bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Successful Selection, Optimization and Implementation of Adjust While Drilling AWD Flowchart in Offshore Oil Field of Bohai Bay, China
Authors: He Yifan , Hu Yong , Shi Hongfu , Zhou Junliang , Shu Xiao 
Published: April 2019

Abstract
BZ field is located at Bohai Bay of China, it is featured with multiple complex fluvial reservoirs with small lateral extension (100-300m wide) and thin accumulation (6-12m). Many channels are isolated and poorly connected across the field. As a result of the fluvial narrowness, low reserve abundance and limited natural energy, the development of this field was tied back into the neighboring field facilities and was categorized as the marginal value field with low ROR (rate of return). This paper presents a successful implementation of the flowchart of "adjust while drilling" to tap these kinds of reservoirs during the E&P circles.
In the ODP design phase, 13 well slots were reserved for the future use. And the overall geological characteristics is predicted to be much complex.
In order to mitigate risks, identify potential opportunities and improve the benefit of plan, a work flow integrating seismic, geology, logging and productivity forecast, with exploration concepts was designed during development phase to optimize drilling schemes.
The process is divided into 5 steps: 1. Locate and characterize key sands by combined analysis of logging and seismic data. 2. Recognize hydrocarbon migration pattern, identify potential oil-bearing sands, and estimate OOIP; 3. Design well patterns and forecast productivity based on the reservoir characteristics and OOIP. 4. Optimize drilling sequence and well trajectory; evaluate reservoir potential and risks based on data from drilled wells, and then optimize future well locations. 5. Apply logging while during drilling (LWD) and Periscope to reach optimal landing point and ensure high NTG.
Modifications to the ODP mainly include: 1. Staggered line well pattern was adopted to develop single story channel. 2. A large number of horizontal wells were adopted. 3. Understanding on the relationship between production wells and injection wells were improved by placing the deviated injection wells at the multi-stored channel stacking. And the well spacing was determined based on the updated reservoir properties to warrant waterflood sweeping conformance and efficiency. 4. Newly proved potentials were targeted through remaining reserved slots.
Through this process, OOIP has increased by 108%, production well counting has risen from 19 to 32, locations of 9 wells reserved during ODP phase have been successfully optimized and redirected; independent P-I pairs have been positioned for each single story channel with the P-I ratio over 90% and good response between those pairs. Average productivity has reached 1.5 times of the designed level.
The overall successful development of BZ field has proved the effectiveness of the flowchart, which is designed for the risk mitigation, potential tapping, slot utilization and financial performance enhancement. Therefore, it provides an insightful guidance for the future similar reservoirs development program design.
Effective Igneous Reservoir Identification and Controlling Factor Analysis in Eastern Sag of Liaohe Depression, China
Authors: Hu Zhenhua , Zhang Shenqin , Wu Fangfang , Liu Xunqi , Wu Jinlong , Li Shenzhuan , Wang Yuxi , Zhao Xianran , Zhao Haipeng 
Published: April 2019

Abstract
The igneous reservoir of Shahejie formation in eastern sag of Liaohe depression is characterized by complex geological environment, variable lithology and high heterogeneity. Reservoir evaluation is difficult only based on conventional logs due to complex lithology and pore structures. Effective igneous reservoirs were identified and reservoir controlling factors were analyzed based on effective porosity calculation, pore structure analysis, lithology identification, lithofacies analysis, fracture evaluation and heterogeneity analysis by combing nuclear magnetic resonance data, micro-resistivity image data, conventional logs as well as mud logging data.
Based on our study, the igneous reservoirs in the study area are more related with effective porosity and pore connectivity, and less related with fractures. Good reservoirs are mainly distributed on the top part of explosive facies and effusive facies, where lithologies are mainly Trachyte, volcanic breccia and breccia-bearing tuff. The weathering leaching process is quite important for igneous reservoirs, but the reservoir qulity would not be good if the weathering process is too strong as it will lead to low effective porosity.
The accuracy of igneous reservoir evaluation gets improved a lot by this integrated approach and the conclusion from this study will help to optimize igneous reservoire exploration plan.
Fracture Network Mapping Using Integrated Micro-Seismic Events Inverse with Rate-Transient Analysis
Authors: Wang Wendong , Zhang Kaijie , Su Yuliang , Tang Meirong , Zhang Qi , Sheng Guanglong 
Published: April 2019

Abstract
In the development of shale oil and gas reservoir, hydraulic fracture treatments may induce complex network configuration, which is very challenging to characterize. The existing fracture properties interpretation methods mostly rely on simplifying assumptions and are typically empirical in nature. The aim of this work is therefore to introduce an integrated framework involving fractal theory, inverse analysis of micro-seismic events (MSE), and rate-transient analysis to map the heterogeneity and distribution of fracture properties. In this work, a general framework is proposed to characterize both the geometry configuration and the owing properties of the complex fracture network (CFN). The CFN characterization framework is naturally divided into two stages: characterize the fracture geometry network by microseismic data and characterize the fracture dynamic properties by production data. In the fracture configuration characterization stage, a stochastic fractal fracture model based on an L-system fractal geometry is applied to describe the CFN geometry. Moreover, the genetic algorithm (GA) as a mixed integer programming (MIP) algorithm are applied to find the most probable fracture configuration based on the microseismic data. As to the owing properties characterization stage, we introduced embedded discrete fracture model (EDFM) for the computational concern and a Bayesian framework is used to quantify these fracture dynamical properties e.g., conductivity, porosity and pressure dependent multiplier by assimilating the production data. In addition, rate-transient analysis is also applied to calibrate the total fracture length and estimate effective stimulated-reservoir volume (ESRV). In order to validate this framework, a synthetic numerical case is developed. The result indicates that our integrated framework is able to characterize both CFN configuration and properties by assimilating microseismic and production data sequentially. The proposed workflow shows that the characterized CFN model would yield reasonable probability predictions in unconventional production rate.
An Assessment of the Impact of Rheological Properties on Rate of Penetration Using Data Mining Techniques
Authors: Al-Hameedi Abo Taleb T. , Alkinani Husam H. , Dunn-Norman Shari , Flori Ralph E. , Alsaba Mortadha T. , Amer Ahmed S. , Al-Bazzaz Waleed H. 
Published: April 2019

AbstractThe rate of penetration (ROP) plays a major role in reducing drilling costs, making it an important area of investigation. There are various controllable and uncontrollable factors that affect the ROP, and the variation in these variables affecting the ROP made it a very pivotal drilling parameter that has a significant effect on non-productive time. In this work, sensitivity and statistical analysis were carried out using data from over 1000 wells in Basra oil fields, Iraq. The scope of this work is to determine the effect of rheological properties on ROP, to provide a method for estimating the recommended range for drilling fluid properties based on data mining techniques.In this work, huge real field data from over 1000 wells drilled in Basra oil fields, Iraq were gathered and analyzed to better understand the characteristics of a drilling fluid that enhance ROP and quantify the impact of each drilling fluid rheological properties on ROP. The data used in this study were collected from mud logging data, daily drilling reports (DDR), and geological information. Statistical and sensitivity analyses were performed in order to identify the relationship between ROP and drilling fluid rheological properties. The correlation coefficient (CC) was utilized to understand the effect of solid content (SC), yield point (Yp), and plastic viscosity (PV) on ROP. The results showed that SC is the most influential rheological property on ROP, then PV and finally Yp. In addition, this work demonstrates how bit hydraulics can be improved by means of modifying the rheological properties rather than adjusting the flow rate or nozzle size.Large-scale collection and interpretation of field data or in other words "data mining" can be considered as a strong tool in understanding the impact of different parameters on the ROP in order to estimate the recommended range of rheological properties, which will result in improving the ROP.
Research and Application of the Big Data Analysis Platform of Oil and Gas Production
Authors: Zhao Ruidong , Shi Junfeng , Zhang Xishun , Li Jinya , Peng Yi , Xiong Chunming , Liu Meng , Deng Feng , Song Shenggang , Miao Guojing 
Published: April 2019

Abstract
With the continuously progressing of building the intelligent oilfield and the rapid development of the Internet of Things and big data technology, the emerging technologies such as the information acquisition, distributed computing and data mining lead to unceasing innovation in the research and development and management approaches of enterprises. A technical revolution also occurs in the petroleum industry. At present, one of the challenges we are facing is how to keep the advantages of the conventional oil and gas production and combine them with the big data analysis to better serve the petroleum industry. Given the complexity and uncertainty and thus difficulty endowed in the conventional oil and gas production, one potential solution, based on the big data mining, is proposed. The big data clustering analysis can be used to evaluate the oil well, and the multi-variable sensitivity analysis can be visualized through the dimensionality reduction. Data processing, operation condition diagnosis, forecasting and warning, and multi-dimension multi-variable visualization analysis are the main functions that are achieved in our preliminarily-built big data analysis platform for the production of oil and gas wells. In the future, this platform will gradually transform form the "business model" into the "data model", which adopts various methods such as the statistical analysis, pattern recognition, clustering analysis and visualization to enable the intelligent diagnosis, forecasting and warning, and decision-making optimization and evaluation for the oil and gas well production, on the basis of the multi-dimension multi-source data. At last, it is anticipated that this platform should serve the oil and gas production and evolve into an effective method to improve the production, reduce energy consumption and decrease cost for the oilfield.
Experiments and Emulsion Rheology Modeling in an Electric Submersible Pump
Authors: Banjar Hattan , Zhang Hong-Quan 
Published: April 2019

Abstract
An Electric Submersible Pump (ESP) is studied experimentally with oil-water emulsion. Emulsion rheology inside the ESP is also studied and modeled at different oil and water fractions, ESP rotational speeds and temperatures, using a dimensional analysis on a set of parameters contributing to the emulsion rheology. Density and mass flowrate are measured using the mass flowmeter, while the emulsion effective viscosity is initially derived from the pipe viscometer (PV) installed downstream of the ESP. Effective viscosity values at the stage condition are corrected using an oil of known viscosity by correlating its viscosity to ESP average temperature. Watercut at the inversion point increases in case of contamination presence which directly affects the interfacial tension.
Modeled effective viscosity values for emulsion with medium viscosity are within 5% deviation from the experimental values. However, when low oil viscosity is used, the deviation becomes larger, mainly due to the instability of the emulsion which leads to inaccurate measurement of the effective viscosity at the PV. Instability is confirmed from the PV results, density measurements and visual observation through the transparent pipe or during sampling.
Further improvement of the model is needed by changing the parameters in a wider range, and possibly by including non-considered parameters such as salinity. Most of the parameters affecting the emulsion rheology are combined in one term which can be considered as a factor that corrects the effective viscosity of the emulsion.
RSS with Near-Bit GR Imaging Assist Accurate Steer Drilling in Shale Gas Project in Sichuan: A Fit-For-Purpose Solutions for Shale Gas Drilling Case Study
Authors: Zheng Ma Jia , Liu Xin , Zhao Jian Ping , Qiu Xun Xi , Fang Jian , Wang Xiong Fei , Zhao Jing Kai , Geng Gan 
Published: April 2019

Abstract
The Sichuan Basin is the major target for shale gas exploration in China because of its rich gas stored in unexploited black shale with multiple bed series. National Shale Gas Exploitation Areas have been established since 2012, the proved geological shale gas reserves is 9210×108 m3 and 90.25×108m3 annually output has been achieved by the end of 2017.
The operating Sichuan Basin shale gas area located in the major compression tectonic experienced multiple geological structure movements in Earth history, showing characteristics of high steep structure with faults greatly developed. It's proven that the key factors in exploiting these targets are well acknowledged by the efforts to land and expose the lateral within the sweet zone. To successfully place lateral in reservoirs from geological perspective must overcome challenges of high uncertainty structure identification to make soft landing and maximize horizontal exposure in the sweet zone.
While it comes to shale gas reservoir, to pave the way for fracture operation and achieve good well completion, the drilling requires a relative gentle well path, keeping well path inclination with limitation, which requires to make azimuth turning to achieve this.
To ensure the optimum placement of the well in sweet zone, the integration of rotary steerable drilling system (RSS) with borehole images measurements in real-time have been implemented with the employment of well placement technique.
The borehole image portrays structural profile while drilling whilst the rotary steerable drilling system provides accurate trajectory control. With the help of borehole image and proactive log correlation, the trajectory can be landed precisely into desired best quality reservoir, although the formation dip and actual target depth become much different with geological prognosis. During the lateral section, the trajectory was also controlled effectively in the high-quality reservoir despite of structural variation and reservoir property change. Through use of Fit-For-Purpose solution it effectively improves drilling efficiency and positively impacts well production. These achievements subsequently help to optimize wells deployment plan and wells with longer lateral horizontal section were planned for greater predictable production rate.
Pilot Test and Effect Evaluation for the Water Shutoff Technology with Concentric Tube in Horizontal Well of Bohai Oilfield
Authors: Zhang Guohao , Liu Zongbin , Li Yanlai , Jia Xiaofei , Sun Zhaobo , Lv Zuobin 
Published: April 2019

Abstract
In strong edge/bottom-water reservoir, unstable pressure drop and recovery degree in different horizontal well segments often lead to breakthrough of edge and bottom water, causing rapid water cut increase and productivity decrease, even burst water flood. Bohai LD oilfield was low-rising and strong edge/bottom-water reservoir with horizontal well pattern. Considering the status of LD Oilfield which was short of reliable water-controlling techniques during high water-cut stage, an applicative, effective and economical water control technology was urgently required.
In the present work, water breakthrough characteristic template of horizontal well had been established through studying water breakthrough features of horizontal well locating at high permeability zone based on the mechanistic model. At the same time, combined with numerical simulation study on actual reserviors and physical parameters in the horizontal interval, the water breakthrough position of horizontal well had been further confirmed. On the basis of above, the water shutoff technology with concentric tube had been studied. It was through inserting a piece of concentric tube with small diameter into horizontal segment of horizontal well and optimizing design parameters of concentric tube in accordance with horizontal section flow profile.
Through the water shutoff technology with concentric tube, all fluid production profiles of experimental well had been effectively improved in horizontal section, which attained the destination of oil production increment and water cut reduction. The average oil production of single well had been increased 40 m3/d in two experimental wells from 2012 to 2017 in LD Oilfield. The cumulative oil increment had reached 50,000 m3. The general water percentage had decreased by 18% from 99% to 81%.
The water shutoff technology with concentric tube in horizontal well possessed the advantages of simple operation, low implementation cost. The pilot test and corresponding effect shown in the present paper demonstrates that this newly developed technical method had great potential in stabilizing oil production and controlling water cut of horizontal well in high water cut stage of offshore edge/bottom-water oil reservoir.
Designing Cement Jobs for Success - Get it Right the First Time!
Authors: Tang Lik Jin , Combe Caroline , Wee Anson , Mohd Radzi Razif , Heu Tieng Soon , Ho Chen Nyap , Tan Kenneth 
Published: April 2019

Abstract
Early during the M Field well design phase, it was realized that cementing would be challenging due to tight downhole pressure margins, S-shaped well trajectories with long horizontal section and the need to isolate more than one reservoir. Recognising that cement remediation would be both expensive and having low probability of success, a structured approach focusing on designing the cement jobs for success and getting it right the first time was adopted. Criteria on barrier requirements were agreed upfront by an integrated team consisting of Production Technologists, Well Fluid Engineers, Well Engineers, Petrophysicists, Technical Authorities and cementing contractors.
Early engagement allowed ample time for the team to agree on the mitigation measures for different cementing outcomes before the actual execution, thus avoiding potentially difficult decisions to be made on the fly. Cementing scorecards were populated with planned job parameters for each well. Mud removal and cement placement modelling was performed to get the optimal mud displacement to reduce the risk of channeling. If the modelling showed presence of channels and/or insufficient cement height, a re-design of the cement job was triggered. In the event that a satisfactory cement design cannot be achieved using the conventional methods, new technologies, such as dual stage cementing and managed pressure cementing, were implemented to increase the chances of getting good cement.
Once section target depth (TD) was reached, the scorecard and mud removal model were updated with the actual hole conditions. Adjustments in pumping rate, spacer and cement volumes and mud rheology were made to ensure an effective mud displacement and success cement job.
After pumping the cement, the scorecard and mud removal model were updated again and compared with the post job execution data such as theoretical top of cement (TTOC), lift pressure and pressure matching. Cement evaluation logs were obtained for the first three wells to calibrate the scorecard and mud removal model. For subsequent wells, cement evaluation logs were only carried as a contingency in the event that the theoretical top of cement did not meet the requirement. A cementing lookback was conducted post cement pumping and learnings were implemented for subsequent jobs. Over the drilling campaign, 18 casing strings were cemented and only two of those did not achieve the required top of cement height.
Designing the cement jobs for success and getting it right the first time provided significant cost saving on cement evaluation logging and on remediation while achieving the required lifecycle well integrity. This can only be achieved through a structured approach, early engagement and collaboration of an integrated and multidisciplinary team.
The Study and Application of the Kirchhoff Q PSDM Technology
Authors: Zhang Weiyi , Zhang Jianlei , Wang Chengxiang , Sun Pengyuan , Ma Yuanming , Xue Guiren 
Published: April 2019

Abstract
The Kirchhoff Q PSDM technique is studied in this paper in order to compensate the amplitude and correct the distortion of phase due to seismic attenuation in the earth, during the seismic waves traveling through the earth, especially through the the gas cloud region, to improve the resolution of the imaging results, and to satisfy the requirements of industrial production. In order to improve the calculation efficiency of the QPSDM, a time domain interpolation strategy is also proposed. This strategy avoids the compensation in frequency doamin at each imaging point, which is time-consuming. The computation efficiency of Q migration has been greatly improved with our method, making the Kirchhoff QPSDM able to meet the needs of industrial production. By analyzing the sources of the high frequency noise, the time-variant gain-limits are used to suppress the high frequency noise in the compensation procedure. The numerical results show that the compensation method using the time-variant gain-limits can effectively compensate the energy of the severe attenuation region while suppressing the high-frequency noise. Finally, we test the QPSDM approach on synthetic data and field data. These examples demonstratethat the QPSDM approach could produce higer resolution images with imporoved amplitude and correct phase compared to the convetional PSDM. The Kirchhoff QPSDM technology realized in this paper has produced desirable seismic images while it is applied in many exploration areas such as Dagang, Daqing, Malaysia, Nanhai, etc.