Fetkovich documented that decline curve analysis that only applicable through the reduction period, when production reaches in boundarydominated flow. This, in fact, is a graphical method for visual matching or comparison of observational data using preplotted curves on a loglog diagram 8. Workflow for applying simple decline models to forecast. Production forecasting decline curve analysis petrowiki. Pdf decline curve analysis using type curves evaluation of. The constantpressureinfinite and finite reservcir solutions are placed on a common dimensionless curve with all the standard empirical expmential, hyperbolic, arid harmoni declinecurve. A normalized time has been developed that linearizes the rate decline vs. Using vogels method, draw the ipr curve, and estimate the wells potential. It is a semianalytical approach in that type curves are generated from analytical solutions of transient infinite radial systems at constant flowing pressure, while the boundarydominated flow period is defined using. Production data analysis future practices for analysis. Arps three types of decline and their formulas on a semilog plot after arps 1945. Decline curve analysis dca is a graphical procedure used for analyzing declining production rates and forecasting future performance of oil and gas wells. Over the past few years, several empirical models have emerged to. Decline curve analysis has been called the most commonly used and misused technique for forecasting future production and remaining reserves.
Spe 84287 decline curve analysis using type curves. Fetkovich used the curves with values of b between 0 and 1 hyperbolic and harmonic decline for matching solutiongasdrive depletion and gas reservoir depletion. The exponential decline rate used is arbitrary, and the value picked greatly affects the results of the forecast clark, 2011. Production declinecurve analysis is accepted for prediction of future performance of oil and gas wells and fields. Discussion and study guide spe 4629 decline curve analysis using type curves m. Because his method was rapid and easily applied, it was used extensively by ramsay in his evaluation of some 200 wells to determine the distribution of the decline curve exponent b. Fetkovich dca decline curve analysis course whitson academy. Black dots represent the outliers, whereas red dots are the oil rates included in the analysis. Case study of a lowpermeability volatile oil field using. Pdf a decline curve analysis was used for evaluating the well performance. Geological survey scientific investigations report 20175062, p. The analytic dimensionless terms for pressure, production rate, decline rate, and decline time were derived for saturated steam using the real gas potential and. Advanced production decline analysis and application 1st.
Permeabilitythickness determination from transient. Exponential decline appears to be a rare occurrence in nature, even though it is the most commonly used decline technique fetkovich theorydeveloped because traditional decline curve analysis is only applicable when well is in boundary dominated flowfetkovich used analytical flow equations to generate typecurves for transient flow, and. Fetkovich 2 developed type curve, marhaendrajana and blasingame 5 extended type curve method to a multiwell system, and li and horn 3 verified decline curve analysis dca method. Mathematics the arps decline curve analysis approach4 was proposed nearly sixty years ago. Oil and gas production rates decline as a function of time. Pdf analysing gas well production data using a simplified.
A decline curve analysis model based on fluid flow. Production decline analysis is a traditional means of identifying well production problems and predicting well performance and life based on real production data. Decline curve analysis three basic decline curve equations all of the equations give you the ability to predict cumulative production or production rate at some point in time. Spe spe 14237 case study of a lowpermeability volatile oil field using individualwell advanced decline curve analysis by m. Fetkovich established the typecurves that extended the arps type curves into the transient flow region 3,4. In the early 1980s, fetkovich introduced an analysis of decline curve using type curves. Jun 19, 2015 for the love of physics walter lewin may 16, 2011 duration.
Reserve estimation using decline curve analysis for boundary. Exponential decline appears to be a rare occurrence in nature, even though it is the most commonly used decline technique fetkovich theorydeveloped because traditional decline curve analysis is only applicable when well is in boundary dominated flow fetkovich used analytical flow equations to generate typecurves for transient flow, and. Pdf decline curve analysis using type curves evaluation. Gas reservoir declinecurve analysis using type curves. These rate integral and rate integral derivative typecurves aid in obtaining a more unique match. Basic concepts in decline curve analysis by mike fetkovich table of contents tape 1 click here to watch the entire fetkovich course from beginning to end of tape 1. A decline curve analysis model based on fluid flow mechanisms. Gas reservoir declinecurve analysis using type curves with. Fetkovichs decline curve dimensionless variables are defined as below12. The socalled blasingame plot palacio and blasingame 1993 and doublet, et al 1994 is a replot of the traditional fetkovich plot fetkovich 1980, with provisions for a variable rate and pressure histories as opposed to the. Blasingames improvements on the fetkovich style of production decline analysis are further enhanced by the introduction of two additional typecurves which are plotted concurrently with the normalized rate typecurve. On a larger perspective, it aids as a means of identifying well production problems. The left part when t dd decline rate curve shifts downwards with the increased r ed, and the right part when t dd 0. Historymatching and forecasting of three unconventional.
Decline curve analysis is the most currently method used available and sufficient 1. Production declinecurve analyses are the most widely used tool in the industry for oil and gas reservoir production analyses. Decline curve analysis three basic decline curve equations all of the equations give you the ability to predict cumulative production or. Pdf analyzing well production data using combinedtype. Equation, decline curve and type curve technique, of which decline curve analysis numbers among the earliest methods and yet the conventional tool most practically applied. Production decline curve analyses are the most widely used tool in the industry for oil and gas reservoir production analyses. It uses empirical decline models that have little fundamental justifications. Data points lying outside the type curve represent transient flow. The use of the fetkovichmccray type curve format i.
Prediction of reservoir performance applying decline curve analysis. Advanced production decline analysis and application starts from the basic concept of advanced production decline analysis, and thoroughly discusses several decline methods, such as arps, fetkovich, blasingame, agarwalgardner, npi, transient, long linear flow, and fmb. One type of clinecurve analysis involves the hyperbolicdeclinecurve equation. The constantpressureinfinite and finite reservcir solutions are placed on a common dimensionless curve with all the standard empirical expmential, hyperbolic, arid harmoni declinecurve equations. Historymatching and forecasting of three unconventional oil. Most decline curve methods have two main limitations.
This course will give the learner a better understanding of how fundamental reservoir properties and drive mechanisms affect the shape of the production decline curve and how to avoid many of the mistakes commonly found in. Fetkovich decline curve analysis excel calculations. Comparison of empirical decline curve analysis for shale wells a thesis. In many cases, the results of this model closely match those determined using the van everdingenhurst approach. Brons 1963 and fetkovitch 1983 applied constant pressure solution to diffusivity equation and demonstrated that. Matching and extrapolating these curves is equivalent to using the harmonic and hyperbolic declines with the usual semilog decline curves. The production data analysis methods started long ago when a decline trend was used as a tool for economic evaluation. A practical systematic introduction to each method helps the reservoir. Pdf decline curve analysis using type curves semantic scholar. If your connection is slower, you will want to download the files separately.
To understand the effects of main parameters on rate transient behaviors of a hwms, we develop the blasingame compound type curves to perform the sensitivity analysis through the rda model proposed in this paper i. This book will serve as an authoritative reference on modern production declinecurve analyses, including details of some recent advances in the technology. For boundarydominated flow, fetkovich showed the arps family of curves with b as a parameter. An approach to modeling production decline in unconventional. Fetkovich recognized that decline curve analysis was only applicable during the depletion period ie.
Truncating a hyperbolic decline with an exponential decline solves some of the problems associated with decline curve analysis, but it is not an ideal solution. Types of decline analysis in production forecasting petrowiki. Estimate what the wells potential rate will be when the static pressure dropped to 1500 psig. Fetkovich published 2002 ratetime decline curve extrapolation is one of the oldest and most often used tools of the petroleum engineer. Basic concepts in decline curve analysis fetkovich tapes table.
Agarwal and gardner have compiled and presented decline type curves for analysing. The b0 case is for exponential decline of a liquid reservoir. If you have a fairly fast connection, you may wish to download the entire package. Decline type curve analysis fetkovichmccray format. Decline curve analysis is an empirical procedure that predicts the decline in production rates of gas and oil wells. Spe 4629 decline curve analysis using type curves semantic. Discussion and study guide spe 4629 decline curve analysis using. Production decline data from different types of waterdrive reservoirs were analyzed as examples of using the new decline analysis model. Types of decline analysis in production forecasting.
Its output the estimation of remaining reserves is completely dependent. Modified fetkovich type curve which includes transient linear b 2 and. Fetkovich dca decline curve analysis course youtube. The fetkovich production decline curve analysis method was extended for application to vapordominated geothermal reservoirs for the purpose of estimating the permeabilitythickness product kh from the transient production response. This study compares four recently developed decline curve methods and the traditional arps or fetkovich approach. We would like to clarify that our study and the discussions in this article are limited to twophase fluid flow. Spe 84287 decline curve analysis using type curves fractured.
Decline curve analysis for estimating eurs and ooips. Advanced production decline analysis and application. Jahediesfanjani, hossein, 2017, application of decline curve analysis to estimate recovery factors for carbon dioxide enhanced oil recovery, chap. A loglog plot with combined radial and bdf declines for various reservoir boundaries. Assessment of reservoir performance of a well in south. Fetkovich 2 developed type curve, marhaendrajana and. The analytic dimensionless terms for pressure, production rate, decline rate, and decline time were derived. Multiwell decline curve analysis shows the validity of the variables s skin, k, ooip, ultimate fractional recovery and gor versus fractional recovery evaluated from each wells type curve match point. Aug 22, 2017 most decline curve methods have two main limitations. Over the past few years, several empirical models have emerged to address the second limitation, but they.
This book will serve as an authoritative reference on modern production decline curve analyses, including details of some recent advances in the technology. Arps in 1945 presented the classical decline curve analysis dca technique which is based on pure empirical. Fetkovich 1968 improved on earlier work by arps in predicting. Pdf decline curve analysis using type curves semantic. This paper presents rigorous methods to analyze and interpret exponential,hyperbolic. A curve fit of past production performance is done using certain standard curves. Analysing gas well production data using a simplified decline curve analysis method. Arps type curves could only be used to analyze the data in the period of boundarydominated flow. Decline type curve analysis fetkovich mccray format.
Most of the existing decline curve analysis techniques are based on the empirical arps equations4. Application of decline curve analysis to estimate recovery. This excel spreadsheet plots fetkovich decline curves for gas wells. This faper shows that the declinecurve analysis approah does have a solid fundamental basis. Prediction of reservoir performance applying decline curve.
Rate decline analysis for horizontal wells with multiple. These variables must all give consistent and reasonable numbers when compared with each other. The most popular decline curve is that which represent the decline in the oil or gas. Fetkovich 1971 developed a method of describing the approximate water influx behavior of a finite aquifer for radial and linear geometries. Analysis methods traditional background for traditional analysis decline curve analysis is a graphical procedure used for analyzing declining production rates and forecasting future performance of oil and gas wells. Pdf verification of decline curve analysis models for.
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