bluuebunny/crossref_metadata_2025 huggingface dataset:
Multicultural Counseling in Islamic Perspective
Authors: Basit Abdul
Published: August 2020

In this globalization and information era, the role of multicultural counseling is very urgent for the community. Given the cultural exchange between one country and another country is so massive. If a counselor only focuses on the client's person without regard to the cultural factors influence it, then the process of implementing counseling can cause bias and ineffective. In its historical development, the theory and practice of multicultural counseling is still dominated by multicultural counseling originating from the West. Meanwhile, Indonesia is a country where the majority of the population is Muslim and in terms of culture differs from rational, individualist, and materialist of Western cultures. Therefore, this paper describes multicultural counseling in an Islamic perspective as an alternative to the development of multicultural counseling in Indonesia. The different human concepts, cultures, and values developed by Islam form the basic foundation in the multicultural counseling process. From this basic difference, the author further explains the competence and practice of multicultural counseling in Islam, especially in Indonesia. In obtaining the comprehensive data, the authors conducted a qualitative study by taking data sources derived from the al-Qur'an, al-Hadith, and the results of the thinking of Muslim scientists related to multicultural counseling.
Determinants of Under-Five Mortality in Ghana: Evidence from the Ghana Demographic and Health Survey
Authors: Nyaaba Albert Apotele , Tanle Augustine , Dadzie Louis Kobina , Ayamga Matthew
Published: August 2020

Background and Objectives:

This study aims to investigate the strength of the association between socioeconomic, maternal and environmental determinants and under-five mortality in Ghana.

Methods:

We utilized data from the 2014 Ghana Demographic and Health Survey, a population-based cross-sectional study, which included 4151 children born alive to women aged 15-49 years. The primary outcome variable was under-five mortality. Descriptive statistics and multivariate logistic regression were applied to assess the relationship and relative association of the independent variables with the outcome variable.

Results:

Children of women with secondary education and above and women within the middle wealth status were 0.593 and 0.886 less likely to experience under five deaths compared to women with no education and women of low wealth status (OR=0.593; 95% CI 1.690 to 2.063; p< 0.01) (OR =0.886; 95% CI 1.48 to 1.63; p<0.01). Women who had their first child between the ages of 20-29 were 0.764 less likely to have children die before age 5 compared to those women who had their first child between the ages of 15-19. (OR= 0.764; 95% CI 0.994 to 1.191; p<0.0l). Children born in households with pit toilets were more likely (OR= 1.51; 95% CI 1.20 to 2.30; p<0.01) to die before age five compared to children born in households with flushed toilet. Women who used borehole/well-water were more likely (OR= 1.686; 95% CI 2.94 to 3.01; p< 0.05) to experience under-five deaths compared to women who used piped water.

Conclusion and Implications for Translation:

This study identified the determinants that significantly predicted under-five deaths and the magnitude of the influence on under-five deaths in Ghana. It accentuates the need for increased maternal education, delayed childbearing age, provision of improved drinking water and toilet facilities to reduce under-five deaths in Ghana.
The Lake Wright Patman Cache
Authors: Brooks Robert
Published: August 2020

Thirty-nine bifaces found in the collections of the Museum of the Red River were recently analyzed. Mr. Donald Stewart recovered these bifaces from the vicinity of Lake Wright Patman during lake construction. Analysis of the biface cache was undertaken to gain some understanding of these specimens, despite the absence of provenience information and other details pertaining to their collection. Basic metric data and non-metric observations were taken. I also detail the collection of the biface cache, the history and archaeological background of Lake Wright Patman, results of the analysis, and some thoughts on the function of the bifaces.
The Decorated Ceramic Sherds, Plain Rim Sherds, and Clay Pipe Sherds from the Stallings Ranch Site (41LR297), Lamar County, Texas
Authors: Perttula Timothy
Published: August 2020

Excavations at the Gene and Ruth Ann Stallings Ranch site (41LR297) during the 2005 and 2006 Texas Archeological Society Field Schools, as well as 2004 excavations by the Valley of the Caddo Archeological Society, recovered an interesting assemblage of prehistoric ceramics. In this article, I analyze the 88 decorated sherds, the 99 plain rims, and the 67 clay pipe sherds found during that work. In addition to characterizing the assemblage of vessel sherds and pipes in terms of decorative style and various technological attributes (i.e., temper and paste, firing conditions, surface treatment, etc.), I am also concerned with establishing the temporal and cultural affiliation of the recovered ceramics, particularly with respect to determining whether the ceramics found at the Stallings site are primarily from a Fourche Maline Woodland period occupation or a later, post-A.D. 800 Caddo ancestral occupation.
An Engraved Bulbous-Necked Caddo Bottle from 41OR33 at the mouth of the Sabine River, Orange County, Texas
Authors: Perttula Timothy
Published: August 2020

41OR33 is a large prehistoric shell midden deposit in Orange County, Texas, about 8.5 miles southwest of the city of Orange, at the mouth of the Sabine River and just north of Sabine Lake in Southeast Texas. Before the site was destroyed for road fill in October 1956, limited archaeological investigations had been done there by avocational archaeologists and then by E. Mott Davis of The University of Texas at Austin. During that work, a number of Native American burials were exposed and excavated, including one burial with an engraved bulbous-necked ancestral Caddo ceramic bottle. The bottle was donated by Edgar W. Brown, Jr. to UT in October 1956. I recently documented this vessel, which is a far-flung companion to bulbous-necked and spool-necked Caddo bottles from post-A.D. 1600 sites in the Red River and Ouachita River basins in East Texas and Southwest Arkansas as well as several post-A.D. 1600 sites in East Texas such as the Taylor site (41HS3) in the Big Cypress Creek basin.
Asociación de multirresistencia bacteriana y mortalidad en recién nacidos de muy bajo peso al nacimiento
Authors: Lona-Reyes Juan Carlos , Cordero-Zamora Araceli , Pérez-Ramírez René Oswaldo , Arambul-Carrillo Cuauhtli Emmanuel , Gómez-Ruiz Larissa María , Jiménez-Hernández Denisse Sinaí
Published: August 2020

No disponible
Technology Focus: Simulation (July 2020)
Authors: Burgoyne Mark
Published: August 2020

As the world struggles through the COVID-19 crisis and our industry suffers from linked oversupply and demand reduction, we are all forced to refocus on what makes a difference to the bottom line.In the numerical reservoir simulation space, that is generally, "How do we answer a decision-related question in the least amount of time with an acceptable degree of confidence?" Simulation has always been a double-edged sword - a method that, when well-used in fit-for-purpose ways to answer specific questions, can deliver real value. Conversely, when it is used as a substitute for understanding, perhaps to justify a development decision or simply to convince ourselves that we understand a system far better than we really do, many staff years of effort can be quickly lost while not delivering very much. Fit-for-purpose approaches likely will be of ever-increasing focus going forward. If it is not adding value, it should not be done. But "fit for purpose" encompasses a wide range of possibilities - leveraging new approaches as well as learning from old approaches and improving current approaches. It is these three prongs that have guided my paper selections for this edition. While the rapid rise to prominence of methods that eschew conventional numerical modeling approaches in favor of data-driven proxy approaches provides us with some new tools to answer these questions, these tools are unlikely to be reliably predictive unless they incorporate governing physics. It is for this reason that one of the following papers spells out just such a solution, marrying fundamental material-balance governing equations with analytics-driven clustering techniques to deliver what appears to be a fit-for-purpose approach to a complex problem. Keeping in mind the quote attributed to George Santayana - "Those who cannot learn from history are doomed to repeat it" - the second paper is an interesting look back at different attempts to simulated unconventional plays, while the third paper is an interesting extension of a current approach to well deconvolution. I hope you enjoy reading this selection of papers and look forward to what the future may hold in the numerical simulation space.
Canadian Oil Sands Output Cut 1 Million B/D What Could Go Wrong?
Authors: Rassenfoss Stephen
Published: August 2020

When Matt Fox, chief operating officer for ConocoPhillips, was asked about how the company is managing its 100,000 B/D reduction at its Surmont project, the response was reassuring.

“We’re not doing anything that’s going to take any risk either from a reservoir or wells or facilities perspective. That’s why … in Surmont, we’re going down to a minimum rate, so that we can still provide enough heat and temperature to the steam chambers to keep them intact,” Fox said during a recent call with stock analysts.

To be clear, he is not saying there is no risk. ConocoPhillips and others are using various methods to turn down production that maintain the heat and pressure they spent years creating in reservoirs where pairs of wells are used to inject steam to heat bitumen. Gravity then drains the melted bitumen down to the production well in a process known as steam-assisted gravity drainage (SAGD).

While what they and other companies in the oil sands are doing is commonly described as shutting in wells, they are actually slowing the production from those wells. Some use reduced steam injections in a well pair, alternate cyclic injection among wells, or injections of gas to maintain the pressure.

“It is a good test case,” said Scott Norlin, a research associate at Wood Mackenzie. The geologist who used to work in the oil sands said shutting in wells is not a good description of how they are cutting production.

“It is almost like cooking a turkey for Thanksgiving,” and dinner is delayed, so “you turn the temperature down. You’re not throwing it back in the freezer,” he said.

Future productivity in wells that have been turned down requires maintaining the temperature and pressure at levels high enough to preserve the steam chamber - the area above the injection where the water vapor thins peanut-butter-thick bitumen so it can flow.

Keeping it hot enough to maintain the steam is critical because if it is allowed to condense into liquid form, it will cause a pressure drop which can open the door for serious trouble.

The minimum safe injection level will vary based on factors ranging from a water layer next to the steam chamber to the age of the well.

Years of steam injections warm the rock around the productive zone, slowing cooling if the injections are stopped or reduced. If there is a water zone in contact with the production zone, too little steam may allow an influx of water, which would quench the steam chamber.

“If we cut the steam rate, but keep it high enough to supply the heat loss, and thus maintain the steam temperature (which means pressure), the production rate will go down, but the steam chamber will continue to exist without resaturation,” said S.M. Farouq Ali, a distinguished professor at the University of Houston Cullen College of Engineering.
Technology Focus: Health, Safety, and Environment (August 2020)
Authors: Knode Tom
Published: August 2020

One year ago, this editorial communicated the exciting progress within the SPE health, safety, and environment (HSE) discipline and shared a preview of the 2020 SPE International Conference on HSE and Sustainability, which was to be held in Bogota, Colombia, in March.

The high-level focus of our discipline’s flagship biennial event is “Generating Pride and Enabling Engagement,” and the 100-person-strong program committee spent months building an excellent balance of papers and speakers. What we did not know at the time was that, shortly before our conference was to start, our industry would find itself coping with a historic drop in oil prices and society would be fighting a global pandemic.

SPE responded by postponing this and other conferences to protect the health and safety of our members. The good news is that the 2020 HSE and Sustainability conference will go ahead at the end of July 2020 as one of the first fully virtual conferences and exhibits offered by the SPE. As you read this edition, its participants will be wrapping up what will undoubtedly have been another successful knowledge-sharing event.

Our industry has had a swift response to the pandemic by deploying mitigation processes several weeks before the World Health Organization even declared it a pandemic. A study from the University of Houston entitled “The Energy Workforce and COVID-19: Data-Driven Policy Recommendations” indicates that the industry has taken appropriate actions. Planning is a key element to managing any emergency, and there will be many lessons learned to share as we recover from this threat. One paper included in this section covers the response to infectious diseases in offshore operations.

A new Safety Leadership Academy, webinars, and other training courses, as well as conferences and regional and local events, can and will serve as the means for development in HSE. In this low-oil-price era, with pressure to reduce costs, it is of the utmost importance that we have engaged and well-informed HSE leaders across the industry.

2019 also saw the arrival of a new strategic initiative - the Gaia Program. It is a nonhierarchical multistakeholder community enabled by SPE and other professional associations with the basic premise of helping ensure oil and gas comes out on the right side of history - valued for its contributions, yet agile and imaginative enough to evolve with changing expectations of its role in society. SPE Live, which can be found on SPE’s LinkedIn page, regularly features Gaia Talks, if you’d like to join and learn more.

This selection of technical papers focuses on all aspects of HSE and sustainability. A library of technical papers can also be found in OnePetro and on the HSENow online publication.
Machine-Learning-Assisted Closed-Loop Reservoir Management Using Echo State Network for Mature Fields under Waterflood
Authors: Deng Lichi , Pan Yuewei
Published: August 2020

Closed-loop reservoir management (CLRM) consists of continuous application of history matching and optimization of model-predictive control to maximize production or reservoir net present value (NPV) in any given period. Traditional field-scale implementation of CLRM by using a large number of reservoir models, in particular when uncertainty is accounted for, is computationally impractical. This presented machine-learning-assisted workflow uses the echo state network (ESN) coupled with an empirical water fractional flow relationship as a proxy to replace time-consuming simulations and improve the computational efficiency of the CLRM. The ESN, under the paradigm of reservoir computing, provides a specific architecture and supervised learning principle for recurrent neural networks (RNNs). ESNs, with randomly generated and invariant input weights and recurrent weights, greatly minimize the computational load and solve potential problems during typical backpropagation through time in traditional RNNs while it still obtains the benefits of RNNs to memorize temporal dependencies. Also, the linear readout layer makes the training much faster using analytical ridge regression. Field-level well control and production-response data are fed into the workflow to obtain a trained ESN and fitted fractional-flow relationship, which will represent/reproduce the dynamics of the reservoir under various well-control scenarios. Further production optimization is directly applied to the matched models to maximize reservoir NPV. The optimized well-control scenario is applied, and further observation is obtained to update the models. History matching and production optimization are performed again in a closed-loop fashion. The previously mentioned advantages make ESN a very powerful tool for CLRM, with both history matching and production optimization quickly accomplished, and make near-real-time CLRM possible. In this paper, two case studies will be presented to prove the effectiveness of the proposed workflow.
A Semiempirical Model for Rate of Penetration with Application to an Offshore Gas Field
Authors: Etesami Danial , G. Shirangi Mehrdad , Zhang W. J.
Published: August 2020

In this paper, we present an accurate semiempirical rate of penetration (ROP) predictive model for polycrystalline diamond compact (PDC) bits. Our model is inspired by the model of Bourgoyne and Young (B&Y) and follows an exponential form with 10 different drilling functions to account for various factors affecting ROP in drilling operations. We extend the B&Y model to the PDC bits and discuss that a different predictive model should be obtained for each formation. On top of the factors included in the original B&Y model, our model accounts for parameters such as downhole motor, equivalent circulating density, mechanical weight on bit (WOB), and wellbore inclination. In particular, we incorporate the effect of equilibrium cuttings bed thickness and downhole cuttings concentration in the ROP model. The parameters of the model are obtained using multiple regression analysis with the field data. The importance of obtaining a formation-based ROP model is tested and verified with field data, and an algorithm to determine the parameters for new data is provided. The model can be incorporated in a framework to obtain an optimal well plan for a new well or for prescribing optimal operational parameters for well planning and real-time drilling operations. The prediction performance of the proposed model is also evaluated in various formations for several test wells across an offshore gas field. Our results indicate that the proposed model is able to predict the drilling ROP with an accuracy of more than 90%.
Experimental Determination of Protein Enzyme Bio-Surfactant Properties for Enhanced Oil Recovery
Authors: Morgan Anthony , Akanji Lateef , Udoh Tinuola , Mohammed Shaibu , Aggrey Nkrumah Wilberforce , Sarkodie-Kyeremeh Justice
Published: August 2020

The properties of Protein enzyme biosurfactant, a green-enzyme, water-based inert-enzyme generated from the DNA of microbes that eat oil was studied to ascertain its applicability in EOR processes. A light crude oil of 0.908 g/cc at 22°C density and 53.87 cp viscosity was used in this study with a kinematic viscosity which was variable between 90.654 mm2/s to 13.7544 mm2/s between temperatures of 22.5 °C to 70 °C with a measured surface tension of about 35 mN/m. The bio-surfactant yielded a CMC value of 0.02 wt.% which is comparable to reported CMC values of other surfactants. The least IFT value measured was 4.0 mN/m, which is very high for a very efficient and effective residual oil recovery (an ultralow IFT of about 0.01mN/m is required of which was achievable by Rhamnolipid a bio-surfactant studied alongside Protein Enzyme in this work). Ionic (0.083M to 3.0M) and temperature (23 to 70 °C) effects did not have much influence on the activities of bio-surfactant, thus quite stable within such conditions. The protein-enzyme has the ability to form a Winsor type III emulsion and stable over the period of time studied. Adsorption was noticed especially with higher bio-surfactant concentrations but tends to be stable over time.
The Benefits of the Installation of Live Gas-Lift Valves During the Initial Well Completion Phase of a Well, Addax Petroleum Development Company as a Case Study
Authors: Ifediora Emmanuel Eberechukwu
Published: August 2020

The installation of dummy valves with the initial well completion for gas lifting wells has been a popular practise in the industry. These dummy valves provide a barrier between the annulus and the tubing during the well completion phase to the test the tubing and annulus independently after the well is flanged up. These dummy valves are later changed out for live valves in preparation for lift gas injection when the reservoir energy becomes too low for the wells to flow or when the desired production rate is greater than the reservoir energy can deliver due to water production. Whereas this completion method has endured, it has escalated the clean-up cost, and maintenance cost of these wells because the intervention operations for gas lift changeout are often time consuming and costly.

To minimise the above costs due to the installation of these dummy valves during the initial completion phase, Addax Petroleum Development Company adopted the use of live valves during the initial completion. After completing the well with brine, it requires to be underbalanced to unload the brine and clean out before producing to the sales line. For under saturated reservoirs and depleted reservoirs, coil tubing with Nitrogen injection had been used to initiate the underbalance for the well clean up because of its low density and high-pressure characteristics. Today to further reduce the well clean-up cost, Addax Petroleum Development Company now pumps Nitrogen or lift gas through the casing-tubing annulus and the live gas lift valves to under balance and off load the well.

Also, with the introduction of live gas lift valve installation, the cost of the dummy valve changeout, with consequent production deferment during the intervention process has been eliminated.

This paper highlights the benefits Addax Petroleum Development Company has derived from the installation of live gas lift valves with the initial completion by reducing the completion and clean-up cost in each well completed, and the consequent elimination of well intervention cost for a gas lift changeout.
Investigating the Nexus Between Nigerian Rig Rates and Crude Oil Prices
Authors: Ojukwu Kelechi Isaac , Ajienka Joseph , Dosunmu Adewale , Iledare Omowumi , Ibe Chidi
Published: August 2020

This study set out to investigate how Nigerian oil rig rates respond to oil price fluctuations, and the lag between them aimed at developing models for forecasting land, swamp and offshore rigs rates in Nigeria.

The research methodology involves application of Ordinary Least Squares regression to develop models that can predict land, swamp and offshore rig rates, which can be used in the Nigerian market. Firstly, Brent crude oil prices are exogenous to Nigeria, whilst land, swamp or offshore rig rates are endogenous. Furthermore, these exogenous variables are regressed with and without lag to test the response time between the cause and its effect.

A striking relationship is observed between these independent variables similar to global trends. Like other countries, the Nigeria oilrigs count trends along with Brent crude oil price. However, a 3-4 months lag exists between Nigerian rig rates and oil prices. Furthermore, the model estimation using one-year lag seems to show more accuracy in matching the historical rig rates and the more expensive the rig, the wider the margin caused by oil price changes. This confirms the possibility to predict Nigeria rig rates and perhaps, well costs from oil price forecast.
Using Limited and Cheap PVT Data to Reduce GOC Uncertainties in Reservoirs with Unknown GOC
Authors: Okoh Oluchukwu M. , Lawal Kazeem A. , Yadua Asekhame U. , Odude Adebayo , Anyanwu Obinna T. , Ovuru Mathilda I. , Eyitayo Stella I. , Pelemo Bosun , Akewusola Taye , Matemilola Saka , Ramaswamy Sunil , Nwaeri Edwin
Published: August 2020

There are direct and indirect methods to define a gas-oil contact (GOC) in a petroleum reservoir. The direct method requires drilling a well to penetrate prospective fluid contacts. The indirect methods, which include, compositional grading simulation (CGS), do not require evaluating prospective GOC with a dedicated well. However, the CGS technique is currently deemed not applicable in cases of limited pressure-volume-temperature (PVT) dataset.

By exploiting a new framework developed by Okoh et al. (2020), this paper demonstrates the applicability of CGS to petroleum reservoirs characterized by limited PVT dataset. This method entails estimating the degree of under-saturation of a given fluid sample at a known sample depth. Using known fluid gradient and estimated saturation pressure gradient of the fluid sample, this degree of under-saturation is converted to its equivalent depth to estimate a potential GOC within a connected reservoir. Empirical models for estimating saturation pressure gradient and bubble-point pressure of an oil sample at in-situ conditions are presented. Considering the need for a reliable estimate of the in-situ bubble-point pressure, different bubble-point empirical models are examined for their suitability and accuracy.

Several examples of saturated and undersaturated reservoirs from the Niger Delta are used for validation tests. Overall, the bubble-point correlation by Ikiensikimama and Ogboja (2009) was found to be the most appropriate for the intended application. Additionally, the validation tests confirmed the robustness of the proposed method for predicting potential GOC in petroleum reservoirs that have limited PVT dataset. While the scope of validation of this paper has been limited to the Niger Delta, we expect the proposed method to perform satisfactorily in the treatment of similar problems in other basins.
Creating a Digital Twin of Part of the Earth Subsurface through Reservoir Navigation Service
Authors: Imomoh Victor Bello , Toyobo Oluwaseun , Okafor Rosemary
Published: August 2020

A digital twin can be said to be a virtual model of a physical body, living or non-living. By bridging the physical and the virtual model, data is transferred seamlessly allowing the virtual model to exist simultaneously with the physical body. It is, therefore, a digital replica of a possible and actual physical assets, systems, places, persons or devices.

The success of any reservoir navigation service involves team effort from many disciplines that include engineering, well planning and design, geological study and a host of other fields. This usually results in lots of digital data from planning to execution, as well as a post-project stage where best practices are adopted for the next project.

This paper will focus on showing how the reservoir navigation service earth model can be seen as a digital twin of a section of the earth and how advances have already been made in this light to aid in creating a perfect digital twin of the earth for geosteering purposes.
Production Enhancement Using Micro-Emulsion Technology in Ogini and Isoko Fields
Authors: Ajao Wale , Onwuchekwa Chukwuma , Isiba Ezinwanneakolam , Oke Oluwatobi , Ideh Matthew , Agbaroji Victor , Okon Willie , Ageh Ebenezer
Published: August 2020

Near wellbore impairment result from various factors such as mud invasion, filter cake deposition, and fines migration in producing fields. Micro Emulsion Chemistry, other than the traditional acid stimulation presents a new and novel remedial treatment for near wellbore impairment. A microemulsion is a typical Newtonian fluid system distinguished from emulsions owing to its being stable thermodynamically and self-organizing.

This technical paper explains the process of candidate selection, data gathering, job execution, and resultant crude oil gain from deploying micro-emulsion technology (MET) on some strings in the Ogini and Isoko fields. The fields have different and unique challenges. While the Ogini field has characteristic heavy oil and viscous crude, the Isoko field has wax deposition challenges. Deploying MET treatment in both fields yielded record-breaking results and productivity (PI) improvements in multiple folds. A total of 3,500 bopd (incremental oil) was achieved from treatment on four strings in both fields.
Allocation of Processed Natural Gas Streams Under a Gas Tolling Arrangement
Authors: Kanshio Sunday , Tahir Salahuddeen M.
Published: August 2020

Gas tolling is a business model where the owner of the tolling plant (a gas processing plant) receives raw gas from multiple suppliers, processes the gas and returns the products to the suppliers of the raw gas for a fee. This study investigates the effect of hydrocarbon commingling on the output products quantities of a conceptual gas tolling plant. The study also compared three allocation methods, namely, proportional, shrinkage factor and composition-based allocation method. In a situation where there are multiple suppliers, the raw gas composition and flowing conditions would vary considerably. In the processing plant, the gas undergoes phase change due to varying physical properties and plant operating conditions. The proportional and shrinkage factor method requires fewer measurement data but do not obey the principle of equitability in the allocation of the products streams. The composition-based allocation, which was carried out using the UniSim Design Production Allocation Utility, allocates the products streams equitably by tracking the phase changes in response to any changes in flowing conditions of the contributing sources.
Probability Approach to Casing Design Using Monte Carlo Simulation
Authors: Muoghalu Amalachukwu , Ansa John , Dosunmu Adewale
Published: August 2020

Casing design plays an important role in the successful drilling of a well and accounts for a substantial percentage of well costs. The goal of casing design is to get an optimal design that will withstand stress and other factors that affect casing throughout the lifetime of the well. The conventional approach to casing design uses a deterministic working stress design (WSD), where minimum strength requirements of the casing are determined by comparing casing strength to the magnitude of severe accidental loads that may occur during the lifetime of the well. Uncertainties in the load and strength of the casing are accounted for by multipliers called safety factors (SFs) that are mostly based on experience and do not reflect the probability or consequence of the different casing failure modes. This approach may result in overly conservative casing designs, or design requirements for severe conditions that are expensive, leading to higher well costs.

In this paper, the Monte Carlo Simulation (MCS) method is applied to casing design, where uncertainties in casing loads are considered explicitly by assigning probability distributions to safety factors that affect design loads. As the MCS method predicts the casing safety factor probability, it gives a better view of the real uncertainties involved in the design. Acceptable probabilities of casing design load can be selected based on the cost and operating conditions the casing will undergo; thus, a probability approach to casing design is more flexible as it allows an explicit uncertainty-consistent designs compared to traditional working stress designs.
Improved Correlations and Predictive Models for Nigerian Crude Oil Pvt Properties Using Advanced Regression and Intelligent Techniques
Authors: Uzogor Kingsley , Akinsete Oluwatoyin
Published: August 2020

Calculating reserves in an oil reservoir and also the determination of its performance and economics needs a sound knowledge of the fluids’ physical properties. Bubblepoint pressure, Oil FVF at bubblepoint, solution GOR and compressibility are of primary importance in material balance calculation. Ideally, the laboratory measurements of PVT properties are the primary sources of PVT data gotten from laboratory studies of the samples collected from the wellbore or from the surface. However, such experimental data are not always available mainly due to unreliability of the data from samples or that samples have not been taken as a result of cost saving as the operation can be quite expensive. It therefore became pertinent to be able to predict these properties in the absence of the experimental data. Several correlations have been developed to enhance this prediction but, unfortunately, these correlations are highly region dependent and rarely works well in different regions since they were developed with data from particular regions.

The objective of this study is to develop better performance correlations and predictive models for the Nigerian crude oil PVT properties using linear and non-linear multivariate regression techniques and supervised machine learning techniques. This study focuses on predicting bubblepoint pressure, Pb, oil formation volume factor at bubblepoint, Bob, and solution gas-oil ratio, Rs, as functions of the reservoir temperature and the oil and gas gravities.

In this study, evaluation and tuning/recalculation of coefficients (using linear and non-linear regression analysis) of some of the best PVT correlations to estimate the desired PVT parameters and employing the KNN and the Random Forest algorithms to develop better PVT models for the Niger Delta region, were performed. After adequate pre-processing, the gathered dataset was divided into training and test datasets by random sampling. Average absolute Relative Error, Root Mean Square Error and the Correlation coefficient, R are the main loss functions employed to evaluate and compare the developed models with the conventional correlations.

The new models showed much better performance as regards the Niger Delta crude PVT properties. With respect to the best performing conventional correlations for the Nigerian crude, the new models decreased the RMSEs by 72%, 61.1% and 83% and increased the correlation coefficients by 35%, 7.2% and 26.9% for the bubblepoint, oil formation volume factor and solution gas-oil ratio respectively.
Information Management: Key Strategic Tools to Unlock the Barriers to Marginal Oil Field Development in Niger Delta
Authors: Oruwari Humphrey Otombosoba
Published: August 2020

The aim of the study was to evaluate information management as key strategic tools to enhance marginal field operations in Niger Delta. Using literature review and case study of marginal fields operating in the region. The significant values of information are examined, against the background of barriers to marginal oil field development. Specifically the inability to develop some of the fields is traced to information asymmetry in oil and gas operations and the inability of the system to manage and use existing information. Understanding the strategic roles of information will assist stakeholders in establishing its usefulness as a tool for leveraging on competitive advantages in order to improve the bottom line. Some recommendations are made as what should have been done to improve marginal field operations among which are: Educate communities about oil companies’ obligations and the Department of Petroleum Resources (DPR) should develop and launch a web based portal that advertises available geo-data on a block by block basis.
Implementation of a Well Integrity Management System in the Nigeria Agip Oil Company Joint Venture NAOC JV Using Peloton WellView Software
Authors: Adebajo Adeyemi , Emuchay Daniel , Adeyinka Olubunmi , Oseni Damilola , Onasanya Babafemi , Wopara Promise , Onyekwere Victor , MacDonald Chris
Published: August 2020

The NAOC JV, comprising 20% NAOC, 20% Oando Oil Ltd, and 60% NPDC working interests, owns over 400 wells in OML 60 - 63 within the Niger Delta region of Nigeria. To ensure well integrity and protect property, lives and the environment throughout the well life cycle, first and second line wellhead maintenance activities involving greasing, leak testing, function testing, repair and replacement of tree valves and down-hole safety valves (DHSV) are carried out based on approved well integrity programs.

The Well Integrity Management System (WIMS) provides guidelines for first line wellhead maintenance activities frequency in line with API recommendations; second line wellhead maintenance is carried out on an as needed basis to ensure the integrity of all wells throughout their lifecycles.

WIMS implementation using WellView is a smart well integrity surveillance system that generates and sends auto emails to selected users on well integrity issues based on preset criteria for leak rates and casing pressure limits. This has been effective in timely identification of issues before they become major problems. It also triggers proactive actions on critical wellhead system components that are nearing failure based on results of analyses.

This paper describes the workflow, strategy adopted by our IT team, coding developed by Peloton WellView consultants and issues encountered in achieving this feat; current issues and proposed solutions are also discussed.
Uptime Improvement for Selected Intermittent Oil Producers
Authors: Nnanna Erasmus , Ezekwugo Joseph
Published: August 2020

Production wells normally experience different phases of life, starting with the initial ramp-up phase after drilling and completion, through the plateau period and finally to the decline phase. The tail-end of the decline phase often present with intermittent production behaviors requiring ‘tender-loving care’ to maximize production performance. Wells normally quit in this phase of production and may require a period of pressure build-up before being re-opened to production. Primary reason for this behavior is increase in watercut or decrease in reservoir pressure or a combination of both. Typically, intervention actions on intermittent wells are based on initiation of artificial lift, water shut-off or production in a cyclic manner if there is no scope for these. The typical production cycle of a cyclic well goes from normal production through unstable production (fluctuating wellhead pressures) to eventually quitting. Whereas every naturally producing well eventually quits, paying close attention to operating conditions of cyclic wells can enhance their availability and unlock significant production volumes for the asset.

SPDC, a Joint Venture Organization in Nigeria with oil and gas wells spread across the Niger Delta, has about 64 intermittent producers; 54 oil wells and 10 gas wells. These producers are approaching the tail-end of their lives and therefore produce in a cyclic manner-with uptime and downtime cycles. Driven by the desire to improve integrated production system capacity (IPSC), there has been a renewed focus on this category of wells towards improving their uptimes. An approach deployed to improve the uptime (availability) of these wells involved the optimization of well operating envelopes. This implied moving the operating points of the wells to the stable region of inflow/outflow performance curves after challenging the basis for the current operating envelopes. This led to the adjustment of choke sizes, increase/decrease of gaslift injection rates and relocation of chokes from wellhead to the manifold.

Five pilot wells were selected for this project with operating envelope reviews carried out and adjusted based on detailed well performance analysis. The result is cumulative average uptime of 256 days versus historical cumulative average of 91 days (more than 100% improvement in uptime) for the 5 wells. The production gains achieved within a period of 3 months was over 50,000 bbls at no extra operating cost and no additional technical risk.
Evaluating the Effects of Petrophysical Properties on Oil Initially in Place
Authors: Essien Alicia , Akpabio Julius
Published: August 2020

In oil and gas exploration and production, it is essential to have a reliable estimation of Oil initially in Place (OIIP). Reliable reserve estimation depends on the petro physical data used in the volumetric method of estimating OIIP. This estimation is done at the primary phase of exploration where production data are not yet available. The effects of petrophysical data and their sensitivity on OIIP were determined. Average petrophysical data were obtained from reservoir X, Y and Z within the Niger delta and analyzed by running a Monte Carlo simulation using computer-based application such as MS Excel and MS Minitab (Design of Experiments (DOE). 10,000 random data sets were generated for each petrophysical property from the average field data obtained from Reservoirs X, Y and Z in the Niger Delta region. The simulation results were further analyzed using sensitivity indices and Tornado plots. For reservoir X, the percentage effect of porosity, oil saturation, pay thickness, drainage area, oil formation volume factor (oil FVF) on OIIP were 97, 95, 90, 70, and 5 respectively. For Reservoir Y, the percentage effect of porosity, oil saturation, pay thickness, drainage area, and oil FVF on OIIP were 95, 89, 83, 58, and 4 respectively. For Reservoir Z, the percentage effect of porosity, oil saturation, pay thickness, drainage area, and oil FVF on OIIP were 95, 89, 80, 75, and 4 respectively. Results from the various analysis carried out proved that porosity had the highest and positive effect on OIIP, followed by oil saturation and pay thickness, oil formation factor has the least significant effect and in some cases negative effect on estimated OIIP. In the long run, these understanding will help the reservoir engineer identify the sensitivity of each parameter when carrying out volumetric estimation of OIIP and also the need for sourcing quality reservoir and petrophysical data using different available cost-effective and efficient methods.
22yrs After Longford Gas Plant Explosion, are We Threading the Same Path?
Authors: Shittu Ganiyu Adio
Published: August 2020

On Friday, 25 September 1998, the Esso Australia's gas plant at Longford in Victoria suffered a major fire. Two men were killed, eight injured and the state's gas supply was severed for two weeks, causing chaos in Victorian industry and considerable hardship in homes, which were dependent on gas.

The main cause of the fatal accident was attributed to a re-organization of the site personnel that led to drastic reduction of personnel available on site.

Hence, several experience personnel were moved to the office to provide support to field locations and the situation which led to the fatal incident was not managed properly because of lack of knowledge of the team on site.

Oil and Gas companies are back to restructuring and reorganization to manage the difficult economic terrain and competition to drop the cost/barrel, are companies taken note of the lessons from Longford or are they just focusing on the team structure without proper risk assessment for safe change management. Companies have introduced lean projects or restructuring to manage the number of personnel onboard producing fields to the barest minimum with intention to reduce the number of personnel exposed in case of emergency, manage the cost/barrel and also make experienced personnel available at a center designated either as SMART Room or Support center to provide services to all field locations instead of these personnel staying on different sites which will require more personnel.

Personnel involved in this program were engaged and their experiences taken on board to provide a preliminary information on these new concepts for management to focus on the blind spots.

Therefore, Lost Time Injuries (LTI) data are largely a measure of the number of routine industrial injuries, however explosions and major fires are rare, do not contribute to the LTI figures in the normal course of events. LTI data are thus a measure of how well a company is managing the minor hazards, which result in routine injuries, but they tell us nothing about how well major hazards are managed. Hence, the great performance being recorded with the migration to new structures should not make us lose the fact of the potential dangers if the rapid changes are not managed with painstaking change management to ensure all sections are adequately risk assessed and compensated for realistically.
Robust Diagnostics Optimize Decisions on Innovative Deepwater Gravel-Pack Interventions for Water Conformance
Authors: Khong Chee Kin , Sookram Neil , Mukerji Parijat , Cruz Mauro , Martins Fernando , Zett Adrian
Published: August 2020

Surveillance in deep water wells is cost prohibitive. There is a need for significant hydrocarbon production or water shutoff incentive to justify the intervention in such wells. The wells straddle multiple stacks of soft sediment reservoirs, being completed with open hole gravel pack. While laterally extensive barriers between various sands units might help the water shutoff / containment, the gravel pack annulus still provides a conduit for water to move upwards and jeopardize the shutoff success. In this campaign a meltable alloy was deployed to plug the flow in both annulus and screens.

In deep water subsea wells, water conformance control is often attempted blindly without flow diagnostic surveillance or production logs as a minimum. This can impact the production due to plugging substantial hydrocarbon production or inadequate flow from the remaining zones. Candidate wells or techniques for shut-off require robust diagnostics to improve the success rate and limit loss of oil or gas production.

In a recent well work campaign production logs were acquired to optimize the water shut-off. Well access is challenged by limited rigup height (short lubricator) and well deviation. The well trajectory impacts the phase presence, mixing and recirculation. It requires a short array of sensors conveyed on tractor. Logging while tractoring capabilities in surface readout mode is required to minimize the rig time, improve depth control and perform real time data quality assurance.

The multiple mini-spinners, electrical and optical probes are all positioned to the well's vertical axis to capture all local changes in the flow regimes. Sensor arrangement is sufficiently compact in this tool to minimize flow disturbance by tool occupancy and movement along the well. Real-time profiling of the complex flow regimes during the acquisition provided better log control and understanding of the downhole phase dynamics.

Changing the mindset about subsea deep-water reservoir surveillance paid dividends in water shutoff operations, both for immediate decision make and for longer term well and reservoir performance management. There was a net benefit by deploying a compact axial array production logging string that allowed accurate rate and phase allocation and further identification of zones to be isolated using an innovative plug-back method that significantly reduced the water production.