bluuebunny/crossref_metadata_2025_split huggingface dataset:
Uncertainty Mitigation Using Data Acquisition in Volcanic Reservoirs
Authors: Gupta A. K. , Sabharwal V. , Kumar R. , Mund B. , Beohar A. , Saurav S. , Shankar P. , Tiwari S. 
Published: April 2017

Abstract
The Raageshwari Deep Gas Field (RDG), Barmer Basin, India, is a thick (~900m gross), low permeability (0.01-1md) gas condensate field (CGR: ~70 STB/MMscf). The pay-zone consists of a poorly sorted sandstone interval on top of stacked succession of volcanic lava flow cycles. The field is being developed through multi-stage hydraulic fracture stimulations to allow production at economical rates. Recently two hydraulic fracturing campaigns comprising of 125 stages in 20 wells were successfully completed which have resulted in significant improvement in well productivity. This paper highlights the integrated workflow applied in a volcanic reservoir to reduce subsurface uncertainty and value addition in optimizing hydraulic fracturing operation.
To account for the complexity associated with volcanic rocks, a fit for purpose integrated petrophysical and geomechanical workflow was developed using a basic wireline logs, processed NMR, dipole sonic and image log analysis. The model was calibrated with dynamic data especially diagnostic fracture injection test (DFIT), pressure build up and production logging tool (PLT) analysis. The final calibrated model was used to identify the net reservoir packets along the well length, which further helped to identify the optimum locations to create hydraulic fractures. A typical log motif generated using the integrated model is given in Figure-1.
As seen on the generic log in Figure-1, net reservoir intervals are in multiple packets of varying thickness contained throughout the thick gross reservoir package. Connecting maximum net reservoir packets through hydraulic fractures is critical for maximizing the well productivity and EUR. The limited entry fracturing technique (Lagrone and Rasmussen, 1963) was used to connect the maximum net reservoir with a fewer number of stages and a lower cost. Extensive data acquisition (extended DFIT, formation wise testing, PVT sampling, PLT and pressure build-up) was carried out to increase reservoir understanding followed by detailed subsurface modeling.
The extensive data acquisition programme was successful in reducing a number of uncertainties, including: reservoir information, effective fracture parameters and presence of natural fractures. The key outcomes from the two frac/data acquisition campaigns are as follows: The integrated petrophysical and geomechanical model enabled us to improve the net connected reservoir by 65% in the volcanic sectionsThe optimisation of the number of frac stages and their costAn improved subsurface understanding in well deliverability, frac conductivity, half-length and frac heightConfirmation of gas contribution from each perforation and the establishment of deeper gas which validated petrophysical payA new, more accurate, poro-perm transform calibrated with permeability estimation using DFIT and pressure build upA better subsurface understanding which supports higher estimates of GIIP and EUR
Effect of Reservoir Heterogeneities and Model Uncertainties on Prediction Versus Actual Field Behavior- A Case Study
Authors: Kumar Rajesh , Shankar Vivek , Batra Surseh K. , Kumar Atul 
Published: April 2017

Abstract
A case study on the effect of reservoir heterogeneities and reservoir model uncertainties on prediction versus actual field behavior and efforts being taken to improve oil recovery in Bhagyam field is presented in this paper.
Bhagyam field is the second largest onshore oil field in RJ-ON-90/1 block, Rajasthan India. The main reservoir has large variations in rock and fluid characteristics. The reservoir porosity range between 20% to 30%, and the maximum in-situ permeability ranges up to 30 Darcies, although the average permeability is 3 Darcy. The in-situ viscosity of crude oil ranges between 20 and 400 cP. The commercial production from the field started in 2012 at an initial rate of 15,000 bopd; the field attained production of ~25,000 bopd, although the envisaged production was 40,000 bopd as per the Field Development Plan (FDP). Based on the drilling and production performance of wells, a significant gap between actual and reservoir model based predictions was observed due to various reservoir uncertainties and complexities. Some of the key factors impacting the overall performance include lower effective permeability, higher oil viscosity, lower transmissibility, and wellbore issues.
Based on the large gap observed between predicted and actual field data, it was estimated that a much denser well spacing was required to achieve recovery estimated in the Field Development Plan. Coupled with a very unfavorable mobility ratio (due to the high in-situ oil viscosity), the water breakthrough was more rapid and widespread early in the production life of the field. Therefore, it was not possible to achieve the peak production rate and recovery in the FDP, even with the drilling of additional wells. The oil production has continued to decline with increase in water cut.
The field is currently producing around 14,000 BOPD with 88% water cut. The reservoir pressure is being maintained through current average water injection of more than 100,000 barrels per day. As of the time of writing, approximately 7% of the initial oil in place has been produced from the field. In order to maximize incremental oil recoveries over waterflood recoveries through improvement in sweep efficiency, various reservoir studies have been carried out to evaluate the feasibility and benefits of implementing a suitable chemical EOR technique in the field.
The case study is a useful reminder of how heterogeneity and reservoir complexity can affect field development plans and how active reservoir management and production optimization can add significant value to field understanding and value.
Data Integration Helps in Identifying New Waterflood Opportunities in Western Desert, Onshore Field
Authors: Choudhary Manish , Nair Saritha , Pal Sabysachi , Munimandha Amuktha , Kohli Abhinandan , Nirmohi Samiksha , Gupta Shyam , Jain Sid 
Published: April 2017

Abstract
Integrated analysis of data together with fit-for-purpose modelling can help in fast track maturation of opportunities. In 2012, an opportunity to increase oil by implementing waterflood was identified, and last year was further reviewed by Shell. An integrated approach helped the team to mature ten development wells within three months which were subsequently drilled and helped the operator to surpass their production targets.
The field located in Western Desert, Egypt comprises of an Upper Cretaceous tidal channel system across four key reservoirs where sand thickness ranges between 2-15 m. Large uncertainties in reservoir extent, architecture and properties required the integration of data across multiple disciplines for identifying new development wells.
It was recognized early on that the construction of full-field fine-scale static models would be time-consuming and hence a simplified fast-track approach was used for maturing the opportunity. Conceptual depositional models were built by integrating dipmeter data, image logs and core facies descriptions to understand the direction of continuity of tidal channels, tidal bars and mud flats.
Net sand thickness maps were then constructed to represent the conceptual depositional model and integrated with the production behaviour of the wells. Production from historical wells drilled up to 2012 caused non-uniform pressure depletion across reservoirs. The pressure data from Modular Dynamic Tester (MDT), along with the production-injection history, was reviewed to identity both areal and vertical stratigraphically connected areas which were incorporated in the net sand maps. The constructed maps were quality checked with pressure and production data so as to validate the range of in-place volumes. Net sand maps, porosity maps and saturation models were combined to generate Hydrocarbon Pore Volume (HCPV) maps used to identify new well opportunities.
Separate sector models were also constructed to evaluate the waterflood and to optimise the decision parameters like injector-producer spacing, injection rates, voidage replacement ratio and target reservoir pressure. A range of type curves were generated from Monte Carlo simulation runs for all key sub-surface uncertainties then was used to estimate the low, base and high case recoverable volumes for the identified well locations and patterns.
The identified wells were drilled between February and August 2015 and helped increase production rates of the field by over 5,000 stb/d.A fit-for-purpose modelling using sand maps and connectivity maps can often greatly help in fast-tracking opportunity maturation and fine-scale detailed simulation modelling may not provide additional value.
A Practical Solution to Overcome Challenges in Unconventional Reservoir Simulation and History Matching Using Integrated Petrophysical and Facies Modeling Approach
Authors: Saikia Kalyan , Baruah Chinmay 
Published: April 2017

Abstract
In an unconventional reservoir, a thorough understanding of the spatial distribution of the physical properties of rocks, in terms of facies, porosity, and permeability, is essential for realistic dynamic reservoir simulation and history matching. This paper provides a practical solution for enhanced reservoir performance analysis, combining the results of geological interpretation, 3D geostatistical electrofacies modeling, and flow simulation in an unconventional Eagle Ford shale play. The first step of the integrated approach is the application of hierarchical clustering methods to identify electrofacies groups using log curves. Next, electrofacies are converted into lithofacies through an analysis of core data. The 3D lithofacies and petrophysical distribution model is then created using stochastic geostatistical techniques. In the reservoir simulation step, the discretized facies model is constrained to assign geomechanical properties. Thus, a realistic fracture model is generated with a proper definition of fracture characteristics to control flow simulation and to enable better history matching. The solution presented in this paper provides an objective means of using the integrated approach in an accurate definition of fracture properties, in terms of length and orientation, for reservoir simulation and production forecasting in unconventional reservoirs.
Sidetracking of Peripheral Injector for Tapping Bypassed Oil: Case Study from a Matured Carbonate Reservoir of Mumbai High Field
Authors: Ray Suhrita , Bagchi Prodip , Medhekar S. D. 
Published: April 2017

Abstract
In the 3rd Phase of redevelopment scheme of the northern part of the Mumbai High Field the focus has been on exclusive development of "U1" i.e. the topmost layer of L-III reservoir, mainly in the western flank area through drilling new wells and side-tracks.
Among the multi-layered accumulation of L-III reservoir, U1 is the most prolific layer with good hydrocarbon facies development in the western flank and holding the highest hydrocarbon in place of L-III. U1 layer is well established in areal extent along the western part of MHN structure bounded by GOC in the east and OWC in the west. Presence of large scale bypassed oil in U1 layer in the western flanks have been appraised through production of infill wells drilled under U1 additional development scheme in the past.
Review of water injection for U1 layer was carried out based on water cut trends and flood front movement in the reservoir. With the help of dynamic production data and saturation maps as generated from simulation model, bypassed oil opportunities were obtained in U1 layer in the western flank. Formation evaluation study based on electro-log records in the nearby wells also showed significant oil saturations in U1 layer. Based on these detailed studies, injector well ‘WI-X’ from WI platform (located in the western periphery of the field) was identified as a candidate for side-track as a horizontal producer in U1 layer. Further, analyzing nearby wells' production vis-à-vis injection scenario the location was optimized and decided to side-track keeping a distance of around 800-900 m away from the flooded area of the injector well ‘WI-X’. This would ensure in avoiding early breakthrough of injection water and optimize the well location in the relatively un-drained area. After side-tracking and initial testing, the well came up with 600 bopd with 70% of water cut. This well has also been completed with intelligent completion with a view to manage water cut in the well owing to its proximity to water injection platform.
The present study highlights the importance of identifying bypassed oil opportunities contained in thin oil layers like U1. It also signifies the importance of application of integrated methodology viz. dynamic production data, simulation model results and well logs analysis to enable a definitive identification of such locations.
A Workflow to Model Performance of Low Permeability Reservoirs for Devising Most Optimal Development Strategy Using Rate Transient Analysis and Single Well Modeling
Authors: Sharma Shivam , Batshas Siddhanta , Joshi Sameer , Reddy Vinil , Chhabra Sameer , Sastry Bharath , Subrahmanyam P 
Published: April 2017

Abstract
Modern advancements in technologies pertaining to the drilling of horizontal well and multi stage hydraulic fracturing have made it possible to get significant hydrocarbon production even from extreme low permeability formations. However, correct evaluation of the economics of the project is becoming increasingly essential before committing to any big investment. In this scenario, production forecasting based on reservoir simulation plays an important role by not only evaluating the economic feasibility of the project, but also helping in the selection of the most optimal development strategy. In this paper, a workflow has been demonstrated that proved useful in addressing such challenges related to the tight reservoirs (permeability less than ~2mD).
The methodology adopted in this study can be divided into two parts. The first part involves data preparation for single well numerical modeling similar to Daungkaew et al (2008) and Kumar et al (2008). This includes building a petrophysical model based on the mineralogy characterization and also carrying out Rate Transient Analysis (RTA) for permeability estimation using the data acquired from an existing well (Pan et al, 2011). RTA is preferred over the conventional buildup analysis as it does not require shutting of the well. The second part of the workflow involves creation of a numerical model based on the petrophysical, PVT and SCAL data. Hydraulic fracture (if present) is modeled by editing the permeability of the grid cells falling under the fracture geometry. The model is calibrated with the production data after initializing with the pressure and fluid contacts. The history matched model is then used to generate production forecasts of multiple scenarios including horizontal well with multiple stages of fracturing and sensitivities can be made with respect to drainhole length, fracture stages etc. Furthermore, economic analysis can be carried out to select the most economically viable case.
The proposed workflow has been applied in one of the low permeability oil field in India. The permeability derived from RTA was in close agreement with the core results. This workflow was used to generate production forecasts for multiple development scenarios. It was used to optimize the number of fracture stages, keeping the drainhole length constant.
In this paper, a novel approach is discussed that combines the RTA and single well numerical modeling technique to evaluate different strategies of producing from a tight reservoir. Based on the economic analysis then, one can maximize the return.
Getting Past the Deepest Barrier Using Plasma Based Punctures: A Case Study on the Mature Panna Field, Western Offshore, India
Authors: Abbasi Shariq , Tyagi Chirag , Chakrabarty Toushar 
Published: April 2017

Abstract
Panna field is located in the western offshore region of India and produces oil and gas from Middle Eocene and Early Oligocene Bassein limestone. Production is taken mostly through 3 ½" or 4 ½" tubing through a packer set in 7″ liner. The Panna-Mukta-Tapti Joint Venture (PMT JV) took up a plan to revive wells addressing well integrity issues and limitations associated with old completion jewelry for increasing the production.
Work-over campaign was planned for four wells on PB and three wells on PC platform to enhance production. The plan was to cut and retrieve the old completion and tubing above the 7″ permanent packer and install improved completion, having facilities of Permanent Down Hole Gauges (PDHG), Gas Lift Mandrel (GLM) and Chemical Injection Mandrel (CIM) through an additional packer set in 9-5/8″ casing.
In line with two barrier philosophy, two plugs were set inside the production tubing, one at TRSSV (shallow-set) and another one below the production packer (deep-set). The plug below the production packer doubled-up to also hold back the workover fluid, which may have hampered the productivity of an already sub-hydrostatic reservoir, if losses occurred. However, at the end of workover operations, the retrieval of this deep set plug could not be done even after various attempts and spending valuable rig time. This problem was faced with three out of the first four wells, which proved to be a challenge and forced the team to devise a new strategy for remaining wells.
At this point, an ingenious solution was devised to employ Plasma Based Punctures (PBP) to puncture the tubing in the limited space between the packer and the deep set plug to kick back the wells into production. Rig based PBP operations were carried out on two PC wells and Rig less PBP operations were carried out on three PB wells to get them online post work over operation. This resulted in saving several hours of rig time as the deep set plugs could not be retrieved in the conventional planned slick line operations.
This paper intends to highlight the challenges faced, and how PBP proved to be the optimum solution, by simplifying operations and ensuring the timely delivery of production.
The PBP operations proved viable through savings on energy, resources, time and cost associated with work-over jobs. The potential savings were roughly 780,000 bbls of oil which were significant for the aging asset. It is therefore, a potent alternative to other costly solutions in a scenario that often fails to deliver objectives, as happened in this campaign.
Fluid Type Identification in Carbonate Reservoir Using Advanced Statistical Analysis
Authors: Yu Hongyan , Wang Zhenliang , Rezaee Reza , Liu Xi , Zhang Yihuai , Imokhe Omolegho 
Published: April 2017

Abstract
Fluid type identification in the carbonate reservoirs is always a challenge work due to the heterogeneous composition. The normal resistivity well logging data cannot separate gas and water formation for such complex reservoirs has been reported in the former studies. Moreover, the traditional cross-plot also cannot find the low limit value. Thus in this paper, we proposed the new statistics evaluation methods to solve such problems based on multi-parameters identified method which chose 10 parameters as dataset and utilized decision tree to build the rules, and discriminant analysis which build 2 predictive models (A and B) to classify the gas and water. We indeed successfully applied our new methods on the true well logging data from a heterogeneous carbonate reservoir in China. Thus we concluded that our new methods could be a good way in the future well logging evaluation for complex carbonate reservoir.
Spatial Analysis of Horizontal-Shale-Well Water Production in the Wattenberg Field
Authors: Bai Bing , Carlson Ken 
Published: April 2017

Summary
Reusing waste water from the oil field for hydraulic fracturing has become an important topic in the oil and gas industry, and it requires a thorough understanding of both the quality and quantity of the waste water. In this paper, water production from horizontal shale wells in five sections of the Wattenberg field in northeastern Colorado was analyzed. Models were developed for these wells for future water-production prediction. A spatial analysis was also conducted by comparing water production from each section with the gas/oil-ratio (GOR) value for each well. Results indicate that the GOR value of wells has a significant impact on water production in the first year of operation. Wells with low GOR value tend to have higher fracturing-flowback volume and, furthermore, water-recovery rate. Results from this study also provide valuable information for estimating water production from unconventional shale fields, which is critical for the design of wastewater collection and treatment facilities in the field.
FAMÍLIA, DIGNIDADE DA PESSOA HUMANA E RELATIVISMO CULTURAL
Authors: Padilha Elisângela , Bertoncini Carla 
Published: April 2017

<p>o presente artigo tem por objetivo investigar sobre o que define a família no mundo contemporâneo sob o ponto de vista cultural. Seria possível, com fundamento na dignidade da pessoa humana, estabelecer um conceito multicultural de família? À família sempre coube um papel essencial na vida do homem, representando o modo pelo qual este se relaciona com o meio em que vive, priorizando a plena realização pessoal de cada membro familiar, com base no afeto, na busca pela felicidade, no respeito à dignidade da pessoa humana e seus direitos fundamentais. Família e sociedade conjugam-se em uma relação sistêmica. A família deve ser entendida como a comunidade de vida material e afetiva de seus integrantes, união de esforços para o desenvolvimento de atividades materiais e sociais, convivência que promove mútua companhia, apoio moral e psicológico, na busca do melhor desenvolvimento da personalidade das pessoas que a compõem. A família não é um produto da natureza e estática no tempo, e sim um grupo dinâmico que reage e interfere na sociedade. Nesse contexto, é possível, com fundamento na dignidade da pessoa humana, buscar um conceito de família que possa ser pensado e entendido em qualquer tempo e espaço.</p>
Is Stem Cell a Curer or an Obstruction?
Authors: Damayanti Siska , Triana Rina , Chouw Angliana , Dewi Nurrani Mustika 
Published: April 2017

Introduction: Each cell in human body is assigned with a specialized function to perform. Before a cell becomes specialized, it is a stem cell. Stem cell research and therapy is progressing dramatically these days. Stem cell therapy holds enormous treatment potential for many diseases which currently have no or limited therapeutic options. Unfortunately, this potential also comes with side-effects. In this review, the positive and negative effects of regulation of stem cells will be explained.Content: Stem cells are undifferentiated cells that have potential to develop into many different cell types in the body during early life and growth. The type of stem cells are embryonic stem cells, induced pluripotent stem cells, somatic stem cells, foetal stem cells and mesenchymal stem cells. Stem cell transplantation is one form of stem cell therapy, it comes with different sources, and those are autologous and allogenic transplantation stem cells. In an autologous transplant, a patient’s own blood-forming stem cells are collected, meanwhile in an allogeneic transplant, a person’s stem cells are replaced with new stem cells obtained from a donor or from donated umbilical cord blood.Summary: Its abilities to maintain undifferentiated phenotype, self-renewing and differentiate itself into specialized cells, give rise to stem cell as a new innovation for the treatment of various diseases. In the clinical setting, stem cells are being explored in various conditions, such as in tissue repair and regeneration and autoimmune diseases therapy. But along with its benefit, stem cell therapy also holds some harm. It is known that the treatment using stem cell for curing and rehabilitation has the risk in tumor formation.