bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Methodology for Quantitative Cement Evaluation Using Sonic Logging while Drilling: First Application in Middle East
Authors: Al-Fawwaz Abdullah , Alsenan Duaa 
Published: November 2020

Abstract
Well Integrity is a major concern and a crucial step during the life cycle of the well. That is especially the case after the Macondo incident that changed the perspective of well integrity and proved how misinterpreting the data can lead to severe consequences to the safety of people, financial and environmental impacts. With the new innovations and technologies that we have nowadays, the oil and gas industry has expanded and entered more complex and challenging environments. The technological development of directional drilling allowed better reach and better oil and gas production from the reserves by using multiple angles while drilling. In Saudi Arabia, thousands of wells drilled each year where numerous cement integrity challenges faced especially in high angle wells. Wireline (WL) developed their tools over many years to provide an advanced assessment for cement bond evaluation with a reliable measurement. However, many local cases where observed where cement evaluation through WL was not a possible option due to some challenges such as well control issues and downhole condition. As a result, we needed to implement an alternative solution that can provide a quantitative cement evaluation through different means to address client challenges in cases where the WL service is not a valid option.
Due to the high demand for real-time logging and rig time saving, Logging While Drilling (LWD) expanded its service offerings to address client challenges related to well integrity. In 2004, LWD started to provide top of cement (TOC) service utilizing its sonic tool that indicates qualitatively the presence or absence of cement in the annulus. However recently, LWD developed the first algorithms that delivers a quantitative cement evaluation through an LWD sonic tool utilizing a hybrid methodology. This new approach is a combination of two different types of interpretation which are amplitude-based and attenuation-based methodologies.
This paper will present a successful trial test of the quantitative cement evaluation through LWD that was done in Hout Field in Saudi Arabia and verified with conventional WL cement bond log. The results of this test proved that LWD cement evaluation can be a viable alternative solution to running WL logs. Especially when the conveyance of WL is not feasible or even as a cost-effective solution to save tripping time.
Highly Efficient Modified Activated Carbon as Shale Inhibitor for Water Based Drilling Mud Modification
Authors: Arfaj Mohammed K. , Rana Azeem , Saleh Tawfik A. 
Published: November 2020

Abstract
Maintaining wellbore stability while drilling is critical to mitigate operational problems and reduce well construction costs. This is clearly evident in the case of drilling troublesome intervals such as shale formations. The current study describes the effect of diethylenetriamine modified activated carbon (DETA-AC) on the swelling inhibition of shale samples with high clay content and rheological features of water-based muds (WBM). DETA-AC provides a huge surface area, a prominent number of functional groups, and a relatively non-toxic nature that makes it suitable for environment-friendly additives to drilling fluids. In the current study, the DETA-AC was utilized as an environment-friendly swelling inhibitor. Rheology tests were conducted by hot rolling the WBM at 212°F temperature and 500 Psi pressure for 16 hours. The inhibition features were assessed by dispersion recovery test, shale inhibition stability test, and linear swelling test. The outcomes revealed that DETA-AC modified WBM (DETA-AC-WBM) showed high shale recovery (93.3 %) in dispersion test as related to unmodified WBM (73.6 %), the aqueous solution of KCl (51.5 %), and commercial shale inhibitor mud (74.9%). shale cuttings treated with DETA-AC-WBM displayed stable behavior and resistance against water for up to 2 days. Bentonite in DETA-AC-WBM demonstrated a prominent decrease in linear swelling 58 % as compared to bentonite in water. While the rheological characteristics of DETA-AC-WBM remain almost the same after hot rolling. To confirm the adsorption of DETA-AC on the surface of the clay, its inhibition mechanism was explored by several characterization techniques such as Fourier transforms infrared spectroscopy (FT-IR) analysis, thermogravimetric analysis, scanning electron microscopy, and energy dispersive X-Ray spectroscopy. The proposed inhibition mechanism suggests that DETA-AC carries functional groups that can disturb the hydrogen bonding among H2O and shale material. Subsequently, the clay surface is protected against the adverse effects of clay-water interactions.
Benchmarking of Ultimate Recovery Factor Across Kuwait: Unlocking Additional Potential
Authors: Al-Ghanemi Mohammad , Dhote Prashant , Bora Anup , Al-Bahar Mohammad , Walker Jake , Dharnidharan Bala , Hornbrook John W. 
Published: November 2020

Abstract
A countrywide benchmarking of ultimate recovery factor (URF) for oil reservoirs in Kuwait is presented in this study. The results of this study have been useful to support identification of long-term opportunities and have influenced the creation of conceptual development plans for some of the newly discovered prospects of the company.
The Kuwait Oil Company (KOC) has a diverse inventory of petroleum reservoirs having a wide range of geologic age, depth, reservoir complexity, and development maturity. This study focused on the reservoir complexity index (RCI) method and global analogs to identify development opportunities and improvements to the URF in the brown and green fields of Kuwait.
A customized benchmarking workflow was developed to assess the URF of approximately 100 conventional oil reservoirs. First, a detailed 17-parameter RCI factor and a simplified 7-parameter RCI factor were developed. These two RCI methods were then validated against simulation-estimated URF from waterflood development for the study reservoirs. Next, the two RCI factors were used to benchmark URF for study reservoirs against the company's peers and against global analogs having best practices in operations. Finally, a set of benchmarking dashboards were refined to identify reservoir-complexity concerns, comparisons of company and global peers, and identification of potential upsides or risks in URF.
Comparison of higher performing global analogs to the company's reservoirs with similar RCI resulted in identification of additional development opportunities and upsides in URF.
Assessing Reservoirs' Viability for Long Term CO2 Sequestration Using Cuttings Volatiles
Authors: Smith Michael 
Published: November 2020

Abstract
We present methodology to evaluate long term sequestration viability of CO2 reservoirs using drill cuttings.
Cuttings volatile data was obtained from 2 parallel horizontal wells, drilled along the same vertical trajectories, separated by 400 meters in 2019. One horizontal well drilled within 100 meters of a 1994 vertical oil well. The already produced section shows very low CO2 compared to the rest of this lateral and the entire length of the twin lateral. Oil production from the 1994 vertical well reduced reservoir pressure, caused CO2 loss from formation water, and produced CO2 to the surface, lowering reservoir CO2 contents. This example shows cuttings volatiles analyses can detect past CO2 reservoir loss, and is a valuable tool for evaluating long term storage viability of CO2 reservoirs.
Another horizontal well, different location and formation, produced about one third of the expected oil. Cuttings volatiles indicate that the heel third of the lateral was oil productive, but that oil in the two thirds of the lateral towards the toe had been lost along a major fault. The CO2 contents in the oil pay zone are normal, but in the oil depleted zone CO2 is very low. Loss of oil from the reservoir along the fault reduced reservoir pressure, resulting in dissolved CO2 loss from formation waters, and CO2 loss along the fault.
Cuttings from ten wells from the same limestone formation in a two county area in Oklahoma were analyzed. Nine of the wells show normal CO2 contents. The tenth well drilled across a major fault has 10 to 100 times less CO2 than the other 9 laterals. CO2 in interstitial waters was lost from the reservoir via the fault. Rock Volatiles data indicate the zone drilled by this well is not adequate for long term CO2 sequestration.
A two mile high temperature gas horizontal well was analyzed crosses a major fault near the toe. Very high CO2 contents are observed at the fault. The CO2 is generated in a deeper formation and is migrating out through the penetrated formation. Neither formation is adequate for long term CO2 sequestration.
Cuttings from two CCS wells drilled by the Kansas Geological Survey were analyzed for cuttings volatiles CCS reservoir viability assessment. Both wells show no signs of CO2 depletion, and are considered by us to be low risk for long term CO2 loss.
Rock Volatiles CO2 analyses of cuttings and core is a powerful tool for assessing long term CO2 sequestration viability before new wells are drilled.
A Micro/Nano Scale Fluid Flow Model in Tight Unconventional Reservoirs
Authors: Aldhuhoori Mohammed , Belhaj Hadi , Ghosh Bisweswar , Fernandes Ryan , Alkuwaiti Hamda , Qaddoura Rabab 
Published: November 2020

Abstract
Diffusion forces have been ignored when modeling fluid flow in porous media with a consent belief that viscous transport is the predominant controller. This work introduces a new comprehensive flow model suitable for tight UCRs including viscous, inertia and diffusion forces to account for the transport of fluid in the three scales. A new model addressing multiphase 1-D radial flow in tight UCRs has been mathematically derived and numerically solved, tested and verified against real cases using MATLAB software. A detailed parametric analysis and verification has been carried out and a very clear profiles and flow patterns of the main flow parameters were identified. It has been established that, with lower permeability of the porous medium and lower viscosity of the flowing fluid, the diffusion mechanism becomes more predominant in controlling flow velocity. The results of the newly derived equations that includes the diffusion term have significantly shown the contribution of diffusivity to the flow in the nanoscaled pore spaces as suspected and proven by the numerical models created and the comparison between the suggested equation to other equations and correlations that are used in the field to describe the behavior of the flow in low permeability and low porous medium was established.
Improving Drilling Rate of Penetration Modelling Performance Using Adaptive Neuro-Fuzzy Inference Systems
Authors: Hamdi Zakaria , Haldavnekar Aditya , Momeni Mohammadsadegh , Bataee Mahmood 
Published: November 2020

Abstract
Rate of penetration (ROP) modeling is one of the most important objectives of any drilling program. Penetration model depends on different criteria such as mud weight (MW), weight on bit (WOB), rotary speed (N), and so forth. It is a complex process, because of the high number of variables and uncertainties. Different mathematical models and evaluation methods were developed to solve this problem but they were unable to attain desirable accuracy. Adaptive neuro-fuzzy inference systems (ANFIS) could be used in these cases to predict the rate of penetration. ANFIS is a combination of neural networks and fuzzy logic networks and could be used to create a robust ROP model. The objective of this study is to apply the ANFIS method and compare the modeling results with conventional artificial neural network models. ANFIS trains the model using a set amount of data and then validates it against random data to measure the error. Drill bit record from a certain field has been taken as training data and testing data for the program. The selection process uses the Sugeno model for generating the fuzzy model and the backpropagation and gradient descent method for recognizing the patterns. The data was normalized and sorted out to remove the incomplete values. Tests were done by applying 2 and 3 membership functions to a 4 input interface and a 5 input interface. The accuracy of the results depends on the numbers of inputs and membership functions. Each input was tested with different membership functions to test the data. The output generated from the training process showed that sigmoid function and Gaussian function with grid partitioning and linear output function yielded the best results for 4 and 5 inputs using 2 and 3 membership functions each. The training error recorded was about 3 percent with a checking error of 20 percent for most cases.
A Laboratory Investigation of Factors Affecting Polymer Retention in Carbonate Reservoirs
Authors: Chacko Thomas Nithin , Alfazazi Umar , W. Al-Shalabi Emad , AlAmeri Waleed 
Published: November 2020

AbstractPolymer flooding is one of the widely used chemical enhanced oil recovery techniques. Polymer retention is one of the key factors that affects a successful polymer flooding application at field-scale. This paper evaluates polymer retention of two potential synthetic- and bio-polymers in carbonate reservoirs under harsh conditions. Static retention of the two potential polymers was evaluated through studying different potential parameters that govern polymer adsorption rate, namely soaking time, liquid/solid ratio, rock surface area, polymer concentration, temperature, and sulfate spiking. Pulverized carbonate outcrop samples were used as rock surface medium. The initial and final concentrations of polymer solutions were measured using UV-Spectro Photometer and Total Organic Carbon (TOC) analyzer for the synthetic- and bio-polymers, respectively.Results from the static tests showed that the liquid to solid ratio is the most influential parameter affecting polymer adsorption. Effect of time on biopolymer adsorption is negligible and instantaneous, whereas it took about 6 hours for the synthetic polymer to reach an equilibrium adsorption state with rock powders. Although polymer retention increases with increasing the salinity of the makeup water, acceptable adsorption levels of 250 and 310 µg/g were obtained at a high salinity of 167,000 ppm for synthetic- and bio-polymers, respectively. Polymer concentration is directly affecting the adsorption rate. In addition, the synthetic polymer showed less retention with more promising results as opposed to the biopolymer.The study evaluates several potential parameters affecting static adsorption of potential synthetic- and bio-polymers in carbonate reservoirs under harsh conditions. The paper provides more insight into the effect of sulfate spiking on polymer retention that has not been investigated thoroughly before. The approach used is much simpler than the dynamic retention measurements, but still can be used as an initial screening step before polymer injection tests.
Well Integrity Flow Detection Using Novel Acoustic Pattern Recognition Algorithms
Authors: Noble Lilia , Langnes Tommy , Thiruvenkatanathan Pradyumna , Jones Curt , Fletcher Samantha , Saisbhan Anil , Ali Jinnah-Marie 
Published: November 2020

AbstractThis paper discusses a new technology that helps to identify and differentiate multiple downhole well integrity events - tubing leaks, casing leaks, flow behind casing and overburden integrity, using unique algorithmic pattern recognition capability based on acoustic measurements from Distributed Acoustic Sensing (DAS) data. Here, we demonstrate application of this technology to identify flow behind casing and effectively build remediation strategies for Plug and Abandonment (P&A) of one of the wells in a BP operated field.Applying DAS for tubing leak detection has been discussed in prior publications. The approach has however, relied on simple data processing methods ‘listening’ for zones of increased noise when wells are shut in. In this paper, we discuss results from the application of a novel real time pattern recognition based approach to processing data from DAS that:Denoises data to decouple fluid movement ‘signals’ from background noise Uses signature recognition to constructs fluid ‘flow logs’ across the entire length of the well bore every second; Displays evolution of the fluid noise through depth and timeThe technology has been deployed across several assets for identifying well integrity events through different stages of well life – starting from drilling, production through to abandonment.In this paper, we demonstrate the application of the new capability for identifying flow behind multiple casing strings on one of the BP operated wells. The system was deployed to identify and pattern the evolution of fluid movement noise behind multiple casing strings through time and depth which was then used in conjunction with a tailored operational workflow to inform effective remediation strategies for plug and abandonment of the well. The fluid flow logs generated were used to conclude on the source of flow, flow propagation and pathway and facilitated an informed decision on extending the well’s first lateral barrier into the formation and adjustment of the position of the planned second barrier. The results showed the effectiveness of the capability in the field and demonstrated its unparalleled value for the operator, allowing for well abandonment.The technology offers a new method of acoustic data processing on DAS that extracts valuable and often hidden insights to identify the source of fluid flow and flow pathways, providing an ability of capturing events behind multiple casing strings – all fundamental challenges that the industry has been looking to solve for several decades.
Theoretical Aspects and Practical Implementation of Study of Drilling Fluid Level in the Annulus While Drilling with Total Losses
Authors: Ruzhnikov Alexey 
Published: November 2020

AbstractMany of the matured fields across the Middle East have formations with below-hydrostatic pressure, when drilling is completed without return to a surface. Most of the losses while drilling across vugular, fractured or weak formations happens suddenly, and a fluid level is not visible at the surface. Further the continuous mud cap is applied while drilling to maintain the constant bottom hole pressure. However, the mud cap flow rate and mud weight (MW) most of the time are based on local best practices and not supported by any engineering study, for example using 1.5 ppg at the rate of 1.5 BPM. To have a proper understanding of the fluid level the bottom hole assembly (BHA) is equipped with an equivalent static density (ESD) sensor was used. As continuous mud cap is required while drilling a special procedure was developed to allow tool application.This study was performed initially across the surface section (which together with an intermediate section often has losses in the Middle East), where based on offset well analysis a single lost circulation zone present and the chance of the well control is low. Based on the result of the study the fluid level was clearly identified. Further, to understand the effect of the mud cap flow rate the section was drilled by changing this parameter. The data obtained allowed to understand the effect of a flow rate on the fluid level in the annulus. Having this information the bottom hole pressure can be maintained with lower and constant mud cap flow rate, avoiding risk of wellbore instability or well control, as well as positive financial impact as expensive mud was not used at a high rate to top up the annulus.The obtained information and knowledge explore further the underground behavior of the depleted, fractured and vugular formations across the Middle East. The manuscript can be used by anyone across the world aiming to improve the service quality and reduce the cost related to mud cap as well as have better knowledge to present the well control risk.
Quantification and Correction of Lateral Motion Effects on NMR Logging While Drilling
Authors: Haji Abdullah , Tisdale Colin , Muslem Mohammed , Abouzaid Ahmed 
Published: November 2020

Abstract
Monitoring downhole drilling dynamics is an essential element to quality check the measurements provided in logging while drilling (LWD). LWD nuclear magnetic resonance (NMR) is sensitive to the motion induced from the bottom-hole assembly (BHA) during drilling, therefore, quantifying the motion effects becomes important to understand how to correct the measurements. Quantification and correction of lateral motion effects on NMR LWD are the objectives of this paper.
Data was collected from various BHA combinations with LWD NMR to model the responses, which were compared with actual downhole conditions to assess the need for the lateral motion correction (LMC). Vibrational assessment criteria are utilized to assign a severity level, which dictates the level of the LMC. The LMC applies an algorithm to differentiate true formation signal responses from the vibration signal response. Specifically, the motion effect function was integrated into the forward matrix of the NMR joint inversion, and a nonlinear optimization algorithm was used to determine the four motion parameters, and if present, compensate for lateral motion effects.
In wellbores with severe motion vibration there were large discrepancies between real-time and memory data, which resulted in mismatches with the measured partial porosities. Investigations were conducted on the BHA design, well trajectories, and wellbore environment to quantify the lateral motion effect on the NMR measurement. This information was then compiled to incorporate all aspects of BHA design techniques to mitigate the lateral motion effects on the NMR measurement. The LMC algorithm gives added confidence to ensure all data collected is consistent and reliable even in more challenging wellbore environments, which could be subjected to unanticipated lateral motion.
This paper highlights an approach to integrate BHA simulation principles to anticipate severe motion effects during drilling. This knowledge, coupled with the LMC, creates a platform to enhance NMR data quality.