Flow Units in Shale Condensate Reservoirs

2016 ◽  
Vol 19 (03) ◽  
pp. 450-465 ◽  
Author(s):  
Bruno A. Lopez Jimenez ◽  
Roberto Aguilera
Keyword(s):  
Economic Benefits ◽  
Positive Side ◽  
Flow Units ◽  
Speed Flow ◽  
Shale Reservoir ◽  
Shale Reservoirs ◽  
Shale Oil Reservoirs ◽  
Favorable Conditions ◽  
Gas Tight ◽  
Process Speed

Summary Recent work has shown that flow units characterized by process or delivery speed (the ratio of permeability to porosity) provide a continuum between conventional, tight-gas, shale-gas, tight-oil, and shale-oil reservoirs (Aguilera 2014). The link between the various hydrocarbon fluids is provided by the word “petroleum” in “Total Petroleum System” (TPS), which encompasses liquid and gas hydrocarbons found in conventional, tight, and shale reservoirs. The work also shows that, other things being equal, the smaller pores lead to smaller production rates. There is, however, a positive side to smaller pores that, under favorable conditions, can lead to larger economic benefits from organic-rich shale reservoirs. This occurs in the case of condensate fluids that behave as dry gas in the smaller pores of organic-rich shale reservoirs. Flow of this dry gas diminishes the amount of liquids that are released and lost permanently in a shale reservoir. Conversely, this dry gas can lead to larger recovery of liquids in the surface from a given shale reservoir and consequently more attractive economics. This study shows how the smaller pores and their associated dry gas can be recognized with the use of process speed (flow units) and modified Pickett plots. Data from the Niobrara and Eagle Ford shales are used to demonstrate these crossplots. It is concluded that there is significant practical potential in the use of process speed as part of the flow-unit characterization of shale condensate reservoirs. This, in turn, can help in locating sweet spots for improved liquid production. The main contribution of this work is the association of flow units and different scales of pore apertures for improving recovery of liquids from shale reservoirs.

Flow Units: From Conventional to Tight-Gas to Shale-Gas to Tight-Oil to Shale-Oil Reservoirs

2014 ◽  
Vol 17 (02) ◽  
pp. 190-208 ◽  
Author(s):  
Roberto Aguilera
Keyword(s):  
Shale Gas ◽  
Oil Reservoirs ◽  
Petroleum Engineering ◽  
Tight Oil ◽  
Shale Oil ◽  
Transition Flow ◽  
Flow Units ◽  
Shale Oil Reservoirs ◽  
Porosity Model ◽  
Process Speed

Summary Core data from various North American basins with the support of limited amounts of data from other basins around the world have shown in the past that process speed or delivery speed (the ratio of permeability to porosity) provides a continuum between conventional, tight-, and shale-gas reservoirs (Aguilera 2010a). This work shows that the previous observation can be extended to tight-oil and shale-oil reservoirs. The link between the various hydrocarbon fluids is provided by the word “petroleum” in the “total petroleum system (TPS),” which encompasses liquid and gas hydrocarbons found in conventional, tight, and shale reservoirs. Results of the present study lead to distinctive flow units for each type of reservoir that can be linked empirically to gas and oil rates and, under favorable conditions, to production decline. To make the work tractable, the bulk of the data used in this paper has been extracted from published geologic and petroleum-engineering literature. The paper introduces an unrestricted/transient/interlinear transition flow period in a triple-porosity model for evaluating the rate performance of multistage-hydraulically-fractured (MSHF) tight-oil reservoirs. Under ideal conditions, this flow period is recognized by a straight line with a slope of –1.0 on log-log coordinates. However, the slope can change (e.g., to –0.75), depending on reservoir characteristics, as shown with production data from the Cardium and Shaunavon formations in Canada. This interlinear flow period has not been reported previously in the literature because the standard assumption for MSHF reservoirs has been that of a pseudosteady-state transition between the linear flow periods. It is concluded that there is a significant practical potential in the use of process speed as part of the flow-unit characterization of unconventional petroleum reservoirs. There is also potential for the evaluation of production-decline rates by the use of the triple-porosity model presented in this study.

scholarly journals Factors Controlling Shale Reservoirs and Development Potential Evaluation: A Case Study

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Chao Luo ◽  
Hun Lin ◽  
Yujiao Peng ◽  
Hai Qu ◽  
Xiaojie Huang ◽  
...  
Keyword(s):  
Shale Gas ◽  
Mineral Content ◽  
Gas Content ◽  
Longmaxi Formation ◽  
Development Potential ◽  
Reservoir Characteristics ◽  
Lower Silurian ◽  
Single Well ◽  
Shale Reservoir ◽  
Shale Reservoirs

The shale of the Lower Silurian Longmaxi Formation is an important gas-producing layer for shale gas development in southern China. This set of shale reservoir characteristics and shale gas development potential provide an important foundation for shale gas development. This study takes wellblock XN111 in the Sichuan Basin, China, as an example and uses X-ray diffraction (XRD), scanning electron microscopy (SEM), isothermal adsorption, and other techniques to analyze the shale reservoir characteristics of the Lower Silurian Longmaxi Formation. The results show that the Lower Silurian Longmaxi Formation was deposited in a deep-water shelf environment. During this period, carbonaceous shale and siliceous shale characterized by a high brittle mineral content ( quartz > 40   wt . % , carbonate   mineral > 10   wt . % ) and a low clay mineral content (<30 wt.%, mainly illite) were widely deposited throughout the region. The total organic carbon (TOC) content reaches up to 6.07 wt.%, with an average of 2.66 wt.%. The vitrinite reflectance is 1.6–2.28%, with an average of 2.05%. The methane adsorption capacity is 0.84–4.69 m3/t, with an average of 2.92 m3/t. Pores and fractures are developed in the shale reservoirs. The main reservoir space is composed of connected mesopores with an average porosity of 4.78%. The characteristics and development potential of the shale reservoirs in the Lower Silurian Longmaxi Formation are controlled by the following factors: (1) the widespread deep-water shelf deposition in wellblock XN111 was a favorable environment for the development of high-quality shale reservoirs with a cumulative thickness of up to 50 m; (2) the high TOC content enabled the shale reservoir to have a high free gas content and a high adsorptive gas storage capacity; and (3) the shale’s high maturity or over maturity is conducive to the development of pores and fractures in the organic matter, which effectively improves the storage capacity of the shale reservoirs. The reservoir characteristic index was constructed using the high-quality shale’s thickness, gas content, TOC, fracture density, and clay content. Using production data from shale gas wells in adjacent blocks, a mathematical relationship was established between the Estimated Ultimate Recovery (EUR) of a single well and the Reservoir Characteristics Index (Rci). The EUR of a single well in wellblock XN111 was estimated.

scholarly journals CUSTOMER SERVICE IN FINANCIAL INSTITUTIONS: ASPECTS OF PARTNER MARKETING

2021 ◽  
Author(s):  
Olha Hirna ◽  
Iryna Darmogray
Keyword(s):  
Customer Service ◽  
Banking System ◽  
Internet Banking ◽  
Economic Benefits ◽  
Customer Base ◽  
Active Population ◽  
Positive Side ◽  
Positive Elements ◽  
Bank Card ◽  
Internet Banking System

The article describes the main aspects of improving customer service of the bank using elements of affiliate marketing. The formation of high attractiveness of the bank for the client by establishing strategically promising partnership relations presents the formation of high attractiveness of the bank for the client. The bank expects long-term economic benefits, and the client expects to receive an acceptable level of service. The main aspects of KREDOBANK JSC activity are analyzed, and it is noted that the bank is a leader in providing banking services in Western Ukraine. These services include retail and business lending, bank card and account servicing, valuables storage services, and more. To assess the current situation regarding the customer base and establish partnerships with customers, increase the attractiveness of JSC "KREDOBANK" conducted a survey of retail customers on the basis of questionnaires. Based on the analysis of the survey results, the strengths and weaknesses of the studied bank were identified. The positive side is that most of the bank's customers are economically active people with stable monthly incomes. At the same time, new opportunities were identified to attract new clients, namely student youth. This category of the population in the future, with a well-formed policy of the bank in terms of customer service, may become its customers in the segment of the economically active population. Therefore, a new package of services "Student" was developed and proposed, which on the basis of the existing tariff package of the bank, provides lower tariffs, reduced commission for transactions, lower interest on a loan for small amounts, extended grace period when using an overdraft. As a result of the study, along with the positive elements (staff competence, level of communication, bank reliability), such negative trends in customer service as low speed of customer service, lack of understanding of customer needs (in some cases). In order to eliminate these negative elements and increase the level of customer service, it is proposed to improve the existing Internet banking system. These improvements apply to the mobile application: it is proposed to update its design, expand functionality, eliminate malfunctions.

An Integrated Petrophysics and Geomechanics Approach for Fracability Evaluation in Shale Reservoirs

SPE Journal ◽  
2015 ◽  
Vol 20 (03) ◽  
pp. 518-526 ◽  
Author(s):  
Xiaochun Jin ◽  
Subhash N. Shah ◽  
Jean-Claude Roegiers ◽  
Bo Zhang
Keyword(s):  
Hydraulic Fracturing ◽  
Horizontal Well ◽  
Reservoir Characterization ◽  
Rock Strength ◽  
Barnett Shale ◽  
Dolomitic Limestone ◽  
Well Drilling ◽  
Shale Reservoir ◽  
Shale Reservoirs ◽  
Definition Of

Summary The identification of the fracture barrier is important for optimizing horizontal-well drilling, hydraulic fracturing, and protecting fresh aquifer from contamination. The word “brittleness” has been a prevalent descriptor in unconventional-shale-reservoir characterization, but there is no universal agreement regarding its definition. Here, a new definition of mineralogical brittleness is proposed and verified with two independent methods of defining brittleness. Formation with higher brittleness is considered as a good fracturing candidate. However, this viewpoint is not reasonable because brittleness does not indicate rock strength. For instance, the fracture barrier between upper and lower Barnett can be dolomitic limestone with higher brittleness. A new fracability index (FI) is introduced to overcome the shortcoming of brittleness by integrating both brittleness and energy dissipation during hydraulic fracturing. This FI considers that a good fracturing candidate is not only of high brittleness, but also requires less energy to create a new fracture surface. Therefore, the formation with lower FI is considered as a bad fracturing candidate, whereas that with higher fracability is considered as a better target. Logging data from one well in the Barnett shale are applied (1) to verify the principle of the new brittleness definition and FI model and (2) to demonstrate the process of screening hydraulic-fracturing candidates with the FI model.

Geo-Engineered Completion Optimization: An Integrated, Multi-Disciplinary Approach to Improve Stimulation Efficiency in Unconventional Shale Reservoirs

2015 ◽  
Author(s):  
David R. Spain ◽  
Ivan Gil ◽  
Herb Sebastian ◽  
Phil S. Smith ◽  
Jeff Wampler ◽  
...  
Keyword(s):  
Large Scale ◽  
Horizontal Well ◽  
State Of The Art ◽  
Economic Benefits ◽  
Production Performance ◽  
No Production ◽  
Natural Fractures ◽  
Well Performance ◽  
Shale Reservoirs

Abstract Large, high density fracture networks are necessary to deliver commercial production rates from sub-microdarcy permeability organic-rich shale reservoirs. Operators have increased lateral length and fracture stages as the primary means to improve well performance and, more recently, are tailoring completion techniques to local experience and reservoir-specific learning. In particular, closer fracture stage spacing or increased number of stages per well have driven improvements in well performance. Large scale adoption occurs when the change in performance is clearly linked to the reservoir-specific completion design. Horizontal well fracturing efficiency in unconventional reservoirs is notoriously poor. Numerous authors report that 40 to 60 per cent of frac stages or individual perforation clusters have been shown (albeit with highly uncertain surveillance methods) to contribute little or no production. The fracture initiation and propagation process is very complex in shale; it is affected by in-situ stress, geomechanical heterogeneity, presence of natural fractures, and completion parameters. Close cluster spacing can provide enhanced well production; however, if the spacing is too close, stress shadowing among these clusters can actually induce higher stresses, creating fracture competition. This paper presents an approach to the integration of these parameters through both state-of-the-art geological characterization and unconventional 3D hydraulic fracture modeling. We couple stochastic discrete fracture network (DFN) models of in-situ natural fractures with a state-of-the art 3D unconventional fracture simulator. The modeled fracture geometry and associated conductivity is exported into a dynamic reservoir flow model, for production performance prediction. Calibrated toolkits and workflows, underpinned by integrated surveillance including distributed temperature and acoustic fiber optic sensing (DTS/DAS), are used to optimize horizontal well completions. A case study is presented which demonstrates the technical merits and economic benefits of using this multidisciplinary approach to completion optimization.

Artificial Intelligence Approach for Predicting TOC From Well Logs in Shale Reservoirs

2020 ◽  
pp. 46-77 ◽  
Author(s):  
Md. Shokor A. Rahaman ◽  
Pandian Vasant
Keyword(s):  
Oil And Gas ◽  
Hydrocarbon Generation ◽  
Oil And Gas Exploration ◽  
Direct Measurements ◽  
No Free Lunch Theorem ◽  
Shale Reservoir ◽  
Shale Reservoirs ◽  
Low Dimensional ◽  
No Free Lunch ◽  
Intelligence Approach

Total organic carbon (TOC) is the most significant factor for shale oil and gas exploration and development which can be used to evaluate the hydrocarbon generation potential of source rock. However, estimating TOC is a challenge for the geological engineers because direct measurements of core analysis geochemical experiments are time-consuming and costly. Therefore, many AI technique has used for TOC content prediction in the shale reservoir where AI techniques have impacted positively. Having both strength and weakness, some of them can execute quickly and handle high dimensional data while others have limitation for handling the uncertainty, learning difficulties, and unable to deal with high or low dimensional datasets which reminds the “no free lunch” theorem where it has been proven that no technique or system be relevant to all issues in all circumstances. So, investigating the cutting-edge AI techniques is the contribution of this study as the resulting analysis gives top to bottom understanding of the different TOC content prediction strategies.

High-quality marine shale reservoir prediction in the lower Silurian Longmaxi Formation, Sichuan Basin, China

2020 ◽  
Vol 8 (2) ◽  
pp. T453-T463
Author(s):  
Shang Xu ◽  
Fang Hao ◽  
Yuanyin Zhang ◽  
Qiyang Gou
Keyword(s):  
Sichuan Basin ◽  
Reservoir Prediction ◽  
High Quality ◽  
Development Zone ◽  
Lower Silurian ◽  
Marine Shale ◽  
Impedance Inversion ◽  
Shale Reservoir ◽  
Shale Reservoirs ◽  
Zero Offset

For the lower Silurian Longmaxi marine shale reservoir in the Jiaoshiba area, Sichuan Basin, China, the traditional P-impedance ([Formula: see text]) is insensitive for predicting good reservoirs. As an integral indicator of borehole radioactivity that is substantially corresponding to the organic richness, the uranium curve is qualified to identify the abundance of organic matter. Therefore, to efficiently comprehend the shale distribution in the Jiaoshiba area, we have adopted a so-called pseudo-P-impedance ([Formula: see text]), which is constructed from the P-impedance and the uranium (U) log and spatially computed from impedance inversion of the zero-offset seismic. The [Formula: see text] log shows an obvious correlation with the organic richness of the shale. The thickness of the high-quality shale derived from the inverted [Formula: see text] cube shows a higher correlation with the log data compared to the traditional P-impedance cube. The distribution of predicted high-quality shale is strongly influenced by the fault systems: (1) Although the fault development zone might lead to a distorted image of the seismic and weak shale evaluation, the shale gas cannot be efficiently preserved in these places, and (2) high-quality shale reservoirs are mainly distributed in the not-faulted area and show a general northeast–southwest trend. Generally, the introduced [Formula: see text] inversion is suitable for the seismic frequency range and could be applied to other similar exploration areas.

Quantitative identification of microfractures in the marine shale reservoir of the Wufeng-Longmaxi Formation using water immersion tests and image characterization

2018 ◽  
Vol 6 (4) ◽  
pp. SN23-SN30 ◽  
Author(s):  
Hu Wang ◽  
Zhiliang He ◽  
Yonggui Zhang ◽  
Kun Su ◽  
Ruyue Wang
Keyword(s):  
Water Immersion ◽  
Fracture Network ◽  
Gas Field ◽  
Reservoir Evaluation ◽  
Computed Tomography Scanning ◽  
Immersion Testing ◽  
Shale Reservoir ◽  
Shale Reservoirs ◽  
Southeastern Sichuan Basin ◽  
Scanning Electron

Identification of natural microfractures is important for shale reservoir evaluation. In total, 42 selected core samples from the Wufeng-Longmaxi marine shales in the Fuling gas field, southeastern Sichuan Basin, were analyzed using water-immersion testing, computed tomography scanning, and argon-ion polishing scanning electron microscope experiments, along with edge detection and image stitching analysis methods. The results indicate that the immersion experiment is an effective way to identify natural fractures. Three types of natural microfractures correspond to bubble positions with 250 nm resolution scanning electron microscopy: bedding fractures, particle edge fractures, and dissolution fractures. The bedding and dissolution fractures show the same occurrence as the strata, and they are the main bubbling channels. The occurrence of particle edge fractures varies significantly. Microfractures are capable of forming a fracture network, connecting separated storage spaces in the shale reservoir. The best fracture network is formed by bedding and dissolution fractures in 3D space. Furthermore, apportion of the particle edge and dissolution fractures is capable of forming microfracture networks in shale cores increasing the connectivity of pore spaces. The number of bubble points also indicates a positive correlation with shale laminae, which indicates that microfractures are developed mainly within the laminae. The number of shale laminae and the number of microfracture channels can be calculated quantitatively by the number of bubble points. The observations can be used in the drilling site to estimate the physical properties of shale reservoirs quickly and quantitatively.

scholarly journals The value of human dignity as a form of moral regulation of teacher’s actions and deeds

2020 ◽  
Vol 9 (4) ◽  
pp. 272-277
Author(s):  
Vladimir Petrovich Bezdukhov ◽  
Artyom Vladimirovich Bezdukhov
Keyword(s):  
Golden Rule ◽  
Point Of View ◽  
Social Relevance ◽  
Moral Regulation ◽  
Positive Side ◽  
Constructive Dialogue ◽  
Moral Quality ◽  
Moral Qualities ◽  
Education Of Students ◽  
Favorable Conditions

The relevance of the research is motivated by the importance of understanding the value of dignity as one of the forms of moral regulation of the teachers actions and deeds. The authors motivate the social relevance of teaching a moral quality (or virtue) of dignity by the fact that, considering him/herself and others equally worthy, a person becomes capable of a constructive dialogue. The paper argues that one of the leading goals of modern education as an introduction to values is the education of students self-esteem, the upbringing of worthy people. The authors reveal that value is one of the elements of the system of moral regulation of actions and deeds; that the imperativeness of values lies in the fact that, being a guideline for pedagogical activity, they instruct the teacher to correspond to their content, which determines the content of moral requirements for him/herself and for students. It is shown that the golden rule of morality as a value determines the most important form of moral regulation in modern conditions. It is revealed that positive or negative aspects of the golden rule of morality correspond to what the teacher wants or does not want to experience, endure; what action he/she wants (does not want) to do so that students do (dont do) the same. It is substantiated that the above-mentioned aspects of the golden rule of morality from the pedagogical point of view are requirements to act (requirements-samples) or not to act (requirements-prohibitions) accordingly. It is revealed that dignity as a virtue combines the elements of obligation and value. Obligation is manifested in behavior focused on a certain moral quality dignity; the value of dignity, which manifests itself in behavior through the manifestation of moral qualities of honesty, truthfulness, etc., sets the form of moral regulation in which (form) the content of moral qualities and value of dignity is transmitted. The authors of the paper insist that the teacher, in the course of interaction with students, creates conditions for them to understand the essence of requirements-prohibitions, contained in the negative side of the golden rule of morality, and the essence of requirements-samples, enclosed in the positive side of the golden rule of morality; that at the level of self-education, these requirements are formulated by the teacher and students in the form of self-persuasion, self-order to commit a moral deed and not to commit an immoral act. Self-persuasion and self-order are methods of self-education, and the more a person masters them, the more he/she strengthens self-respect. Such a person becomes a moral guide for others; such a teacher creates the most favorable conditions for developing students self-respect.

scholarly journals Study on the evaluation method and influencing factors of fracture conductivity of hydraulic fracturing support in shale reservoir

2021 ◽  
Vol 252 ◽  
pp. 03049
Author(s):  
Yin Shun-li ◽  
Zhuang Tian-lin ◽  
Yang Li-yong ◽  
Jia Yun-peng ◽  
Liu Xue-wei ◽  
...  
Keyword(s):  
Hydraulic Fracturing ◽  
Evaluation Method ◽  
Guar Gum ◽  
Great Influence ◽  
Clay Content ◽  
Fracturing Fluid ◽  
Fracture Conductivity ◽  
Shale Reservoir ◽  
Shale Reservoirs ◽  
Proppant Embedment

The conductivity of supporting fractures is an important parameter to evaluate the hydraulic fracturing effect of shale reservoirs, and its size is affected by many factors. In this paper, the proppant is optimized and evaluated on the basis of real rock slab simulation and actual construction proppant test. The laboratory experimental study on the influence of proppant type, sand concentration, proppant embedding and fracturing fluid residue on propping fracture conductivity is carried out, the results show that the average conductivity of 40 / 70 mesh proppant is about 7.15d · cm at 5kg / m2 sand concentration under the condition of reservoir closure pressure of about 50MPa, which can basically meet the requirements of main fracture conductivity of Kong 2 shale reservoir in Dagang Oilfield; the damage of guar gum fracturing fluid and proppant embedment are two important factors that cause the great decline of conductivity of rock slab, and the damage of guar gum fracturing fluid has a great influence on the conductivity, reaching about 50%; the stronger the mud is (the higher the clay content is), the greater the embedment degree of proppant is, and the greater the loss of conductivity is; for the same lithology, the proppant particle size has little damage to the conductivity, and the sand concentration has a greater impact on the conductivity. The larger the sand concentration is, the smaller the loss of the conductivity is.

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