Fractured zones detection using conventional petrophysical logs by differentiation method and its correlation with image logs

Aghli, Ghasem; Soleimani, Bahman; Moussavi‐Harami, Reza; Mohammadian, Ruhangiz

doi:10.1016/j.petrol.2016.02.002

Cited by 82 publications

(17 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The R(n)/S(n) values of the logging parameters (e.g., GR, AC, DEN, and CAL logging) in target stratum and n are plotted as double logarithm scatter plots. If there is an obvious linear relationship between lgR(n)/S(n) and lgn, it indicates that the reservoir parameter sequence Especially when the shale thickness is small, the identifications are extremely inaccurate (Aghli, Soleimani, Moussavi-Harami, & Mohammadian, 2016;Howard, Irl, & Stephen, 2005). In order to accurately divide the concave parts of a curve, the quadratic derivative of the function is introduced in this study.…”

Section: Theory and Methodologymentioning

confidence: 99%

“…Eye recognition has great subjectivity in determining the concave parts of a curve, which will bring large errors to the results of fracture identification. Especially when the shale thickness is small, the identifications are extremely inaccurate (Aghli, Soleimani, Moussavi‐Harami, & Mohammadian, ; Howard, Irl, & Stephen, ). In order to accurately divide the concave parts of a curve, the quadratic derivative of the function is introduced in this study.…”

Section: Theory and Methodologymentioning

confidence: 99%

See 1 more Smart Citation

Application of R/S analysis in fracture identification of shale reservoir of the Lower Cambrian Niutitang Formation in northern Guizhou Province, South China

Ding

Luo

et al. 2019

Geological Journal

View full text Add to dashboard Cite

Natural fractures not only improve the physical properties of shale reservoirs but also promote the formation of hydraulic fracturing networks. The accurate identification of natural fractures in shale reservoirs is of a great significance to the exploration and development of shale gas. In this paper, the Lower Cambrian Niutitang Formation in Cen'gong block of northern Guizhou Province is taken as the research horizon. A variety of conventional logging parameters are selected to identify the natural fractures in the Niutitang Formation of three shale gas wells in the study area by combining R/S analysis method. Fracture locations can be accurately determined by calculating the second derivatives of lg(R/S) function. Considering the sensitivity of logging parameters to natural fractures, the analytic hierarchy process (AHP) is used to assign the corresponding weight to each logging parameter. A new parameter, fracture development coefficient, is introduced to quantitatively characterize the development degree of natural fractures. The results of R/S analysis are compared with those of core fracture observation and statistics. The results show that R/S analysis has a good effect on shale fracture identification, and the effect of fracture identification of three wells presents the following order: TM‐1 > TX‐1 > CY‐1. There is a positive correlation between fracture development coefficient and fracture linear density, indicating that the larger the fracture development coefficient is, the more developed the shale fractures are. Therefore, the fracture development coefficient can be used to characterize the degree of fracture development. In addition, we also analyze the errors of the identification results of R/S analysis and compare this method with conventional logging method. R/S analysis based on conventional logging is an accurate and efficient fracture identification method, which provides a new idea for the study and quantitative characterization of the natural fractures in shale reservoirs.

show abstract

Section: Theory and Methodologymentioning

confidence: 99%

Section: Theory and Methodologymentioning

confidence: 99%

Application of R/S analysis in fracture identification of shale reservoir of the Lower Cambrian Niutitang Formation in northern Guizhou Province, South China

Ding

Luo

et al. 2019

Geological Journal

View full text Add to dashboard Cite

show abstract

“…Electrical image logging tools that can evaluate the role of fractures in reservoir performance include the formation micro-imager (FMI) (Serra 1989;Schlumberger 2003) and the electrical micro-imager (EMI) (Halliburton 1996). As a result, fracture diagnosis remains merely qualitative, unless these tools are used to determine reservoir porosity and permeability (Aghli et al 2016;Hornby et al 1992;Lai et al 2017a;Martinez et al 2002). Most previous studies have focused on image logs for the identification of features in reservoir rocks (Khoshbakht et al 2009;Miller et al 2003;Zazoun 2013).…”

Section: Edited By Jie Hao and Xiu-qiu Pengmentioning

confidence: 99%

Reservoir heterogeneity and fracture parameter determination using electrical image logs and petrophysical data (a case study, carbonate Asmari Formation, Zagros Basin, SW Iran)

2019

Self Cite

View full text Add to dashboard Cite

Assessment of reservoir and fracture parameters is necessary to optimize oil production, especially in heterogeneous reservoirs. Core and image logs are regarded as two of the best methods for this aim. However, due to core limitations, using image log is considered as the best method. This study aims to use electrical image logs in the carbonate Asmari Formation reservoir in Zagros Basin, SW Iran, in order to evaluate natural fractures, porosity system, permeability profile and heterogeneity index and accordingly compare the results with core and well data. The results indicated that the electrical image logs are reliable for evaluating fracture and reservoir parameters, when there is no core available for a well. Based on the results from formation micro-imager (FMI) and electrical micro-imager (EMI), Asmari was recognized as a completely fractured reservoir in studied field and the reservoir parameters are mainly controlled by fractures. Furthermore, core and image logs indicated that the secondary porosity varies from 0% to 10%. The permeability indicator indicates that zones 3 and 5 have higher permeability index. Image log permeability index shows a very reasonable permeability profile after scaling against core and modular dynamics tester mobility, mud loss and production index which vary between 1 and 1000 md. In addition, no relationship was observed between core porosity and permeability, while the permeability relied heavily on fracture aperture. Therefore, fracture aperture was considered as the most important parameter for the determination of permeability. Sudden changes were also observed at zones 1-1 and 5 in the permeability trend, due to the high fracture aperture. It can be concluded that the electrical image logs (FMI and EMI) are usable for evaluating both reservoir and fracture parameters in wells with no core data in the Zagros Basin, SW Iran.

show abstract

“…Production logging tools are also used to analyze and investigate the borehole performances. Beside this tool monitors the borehole inefficiencies by interpreting production logs [14,15]. Fig.…”

Section: Production Logging Tools Componentsmentioning

confidence: 99%

Production Logging and its Implementation: A Technical Review

Chowdhury¹,

Tanjil²,

Akter³

et al. 2019

International Journal of Petroleum and Petrochemical Engineerin

View full text Add to dashboard Cite

Traditional well log determines the geological and geophysical data of the wellbore and formation fluids properties like porosity, permeability, saturation, resistivity and shale volume. All these are measured during exploration and development stages of a drilling hole. During production or injection of a well, several problems like lost circulation, production tubing integrity and such others need to be known which are very important. Production logging determines wellbore fluid flowing data during production of oil, gas or water. Production problems determination and the remedy of the problems are designed based on production logging. Several production logging tools are used to determine the flow behavior of the formation fluids as well as identification of the top of cement. For multi-layers reservoir, perforation is essential for producing oil or gas from several layers. Production log determines the location of perforation. Spinner flow meter is used to determine the formation fluids velocity whereas Gradiomanometer is for fluids density. Besides, individual sensors are used in production logging for appraisement of various properties. This paper provides a technical review on production logging and its tools along with the modification for horizontal well. The result of this study will help to understand the importance and technique of production log very effectively.

show abstract

Fractured zones detection using conventional petrophysical logs by differentiation method and its correlation with image logs

Cited by 82 publications

References 10 publications

Application of R/S analysis in fracture identification of shale reservoir of the Lower Cambrian Niutitang Formation in northern Guizhou Province, South China

Application of R/S analysis in fracture identification of shale reservoir of the Lower Cambrian Niutitang Formation in northern Guizhou Province, South China

Reservoir heterogeneity and fracture parameter determination using electrical image logs and petrophysical data (a case study, carbonate Asmari Formation, Zagros Basin, SW Iran)

Production Logging and its Implementation: A Technical Review

Contact Info

Product

Resources

About