bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pilot Gas Injection Design in Two Middle East Carbonate Reservoirs
Authors: Dabbouk C. , Namba T. , A-Alim Mohammed S. 
Published: December 2007

Abstract
This paper presents a pilot gas injection design in two massive carbonate reservoirs in one of the middle east fields. The eastern part of the field, where both reservoirs depict good reservoir characteristics, has been developed by the application of five-spot water injection patterns. However, in the western part of the field which is under primary development, a sharp decline in reservoir characteristics isnoted. Anunexpected water breakthrough occurred in the eastern part while production from the western part is declining due to lack of pressure support. Under these situations, a decision was taken to assess the effectiveness of gas injection in enhancing the oil recovery and providing pressure support. This paper is focused on the pre-pilot investigation, selection of pilot areas, laboratory experiments (solubility and swelling tests, slimtube and coreflood experiments), development of Equation of State (EOS), compositional sector model studies and the monitoring programme.
Horizontal Drilling Performance Analysis
Authors: Al Attas M.O. 
Published: December 2007

Horizontal Drilling Performance Analysis.

Abstract
Abu Dhabi Marine Operating Company (ADMA-OPCO) drilled its first horizontal well in 1989 in Abu Dhabi offshore area in the Arabian Gulf. Since then ADMA-OPCO has gone along way. By 1995 over 100 horizontal wells have been drilled using different techniques.

Introduction
As time passes and more experience was gained, the more drilling performance had improved. This is clearly indicated by the drilling rate of penetration (ROP) which will be highlighted in this paper. ROP is one of the main tool used to measure performance but it is not the only factor. Others such optimization of bottom hole assembly (BHA), mud and milling fluid stimulant acid and introducing new equipment are used as measuring tools for the performance. The content of this paper is based on a number of studies conducted by ADMA-OPCO for the last seven years. It aims to highlight the major factors affecting th performance means of measurement.

WELL TYPES
There are two types of horizontal wells that are necessary for the development of offshore area oil fields namely:Producing wellsInjecting wells
Data for both types have been used to support the results high lighted by this paper.
There are various techniques used in drilling horizontal wells. The scope of this paper is to cover the main techniques used by ADMA-OPCO and in particularly those which have an impact on drilling performance. The various techniques covered here in, are as follows:Medium radius curvature.Short radius curvature.Open a window in 9 5/8" casing (re-entry wells).Milling 7" liner (re-entry wells).Drilling single, dual and multi lateral drains.
The following are the subject means for measuring drilling performance:

1. ROP
The good ROP was achieved by combination of optimizing of drilling equipment parameters, drilling fluid and introducing new drilling equipment.

2. DRILLING COST
This was achieved by either having good drilling ROP or reducing the well's expenditure by eliminating some used equipment.
P. 838
Multi-Lateral Horizontal Drilling Problems & Solutions Experienced Offshore Abu Dhabi
Authors: Ismail Gamal , El-Khatib H. 
Published: December 2007

Abstract
ZADCO's Offshore oil field which is a stacked reservoir system was considered as one of the optimum candidates for horizontal drilling applications. The flourishing of horizontal drilling technology has completely changed the development strategy criteria of the reservoirs.
In early 1989, horizontal drilling was experimented in ZADCO's Offshore field, which became an essential part of the new reservoir development program. Eighty five horizontal wells were successfully drilled and completed.
A rapid development in horizontal profile was achieved in ZADCO's Offshore field using the latest horizontal drilling technology to drill complex Multilateral horizontal wells: Multilateral in different directions from parent well bore, Multilateral with two branches in one thin reservoir, Multilateral with Stair-step/traverse trajectories to minimize drilling through tight barriers and to delay water breakthrough.
Several problems were encountered while planning, drilling, completing & stimulating the complex multilateral horizontal wells such as:
Maintaining zonal isolation among the various reservoirs.
Minimizing the drilled footage through tight barriers/poor facies, to control sweep efficiency and to delay water breakthrough by drilling stair step or traverse hole trajectory
Anchor-stock utilization.
Drilling multilateral horizontal wells with low departure target.
The development of thin & tight oil reservoir
Minimizing casing cement bond failure by drilling multilateral holes from one window.
Target centralization within multilateral sections in different directions
Stimulation of multilateral barefoot completion.
The paper will focus on the solutions of above problems experienced in the multilateral horizontal wells implemented in the field offshore Abu-Dhabi.

Introduction
This field, which is one of the largest oil producing fields in the Middle East, is situated in offshore Arabian Gulf about 80 km North West of Abu Dhabi Emirate island.
The field was discovered in 1963, development started in 1977 by utilizing conventional drilling methods. Horizontal drilling was introduced in 1989 and an extensive multilateral drilling was implemented in the last two years.
The concept of using horizontal wells to improve recovery and controlling sweep efficiency was introduced in the oil industry since 1920s. In recent years thousands of horizontal wells have been drilled world-wide to achieve this concept at a lower monetary investment.
The extensive experience of steerable drilling system and remarkable improvement in horizontal drilling technology, encouraged ZADCO to drill complex multilateral horizontal wells.
Ensuring Materials Procurement Quality through Third Party Inspection and Materials Certification – The ADCO way
Authors: Dhamija Lalit K. 
Published: December 2007

ABSTRACT
Operating companies buy materials worth million of dollars every month. There are numerous cases where materials received are not as per the requirements and this results in significant losses in terms of down time and costs of corrective actions required to procure the desired materials.
In the oil and gas industry many operating companies have reported that the lack of "fitness for purpose" due to non-conformances costs more than 10% of equipment costs. Users, engineers, purchasers & inspectors of materials need to give the proper attention which material procurement deserves. Necessary care is required in preparing buying description/ selecting specifications of the materials and on improving methods of procurement, inspection, traceability, certification and re-certification. Third Party Inspection (TPI) is a powerful tool to ensure quality of purchases made by a company. TPI, if properly applied, prevents cost and time over-runs. For TPI to be effective, a proper methodology has to be followed at various procurement stages.
This paper describes the ADCO'S activities in ensuring that procurement quality is achieved in a cost and time effective manner. The use of materials certification is also explained. There is a discussion on what to look for in a material certificate and why material certificates are rejected.
The paper also describes issues relating to management of TPI activities and various ADCO initiatives to improve procurement quality.
An Estimate of the Uncertainty of Residual Oil Saturation Derived from Log-Inject-Log Measurements from a Middle East Carbonate Reservoir
Authors: Wiltgen Nick , Al-Merikhi Sultan , Al-Othman Ibrahim 
Published: December 2007

abstract
As production declines in a reservoir, management is confronted with the question: Do we have sufficient hydrocarbons remaining for an improved recovery project to be economically viable? The answer requires a knowledge of the remaining recoverable reserves which are determined from the residual oil saturation (Sor). Hence Sor is essential to calculate the reserves that can be produced by the proposed project. The additional income can then be compared with the required expenditures necessary for its implementation to enable establishing whether the project meets the required profitability criteria.
I lowever, a project must not be judged on profitability alone. Its riskiness must also be taken into account. If we have two projects with the same profitability, the one that is less risky is obviously preferred. Riskiness can be defined as a measure of the uncertainty of achieving expected results. Riskiness depends on many factors but one of the most crucial will be the uncertainty in the recoverable reserves which is directly dependent on the uncertainty in the measured Sor. Clearly an assessment of the uncertainty in Sor is very important.
Applications of Coiled Tubing in Zadco Wells
Authors: Hassan M. M. , Abu Sharkh A. F. 
Published: December 2007

ABSTRACT
Recent improvements in coiled tubing technology and reliability have resulted in an impressive participation of coiled tubing units in drilling / completion operations and well services such as stimulation, liquid nitrogen lifting, testing, logging etc. for oil and gas wells.
This paper presents an operational overview of ZADCO experience in applications of coiled tubing (C/T) as follows: a) velocity strings in wedk flow well, b) pack off strings for corroded production tubings c) acid conveyer for stimulating deviated and horizontal wells.
The case history of running C/T as a velocity string in two ZADCO wells has resulted in a continuous flowing wells and a marginal improvement in the wells' productivity.
The program for utilizing C/T as pack off string in ZADCO wells was not implemented yet due to logistics problems and changes in the workover program. However, a brief theoretical plan / running procedure is highlighted.
Also, this paper presents the benefits of using C/T for placing acid across low permeable subreservoirs which results in maximizing the well's oil production.
Predicting the Initial Reserve and the Performance of High Pressure Gas Reservoirs
Authors: Elsharkawy Adel M. 
Published: December 2007

ABSTRACT
A challenging problem confronting reservoir engineers these days is the estimation of the initial gas in-place and prediction of the performance of high pressure gas reservoirs because of the effect of formation compressibility and possible water influx from small associated aquifer or embedded shales. Several material balance models have been proposed to estimate the initial gas in-place and predict the prevailing production mechanisms for such reservoirs. However, most of these models have prier assumption about either the formation compressibility or the aquifer size.
This paper presents a material balance solution plot. The solution includes gas expansion, reservoir condensate expansion, rock expansion, formation water expansion, water influx from associated aquifer, water influx from embedded shales, and gas evolved from formation water.
Application of the material balance solution plot described in this paper shows that this solution plot successfully estimate the initial gas in-place and predict the prevailing reservoir production mechanism. Comparison of the new solution explained in this paper with the others shows that the new solution is more simple and accurate than the others.
Development of ADCO's Environmental Management System (EMS)
Authors: Pratt Mark. D. 
Published: December 2007

Abstract
The purpose of this paper is to relate the experiences and lessons learned by the Abu Dhabi Company for Onshore Oil Operations (ADCO) as we have been developing our Environmental Management System (EMS) over the last two years. The opinions expressed in this paper are mine as Environmental Protection Advisor for ADCO. I have made several suggestions that I hope can help EMS implementation in similar companies just beginning the process.
ADCO is the largest of the Abu Dhabi National Oil Company (ADNOC) Group companies and is responsible for exploring and producing the onshore crude reserves in Abu Dhabi Emirate. ADCO consists of five major producing fields (Bab, Asab, Sahil, Shah and Bu Hasa) located in desert environments and the Jebcl Dhanna tank farm and shipping terminal located adjacent to a natural port on the north-western coast of Abu Dhabi. We are also beginning to develop and appraise some of our coastal-lying concession areas. ADCO's operations and therefore responsibilities begin at the seismic phase and extend to drilling, completion, production, gas/oil/water separation and pipelining of the crude to our storage and shipping terminal. Most associated gas produced in our fields is processed by our sister company, GASCO.
In 1994, ADCO senior management made a strong and visible commitment to improve the Company's environmental performance by expanding its Environmental Protection Group (EPG), retaining an experienced environmental consultant to perform an environmental baseline survey of the entire ADCO operation and authorising early development of an EMS to manage the ADCO environmental programme.
Prediction of Two-Phase Flow Through Chokes for Middle-East Oil Wells
Authors: Elgibaly A. A. M. , Nashawi I. S. 
Published: December 2007

ABSTRACT
Accurate prediction of multi-phase flow through chokes is required for modem production design and optimization of oil well performance. Most of the Middle-East oil wells are uniquely characterized with high production rates. Several correlations that relate the choke size with other variables involved in the multi-phase flow phenomena have been proposed in the literature. The validity of these correlations for Middle-East oil wells has been assessed in this study.
A new correlation has been developed to describe the choke performance of the Middle-East oil wells. The proposed correlation is similar to the Omana-type correlations based on dimensional analysis. This correlation was examined against a wide range of well test data collected from various oil fields in Egypt, Kuwait, Libya, and other Middle-East countries. Statistical analysis was used to compare the accuracy of the results obtained from the new correlation with those from other correlations. The effect of different PVT correlations on the predictive accuracy of the fluid flow equations has been also investigated. These properties included the surface tension of the gas/oil system, gas compressibility factor, solution GOR, and oil volume factor.
The developed correlation provided highly accurate results compared to the other existing correlations. This correlation is applicable for critical flow conditions and requires knowledge of the PVT data. This study showed that the use of different PVT correlations resulted in slight variation in the accuracy of the developed correlation.
Further analysis has been conducted in the present study on the Gilbert-type empirical correlations. Results emphasized the linear relationship between flow rate and upstream pressure for critical flow.
Delineation of Organic Richness and Thermal History of the Lower Cretaceous Thamama Group, East Abu Dhabi: A Modeling Approach for Oil Exploration
Authors: Taher Ahmed A. 
Published: December 2007

Abstract
The source rocks of the Lower Cretaceous Thamama Group in east Abu Dhabi were identified by using wireline logs. This technique was applied to 33 wells which provided a well-sampled new regional pattern of source rock distribution and thickness. The Tharmama Group includes rich source rocks in the Aptian Shu'aiba intra-shelf basin facies and a moderate source rock potential in the dense layers, especially those in the basal part of the Nasr Formation. The reconstruction of the burial and thermal histories indicates that the mature Thamama kitchens are mainly located in the eastern part of Abu Dhabi, adjacent to the foredeep basin and reached optimum maturity levels starting in the Eocene. Westward migration from these kitchens is mainly lateral and updip toward the main Thamama producing fields in central Abu Dhabi. The conclusion that the hydrocarbons migrated laterally is supported by oil to source rock correlation and the vertical distribution of hydrocarbons in the reservoirs.

INTRODUCTION
The Lower Cretaceous Thamama Group of eastern Abu Dhabi (Figure 1) includes several important hydrocarbon reservoirs. This sequence was deposited on a carbonate platform and varies in thickness from 2,500 to 3,000 feet (ft). The overlying Middle Cretaceous Nahr Umr shale and the basal part of the Nasr Formation are regional seals (Figure 2). Local seals also occur as intercalated dense carbonate layers.
Variable Rate Pressure Drawdown Analysis for Gas Wells
Authors: Nashawi I S. , Elgibaly A. A. M. 
Published: December 2007

ABSTRACT
Pressure transient tests of gas wells, in general, are peculiar in their nature. They possess additional degree of difficulty when compared with the oil well tests. The peculiarity of gas well tests over oil well tests is due to the non-linearity of the diffusivity equation and to the presence of non-Darcy flow or rate-dependent skin effect around the wellbore. Moreover, the constant flow rate requirement in conventional pressure drawdown tests adds another dimension of difficulty to the tests, because this condition is hard to fulfill in field applications.
In recent years, several approaches have been proposed to solve these problems. For instance, normalized pseudopressure and pseudo-time have been used to linearize the diffusivity equation. Variable rate tests were proposed as an effective substitute for single point test. Trial-and-error procedure or at least two constant rate tests were used to determine the rate-dependent skin. Even though the trial and error procedure and the two rate tests provide good estimates of the non-Darcy skin, they are time consuming and hard to apply in practice.
This paper presents a simple technique to analyze variable flow rate data of gas wells with turbulence and damage. The proposed method uses normalized pseudo-variables to avoid the non-linearity in the diffusivity equation and it is straight-forward in the sense that it does not require a trial-and-error procedure or two rate tests. The method involves the construction of two different plots. The formation permeability is obtained from the slope of the first plot, whereas the inertial turbulent flow coefficient and the mechanical skin factor are obtained from the slope and intercept of the second plot.
The proposed method is simple and provides accurate and reliable results in a short testing period when compared with other methods. A field case and a simulated example are used to illustrate the applicability of the proposed method.
A Fully Implicit, Three-Dimensional, Two-Phase, Control-Volume Finite Element Model for the Simulation of Naturally Fractured Reservoirs
Authors: Naji Hassan S. , Kazemi Hossein 
Published: December 2007

Abstract
This paper describes the formulation and application of a fully implicit, three-dimensional, two-phase (water and oil) mathematical model for the simulation of naturally fractured reservoirs. The model equations are discretized using the control-volume finite element (CVFE) scheme where pressure terms are treated in a finite element manner while mobility terms are upstream-weighted as in the usual finite difference (FD) method. The form of the discretized equations is similar to the usual FD method, thus standard techniques are used to solve the Jacobian. The equations are solved fully implicit for pressure, saturation, and wellbore variables using the iterative Newton-Raphson method of solution.
Two field scale examples, that were first presented by Kazemi et al., were used to test the model. These include a quadrant of a five-spot pattern, and a five-well fractured reservoir having dip and natural water influx.
Physical and Chemical Performances of Fiberglass Tubulars in Super Critical Application of CO2
Authors: Arian G. Hossein 
Published: December 2007

Abstract
Long term chemical and physical performance of aliphatic amine cured fiberglass Tubulars in high pressure super critical application of CO2 in both cyclic and static conditions have been investigated. No physical or chemical degradation was detected at the selected test condition of 2300 PSI and 120 F of carbon dioxide in cyclic or static conditions. Further analysis suggests a slow rate of CO2 penetration into the amine cured epoxy laminate. The failure mechanism model developed and presented here suggest a predictable failure based on stress due to pressure and temperature. The verification of the model presented paves the way for major simplification and cost reduction potentials in future construction and extension of a CO2 WAG Piping Systems, by combining CO2 and water injection lines into one.

Introduction
Carbon Dioxide (CO2) injection is being used commercially to produce oil that normally would be unrecoverable. CO2 is injected in the super critical state at a surface pressure of about 1500 to 2500 PSI. "CO2 is an efficient injectant because it dissolves readily in both oil and water, with CO2 solubility increasing with increasing pressure. The dissolution of CO2 in oil increases or swells the crude volume and decreases the crude viscosity, which results in a more mobile oil bank and improved sweep efficiency." (Reference 1).
Generally, in order to prevent channeling and maximize flood profitability, implementation of water alternating gas (WAG) injection becomes necessary. The CO2 WAG systems increases corrosion concerns drastically due to formation of carbonic acid and the contamination of produced water used for re-injection for metallic tubulars.
With a proper selection of raw materials, outstanding results have been achieved in the past 25 years using fiberglass tubulars in low pressure or low concentration applications of CO2 to combat corrosion problems. However, a few initial set backs in the early 80's, due to improper raw material selections, connection integrity, misapplication, or pure mishandling of the product, kept the usage of FRP Tubulars to a few selected projects for high pressure CO2 WAG Systems. The information presented here is intended to provide a reliable and predictable failure mechanism to facilitate selection and operation limitation of FRP Tubulars for a trouble free corrosion controlled high pressure CO2 WAG Piping System.