She received her bachelor’s and master’s degrees in 2006 and 2009, with concentrated studies in mechanical engineering and energy conversion. She interned as a reservoir engineer with InPetro Technologies Inc. in 2014 and worked as a petroleum engineer, performing diagnostic fracture injection testing analysis for Hess Corporation in 2011. Nojabaei co-authored a paper, “Modeling Wellbore Transient Fluid-Temperature and Pressure During Diagnostic Fracture Injection Testing in Unconventional Reservoirs” that was published in 2014 in the Journal of Canadian Petroleum Technology. In 2013, her paper, “Effect of Capillary Pressure on Phase Behavior in Tight Rocks and Shales” became one of the top downloads of SPE’s OnePetro website. Looking ahead, Nojabaei wants to concentrate her career in comprehensive, long-term university research in reservoir engineering.
Session 1: Start-Up: What's Hot, What Should be Hot In this opening session, we provide some (recent) historical perspectives and developments. In addition, we consider "what's hot, what's not" topics such as single versus multi-well performance analyses, assessment of completions efficiency/effectiveness from well performance data, etc. We also consider "next phase" technologies/methodologies for PTA, RTA, and DCA with an invited speaker(s). Lastly, the ATW co-chairs provide orientation and expectations for the workshop. This session discusses the incorporation of petrophysical heterogeneity, fluid-phase intricacies, and geometrical complexity of unconventional reservoirs in advanced models for PTA/RTA.
This workshop focuses on the use of pressure transient analysis (PTA) for short-term data and Rate Transient Analysis (RTA) for long-term production rate and pressure data in order to characterize the performance of wells in unconventional reservoirs. Much has been published regarding issues with interpretation of flow regimes, estimation of individual and lumped reservoir parameters (e.g., the fracture half-length-square root of formation permeability product estimated from linear flow data), forecasts of production rate performance, as well as correlation of performance indices with completions parameters for unconventional reservoirs. As such, this workshop focuses on case histories and best practices.
Production optimization has become currently one of the most critical aspects for well/reservoir management. This course will cover the following aspects: Nodal Analysis, Formation Damage, Quantification of Formation Damage, Pressure Transient Analysis, Intervention Benefit, and Artificial Lifting (ESP). Every oil company, National, International or an independent company is working on achieving their economic goals by optimizing well deliverability. In this training participants will learn how to evaluate actual well performance and how to optimize well deliverability. Fabio Gonzalez is currently a Reservoir Engineering Advisor with BP on assignment in Kuwait.
This course entails estimating reserves in diverse reservoir settings. The participants will gain insights into several established methods, such as material-balance analysis (MBA), decline-curve analysis (DCA), and rate-transient analysis (RTA) for estimating the in-place volume associated with a given well in actual field settings, wherein various drive mechanisms may be in play. The discussion will also entail regulatory guidelines of SEC and the general guidance offered by SPE-sponsored Petroleum Resources Management System (PRMS). This half-day course emphasizes understanding of various analytical tools for understanding flood performance, leading to the assessment of remaining reserves. Specifically, we use the water-oil/watergas ratio type curve and the reciprocal-PI plot for monitoring flood performance at individual producers.
Pressure transient data may be acquired from wells during exploration, appraisal and production. Each data set provides important dynamic information that facilitates the decision making process at the various phases of reservoir development. The course will summarize the fundamentals of pressure transient analysis and discuss some of the recent advances including deconvolution. Emphasis will be placed on the value of information. It will combine explanations of theory (including course notes), worked examples (using Excel) and presentation of real case examples from both oil and gas reservoirs.
For the unconventional reservoir, triple-porosity models are widely applied to take the macro-fracture, micro-fracture and matrix system into consideration. However, the models are usually built based on the assumption of sequential flow from matrix to micro-fracture to macro-fracture, which will result in inaccuracy of production evaluation. Although a quadri-linear flow model (QFM) has been proposed to consider the simultaneous flow from matrix into micro-fracture and macro-fracture. It is relatively complicated to solve the model with the Laplace transform and numerical inversion. In this paper, a new analytical solution for the QFM is derived.
In order to simplify the problem, the matrix flow is divided into two parts: one feeding the macro-fracture and the other feeding the micro-fracture. Then, four partial differential equations (PDEs) are obtained to express the transient linear flow in different media. The PDEs are transformed into ordinary differential equations (ODEs) by integration bypassing the Laplace transform and numerical inversion. Finally, a rate vs. time solution in real-time space is derived.
The results are validated by typical analytical models. While the micro-fracture system is neglected, the results agree well with the dual-porosity model. While ignoring flow between the matrix and macro-fracture, the results agree with the triple-porosity model. What’s more, according to the output parameters from the new model, one can infer the ratio of pore volume of different media and even the ratio of flow from matrix to the micro-fracture and to the macro-fracture simultaneously. The model is also applied to analyze the field production data. After identifying the flow regime, the solution can match well with the data and the model parameters can be obtained. Through the parameters, we can make production forecast accurately.
Formation pressure and sampling measurements in low mobility formations under dynamic filtration can lead to measurements influenced by continuous mud circulation. Generally, active mud circulation inhibits mud cake growth, promoting filtration and invasion of mud filtrate into the reservoir. The resulting invasion adds its own pressure to the actual formation pressure. This is more pronounced in low mobility formations where pressure or sampling measurements made with mud circulation show higher than expected reservoir pressures and/or extended clean up times as a result of dynamic filtration and invasion.
We focus on formation pressure acquisition and present data sets where pressure acquisition was done with active mud circulation. The data is then compared with measurements acquired in a pseudo-static and static mud column.
The measured near wellbore formation pressures acquired with active mud filtration are significantly higher (in some cases, > 400psi) compared to those obtained with a static mud column (assumed to be reading closer to the true formation pressure). The additional pressure is often referred to as supercharging, i.e., the excess pressure superimposed on the original formation pressure by the viscous flow of mud filtrate. The difference depends amongst other factors primarily on the formation mobility and surface pump flow rate during the pressure acquisition. For higher mobilities, there is generally little appreciable difference between active mud circulation and zero mud circulation. Secondary factors like pipe movement, pipe diameter, mud composition and reservoir wettability also influence the degree of the extra pressure measured.
Best practices for formation testing while drilling in low mobility carbonates are discussed. Lessons are drawn from experience where ignoring such best practices result in questionable data.
Building accurate reservoir models can be quite challenging, especially highly stratified thick intervals in hydraulic communication in reservoir. Presented methodology is based on comprehensive Interval and Interference Pressure Transient Testing (IIPTT) for classified reservoir types with a systematic approach. Classification of reservoir types is based on layering, thickness, and hydraulic communication of layers in the reservoir. The methodology describes building more accurate anisotropic reservoir models, providing well performance assessment based on integrated comprehensive IIPTT solving with efficient nonlinear parameter estimation and modeling with numerical simulation for different reservoir types. The number distributed IIPTTs are optimized to ensure to achieve coverage across total thickness depending on the reservoir type. It is demonstrated that high resolution accurate reservoir models can be built for relatively thick highly layered reservoirs in a feasible manner.
The optimization of well spacing has become more important in unconventional shale reservoirs to efficiently design infill developments, estimate the Stimulated Reservoir Volume (SRV), and more importantly the estimation of Ultimate Oil Recovery (EUR) from each well. This paper presents a new analytical solution to estimate the start and end of pseudo-transient flow for the data production analysis where boundary-dominated flow exists in the induced fractures hence estimate the SRV for hydraulically fractured horizontal wells for unconventional shale reservoirs.
This paper presents a semi-analytical model to obtain the pressure transient response to characterize the flow and estimate the boundary effect which can be used to analyze the field data in unconventional shale reservoirs. The results from the model are compared and validated against an in-house developed numerical simulation model. The semi-analytical model is based on trilinear model where the SRV is modeled using dual-porosity idealization. The developed model involves the simulation of interference tests for two hydraulically-fractured horizontal well in unconventional shale reservoir using the real-time distributed pressure data. The proposed asymptotic solution evaluates not only the pseudo-transient in induced fractures but also the matrix.
The pressure measurements from real-time distributed pressure sensors and the production measurement using interference test provide a better understanding of the physical phenomena of the interaction between the parent and child wells in shale reservoirs. This paper presents a new model to assess the interference characteristics in horizontal wells to evaluate the optimum well spacing in unconventional shale reservoirs. It is observed that the production from a well is greatly affected by the distance of the wells, the reservoir properties between the wells, and the matrix permeability. It is presented that if the matrix permeability is lower, the start of the pseudo transient flow is sooner; therefore, the drainage volume becomes smaller. This can be observed by comparing the field data from unconventional shale reservoirs in Bakken and Eagle Ford where the matrix permeability in Bakken is higher than that of the Eagle Ford; therefore, the wells observe longer linear flow regime in higher permeability with larger SRV and in-turn larger well-spacing. The proposed asymptotic solution can also be used to analyze the field data in unconventional shale reservoirs to decipher the productivity and economics of horizontal wells.
To effectively produce from unconventional shale reservoirs, an optimum well spacing is required. This paper presents a novel asymptotic solution to characterize the flow regimes and provide a novel formulation in analyzing the pressure and rate variation with time to forecast future performance.