The product will save significant man hours over traditional decline curve analysis software. Initial flowrate in the context of the exponential decline curve analysis, this is the flowrate essentially on the first day of production, although the average flowrate for the first full month could also be used. Cumulative production semilogarithmic axes straight line trends on this plot results in highly optimistic reserves 3p. 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. Your manager asks you to perform decline curve analysis for a shale well in permian basin wolfcamp reservoir. Thereafter, production will decline at the exponential rate. Spe textbook series, volume 9, society of petroleum engineers. Depletion and decline curve analysis in crude oil production. Decline curve analysis in east almabrouk field case.
Decline curve analysis for estimating eurs and ooips. Conventional decline curve analysis should be used only when mechanical conditions and reservoir drainage remain constant and the well is producing at capacity 197. Depletion rate also can be connected to decline curves. Mead9 noted in his discussion of b factor decline curve exponent that.
Includes exponential, hyperbolic, harmonic, and hyperbolictoexponential models as well as the preceding with initial curtailment or a period of linear rate buildup. The traditional decline analysis can also be modified to a terminal limiting decline rate. Quick decline is the ultimate production oil and gas decline analysis and economic evaluation tool for everyone. Decline curve analysis dca is a graphical procedure used for analyzing declining production rates and forecasting future performance of oil and gas wells. In advanced production decline analysis and application, 2015. The remaining reserve calculation becomes more reliable whenever data points are well screening. The nominal decline factor d is defined as the negative slope of the curve.
The harmonic decline is the special case of equation 1 when the b exponent equals one. Production decline curve analyses are the most widely used tool in the industry for oil and gas reservoir production analyses. A b factor is a hyperbolic exponent used in the arps decline curve equation to model either hyperbolic or exponential production decline, depending on the reservoir and production characteristics. Study on the decline analysis of oil well stimulation rule. Decline curve analysis is the most currently method used available and sufficient 1. Phdwin is a fullfeatured economic and decline curve analysis program. The effective decline factor d is a stepwise function that is in better agreement with data recording practices. Case study of a lowpermeability volatile oil field using individualwell advanced decline curve analysis. The decline curve analysis template for tibco spotfire allows you to quickly plot oil forecast curves on top of your actual production, using the arps hyperbolic equation. 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. The b factor regulates the initial steepness of the decline curve. Phdwin offers evaluators a tool that combines an intuitive interface with sophisticated functionality.
When using the decline curve feature, view the computer generated autopick as a guiding start. Determine the amount of prior production and add that to the partial eur for the actual estimated ultimate recovery. The production forecasting guidelines will address the following types of decline analysis. Your manager asks you to perform decline curve ana. The empirical arps decline equation isused to represent the relationship. Decline curve analysis help exponential decline curve analysis new features display on chart allows the user to display the decline line on the chart itself decline curve start date when you want the decline curve to be displayed on the chart initial flowrate in the context of the exponential decline curve analysis, this is the flowrate essentially on the first day of production.
Functions included for computing rate, cumulative production. Hyperbolic decline curves have been used in many cases, particularly in the late history of pressure supported production. Decline curve analysis in east almabrouk fieldcase study alfitouri ibrahim jellah abstract. The plots can also help you choose which b factor is most appropriate for your well.
Pdf verification of decline curve analysis models for. A practical systematic introduction to each method helps the reservoir. Arnold and anderson 1908 presented the first mathematical model of dca. Decline curve start date when you want the decline curve to be displayed on the chart. The case of eagle ford linnea lund production of oil and gas from shale is often described as a revolution to energy production in north america. Decline curve analysis free decline curve analysis software. He only indicated that exponential decline b0 is most common and that the coefficient b generally ranges from 0 to 0. Quick decline production oil and gas decline analysis. Advanced production decline analysis and application 1st. Decline exponential decline rate calculation this routine presumes that recoverable reserves are known from some other source, such as volumetric analysis from log data, decline curve analysis, or material balance calculations. Production decline analysis is the analysis of the past trends of declining production performance, that.
Production rates decline as a function of time owing to loss of reservoir pressure and changing relative volumes of the produced fluids. The decline curve shows how oil and gas production rates decrease over time. The nominal or instantaneous decline rate, r, of the skin factor, s. Arps decline curve analysis in r functions for arps declinecurve analysis on oil and gas data. The beginners guide to drillinginfos production charting. This book considers the advanced production decline analysis by. Petroleum engineers, landmen, royalty owners, prospectors, and everyone in between can easily use quick decline to get a leg up on the competition. This book will serve as an authoritative reference on modern production decline curve analyses, including details of some recent advances in the technology. Cutler 1924 also used the loglog paper to obtain a straight line for hyperbolic decline, so the curve shifted horizontally. For exponential decline it is a constant with time.
An advanced approach for decline curve analysis, which is applicable for changes in pressure or drainage, has been presented by fetkovich 267, 268. The hyperbolic curve requires estimation of both di and the exponent b. Life cycle reserves appraisal using an integrated workflow process for tight gas sands. Declinecurveanalysis models are used frequently but still have many limitations. Aug 04, 2015 the arps decline curve analysis approach was proposed nearly60 years ago. The most popular decline curve is that which represent the decline in the oil or gas. Production forecasting decline curve analysis petrowiki. Abstract advanced decline curve analysis course this oneday course will show how loglog type curve analysis can be performed on declining production rate data completely analogous to the loglog type curve matching procedure presently being employed with. Prediction of reservoir performance applying decline curve analysis.
Prediction of reservoir performance applying decline curve. Finally, the cumulative recovery should result in a reasonable recovery factor, based on volumetrics. The trouble in applying decline curve techniques for shale oil wells is the lack of production history. Decline curve analysis models are frequently used but still have many limitations.
Decline curve analysis1 petroleum reservoir exponentiation. Production decline curve analysis is a traditional means of identifying well production problems and predicting well performance and life based on measured oil well production. To assess the accuracy of decline curve analysis, or any forecasting technique, it is helpful to compare a hindcast to actual production history. This program is provided by gotech as is and gotech does not fully support this program. Traditional decline generates a forecast of future production rates based on the equations defined by arps. L337tech llc also offers paid training for quickdecline. Oil, gas and water saturation levels are important factors and refer to the.
Quick decline production oil and gas decline analysis and. In this study decline analysis was applied for wells, and whole field. It uses empirical decline models that have little fundamental justifications. Historically, decline curve models were derived based on observations of production, loss ratios, and bfactors. Fetkovich hydraulically fractured well type curve analysis can be added to improve confidence in.
The production decline curves have two main functions, including a to determine the reservoir permeability parameter by matching the production decline curve with it, which belongs to quantitative analysis, and b to diagnose the production performance characteristics, that is, to qualitatively judge the. Conversely, predictions from the decline history assumes that no significant changes in these factors will take place. Decline curve analysis free decline curve analysis. Nominal decline is a continuous function and it is the decline factor that is used in the various mathematical equations relating to decline curve analysis. Thus, a major advantage of this decline trend analysis is inclusion of all production and operating conditions that would influence the performance of the well. Pdf hyperbolic decline parameter identification using. The decline type of well 1 is exponential, and the remaining reserve calculated. We also found that application of pressurecorrected rates in decline curve analysis dca may substantially improve the interpretation of data from unconventional oil wells flowing under unstable operating conditions. Production decline analysis is a traditional means of identifying well production problems and predicting well performance and life based on real production data. A decline curve analysis model based on fluid flow.
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. Cutler 1924 also used the loglog paper to obtain a straight line. Set r in the equations below to equal roil or rgas. Approaches of declinecurve analysis used for naturally fractured reservoirs developed by waterflooding have been. The fullsize fetkovich typecurves can be ordered from the book order department of spe. While my work does not account for the complex differences among various shale oil plays due to. Dca parameters are easily input to fit your data and forecast production on the fly. However, most curve analysis is done by computers, promoting a blackbox approach to engineering and leaving engineers with little understanding of the fundamentals of decline analysis. Analysis of production decline curves spe book store.
Another way of representing the decline rate is based on rate q and the decline exponent constant b. There are two types of decline factors often called the decline rate. Calculate ooip using 35% recovery factor if the reservoir has undergone tertiary recovery. The equation shows that the respective decline curves are generated based on the value of b.
Approaches of decline curve analysis used for naturallyfractured reservoirs developed by water flooding have been few. The arps declinecurveanalysis approach was proposed nearly60 years ago. Depending on the well history and type, adjusting the b factor or nominal decline rate sometimes obtains the best data fit. Types of decline analysis in production forecasting petrowiki. The full size fetkovich typecurves can be ordered from the book order department of spe. Types of decline analysis in production forecasting. A decline curve analysis model based on fluid flow mechanisms. The theory of all decline curve analysis begins with the concept of the nominal instantaneous decline rate a, which is defined as the fractional change in rate per unit time.
A method for estimating reserves and predicting production in oil reservoirs and oil fields. Besides, the plotting and analysis of apda curves with blasingame. Decline curve analysis in unconventional reservoirs using a. Case study of a lowpermeability volatile oil field using. Decline curve analysis is a long established tool for developing future outlooks for oil production from an individual well or an entire oilfield. The conventional analysis of production decline curves for oil or gas production. Drillnomics takes a visually fit curve and calculates the production from that curve. With inputs for multiple scenarios, running sensitivities on the dca inputs is fast and easy. Production decline curve an overview sciencedirect topics. Decline curve analysis is on of the oldest and one of the most. Before the availability of computers, decline curve analysis was performed by hand on semilog.
Apr 12, 2019 in the equation below, qi initial production rate, qt the production rate at the given time, t time, diinitial decline fraction, b hyperbolic exponent from 0 to 1. Pro duction prediction based on reservoir simulator. Crains petrophysical handbook reserves from decline curve. Advanced production decline analysis and application. Decline curve analysis dca is used to predict the future production of oil and. Apr 16, 2015 this feature is not available right now. In the equation below, qi initial production rate, qt the production rate at the given time, t time, diinitial decline fraction, b hyperbolic exponent from 0 to 1. Please try to fit the given production data in the spreadsheet, and report whats your b factor and estimated ultimate recovery. Quick decline allows for easy production and well data imports for most of todays modern tools. Many published papers have tried to interpret the arps declineequation theoretically 67.
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. Spe member price usd 70 new check out the latest book from this author team analysis of oil and gas production performance long ago, engineers recognized the characteristic decline of oil and gas well performance and attempted to predict its course by fitting equations to the production history. Since the beginning of this century the shale oil production has increased from practically zero to currently supply almost half of the u. However, a great number of studies on production decline analysis are still based on this empirical method. Decline curve analysis dca is used to predict the future production of oil and gas, and it has been widely used since 1945. But, if the production data is very noisy, the computer may pick a very low or high 3. Please direct your comments and questions to the author, dr. Lewis 1918 production decline curve analysis is important in determining the value in oil and gas wells in oil and gas economics. Decline analysis curve an overview sciencedirect topics. Oil and gas decline curves rock river minerals, lp. Decline curve analysis is a long established tool for developing future outlooks for oil production from an. A new theory for interpreting rate decline trends in.