bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Application of In-fissure Divert Fracturing Technology in Ultra-low Permeability Oil Field
Authors: Song Zhenyun , Wang Xiaowen , Ren Yanpeng , Li Yong , Zheng Weishi 
Published: May 2016

Abstract
According to the geologic characteristic and development, performance of ultra-low permeability reservoirs, and oil-water distribution rules of reservoir, this paper puts forward the key points in improving the single well production of old oilfield—develop the "dead oil area", and forms supporting technologies of in-fissure divert fracturing which is suitable for ultra-low permeability reservoirs. The onsite experiments prove that the in-fissure divert fracturing technology can effectively improve old well production of ultra-low permeability reservoirs.

Introduction
Changqing oilfield is a typical low-permeability, low pressure, low-production reservoir. Water flood and fracturing are indispensable measures to improve single well production. With the deepening of oil field development, oil production continues to decline, water content increases, the oil field development problems are conspicuous. There are a large number of "dead oil area", and the oil-water relationship is complex. The conventional refracturing measures cannot develop the "dead oil area". The cost is high, but the economic effects are limited. Therefore, in-fissure divert fracturing technology is developed and applied. This technology has been applied in 700 wells and has effectively developed "dead oil area" and improved well production.
The necessity analysis of fracture reorientation in ultra-low permeability oil reservoir

Geological characteristics.
CI and CII oil layer of Triassic YI group is one of the mainly developed reservoirs for Changqing oilfield. Reservoir lithology is mainly arcose, which is a typical ultra-low premeability, low pressure, and low production reservoir. (See Table 1)
Meeting The Challenge Of Global Climate Change With Technology Innovation
Authors: Yang Yan , He Yan Qing , Rao Libo , Wang Jingmei 
Published: May 2016

Abstract
Global climate change is one of the serious problems faced by humankind in the 21st century. Developing policies and practices that tackle climate change without removing opportunities for growth and development has become one of the most significant challenges for governments and industry. The oil companies may contribute to the greenhouse gas control by developing low carbon energy, capturing, utilizing and storing carbon dioxide, continuously improving the energy efficiency and providing efficient products. To realize the greenhouse gas control goal, the need for technological innovation is dramatic and increasing. The companies are suggested to manage the relavant technologies in a strategic way, care and participate in the policy making and join the international network to accelerate the innovation process. The strategy, practice and technological innovation cases of CNPC in greenhouse gas control are introduced.

The challenge of global climate change
Global climate change is one of the serious problems faced by humankind in the 21st century. In particular, with increasing growth of fossil fuel (such as coal and oil) consumption, the emission of greenhouse gas (such as CO2) has kept growing.
According to the WEO (world energy outlook) 2008, in the Reference Scenario, rising global fossil-fuel use will continue to drive up energy-related CO2 emissions, from 28 Gt in 2006 to 41 Gt in 2020 - an increase of 45%. The Reference Scenario trends in world energy use put the world on course for the concentration of carbon dioxide (CO2) in the atmosphere to double from 380 parts per million in 2005 to around 700 ppm in the next century. Taking into account all greenhouse gases in all sectors, this would lead to a CO2-equivalent (CO2-eq) concentration of around 1 000 ppm, corresponding to a rise in global average temperature of up to 6°C, relative to pre-industrial levels.
There is a growing scientific consensus that anthropogenic greenhouse gases are driving detrimental climate change. If GHG emissions are not reduced to significantly below current levels within the next few decades, there will be further warming and sea-level rise for centuries to come. This will result in adverse impacts on human health, natural ecosystems, and the economy. Co-ordinated action is needed urgently to put the world on a different emissions trajectory (figure 1).
Quantifying the Value of a Future Pressure Transient Well Test with Reservoir and Measurement Uncertainty
Authors: Prange Michael , Bailey William John , Kuchuk Fikri J. 
Published: May 2016

Abstract
We present a consistent and functional methodology for conducting value-of-information (VoI) analysis on proposed well tests in the presence of multiple critical uncertainties associated with the reservoir and the measurement/interpretation. Such uncertainties can impact asset economics acutely when they influence recoverable hydrocarbons. A key feature of this analysis is that the value of the measurement is determined before the measurement is made. Our demonstration uses an example of a marginal offshore asset where severe compartmentalization is possible. In this example, the VoI is a critical deciding factor because it is not obvious a priori that this value will justify the cost of the test in this marginal asset.
Our analysis uses a novel approach to standard decision trees by introducing new decision tree nodes in the form of "uncertainty" and "transformation uncertainty" nodes that can accommodate single or numerous continuous and discrete uncertainties. Without such novel tree components, a standard decision tree would become far too cumbersome for practical purposes and may even result in sub-optimal (uneconomic) development decisions from being made because of the discretized nature of the existing decision tree constructs.
We also consider, in addition to the reservoir uncertainties, the uncertainty in the well test measurement and/or the interpretation itself. We present expected asset net present value as a function of measurement uncertainty. Since well-test uncertainty can be related to the well-test duration, we show how the optimum well-test duration can be determined by identifying the time at which the difference between VoI and test cost is maximized. The cost of running the test longer than this optimal duration will only serve to reduce the net present value of the asset.

Introduction
The problem of establishing meaningful value-of-information (VoI) metrics for a well test when faced with multiple significant uncertainties is examined. Such uncertainties can impact asset economics acutely when they influence recoverable hydrocarbons. We examine this VoI through an example of a small, marginal, offshore asset where the primary reservoir uncertainties relate to the degree of possible compartmentalization as well as permeability and porosity. The underlying driver of this study was to devise and test a consistent and functional methodology that can compute meaningful VoI for a well test such that all significant uncertainties are considered, including measurement uncertainty.
Dukhan 3D: An Ultra High Density, Full Wide Azimuth Seismic Survey for the Future
Authors: Seeni Salva R. , Robinson Scott , Denis Michel , Sauzedde Patrick 
Published: May 2016

Abstract
This paper presents a case study on the logistics and acquisition of a large, ultra high density and full wide azimuth 3D seismic survey across the Dukhan field for Qatar Petroleum (QP), Figure 1. This survey represents a step change in seismic data acquisition providing greatly enhanced data quality by full wide azimuth and very dense spatial sampling complemented by good quality uphole and simultaneous 3D Vertical Seismic Profile (VSP) recording. It is expected that this survey will set an industry standard for seismic acquisition leading to improved field redevelopment. While the 3D seismic data can always be re-processed in the future, it is possible that future re-acquisition of the entire Dukhan field area may be difficult or impossible to justify. Therefore one of the key driving principles behind the survey design was to ensure that QP did not under specify the source and receiver effort so that it represented a "no regrets" case for the future.
There are several key operational elements to this survey, the complexity of terrain which varies from sand, rock and sabkha to marine transition, busy infrastructure both residential and industrial i.e. townships, QP's oilfield installations and thirdparty quarries and factories. All of these operational elements must be managed successfully to achieve QP's technical objectives for high quality seismic data.

Introduction
The Dukhan field is a major oil field in Qatar discovered in 1939; it contains more than 350 wells producing from 4 major reservoirs. It has a complex history of production & development strategies, starting with natural pressure depletion for more than 20 years, followed by power water injection since 1989 and gas cap cycling since 1998. As with other large mature Middle East oil fields, Dukhan has also witnessed significant changes in technology over the last 60 years. In order to maximize the long term economic recovery from the field, QP is committed to applying leading edge but fit-for-purpose technologies. New, state of the art, 3D seismic data providing updated reservoir models will enable QP to continue the development of Dukhan field for many years to come.
Hydrydrocarbon Generetion & Natural Gas Accumulation In The Southern Margin Of Junggar Basin
Authors: Yang Haibo , Changyong Zhao , Yanping Qi 
Published: May 2016

Abstract
1. In the southern margin area, four sets of source rocks including Permian, Jurassic, Cretaceous and Tertiary source rocks are developed, and their distributions and maturities are very different.
In the southern margin of Junggar Basin(mainly in the western section of the southern edge), four sets of source rocks including Permian, Jurassic, Cretaceous and Tertiary source rocks are developed. Permian and Jurassic source rocks are basically located at the southern edge of the region; Cretaceous source rocks are mainly located in the Huo- Tu - Ma region; Tertiary source rocks are mainly located in the vicinity of Sikeshu area.
The four sets of source rocks at the southern edge of the region have hydrocarbon potential. The abundance of organic matter in Permian and Lower Jurassic source rocks is higher, and the organic matter types are mainly type ?, the abundance of organic matter in Cretaceous and Tertiary source rocks is slightly lower but the organic types are better which are dominated by type?and type?. Permian source rocks are at the mature-high mature stage in this region; Jurassic source rocks are in a low-mature-high mature stage; Cretaceous source rocks is in immature- mature stage, but the Cretaceous source rocks in Wusu-Changji area are in the peak of oil generation; Tertiary source rocks of most region is in immature-low mature stage, but the source rocks reached a mature stage in the Sikeshu depression.
Elastic time-reverse modeling imaging conditions
Authors: Artman Brad 
Published: May 2016

Abstract
Since the Earth is elastic, it is worth the computational burden to process multicomponent data for elastic phenomena with fully coupled time-domain wave-equation propagators. At every time sample in the back-propagated model domain, the complete wave field is decomposed exactly into compressional and shear wave components by simple spatial derivatives. Then, physically significant images are extracted from extrapolated hyper-cubes by applying appropriate imaging conditions. To locate subsurface sources (or diffractors) with the time-reverse modeling algorithm, the imaging condition required is the correlation of P and S energy since only at the source location are the two events collocated. The impulse response of the algorithm is anti-symmetric in physical space and can be enhanced through post-processing with a spatial derivative or integral.

Source Focusing
The time-reverse modeling (TRM) algorithm was developed for locating sources within a model domain (Fink, 1999; Gajewski and Tessmer, 2005). The method is suited for locating earthquakes, microseismic events, or tremor sources. The difference between TRM and reverse-time migration (RTM) (Levin, 1984) is the lack of a known source wave field for TRM. Otherwise, data are treated in the same manner: reversed in time and used as source functions at the acquisition locations.
The difference between a specular reflection and a stimulated heterogeneity, or diffractor, is that data contain only a direct arrival ray path: The "from-path". This contrasts to reflection seismic whose time delays are the sum of the "to-path" and the "from-path." Without some knowledge of the to-path, imaging algorithms based on delays between a reference event and a scattering event, including RTM and interferometry, are incapable of finding sources within a domain. In contrast, the TRM algorithm exploits the ability to collapse travel-time surfaces (hyperbolic cones) using wave-equation propagators.
Laboratory Studies At Reservoir Conditions On The Impact Of Acid Gas And CO2 Displacements On A Carbonate Matrix
Authors: Obeida Tawfiq A. , Kalam Mohammed Zubair , Al-Sahn Hani , Gibson Adrian P. , Masalmeh Shehadeh K. , Zhang Hongmei 
Published: May 2016

ABSTRACT
Laboratory studies have been performed to evaluate the impact of acid gas (80% H2S, 20% CO2) and CO2 injection on the carbonate matrix properties at reservoir conditions. Injectivity abnormalities have been reported in the literature in several WAG projects involving CO2 and loss of injectivity has been crucial factor in many of these projects. However, literature data shows that some reservoirs loose injectivity and others increase injectivity after the first CO2 slug is injected. Change in rock properties due to fluid/rock interaction can account for some of the injectivity loss.
In this paper we will report on recent laboratory study that was conducted using limestone and dolomite reservoir core samples from a carbonate reservoir in Abu Dhabi. The laboratory program used core plugs, or plug composites, that had been aged with reservoir oil at a representative initial water saturation prior to the gas displacement. The displacements were performed with three fluids:Vapor phase CO2Acid gas (80% H2S, 20% CO2)Brine saturated with CO2
The vapor phase CO2 and acid gas displacements were considered to be typical of those found near a gas injector, whereas the brine saturated with CO2 displacement was more representative of the reservoir away from the well bore or found during a WAG process. The displacements were conducted at a series of increasing rates. After 75 pore volumes the plug was left to soak for 48 hours in the displacing fluid. Two further displacements were then performed. Following the displacement tests, an assessment of damage to the core plug was made by measuring the porosity, permeability, SEM, XRD, MICP and taking thin sections of the core plug. This paper also presents laboratory work to study CO2 solubility in different brine salinities up to 250 K ppm at different reservoir temperatures up to 149 C and pressures up to 400 bar. A CO2 solubility model is proposed to calculate solubilities at representative salinity and previlent pressures and temperatures.
The preliminary results show that in most of the experiments no significant change in permeability was observed. However, in some experiments both enhancement and decrease in permeability was reported. The results of this ongoing study will strongly impact the planning of EOR development options. Injection of CO2 or acid gas will be significantly hampered if the gas injection results in matrix plugging or core damage, and needs to be appropriately evaluated for the reservoir under consideration.
Multi-Component Seismic Applications for Maximizing Efficiency and Production
Authors: Maili Eduard , Negulescu Carmen 
Published: May 2016

Summary
Carbonate reservoirs are often very heterogeneous and their properties are frequently difficult to understand. The presence of faults and intense natural fractures further increases the complexity that becomes very challenging for reservoir management and field development. This is the case of the Shuaiba reservoir in Idd El Shargi North Dome (ISND) Field in offshore Qatar. The field was discovered in 1960 and was first produced in 1964. The oil is produced from multiple reservoirs, primarily carbonate, on a salt induced faulted anticline. After 1995, when Occidental Petroleum assumed the operatorship role under a Production Sharing Agreement with the State of Qatar, an extensive horizontal well drilling and waterflood campaign resulted in a substantial production increase from the primary Arab and Shuaiba reservoirs. This paper will focus on the Shuaiba development results. New technologies have been applied to effectively manage the Shuaiba waterflood and continuously increase the oil recovery factor in this complex reservoir.
The practical aspects of multi-component seismic technology described in this paper can be applied in any complex fractured reservoir for improving efficiency and increasing recovery.
During 2003–2005, Qatar Petroleum and Oxy acquired and processed a large 4C3D seismic survey over Idd El Shargi field (Fig.1). This technology uses multi-component phones and cross-spread acquisition geometry to record both compressional and shear (converted) waves. The survey ensured full azimuth coverage to offsets up to 3000 m, equivalent to an offset/depth ratio of two for the main target zone, achieving a nominal fold of 240 in the natural bin size, or a trace density of more than 2.7 million traces per square kilometer. The data were processed through a flow that carefully preserved the azimuthal anisotropy (Angerer et al, 2006).
Preventing and controlling endemic diseases in a pipeline construction in Amazon region
Authors: Chimelli Mauricio Abi Ramia , Alves Lima Gilson Brito 
Published: May 2016

Abstract
Preventing and Controlling Endemic Diseases in Amazon Region were identified as the most important action of the work environment. This project was implemented during the URUCU-COARI-MANAUS pipeline construction as a model project to be improved in Health, Safety and Environmental (HSE) practices. After discussions with management and other stakeholders, several teams of prevention agents were trained for the project's development. Actions were taken to import HSE knowledge and training to all on site personnel indicated by contractors. The main focus of the actions was on worker's immunization and workplaces fumigation necessary for the project improvement. The validation of the training and implementation of actions was closely monitored by the Health, Safety and Environmental (HSE) Petrobras teams and by the stakeholders. There were 9.000 workers in the middle of Amazon forest during the construction and no endemic diseases infected them. There were 499 confirmed cases of Malaria in workers; however, all of these workers were contaminated before workplaces entrances, ratifying the project's control success. The implementation of this project resulted in one hundred percent (100%) of workers immunized for Yellow Fever, Tetanus, and Hepatitis A and B. During construction, the incidence of Malaria in surrounding communities decreased around thirty percent (30%). Project benefits' include lower accidents rates, because the Brazilian legislation considers as accident, the appearance of endemic diseases in workers, and several new water treatment in surrounding communities in order to prevent water transmissible diseases which are very common in Amazon Region. This project resulted in trained of experts among local, which are now capable of preventing and controlling endemic diseases.
Pearl GTL Village - Setting New Standards
Authors: Fabricius Niels , Hodder Lee , Ring Ben 
Published: May 2016

Abstract
The Pearl GTL Project is a fully integrated upstream/downstream project producing 140,000 bbls per day of GTL products and 120,000 boe per day ethane, LPG and condensate. It is located in the Ras Laffan Industrial City (RLIC), some 80 km north of Doha in Qatar.
Much has been written and presented on the large dimensions and complexity of this world scale project, amongst others highlighting the fact that over 48,000 workers are involved during the peak of its construction activities. This paper will describe the infrastructure facilities and support functions that have been established to accommodate a large number of workers in RLIC.
Recognising that many workers will be involved in the project for several years, there has been a conscious move away from the idea of simply a 'camp', and the facility's name, 'Pearl GTL Village', reflects the aim to be more of a community. So, workers - who have come to Qatar from more than 60 countries to build the GTL plant - do not just sleep there: they live in the Pearl GTL Village, which has been developed into a fully-fledged community that makes the workers feel at home. The differentiators include:• The 'Al Muntazah' recreational area, in the heart of the Pearl GTL Village, includes sports fields (cricket, football, basketball, softball and tennis), an outdoor movie theatre, food stalls, shops, Internet cafes, places of worship and shaded seating areas.• Across the Village, there is a workforce of over 1,800 to keep everything up and running, including almost 500 cleaners and over 1,000 kitchen staff. In addition, there are medical facilities, and there is a welfare team including qualified counsellors.• An overall management team, led by a Village Mayor in place to ensure that consistent operational and welfare standards are applied across Pearl GTL Village.
The entire village is supported by infrastructure facilities that include a sewage system, combined potable water and fire water system, power distribution throughout the camp supplied initially by 84 diesel generators and later by a 33kv direct feed from a new Kahramaa substation, a telecommunications network for both voice and data for the entire camp, common recreational facilities, a waste water treatment plant equivalent to that needed for a small town to process sewage from the camp, roads and fencing.