of the four localities. The results exceeded both recommended limit and other scientist report of similar environment. Also, the health risk impacts computed were all higher than limits. These high values may be attributed tothe nature of the area geological formation, application of fertilizer to the farmlands and petroleum exploration and production activities. Cd stood out as the main culprit for potential ecological risks. The average contamination level, as indicated by I-geo values ranging from 0.28 to 0.79 mg/kg, raisedconcerns, especially at locality 1. Across the board, I-geo values remained generally low (< 2). Cd and Pb, with an I-geo value of about 1, significantly impacted sediment pollution. Average EF values were from 0.02 to 5.76 which revealed that human activities heavily influenced the sediment, marking them as significantly enriched with observed heavy metals. In particular, Cd played a major role in the sediment's enrichment, indicating a high level of environmental impact.

Petroleum Exploration in the Niger Delta Region and Implications for the Environment: A Review

Petroleum exploration and production in the Niger Delta, Nigeria, has been a significant source of revenue and foreign exchange for the country. Nevertheless, this industry has also been blamed for serious environmental pollution in the region. This review aims to shed light on the implications of petroleum exploration in the Niger Delta region and the resultant environmental damage it has caused. One of the most severe consequences of petroleum exploration in the Niger Delta is the frequent occurrence of oil spills. Due to aging infrastructure, poor maintenance, and criminal activities such as oil theft, pipeline spills have become a recurrent problem. Oil spills lead to the destruction of farmland, loss of biodiversity, poisoning of water sources, and widespread contamination of ecosystems. Petroleum exploration and production activities release substantial pollutants into the atmosphere, posing a significant threat to both human health and the environment. The burning of natural gas during oil production, also known as flaring, is particularly prevalent in the Niger Delta. This practice results in the emission of toxic gases such as carbon dioxide, methane, and sulfur dioxide, contributing to climate change, respiratory diseases, and acid rain. Petroleum exploration in the Niger Delta has led to significant damage to forests and mangrove ecosystems. The destruction of these vital habitats has serious implications for species survival. Oil exploration activities often release harmful chemicals and wastes into the region's water bodies. These pollutants infiltrate the groundwater and surface water, leading to contamination that poses severe risks to human health and aquatic life. Contaminated water supplies have been linked to increased instances of skin diseases, as well as liver and kidney problems among the local population. The negative environmental implications of petroleum exploration in the Niger Delta also have severe socioeconomic consequences. Displaced fishermen and farmers face declining livelihoods, while sporadic employment opportunities generated by the oil industry do not compensate for the long-term damage inflicted on the region.

Biogasoline Production from Shallot Skin Waste with KOH-Clay Catalyst to Create Clean Energy

Finding alternative fuels to replace fossil fuels has been made easier by the rise in the consumption of fuels like petrol and the fall in the production of national petroleum exploration activities. This research has been prompted using biomass as an alternative fuel. The primary raw material is shallot skin waste because it has enough lignocellulosic content to be used, one of which is to manufacture biogasoline by using the characteristics of petrol E10. A KOH-Clay catalyst is employed in a thermal and catalytic reaction to influence the reaction's pace. Starting with raw material preparation, conversion procedure, purification, and investigation of the physical properties of biogasoline at specific temperature fluctuations for an hour, the KOH-Clay catalyst is pretreated and characterised. It was discovered through this research that the montmorillonite KOH-Clay content was 5.73, indicating that the catalyst is hygroscopic and absorbs non-polar molecules, making it suitable for use as a catalyst with a pH of 6. As a result, at 60°C temperature circumstances, the best%yield results were attained of 35.025%. While the density value (0.950 gr/cm3) and colour (specific gravity, brownish yellow, and clear/bright) of the experimental results do not meet predetermined standards, they do when viewed from the viewpoint of physical parameters such as specific gravity (0.8358), oAPI biogasoline (37.794), and calorific value (18807.65 Btu/Ib). However, leftover shallot peels generally have the potential to be utilised as clean renewable energy.

2022 Exploration & Appraisal Year in Review

Petroleum exploration activity in Australia decreased in 2022. The total number of exploration wells drilled and expenditure across Federal offshore and state jurisdictions decreased from 2021 levels. The number of exploration permits awarded and acreage made available for exploration was also lower than that of 2021. However, more appraisal wells were drilled in 2022. Onshore exploration expenditure in Australia has exceeded that of the offshore since 2019 and remains the focus of exploration activity. Exploration activity and expenditure has not followed the increase in oil and gas prices of recent years, suggesting external factors are suppressing and impeding exploration activity.

Computational Oil-Slick Hub for Offshore Petroleum Studies

The paper introduces the Oil-Slick Hub (OSH), a computational platform to facilitate the data visualization of a large database of petroleum signatures observed on the surface of the ocean with synthetic aperture radar (SAR) measurements. This Internet platform offers an information search and retrieval system of a database resulting from >20 years of scientific projects that interpreted ~15 thousand offshore mineral oil “slicks”: natural oil “seeps” versus operational oil “spills”. Such a Digital Mega-Collection Database consists of satellite images and oil-slick polygons identified in the Gulf of Mexico (GMex) and the Brazilian Continental Margin (BCM). A series of attributes describing the interpreted slicks are also included, along with technical reports and scientific papers. Two experiments illustrate the use of the OSH to facilitate the selection of data subsets from the mega collection (GMex variables and BCM samples), in which artificial intelligence techniques—machine learning (ML)—classify slicks into seeps or spills. The GMex variable dataset was analyzed with simple linear discriminant analyses (LDAs), and a three-fold accuracy performance pattern was observed: (i) the least accurate subset (~65%) solely used acquisition aspects (e.g., acquisition beam mode, date, and time, satellite name, etc.); (ii) the best results (>90%) were achieved with the inclusion of location attributes (i.e., latitude, longitude, and bathymetry); and (iii) moderate performances (~70%) were reached using only morphological information (e.g., area, perimeter, perimeter to area ratio, etc.). The BCM sample dataset was analyzed with six traditional ML methods, namely naive Bayes (NB), K-nearest neighbors (KNN), decision trees (DT), random forests (RF), support vector machines (SVM), and artificial neural networks (ANN), and the most effective algorithms per sample subsets were: (i) RF (86.8%) for Campos, Santos, and Ceará Basins; (ii) NB (87.2%) for Campos with Santos Basins; (iii) SVM (86.9%) for Campos with Ceará Basins; and (iv) SVM (87.8%) for only Campos Basin. The OSH can assist in different concerns (general public, social, economic, political, ecological, and scientific) related to petroleum exploration and production activities, serving as an important aid in discovering new offshore exploratory frontiers, avoiding legal penalties on oil-seep events, supporting oceanic monitoring systems, and providing valuable information to environmental studies.

Physicochemical, Biochemical and Genotoxic Profile of Subchronic Exposure of Wister Rats to Treated Crude Oil Exploration Water

Background: Crude oil exploration water is the major waste product generated from petroleum exploration and production activities and is known to be a complex composition of numerous hazardous chemicals, including large quantities of heavy metals, inorganic, and organic substances and naturally occurring radioactive materials (NORMs).
 Objectives: This study was designed to investigate the physicochemical, biochemical and genotoxic profile of subchronic exposure of Wister rats to treated crude oil exploration water (TCOEW).
 Materials and Methods: Fifty rats were randomly assigned to five treatment groups, with ten rats per group, and treated with five concentrations (1%, 5%, 10% and 20%) of TCOEW. Each TCOEW concentration was administered for 90 days ad-libitum as normal drinking water to each group, while the control group was given tap water. Blood, liver, kidney, thymus, spleen and femoral bone of the animals were collected at the end of exposure for biochemical and histological assessments. The pH, conductivity, and turbidity were carried out on-site, while other physicochemical parameters were determined using standard laboratory methods. Data were analysed using descriptive statistics and ANOVA at α 0.05.
 Results: Treated crude oil exploration water caused a significant (p < 0.05) increase in RBC, PCV and Hb while other hematological and biochemical parameters showed no difference. Also, TCOEW cause a significant increase in polychromatic erythrocytes (PCEs) in genotoxicity test and no major lesion were seen in the histopathology studies. Treated Crude Oil Exploration Water does not comply with FEPA standards of produced water due to high conductivity, salinity and total dissolved solid of the sample. The marked increase in micronuclei polychromatic erythrocyte formation (MNPCE) showed that TCOEW might be genotoxic and this could be responsible for the significant increase RBC, parked cell volume (PCV) and hemoglobin (Hb) observed.
 Conclusion: Although TCOEW does not totally meet FEPA standard for effluent discharge, it has mild genotoxic effect.

Exploration and appraisal year in review 2022

Petroleum exploration activity in Australia decreased in 2022. The total number of exploration wells drilled and expenditure across Federal offshore and state jurisdictions decreased from 2021 levels. The number of exploration permits awarded and acreage made available for exploration was also lower than that of 2021. However, more appraisal wells were drilled in 2022. Onshore exploration expenditure in Australia has exceeded that of the offshore since 2019 and remains the focus of exploration activity. Exploration activity and expenditure has not followed the increase in oil and gas prices of recent years, suggesting external factors are suppressing and impeding exploration activity. Twenty-six exploration wells were drilled in the year compared to 29 in the previous year, resulting in one offshore and eight onshore petroleum discoveries. The Pavo oil discovery in the Bedout Sub-basin and in the same exploration play as the Dorado oil discovery of 2018, was the only offshore discovery in 2022. Onshore exploration ‘hot-spots’ include the Northern Perth Basin and the Cooper–Eromanga Basin. The Permian Kingia Sandstone play of the Northern Perth Basin yielded the South Erregulla and Gynatrix gas discoveries, and the Jurassic Namur Sandstone play of the Cooper – Eromanga ‘Western Flank’ was extended yielding the Bangalee-1, Coorong-1, Magic Beach-1 and Rocky-1 oil discoveries.

High-quality source rocks in an underexplored basin: The upper Carboniferous–Permian succession in the Zaysan Basin (Kazakhstan)

The Zaysan Basin is a petroliferous basin in eastern Kazakhstan. Its upper Carboniferous–Permian sedimentary succession outcrops in the Kenderlyk Trough and includes, from base to top, the Kenderlyk, Karaungur, Tarancha, and Maychat formations, which contain 5 to 65 m-thick oil shale deposits—the principal subject of this study. Results from 49 outcrop samples show high total organic carbon (TOC) contents (1.2–21%, mean 7.8%), extract yields (1.2–15 mg HC/g rock, mean 6.8 mg HC/g rock), and ultimate expulsion potential (UEP; up to 23 mmboe/km2), making these oil shale deposits among the best source rocks in the world. Sedimentological, organic geochemical and organic petrographic analyses suggest an overall evolution of the basin from a deep/semi-deep lake during deposition of the Kenderlyk, Karaungur, and Tarancha formations to a deltaic setting during deposition of the Maychat Formation. The organic material in the Kenderlyk, Karaungur, and Tarancha formations is predominately composed of Type I and mixed I/III kerogens with high hydrocarbon generation potential (S1 + S2; up to 172.8 mg HC/g rock), high hydrogen index (HI; up to 838 mg HC/g TOC), and low oxygen index (OI; < 60 mg CO2/g TOC). The sporadic influx of terrigenous organic matter resulted in layers with lower HI and higher OI index, and increased inertinite and vitrinite contents. The Maychat Formation includes hydrogen-poor Type III kerogen with low HI (< 200 mg HC/g TOC) and high OI index (> 60 mg CO2/g TOC) in the Kenderlyk Trough. While a highly oxidizing environment during deposition of the Maychat Formation is postulated for the Kenderlyk Trough, it is likely that oxygen-depleted conditions in the depocenter of the Zaysan Basin favored accumulation of Type I kerogen. The oil-source correlation shows that the produced oils are chemically distinct from the source rock extracts of the Kenderlyk, Karaungur, and Tarancha formations. We propose that these source rocks are “massive”, where the retention of generated oil is too high, causing the hydrocarbons to “bleed” from the source rock's edge only. The expelled oil has probably charged the lower Permian deposits, which have not yet been explored. Regional geological cross-sections and seismic lines allow for selecting sweet spots, characterized by high TOC, yields, and temperatures needed for oil generation and unconventional hydrocarbon resource development.This study provides the play concept and a risk assessment analogue for tectonically and magmatically dynamic settings and basins with multiple organic rich strata. Furthermore, the results and proposed concepts may play a significant role in future petroleum exploration and development activities in the Zaysan Basin. In addition, this highly multidisciplinary study emphasizes the significance of integrating several data sources and weighing contradictory information to get the most reasonable conclusion.

Investigation of the behavioral and neurotoxic effects of sub-chronic exposure of Wistar rats to treated crude oil exploration water (produced water)

Treated crude oil exploration water (TCOEW) is a significant byproduct created from petroleum exploration activities and is known to be a complicated synthesis of numerous dangerous chemical materials. This study is designed to evaluate the behavioral and neurotoxic effects of sub-chronic exposure of Wistar rats to treated crude oil exploration water (produced water). Fifty rats were randomly assigned to five treatment groups, with ten rats per group, and treated with five concentrations (1%, 5%, 10% and 20%) of TCOEW. Each TCOEW concentration was administered for 90 days ad-libitum as normal drinking water to each group, while the control group was given tap water. After sub-chronic exposure of 90 days, the behavioral effect of TCOEW was investigated using open field test (novelty-induced behavior), elevated plus maze (anxiety), novelty object recognition test (short-term memory) Morris water maze (spatial memory), and the neurotoxic effects by biochemical and histological assessment of the brain. Data were analysed using descriptive statistics and ANOVA at α 0.05. TCOEW produced a significant (p &lt; 0.05) reduction in novelty-induced rearing, grooming, and locomotion. Also, TCOEW reduced the index of open arm entry IOAA in EPM, and time spent exploring the novel object in NORT. TCOEW-exposed groups had significantly higher annulus time and higher annulus crossing in Morri’s water maze. This study provides evidence that the treated crude oil exploration water might contain chemicals, which on chronic exposure, have effect on behavior, learning and memory and anxiety.

CAGE13-5 Cruise Report: Investigation of glacial geomorphology in the Storfjordrenna.

The course GEO‐8144/3144 Marine geology and geophysics cruise, taught at the University of Tromsø, is part of the obligatory courses to be completed by PhD students affiliated with the AMGG research school and yields 5 credits (ECTS). Participants include scientific staff and students.&#x0D; This cruise was conducted within the framework of&#x0D; &#x0D; the Norwegian Science Council (NFR) project Glaciations in the Barents Sea area (GlaciBar) and&#x0D; the trainee school in Arctic Marine Geology and Geophysics (AMGG) financed by the University of Tromsø. The cruise was funded by AMGG.&#x0D; &#x0D; The main target areas are the Storfjordbanken and Storfjordrenna south of Svalbard. The cruise addressed marine glacigenic processes of the areas, with a focus on the last glacial-interglacial cycle in order to reconstruct in a more detail way the retreat of the Barents Sea–Svalbard Ice Sheet.&#x0D; To collect data have been used different methods and instruments, which will be described in a more detailed way in chapter 3. Below here there is only an overview:&#x0D; &#x0D; Multibeam echo sounder: Sound-wave beams are transmitted in a fan perpendicular to the ship track from a hull-mounted echo sounder. Produces high-resolution seafloor bathymetry.&#x0D; Chirp: High-resolution acoustic profiling.&#x0D; CTD (Conductivity, Temperature, Depth): Sensors installed in a frame measure CTD properties of the water column. Generally used for oceanographic studies, but here mainly to calibrate the multibeam data from calculated velocities.&#x0D; 2D seismic: GI airguns and hydrophone cable (streamer).&#x0D; Sediment coring: Gravity coring.&#x0D; Gas sample collection.&#x0D; &#x0D; The targeted study area is under-explored compared to similar areas (Bjørnøyrenna) in the SW Barents Sea. The study areas in the Storfjordrenna and Stordfjorbanken are shown. Several different features have been identified on the seafloor, like MSGLs, grounding zone wedges, flares, pockmarks and ploughmarks. All these features will be described in detail in chapter 4.&#x0D; In addition, 9 gravity cores were acquired in areas likely to provide information on the timing of the formation of the sediment accumulation. The specific core locations were chosen based on information from multibeam swath bathymetry and chirp data. Furthermore, gas samples were collected from the cores from pockmarks and will be analyzed later.&#x0D; The new results add new detailed data regarding the deglaciation of the Storfjorden trough. Glacial geomorphologic features similar to the ones in Bjørnøyrenna were discovered. The observation of gas flares were the first such discovery in the northern Barents Sea. The discovery of flares and pockmarks might have a big impact on future petroleum exploration activities in the region.&#x0D; The cruise may be known as: HH_2013_GEO_8144_3144

Using legacy core material to assess subsurface carbon storage reservoir potentiality

Abstract The growing importance of subsurface carbon storage for tackling carbon emissions requires an accurate characterization of potential reservoirs to understand their capabilities. In this context, the use of legacy data originally acquired in the last fifty years for scientific projects and petroleum exploration and production activities would represent a suitable cost-effective solution and help to maximize the value of this extended national asset. Core material represents the only direct observation of subsurface deposits and must be preserved from the current disposal process related to the decommissioning of hydrocarbon fields. In this contribution, a suite of samples from core material stored at national (i.e. British Geological Survey) and local (i.e. Department of Earth Sciences, Royal Holloway, University of London) core repositories, previously characterized at the micro scale using X-ray micro-computed tomographic (μCT) imaging are discussed. Using this technique, it has been possible to investigate how pore and grain geometries control crucial features of a suitable reservoir such as porosity and permeability. The aim of this contribution is to describe the methodology behind digital image analysis (DIA) following μCT imaging applied to core material. We show how DIA can be used to provide significant measures of reservoir suitability when making initial assessments of storage reservoirs, without the need for expensive and time-consuming analyses.

Exploration &amp; Appraisal Year in Review 2021

Petroleum exploration and appraisal activity increased in 2021. Exploration spend increased for the year, continuing a positive trend. Onshore exploration and appraisal activity continues to dominate the petroleum exploration scene in Australia.

Concurrent 13. Presentation for: Exploration and appraisal year in review 2021

Presented on Wednesday 18 May: Session 13 Petroleum exploration and appraisal activity increased in 2021. Exploration spend increased for the year, continuing a positive trend. Onshore exploration and appraisal activity continues to dominate the petroleum exploration scene in Australia. Positive indications of increased work program bids (wells, seismic and spend) are, however, tempered by the downward trend of total exploration acreage (by area) and new acreage awards. In addition to petroleum exploration acreage, greenhouse gas sequestration acreage was released across Australia in 2021. Twenty-nine exploration wells were drilled in the year compared to twenty-five in the previous year. Eight conventional petroleum discoveries were reported, with the Artisan-1 discovery in the Otway Basin being the only offshore discovery. The Lockyer Deep-1 gas discovery in the Northern Perth Basin continues the exploration success of the Permian Kingia and High Cliff Sandstone play. The Cooper–Eromanga Basin continues to yield discoveries with the Odin-1, Rosebay-1, Lowry South, Liger-1 and Chimera-1 discoveries reported for the year. Thirty-one appraisal wells were drilled for the year with significant activity in the Northern Perth Basin, Cooper-Eromanga Basin and Bowen-Surat Basins. Exploration and appraisal drilling also continued in the Beetaloo Sub-basin with the drilling of the Tanumbirini-2H, Tanumbirini-3H and Carpentaria-2/2H wells during the year. To access the presentation click the link on the right. To read the full paper click here

Exploration and appraisal year in review 2021

Petroleum exploration and appraisal activity increased in 2021. Exploration spend increased for the year, continuing a positive trend. Onshore exploration and appraisal activity continues to dominate the petroleum exploration scene in Australia. Positive indications of increased work program bids (wells, seismic and spend) are, however, tempered by the downward trend of total exploration acreage (by area) and new acreage awards. In addition to petroleum exploration acreage, greenhouse gas sequestration acreage was released across Australia in 2021. Twenty-nine exploration wells were drilled in the year compared to twenty-five in the previous year. Eight conventional petroleum discoveries were reported, with the Artisan-1 discovery in the Otway Basin being the only offshore discovery. The Lockyer Deep-1 gas discovery in the Northern Perth Basin continues the exploration success of the Permian Kingia and High Cliff Sandstone play. The Cooper–Eromanga Basin continues to yield discoveries with the Odin-1, Rosebay-1, Lowry South, Liger-1 and Chimera-1 discoveries reported for the year. Thirty-one appraisal wells were drilled for the year with significant activity in the Northern Perth Basin, Cooper-Eromanga Basin and Bowen-Surat Basins. Exploration and appraisal drilling also continued in the Beetaloo Sub-basin with the drilling of the Tanumbirini-2H, Tanumbirini-3H and Carpentaria-2/2H wells during the year.

Radiological Impacts of Petroleum Exploration Activities in Ras Qattara Area, North Western Desert, Egypt.

Radiological Impacts of Petroleum Exploration Activities in Ras Qattara Area, North Western Desert, Egypt.

The Geochemical Study of Oil-Oil and Oil-Source Rock Correlations in the Wushi Sag of the Beibu Gulf Basin, South China Sea

Chemometrics has been widely used to cope with the problems of oil-oil and oil-source correlations because of its unique advantages in the comprehensive consideration of multiple parameters and the classification of samples or variables. In this paper, three chemometric methods, especially multidimensional scaling, were used to revisit the genetic oil family and the relationship between the crude oil and the source rock, because the oil source in the Wushi Sag, a significant petroliferous sag in the Beibu Gulf Basin of South China Sea, is still controversial. Two genetic families of crude oils, namely group A and group B, have been identified based on chemometric results. Group A oils are characterized by relatively higher Pr/Ph ratios and a high abundance of C27 ααα 20R steranes and C30-methylsteranes than those of group B oils, suggesting that this group of oils was deposited under a more oxic condition with more contribution of algae organic matter. Group A oils have been interpreted to be a mixture derived from the member 2 and member 3 of the Liushagang Formation (LS-2 and LS-3), whereas group B oils can be ascribed to the LS-2 member. The contribution of LS-3 mudstone member to the Wushi oils in previous studies may have been underestimated to some extent, which was inferred from the chemometric oil-source correlation results. The results of oil-source rock correlation may be used to guide future petroleum exploration activities with the incorporation of geological evidence. The spatial distribution of oil and gas reservoirs varies with burial depth. Taking into consideration other geological evidence, we may infer that the reservoir in eastern Wushi Sag was mainly distributed in the deep of Liushagang Formation, whereas the reservoir in southeast Wushi Sag was likely located in the shallow Liushagang Formation.

Evaluation of Geophysical and Geochemical Characteristics of Soil and Groundwater Resources in Yenagoa Environs, Niger Delta, Nigeria

The problem of potable water has increased in recent time due to increase in population density, petroleum exploration activities and spillages along the creeks. Thus, three (3) Vertical Electrical Soundings (VES) were made using Schlumberger array in the study location to obtain geophysical data, using the ABEM SAS 1000 terrameter, in order to investigate the occurrence of groundwater in relation to the depth and thickness of viable aquifer. Six (6) surface water samples and six (6) subsoil samples were obtained from the study area. Both subsoil and surface water samples were analyzed to determine the concentration of contaminant. Analysis was performed using the Atomic Absorption Spectroscope (AAS) method which was compared with the World Health Organization Standard. Result and interpretation of analyses revealed high contaminant contents of lead (Pb) with values of subsoil samples at S2 (18 mg/l) and S6 (8.1302 mg/l), while Mn show very high concentration of contaminant values for all subsoil samples which exceeded the WHO permissible standard which indicates that aquifer may likely be polluted by intrusion. Cr for subsoil samples and Mn of surface water samples are likely within or slightly higher concentration value when compared with WHO limit. It is advisable to carry out proper water treatment from source and soil degradation, for potable drinking water and cultivation of agricultural product respectively.

Environmental Impacts And Social Concerns - A Case Study Associated With Petroleum Exploration Activities From Onshore Baram Delta, NW Sarawak

The onshore Baram Delta, located in NW Sarawak is the birthplace of petroleum production in Malaysia. The Miri oilfield was first discovered in 1910 and subsequently abandoned in 1972 with intermittent exploration activities in the late 1980’s to early 1990’s. To rejuvenate exploration interest and to identify remaining hydrocarbon potential of the study area, in 2009-2010 JX Nippon acquired gravity, then regional 2D seismic data, followed-by exploration well drilling from 2011-2014. This paper discusses the social-environmental impacts and concerns associated with these petroleum exploration activities, from acquisition of seismic where explosives and vibroseis were used as a source of propagating signals, to exploration drilling with petroleum chemicals such as water-based muds used to facilitate the drilling operations. Overall, the inquiry addresses operational challenges, security of explosive storage and concern for handling explosives in the field, the social-environmental impacts of seismic acquisition operations, as well as removal of drilling fluid chemicals and disposal of contaminated cuttings. Containment procedures and mitigation measures undertaken to alleviate these social-environmental impacts are discussed according to the guidelines and regulatory requirements provided by the Environmental Impact Assessment (EIA), in conjunction with PETRONAS Procedures and Guidelines for Upstream Activities (PPGUA) and the company’s Health, Safety and Environment (HSE) Management System. In the final analysis, significant environmental and social challenges were certainly encountered while planning and conducting petroleum exploration activities in the study area. These challenges include problems related to topographic variabilities, permitting issues, compensations for affected lands and cash crops; layout constraints, drilling operations, well control measures for blowout prevention, traffic controls, potential damage to infra-structures, explosive and equipment transportation. However, with proper planning, effective communication with the local authorities, and awareness sessions conducted for the affected parties and stakeholders; together with the support of the local communities the operations have not only managed to mitigate these social and environmental concerns, the exploration activities also provided economic benefits such as hotel accommodation, logistics and transportation demands for local businesses, and short-term employment opportunities for the local people. Ultimately, the operations successfully acquired nearly 900-line km of seismic across many villages, longhouses, and in the city areas, with four exploration wells were drilled in the exploration block. We are glad to report that both seismic and drilling operations were conducted successfully and safely with minimal interruptions to people and environment, without untoward incidents or spills. With the mitigation measures in place, there were no damages other than land access, which were remediated, where incurred.

The Application of Parametric and Nonparametric Regression to Predict The Missing Well Log Data

DOI:10.17014/ijog.8.3.385-399Incomplete well log data are very commonly encountered problems in petroleum exploration activity. The development of artificial intelligence technology offers a new possible way to predict the required logs using limited information available. Optimizing conventional statistical theory, machine learning is proven to be a reliable tool for any prediction task in many fields of study. Regression is one of the basic methods that has rapid development and evolved many techniques with different approaches and purposes. In this study, parametric and nonparametric regressions {linear regression, Support Vector Machine (SVM), and Gaussian Process Regression (GPR)} are compared to predict the missing log using the available nearby data. Feature selection was done by performing Principal Component Analysis (PCA) on predictor variables. Different profile of PCA is observed between Cibulakan and Parigi Formations, which is the basis of conducting separate models based on the formation. Among all the selected methods, GPR is consistently making slightly better results. The correlation between the predicted and actual porosity of GPR is observed to be up to 0.19 higher compared to the other methods. Similar observation is also found on the Root Mean Squared Error (RMSE) value comparison. In practice, the GPR method has an inherent advantage compared to other methods, as it provides uncertainty to the prediction based on the standard deviation of each estimation result. The standard deviation of the GPR prediction ranges from 0.006 in high confidence cases and up to 0.077 where uncertainty is high. The models are considered robust and stable according to the RMSE evaluation from cross validation which is consistently giving the value below 0.04. In conclusion, the reliability of regression techniques for predicting the missing well log is exposed in this study, which results demonstrate steady and good accuracy in every formation which are tested on any well logs.

Canalization induced topographic, hydrologic, and land use changes in Olero Creek, Benin River owing to petroleum exploration activities.

Canalization carried out during petroleum exploration is contributing to environmental changes in the Niger Delta. We carried out a study on five decades of canalization in Olero Creek, Benin River, from 1980 to 2020. The study site covered an area of 36.40 km2. Satellite imageries of five epochs (1980, 1990, 2000, 2010, and 2020) and Shuttle Radar Topographic Mission (SRTM) of 2000, which provided digital elevation models (DEMs) of the study area were collected and analyzed using ERDAS IMAGINE 9.2 and ArcGIS 10.6 software. We found that the total length of dredged canal increased from 14.14km in 1980 to 61.07km in 2020, spoil banks doubled from 2.05 km2 in 1980 to 4.13 km2 in 2020, and direct wetland loss doubled from 3.76 km2 in 1980 to 7.57 km2 in 2020, with the largest increase occurring between 1990 and 2000. The land use/land cover, topography, and hydrology of the area also changed. Water bodies that originally accounted for 1.17% of the study area in 1980, increased to 22% in 2020, Rhizophora racemosa fringing the waterbodies increased from 11% in 1980 to 47% in 2020, and Rhizophora mangle decreased from over 55% in 1980 to about 23% in 2020. The results of digital elevation model show that the surface area is undulating with the relative topography of the study site ranging from - 5 to 40m. We conclude that canalization during petroleum exploration was contributing to land use, topographic, and hydrologic changes in the study area.