Successful Mitigation of Excessive Backreaming in Troublesome Vertical Applications in the Sultanate of Oman

2021 ◽  
Author(s):  
Ananda Pravana ◽  
Humaid Ali Hassan Albalushi ◽  
Zakaria Mamari ◽  
Badar Al Zeidi ◽  
Tom Newman ◽  
...  
Keyword(s):  
Sultanate Of Oman ◽  
Shale Formations ◽  
Delivery Times ◽  
Methodical Approach ◽  
Bottom Hole Assembly ◽  
Design Characteristics ◽  
Drive Systems ◽  
Time Required ◽  
Gas Fields ◽  
Record Section

Abstract Drilling through some of the reactive shale formations in the western gas fields in the Sultanate of Oman has proven challenging and often troublesome. Frequently, time spent on backreaming would exceed the time required to drill the related hole sections. In addition, the carbonate Natih sequence has also proven problematic. High levels of vibrations are often encountered. Such drilling dysfunctions are known to be destructive to both bit and bottom hole assembly (BHA). Different mud systems, drive systems and reamer types were used in separate attempts to alleviate the faced dysfunctions to little avail. This paper illustrates a trial campaign introducing an alternative design stabilizer (ADS) and reamer (ADR) to the drilling BHA with the aim of addressing and resolving the aforementioned limiters. Based on a set of agreed-on key performance indicators (KPIs), and following a methodical approach, a 4-well trial was conducted in order to introduce a unique stabilizer-reamer design while simultaneously scrutinizing and optimizing the BHA configuration accordingly. Two of the candidate wells targeted the 17-1/2" section while the other 2 wells targeted the 12-1/4" sections. The main goals were to reduce the time spent on backreaming by 50% and minimize the experienced levels of vibrations in order to extend bit runs and reliability of the different BHA components. For further comparisons, the same approach was tested on a rotary BHA as well as a steerable motor BHA in the larger hole sections. Both 17-1/2" sections were each drilled in a single run similar to the second 12-1/4" section. The first 12-1/4" also proved smooth and required 2 runs due to bit hours, still noting a record section distance run for a single bit. All BHAs were optimized around the placement of the new design stab and reamer design combination. The optimized BHA configuration enabled pulling out of hole (POOH) on elevators for all 4 sections almost fully eliminating the hard backreaming experienced in past wells. In addition, it was also noted that in all cases the levels of vibrations were significantly reduced compared to what is typically experienced and recorded in the offset wells. This enabled a record setting bit run for that particular section and field. The authors detail the historical challenges encountered drilling such wells then present the applied benchmarking exercise and the adopted systematic approach to tackle those challenges. Following, the unique design characteristics of the deployed technology are highlighted and how this is applied in each of the runs in view of optimizing casing point to casing point section delivery times. Finally, the achieved results and gains are underlined together with a roadmap forward.

Revision of Pressure Transient Analysis in Mature Condensate-Rich Tight Gas Fields in Sultanate of Oman

2022 ◽  
Author(s):  
Ahmed Elsayed Hegazy ◽  
Mohammed Rashdi
Keyword(s):  
Transient Analysis ◽  
Horizontal Wells ◽  
Development Planning ◽  
Reservoir Modeling ◽  
Sultanate Of Oman ◽  
Pressure Transient Analysis ◽  
Pressure Transient ◽  
Full Field ◽  
Gas Fields ◽  
Half Length

Abstract Pressure transient analysis (PTA) has been used as one of the important reservoir surveillance tools for tight condensate-rich gas fields in Sultanate of Oman. The main objectives of PTA in those fields were to define the dynamic permeability of such tight formations, to define actual total Skin factors for such heavily fractured wells, and to assess impairment due to condensate banking around wellbores. After long production, more objectives became also necessary like assessing impairment due to poor clean-up of fractures placed in depleted layers, assessing newly proposed Massive fracturing strategy, assessing well-design and fracture strategies of newly drilled Horizontal wells, targeting the un-depleted tight layers, and impairment due to halite scaling. Therefore, the main objective of this paper is to address all the above complications to improve well and reservoir modeling for better development planning. In order to realize most of the above objectives, about 21 PTA acquisitions have been done in one of the mature gas fields in Oman, developed by more than 200 fractured wells, and on production for 25 years. In this study, an extensive PTA revision was done to address main issues of this field. Most of the actual fracture dynamic parameters (i.e. frac half-length, frac width, frac conductivity, etc.) have been estimated and compared with designed parameters. In addition, overall wells fracturing responses have been defined, categorized into strong and weak frac performances, proposing suitable interpretation and modeling workflow for each case. In this study, more reasonable permeability values have been estimated for individual layers, improving the dynamic modeling significantly. In addition, it is found that late hook-up of fractured wells leads to very poor fractures clean out in pressure-depleted layers, causing the weak frac performance. In addition, the actual frac parameters (i.e. frac-half-length) found to be much lower than designed/expected before implementation. This helped to improve well and fracturing design and implementation for next vertical and horizontal wells, improving their performances. All the observed PTA responses (fracturing, condensate-banking, Halite-scaling, wells interference) have been matched and proved using sophisticated single and sector numerical simulation models, which have been incorporated into full-field models, causing significant improvements in field production forecasts and field development planning (FDP).

scholarly journals A New Analysis Model for Potential Contamination of a Shallow Aquifer from a Hydraulically-Fractured Shale

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3010
Author(s):  
Weihong Peng ◽  
Menglin Du ◽  
Feng Gao ◽  
Xuan Dong ◽  
Hongmei Cheng
Keyword(s):  
Migration Time ◽  
Shallow Aquifer ◽  
Contaminant Migration ◽  
Analysis Model ◽  
Shallow Aquifers ◽  
Shale Formations ◽  
Migration Mechanism ◽  
Shale Reservoirs ◽  
Time Required ◽  
The Impact

Hydraulic fracturing (HF) is widely used in shale gas development, which may cause some heavy metals release from shale formations. These contaminants could transport from the fractured shale reservoirs to shallow aquifers. Thus, it is necessary to assess the impact of pollution in shallow aquifers. In this paper, a new analysis model, considering geological distributions, discrete natural fractures (NFs) and faults, is developed to analyze the migration mechanism of contaminants. Furthermore, the alkali erosion of rock caused by high-pH drilling of fluids, is considered in this paper. The numerical results suggest that both NFs and alkali erosion could reduce the time required for contaminants migrating to aquifers. When NFs and alkali erosion are both considered, the migration time will be shortened by 51 years. Alkali erosion makes the impact of NFs, on the contaminant migration, more significant. The migration time decreases with increasing pH values, while the accumulation is on the opposite side. Compared with pH 12.0, the migration time would be increased by 45 years and 29 years for pH 11.0 and 11.5, respectively. However, the migration time for pH 12.5 and 13.0 were found to be decreased by 82 years and 180 years, respectively. Alkali erosion could increase the rock permeability, and the elevated permeability would further enhance the migration velocity of the contaminants, which might play a major role in assessing the potential contamination of shallow aquifers.

Standardized Development Planning for Satellite Fields in the South of the Sultanate of Oman

2021 ◽  
Author(s):  
Peter in ‘t Panhuis ◽  
Adel El Sabagh ◽  
Hilde Coppes ◽  
John Meyers ◽  
Niels Van der Werff ◽  
...  
Keyword(s):  
Development Strategy ◽  
Early Stage ◽  
Development Planning ◽  
Oil Fields ◽  
Sultanate Of Oman ◽  
The South ◽  
Well Design ◽  
Time Required ◽  
Rule Based Approach ◽  
Petroleum Development

Abstract This article will show how a standardized rule-based approach was used by Petroleum Development Oman (PDO) to shorten the cycle time required to mature the opportunity of implementing waterflood developments in small-to-medium sized satellite oil fields in the South of the Sultanate of Oman. The standardized concept relies on a common development strategy for a portfolio of satellite fields with similar reservoir and fluid characteristics that are still under depletion or in the early stage of waterflood. The targets are early monetization, driving cost efficiency through standardization & replication, and increasing recovery factor through the accelerated implementation of field-wide waterflood. This is achieved by leveraging excess capacity in existing facilities, applying analytical workflows for forecasting, standardizing well design and urban planning, and by applying the learnings and best practices from nearby fields that already have mature developments.

On the Drive Systems for High-Performance Machines

1984 ◽  
Vol 106 (1) ◽  
pp. 102-108 ◽  
Author(s):  
K. A. Pasch ◽  
W. P. Seering
Keyword(s):  
High Performance ◽  
Mechanical Constraints ◽  
Transmission Mechanisms ◽  
Angular Velocities ◽  
Drive Systems ◽  
Time Required

The choice of actuators and transmissions in high performance machines and manipulators can have a profound effect on the time required for a specified machine task. For systems operating with mechanical constraints, such as limits on allowable angular velocities in motors, designing for greatest achievable acceleration will not always minimize move time. In this paper the effects on performance of ranges of choices of actuators and transmission mechanisms are evaluated, and guidelines for choosing the optimal drive elements are presented.

HORIZONTAL DRILLING IN AUSTRALIA: THREE CASE HISTORIES

1991 ◽  
Vol 31 (1) ◽  
pp. 354
Author(s):  
Russell McNicoll
Keyword(s):  
Oil And Gas ◽  
Design Parameters ◽  
Horizontal Drilling ◽  
Assembly Design ◽  
Oil And Gas Fields ◽  
Bottom Hole ◽  
Directional Control ◽  
Bottom Hole Assembly ◽  
Gas Fields ◽  
Drilling Time

Three horizontal wells with horizontal sections of up to 331 m were drilled successfully during the development of the marginal North Herald and South Pepper oil and gas fields, which have relatively thin oil columns (6 to 12 m) at a depth of some 1200 m sub-sea. A steerable motor system was used to maintain directional control within the design parameters. This system proved to be successful from the start and no major changes to the bottom hole assembly design were required to drill all the wells. Average drilling time including running and setting the seven inch liner amounted to 12 days. The wells were tested with rates up to 7500 BOPD through a one inch choke.

A Procedure for Rapid Issue of Red Cells for Emergency Use

2005 ◽  
Vol 129 (4) ◽  
pp. 492-496
Author(s):  
Richard B. Weiskopf ◽  
Mary Webb ◽  
Deena Stangle ◽  
Gunter Klinbergs ◽  
Pearl Toy
Keyword(s):  
Red Blood Cells ◽  
Operating Room ◽  
Blood Cells ◽  
Blood Bank ◽  
Red Cells ◽  
University Hospital ◽  
Delivery Time ◽  
Delivery Times ◽  
The Times ◽  
Time Required

Abstract Context.—A College of American Pathologists Q-Probe revealed that the median turnaround times for emergency requests for red blood cells from the operating room were 30 minutes to release of cells from the blood bank and 34 minutes to delivery to the operating room. These times may not be adequate to permit the red cells to provide sufficiently rapid delivery of oxygen in massively bleeding patients. Objective.—To improve the time from emergency request for red cells to delivery to the operating room. Design.—A new emergency issue program was implemented for only the operating rooms; emergency issue to all other hospital locations remained unchanged. Six units of group O Rh-negative red blood cells (RBCs) are maintained in the blood bank in a separate basket with transfusion forms containing the unit numbers and expiration dates and a bag with one blood tubing segment from each unit. The times to issue and to delivery to the operating room suite were compared with time to issue of 2 group O Rh-negative RBCs for other hospital locations using the older system during the same time period and with the time to issue of 2 units to all other hospital locations during the preceding 2 years. Setting.—A university hospital. Main Outcome Measures.—Time between emergency request for red cells and delivery to the operating room. Results.—The time between blood bank notification and arrival in the operating room of the 6 units of RBCs was significantly shorter than the time required to just issue (not including delivery time) 2 units of RBCs to other hospital locations. With the new procedure, 82% of units issued reached the operating room within 2 minutes of request, 91% arrived within 3 minutes, and 100% arrived within 4 minutes. These percentages are significantly higher than those for only issue of blood (without delivery) using the older issuing procedure for all hospital locations during the previous 2 years (37%, 49%, and 66%, respectively; P = .007, .009, and .02, respectively) and for other locations during the same 7-month period (29%, 46%, and 73%, respectively; P = .004, .01, and .09, respectively). Time (mean [95% confidence interval]) from blood bank notification to delivery of RBCs to the operating room suite (2.1 [1.6–2.6] minutes, of which approximately 50–60 seconds is attributable to delivery time) was less than issue times (not including delivery times) using the older issuing procedure for other hospital locations during the same period (4.1 [3.1–5.0] minutes; P = .007). Conclusions.—An emergency issue procedure can be used to issue several units of RBCs within 1 minute and have them delivered to the operating room within 2 minutes while maintaining sufficient controls and providing required information to satisfy patient and blood bank requirements.

Effects of map design characteristics on users’ search performance and cognitive load

2019 ◽  
Vol 37 (4) ◽  
pp. 667-679 ◽  
Author(s):  
Hosam Al-Samarraie ◽  
Atef Eldenfria ◽  
Melissa Lee Price ◽  
Fahed Zaqout ◽  
Wan Mohamad Fauzy
Keyword(s):  
Cognitive Load ◽  
Brain Activity ◽  
Cognitive Activity ◽  
Search Performance ◽  
Brain Wave ◽  
Content Type ◽  
Eeg Data ◽  
Map Design ◽  
Design Characteristics ◽  
Time Required

Purpose This paper aims to investigate the influence of map design characteristics on users’ cognitive load and search performance. Two design conditions (symbolic vs non-symbolic) were used to evaluate users’ ability to locate a place of interest. Design/methodology/approach A total of 19 students (10 male and 9 female, 20-23 years old) participated in this study. The time required for subjects to find a place in the two conditions was used to estimate their searching performance. An electroencephalogram (EEG) device was used to examine students’ cognitive load using event-related desynchronization percentages of alpha, beta and theta brain wave rhythms. Findings The results showed that subjects needed more time to find a place in the non-symbolic condition than the symbolic condition. The EEG data, however, revealed that users experienced higher cognitive load when searching for a place in the symbolic condition. The authors found that the design characteristics of the map significantly influenced users’ brain activity, thus impacting their search performance. Originality/value Outcomes from this study can be used by cartographic designers and scholars to understand how certain design characteristics can trigger cognitive activity to improve users' searching experience and efficiency.

scholarly journals Geofluid dynamic concept of prospecting for hudrocarbon accumulations in the earth crust

2019 ◽  
pp. 79-91
Author(s):  
L. A. Abukova ◽  
Yu. A. Volozh ◽  
A. N. Dmitrievsky ◽  
M. P. Antipov
Keyword(s):  
Oil And Gas ◽  
Fluid Dynamic ◽  
Sedimentary Basins ◽  
Hydrocarbon Generation ◽  
Oil And Gas Fields ◽  
Migration Theory ◽  
Drainage Layers ◽  
Drive Systems ◽  
Lateral Drainage ◽  
Gas Fields

In our paper we produce new evidence of the tectonosphere and hydrosphere structure of oil and gas sedimentary basins and confirm significant influence of geofluid-dynamic processes on formation of hydrocarbon accumulations in the crust at the great depths. In our opinion the theory based on obsolete views on the tectonosphere structure lessen the importance the sedimentary migration theory of hydrocarbon generation. We prognosticate a particular stagnant type of post-elysionic water-drive systems in the crust at the great depths in conditions of increased hydrodynamic isolation. Absence of regionally sustained vertical and lateral drainage layers characterizes geological environment where stagnant type developed, and, corollary, fluids outflow into external environment is practically unfeasible. The subsalt filling complexes of the epicontinental deepwater basins are included into the post-elysionic water-drive systems. These complexes occur at the great depths and possibility of striking unique and large oil and gas fields there is inherent. We propose a system of fluid-dynamic conditions for preserving hydrocarbon accumulations in the lower crust as a result of developing sedimentary-migration theory for oil and gas formation. We consider the refinement of methods for prospecting and exploration large deposits at the great depths will pave the way for expanded reproduction of hydrocarbon reserves in the “old” oil and gas producing regions in our country.

New Generation of Formation Testers – New Horizons: First Experience in Russia

2021 ◽  
Author(s):  
Sergey Vasilevich Novikov ◽  
Mikhail Viktorovich Charupa ◽  
Yakov Eduardovich Dzhalatyan ◽  
Stanislav Sergeevich Kuzmin ◽  
Yermek Talgatovich Kaipov ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Geological Structure ◽  
Well Testing ◽  
Testing Platform ◽  
Testing Procedures ◽  
Measuring Surface ◽  
Order Of Magnitude ◽  
Hydrocarbon Fields ◽  
Time Required ◽  
Gas Fields

Abstract As the production of oil and gas in major regions has been declining, exploration efforts are shifting towards hard-to-reach understudied areas with lack of necessary infrastructure. In addition to that, hydrocarbon fields that are being explored today, typically have more complex geological structure than the ones discovered decades ago and are characterized by the presence of multiple reservoirs with individual fluid contacts. The abovementioned reasons cause significant increase in time required to test these reservoirs and estimate their production potential. Therefore, there is a real need for reliable technologies that would expedite the testing of such complex fields. New wireline formation testing platform has an updated hardware architecture enabling to use it for both traditional formations testing applications as well as the development of new testing procedures deviating from conventional practices. This paper describes the novel testing approach implying the use of wireline formation tester (WFT) in conjunction with a surface multiphase flowmeter, which was implemented at one of the large gas fields located on the Gydan peninsula. A key feature of the new formation testing platform compared to its predecessors is its ability to pump an order of magnitude greater volumes of reservoir fluids, which allows to estimate permeability in the uninvaded zone of the reservoirs and their productivity. Combination of the wireline formation tester with the surface multiphase flowmeter enables measuring surface rates and capture surface samples of reservoir fluids thus making this type of testing comparable to traditional well testing. At the beginning of the paper we provide a brief description of the acquired formation testing results with stress on key features of the new wireline formation testing platform. The rest of the paper is devoted to Deep Transient Testing (DTT), more specifically, to its design and planning, required hardware and description of results acquired during such tests. We also demonstrate an approach that can be used to estimate reservoir productivity based on the obtained data.

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