bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Fresh Look at Thin-bed Prospectivity Within Conventional Shallow Water Clastic Plays; Implication for Significant Bypassed pay
Authors: Dashti Rouhollah , Basu Debnath , Dahlan Athirah , Kyi Ko Ko 
Published: March 2015

Abstract
Thin-bedded sands in shallow water clastic deposits are widely neglected as exploration targets simply due to conventional wisdom that focuses more on the "charismatic" blocky clean sand packages. In addition, the lack of a strong, characteristic motif on the log response and complexity in quantitative characterization of these thinly laminated sequences leads to even less attention to such sequences as potential targets. This can have significant impact on the certainty of realistic reserve calculation in exploration and development planning in regions such as Southeast Asia where these thin-bedded sands are a considerable portion of the stratigraphic column.
This study has two phases; in the first phase, a novel technique is presented to identify and quantify thin sand laminations using borehole images and core. Both borehole image and core data is converted to binary data representing shale and sand facies. Then these images are used to quantify the total thickness of thinly-laminated sands on the basis of specific cutoff values. In the second phase, a comprehensive analysis of a local present-day analogue determines the possible hydrocarbon storage capacity of thin-bedded deposits. This is accomplished through an area/volume approach. In this approach, after locating the pertinent locality within the depositional environment that can be considered as the equivalent to the subsurface section under study, the sand volume vs. area of thin-bedded heterolithic facies is computed. This is used to estimate the storage capacity of these facies at the field-scale. Additionally, the storage capacity is compared to the capacity of channel-fill sands as conventional targets in the same setting.
Results of this study show that the new technique using high-resolution borehole images can successfully identify and quantify thin-bedded sands, and results have an excellent match with core data. Also, the core results confirm that these deposits have sufficient reservoir quality (porosity and permeability), particularly for gas production. This work demonstrates that, contrary to conventional belief, the storage capacity of thin-bedded sands can be significantly high and sometimes may even exceed that of blocky channel or mouth-bar sands. This implies that substantial quantities of pay are continuously bypassed in basins where these sequences are expected.

Introduction
Hydrocarbon accumulations in thin-bedded reservoirs constitute a significant part of many newly discovered fields. These are predominantly deepwater turbidite prospects, which lack thick, readily-recognizable sand packages and require much effort in thin-bed reservoir analysis. However, similar types of sediments often occur in many other depositional settings, including coastal and shallow water environments. The impact of thin beds on hydrocarbon pore-thickness has been well documented in tidal environments as well (Passey et al. 2006; Fig. 1).
Helium 2 - A New Dimension to Energy Resources
Authors: Al-Harbi Marwan 
Published: March 2015

Abstract
Qatar is destined to be the world's largest helium exporter by 2013 when the world's largest helium refining unit begins to produce its first drop of liquid helium. The new unit Helium 2 facility will join the existing Helium 1 facility to provide more than a quarter of worldwide helium sales.
On behalf of RasGas and Qatargas owners, the RasGas and Qatargas Helium 2 Project Teams have built a state-of-the-art facility where crude helium is extracted from six Liquefied Natural Gas (LNG) mega trains. Crude helium is transported by pipeline to a helium recovery unit, refined to 99.999 percent Grade-A purity, liquefied, and loaded into containers for shipment to three main customers. The new extraction facilities will also include equipment to oxidise trace amounts of methane from the feed stream in order to minimise the project's environmental footprint.
Qatar's helium is produced as a by-product from the LNG trains. Capitalising on economies of scale, large volumes of helium are extracted for export, further strengthening the market position of the project's shareholders and providing flexibility to meet future demands.
Helium is used in various applications such as medical scanners, academic laboratories, diving, space exploration, and leak detection. In cryogenic applications where extremely low temperatures are required, there are no known substitutes for helium, making it a strategic long-term resource.
Two Strategies for Attenuating Internal Multiples in Land Data
Authors: Retailleau M. , Shorter J. , Farran H. , Hugonnet P. , Wa Hong T. , Benjamin N. , Pica A. 
Published: March 2015

Abstract
Two new internal multiple attenuation methodologies are presented. The first approach uses a 3D wave equation based multiple modeling technique followed by 3D adaptive subtraction. The recorded data are back propagated/propagated through a reflectivity model (obtained from a preliminary migration) of the overburden. All possible multiple raypaths are modeled by using different combinations of two sub-windows in this reflectivity model. Each combination results in a specific multiple model. The generated multiple models are then simultaneously adapted and subtracted from the input data. The second approach is a 3D dip extraction and filtering technique, taking advantage of any dip discrimination between the primaries and multiples. It works on post stack and pre stack volumes. We show how the two methods are complementary and how they can be combined.
The first approach can be applied to any seismic data plagued with strong internal multiples and is perfectly adapted to modern dense, wide azimuth surveys. The second approach works on any seismic volume in which multiples and primaries have different dips in a given domain.
Some real data examples from South Oman 3D seismic datasets are shown. All are characterized by a heavy multiple contamination, generated by strong shallow reflectivity sequences in a flattish overburden, and overlying deeper, weaker and heavily structured primaries. By revealing structures previously invisible, these techniques add a lot of value to existing seismic data sets.
The generation mechanism of internal multiples is often quite complex making them difficult to predict. The main benefits of the methods described here are that they work in absence of move out discrimination and without the need of a precise identification of the internal multiple generators.

Introduction
In some areas of Middle East, it is common to have shallow carbonate sequences with strong reflectivity, high velocity contrasts, overlying lower reflectivity clastic series with weak impedance contrasts and lower velocities. This geologic sequence yields a heavy contamination of the lower unit by energetic interbed multiples generated in the upper unit ("curtain of multiples"). These multiples often have the same, or higher apparent velocity, than the primaries, offering no opportunity to remove them by move-out discrimination. Similarly, prediction methods (gapped deconvolution) have proved unsatisfactory. And in addition, it is mostly impossible to identify clearly the generators, given the large number of possible candidates.
Historically these unwanted multiples have been removed by surgical 3D FK filtering after flattening of the suspected multiple generators. This method has been used for many years but has several strong limitations, in addition to the well known FK artifacts. Hence new methodologies were required to overcome the failings of this 3D FK approach.
From a Project-oriented to an Operations-focused organization - The case of QG OPCO Well Engineering and Intervention Division
Authors: Paez Tomas J 
Published: March 2015

Abstract
Qatargas (QG) OPCO experienced an impressive growth in the last 6 years, starting with QG2 in 2006, and followed by QG 3&4, QG1 first in-fill drilling campaign, and finally QG1 second in-fill drilling campaign in 2012. These projects helped QG OPCO become the biggest LNG producer in the world. The sudden expansion did not allow the Well Engineering and Intervention (WEI) Division to easily assimilate the changes. Even though WEI grew in size (i.e. number of personnel) by recruiting global talent, this accelerated growth demanded a different approach to develop organizational capabilities (resources and processes) to operate the new well count.
In 2012, WEI embarked on multiple initiatives to transition from a Project-oriented to an Operations-focused organization. The first initiative was related to the need for one overarching Well Integrity Management System since different criteria and procedures were utilized in each of the ventures. The second initiative addressed the need for a Well Control and Blowout Prevention Manual and Contingency Plan to prevent and mitigate well control situations in scenarios where Jack Up availability and Drilling organizations were limited (drilling organizations set up to expand QG OPCO were reallocated, downsized or dismantled). In addition, a new WEI structure was required in order to gain efficiencies, align personnel with business needs, and sustain or develop capabilities in the workforce.
This paper discussed the journey of WEI in pursuing organizational capabilities in order to meet ever-demanding global energy challenges and QG OPCO vision - to be the world's premier LNG Company.

Introduction
The North Field, discovered in 1971, is the largest non-associated gas field in the world with estimated reserves exceeding 900 TCF. Qatargas is one of the four companies operating in the North Field. Since Qatargas establishment in 1984, the State of Qatar has become the biggest LNG producer in the world, providing reliable energy security globally and operating the biggest LNG shipping company internationally. Today, Qatargas is the largest LNG producing company in the world. Its role in producing North Field resources has a significant impact on the State of Qatar and the global LNG markets.
Systematic Evaluation of Asphaltene Formation Damage of Reservoir Fluids from Lake Maracaibo, Venezuela
Authors: Memon Afzal , Borman Craig , Garcia Martha , Reyes Tristancho Dayana Judith , Ratulowski John , Gao Jinglin 
Published: March 2015

Abstract
One of the most concerning areas for asphaltene deposition is the near-wellbore region, where such deposition causes formation damage. The reservoir fluid of the Lake Maracaibo region is known to experience operational problems due to asphaltene deposition inducing production losses. A detailed asphaltene formation damage investigation was performed on the live oil samples from the Lake Maracaibo area. An unusual asphaltene precipitation envelop was observed for this fluid and reported in an earlier publication (Gonzales et al., SPE 153602, 2012). In the current paper, we focus on the systematic evaluation of asphaltene formation damage using stacked composite core samples.
A special coreflood system was designed for an asphaltene formation damage study using reservoir core samples and sour-live reservoir fluid samples. The effect of flocculated asphaltene in the porous media was evaluated as the reservoir pressure decreases below the asphaltene onset pressure (AOP). Live samples were collected and flooded through the stacked composite core plugs under reservoir conditions. Progressive pressure reductions were performed to induce asphaltene precipitation in the porous media. Oil permeability changes were measured to evaluate the effect of this phenomenon in the reservoir using composite core. Significant impairment of composite core was caused by the depressurization of the reservoir fluid below AOP. The inlet pressures of the composite core stack were maintained just above AOP and the outlet pressure approximately 50 psi above saturation pressure throughout the core flood experiment. Thus, asphaltene precipitation onset occurred inside the composite core.
This experiment showed significant permeability loss in the composite core after sufficient flooding of live oil fluid. Following the core flood experiment, the core stack was depressurized, and the remaining hydrocarbon was extracted from individual core plugs. Detailed chemical analyses were performed on the extracted hydrocarbon deposits from individual core plug with various analytical techniques, such as asphaltene content, simulated distillation, optical density, and thin-section analysis. These analyses' results confirmed that the observed oil permeability loss was indeed due to the formation of asphaltene deposit inside the porous media, and the asphaltene deposition was somewhat more extensive in the tighter core sections.
How to Manage CT operations in Hostile environment: Field Case Studies on CT Challenges in Deep HPHT High Sour Carbonate Formations.
Authors: Packirisamy Packirisamy , Al-Bader H. , Al-Salali Y. , Vidyasagar Vidya Sagar , Manimaran A. , Al-ibrahim A. R. , Rajkhowa A. 
Published: March 2015

Abstract
Objective of this paper is to present our recent case-histories involving uncommon and unexpected Coiled Tubing (CT) intervention challenges in exploratory wells while testing and stimulating deep HPHT high Sour carbonate formations.
Jurassic formations at around 17,000 feet in Kuwait are tested using cased-hole Drill Stem Testing (DST) system. 15K CT is employed during DST for displacement of kill fluids to achieve under balance prior to perforation, placement of acid for stimulation and for well killing operations. CT operational challenges encountered during testing deep exploratory wells are high pressure reservoir(&gt;10,000 psi), limit on CT injection pressure&gt;10,000 psi, pumping acid of 28% HCL, sour well fluid, salt plugging, etc. Well intervention under such challenging conditions requires proper planning, right equipment, techniques and procedures to ensure safe operation. Existing challenging conditions were well managed and objectives were met.
A new problem of formation solids production after acidization of Kerogen rich carbonate/shale formation created a new challenge for CT operations which is unlike the common problem of sand production from the unconsolidated sand stone formation. In some wells, DST string got plugged with solids after acid stimulation and obstruction/stuck-up was encountered while operating CT. Another unexpected problem is the high H2S concentration of 35% in the recently discovered field. The unexpected challenges created unwarranted situation. It is a challenging task for operators to execute the safe and successful CT operations under these uncommon and unexpected conditions. Initially, even some of the service companies expressed their inability to operate CT under these extreme conditions.
The unexpected problems are managed well within the available resources and the well test operations were executed safely and successfully. The new solids production operational experience has helped the operator to avoid the reoccurrence of CT stuck up thereby decrease the operational risk and increase the success rate. It has been proved practically in the field that CT can safely be utilized in high sour wells up to 35% H2S and increased the operator confidence.
The experience gained, new challenges encountered, safe practices followed and way forward for execution of successful coiled tubing intervention in hostile environment will be discussed in this paper.
Proactive Casing Leak Detection Methodologies: A Case History
Authors: Al-Khamis Mohammed N. , Al-Yateem Karam , Kima Enow A. 
Published: March 2015

Abstract
This paper addresses how high resolution electromagnetic induction was used to study, assess and map the overall well casing integrity of offshore wells and to enable predictions of casing leakage based on the extent or severity of the casing corrosion log. The objective of the paper is to show how proactive detection and prevention of leaks before they occur have guaranteed continuous operation excellence, safety and environmental compliance.
These studies were carried out to understand the nature of the corrosion observed. In addition, several other technologies were deployed to effectively detect leaks and further sketch out their location. The lessons learnt and experience acquired during the monitoring and evaluation of casing integrity will be shared.
The new technology was used as a tool to establish a casing integrity baseline for an entire field and articulated the new strategic corrosion master surveillance plan. Using the new technology has resulted in a significant reduction in the frequency of routine conventional temperature surveys and therefore optimized resource utilization to foresee other essential jobs.

Introduction
Issues associated with casing leaks can lead to significant losses of oil or gas reserves as well as momentous pollution problems. Therefore, early detection of the leaks as soon as they occur is very crucial. In Saudi Arabia oil fields, casing leaks are of particular importance since the country holds some of the largest reserves of petroleum in the world1. The problem is of variable severity from one field to another, depending on the conditions encountered. The sensitivity increases when the field is mature.
A thorough investigation of all factors — influencing the life of the casing — and their correlation with field data has been conducted for a particular field. In addition, over the years engineers have improved their detection techniques. In this paper, the effect of all factors influencing the life of the casing and casing leak detection methods used are discussed.
Safety, asset integrity, monitoring, detection and possible maintenance and/or repairs of leaks as a result of corrosion are paramount. The conventional technology to detect leaks is the temperature survey, which identifies either up flow or dumping leaks. The method is executed on quarterly basis to identify any casing leaks in a timely manner. If the temperature profile is suspicious, well head samples are collected to carry out further investigation and testing. Annuli survey is conducted bi-annually in addition to temperature survey.
This average production casing life has improved with the new proactive approach to monitor and maintain the integrity of production casing in the field. Other practices that help enhance the strategy include improving cementing practice, selecting chrome 13 casing types across corrosive aquifers, and completing new and workover wells with tubing downhole packers to isolate and protect potable aquifer water from contamination.
Enhanced Reservoir Characterization with Horizontal Well Logs in Dukhan Field, Qatar
Authors: Al-Naama Abdulla , Al-Sahlawi Adel , Stanley Rowan , Albotrous Hilal , Ekamba Blaise , Guo Pingjun 
Published: March 2015

Abstract
Over the last decade, horizontal drilling has played a significant role in the development of the Dukhan field in Qatar. Optimal placement of high-angle and horizontal wells has ensured economic hydrocarbon production in the Arab oil reservoirs. In the Arab C reservoir interval, stratigraphic layers are generally thin and exhibit a high degree of lateral variation in rock properties and low to medium permeability. Horizontal producers with long lateral sections have increased ultimate recovery by providing greater penetration of oil columns above oil water contacts and by tapping attic oil and isolated reservoir compartments. Sweep efficiency has also been improved through horizontal well waterflood programs.
Advances in rotary steerable drilling and logging-while-drilling (LWD) technologies for horizontal wells provide new types of data that can be used for improved reservoir characterization and geologic modeling. LWD sensors are used at Dukhan to acquire real time petrophysical measurements and LWD image logs are now routinely acquired along with conventional triple combo logs (density/neutron/resistivity). A specialized workflow was developed to utilize the LWD image data in log interpretation. This workflow consists of interpretation modules that can be used to define formation bed boundaries and quantify formation property variations along horizontal wellbores. These definitions of 3D bedding structure data and formation properties are then used to condition the geologic model structure and update cell properties.
Image logs and petrophysical interpretation results from several horizontal wells will be presented. Comparisons with offset vertical wells are made to illustrate the added value of using horizontal well data in reservoir characterization. Significant uplift in geological modeling is also achieved by incorporating lateral property variation identified through horizontal well petrophysical evaluations.

Introduction
Dukhan Field, discovered in 1939, is one of the major oil fields in the Middle East region. The first discovery wells were based on field mapping of the Dukhan anticline (Trabelsi et al., 2009, Stephens et al., 2009). The field forms a north to southeast trending anticline that is 70 km long and 8 km wide (Figure 1A). The anticline culminates in four distinct domes, which roughly correspond to the major divisions of the field. These are, from north to south, the Khatiyah, Fahahil, Jaleha, and Diyab sectors (Figure 1B). A series of extensive studies have been done to characterize the environments of deposition and to define a consistent sequence stratigraphic framework (Figure 2). Production of the Arab C and D reservoirs started in 1949 and has progressed through various phases of the oil field development.