Shaly sand reservoirs impact on porosity and water. The thomas stieber crossplot is a common method used with gamma ray and porosity data to determine shale distribution. Ashish mathur petrophysics lab scientist wdvgl petroleum. Developments in petroleum science volume 62 practical petrophysics series editor john cubitt holt, wales developments in petroleum science volume 62 practical petrophysics martin kennedy msk scientific consulting, pty ltd perth, australia amsterdam boston heidelberg london new york oxford paris san diego san francisco singapore sydney tokyo elsevier. Thomas stieber model shows that shale distribution in sands of the. True, the solution proved to be insightful and novel, but more importantly, it was. The thomas stieber approach is often regarded as the most suitable for a binary sandshale system and if conditional assumptions are met, results in a linear trend from which nettogross can be calculated. Journal of petroleum and gas engineering analysis of shaly. Crains petrophysical handbook chapter and topic index. Thomas and stieber demonstrate the necessity to handle the effects of anisotropy on the determination of porosity. Pickett, hingle, sprwa, thomas stieber, zplots, pressure vs depth plots and many other crossplots. Full deterministic analysis including most vshale, porosity, and water saturation equations. This generalized stieber equation, reduces exactly to the regular stieber equation when c3, replicates exactly igr when c1, and yields vsh0 as c if c.
Shales in the reservoir causes complications for the petrophysicist because they generally are. He has authored or coauthored two books on applied and practical petrophysics plus numerous papers on the topic. A petrophysics model includes the theoretical and experimental correlations among various sets of petrophysical properties. Thomas stieber model shows that shale distribution in sands of the eastern niger delta basin is mainly structural with few of disperse and laminar ones. However, because the shale can be distributed through the sand in different ways, such as laminated, dispersed.
Application of integrated clustering and petrophysical. First, we investigate the thomas stieber model, a model commonly used for. Mitchell, editor iii facilities and construction engineering kenneth e. Shaly sand interpretation using cecdependent petrophysical. Core data handled on true core depths, not interpolated to wireline depths. Ntg, sand porosity, sw using thomas stieber approach tbp permeability transform saturation height function using tbp permeability transform as input advanced logging.
Nuclear magnetic resonance nmr measurements tool theory, t2 principles and measurements porosity, saturation and permeability from nmr measurements. Most often there are thicker beds small channels, bars, lobes mixed. Micro and macroscopicanisotropic reservoir characterization has, recently, been dealt with by two main approaches, 1 applying the thomas stieber technique on uniaxial resistivity, or 2 applying the tensor model technique using multicomponent induction measurements. A free powerpoint ppt presentation displayed as a flash slide show on id. Ccolorado school of minesolorado school of mines sspring. Despite the dominance of laminated shale, the reservoir quality from porosities 26. Electrical anisotropy analysis by a modified thomasstieber. His academic teaching experiences have been in the areas of petrology, petrophysics, and environmental geology. Thomas and stieber has a new approach to determine the clay type as shown in figure 2. From the vertical and horizontal resistivity, an electrical anisotropy template was built in conjunction with the modified thomas stieber model and core observations. Data from a suite of well logs were used to estimate the effect of reservoir shaliness on petrophysical parameters of some reservoir rocks of the eastern niger delta basin. Integrating sequence stratigraphy and rockphysics to. Dec, 2019 thomas stieber crossplot of gamma ray and total porosity using zones mean property clean sand point is 46.
Vertical and horizontal resistivity analysis by an. Probabilistic modeling option for complex lithology scenarios. Crains petrophysical handbook publications by ross crain. Typically, 1d highresolution data is acquired to estimate sand volume fraction, porosity, and permeability, and 3d fluids data is used to evaluate the hydrocarbon type and content in the thin sands. First, we investigate the thomas stieber model, a model commonly used for estimating volume fraction of sand and its porosity in thinly bedded sandshale sequences. Thomasstieber method was used to determine the shale distribution in the reservoirs and its properties. Discrimination of saturation and pressure changes from changes in. The book the art of being a scientist, coauthored by roel snieder and ken larner is now available from cambridge university press. Porositypermeability crossplot interpretation from quantile curves. Shale can be distributed through a shaly sand in different ways, such as laminated, dispersed, structural, or a combination of these.
You can design your own petrophysical workflow to generate meaningful quicklook interpretations based on local expertise and the application of industry standard. The society of petrophysicists and well log analysts. This discrimination using a thomas stieber analysis, allows for improved estimation of saturations and identifying locations of bypassed pay. Thomasstieber model shows that shale distribution in san. Thomas stieber thin bed analysis resource potential 300 mm bblrisked behind pipe green. Limited vertical resolution of logging tools causes shoulderbed effects on borehole measurements, therefore biases in the assessment of porosity and hydrocarbon saturation across thinlybedded rock formations. Results indicate that the classified rock types and their petrophysical ranking. This figure is a geometrical solution of the thomas stieber method for laminated sands and.
Adding a third component, such as silt, violates the assumptions and distorts this trend into a nonlinear boomerang shape. Petrophysical evaluation of thinly bedded formations requires accurate estimation of laminar and dispersed shale concentration. Analysis of shaly sand reservoir rocks in the eastern niger. The distribution of shale in sandstones and its effect. Elastic wave anisotropy and shale distribution petrophysics. Density and photoelectric logs measurement concept and. The volume of the shale is the most critical parameter, and controls the porosity and saturation calculcation. Linking petrophysics courses include n187 low resistivity low contrast pay, us only, n267 petrophysics for shale gas, us only and the field course n030 rocks and fluids.
We present sensitivity and uncertainty analyses of this model under various scenarios, especially when the model assumptions are violated. Shales in the reservoir causes complications for the petrophysicist. Thomas stieber model among other models the distribution of shale in sandstones and its effect upon porosity, e. Advanced well log interpretation training course mobility. At present only the northern of the field is developed, with 7 platforms and 54 producing wells, of which 20 are horizontal. Reservoir rock, shaly sands, petrophysical parameters, well logs, models. Spe 109848 formation evaluation in thin sandshale laminations. Thomasstieber model for thinbedded shalysand reservoirs wed oct 19, 2011 6. Clay minerals in fluvial shaly sandstone of upper triassic. The problem with silt in lowresistivity lowcontrast. Bima field, offshore northwest java, is a sizeable reservoir containing reserves of approximately 700 mm bbls ooip with a 50 bcf gas cap.
The thomas stieber model posits that shale in reservoir rocks can be. In this study, we incorporate a depthdependent thomas stieber model to describe the shale laminations and use core observation to describe the existence of shale anisotropy. Petrophysics model the geological model described above is used to populate the petrophysicalproperties, assuming ameaningfulpetrophysics model. Journal of petroleum and gas engineering analysis of. Thomas stieber model for thinbedded shalysand reservoirs i am working on a project which is related to thomas stieber approach for sandshale sequence to determine netgross and porosity but i am not able to get any good literature on this for reference. This article is part of a series of short tutoriallike notes styled to mentor users of digital well logs in becoming confident practitioners of petrophysics at the close of shalysand tutorial part 2, i implied, or sortof promised that this final part would provide some guidance or at least guidelines on the application of my favorite models equations, transforms. This allows netpay cutoffs to be applied based on sand volume, porosity, and water saturation. The log section was digitized using neuralog software. To our knowledge, there is no equivalent method based on formation anisotropy measurements. Previously, we developed a combined inversion procedure for induction resistivity and density logs to improve the petrophysical assessment of multilayer reservoirs. The ef knowledge was combined with petrophysics, rock fabric number rfn and application of microscopic studies comprising thin sections ts, scanning electron microscopy sem, back scattered electron bse and energy dispersive xray spectroscopy eds on fauna acquired from novel drill cuttings of selected wells. Quantitative assessment of resistivity anisotropy in evaluation of. In this paper laminated shaly sand layers lss are studied by using thomas stieber model and conventional petrophysical logs. Thomas stieber crossplot for the clay type in the gas sand reservoir by well log porosity.
Edger forum, the jackson school of geosciences, ut. Jlog petrophysical software petrophysics software formation. The thomas steiber shalysand model analysis revealed that laminated shale was widely distributed all through the devo field reservoirs. Identifications of flood fronts, preferential pathways, thief zones, and flow barriers, i. Results and interpretation the results from interactive petrophysics were exported as input into the microsoft excel sheet, and various plots e e. The sand layer porosity phisand determined from thomas steiber method deserves comments. Nov 12, 2018 thomas and stieber original model modified from middle crossplot and application model for tags sandstones in well14 and well15 left and right crossplots based on available data from only two wells well14 and well15, fig. Thomas stieber model for thinbedded shalysand reservoirs wed oct 19, 2011 6. While the aapg geoscience director, he led a tenfold increase in titles published including digital and book releases. Thomas stieber model was applied to the desired layer by laminated shaly sand analysis module in geolog 7.
Top 10 landmark papers in petrophysics and formation. Requires knowledge of gamma ray and density log response to pure shale and clean sand end points thomas stieber plot 0. The integration of geology, geophysics, petrophysics and. The key to shaly sand evaluation using the waxmansmits equation in the absence of core data. Practical petrophysics by elsevier science ebook scribd. Crain s petrophysical handbook chapter and topic index. Dec 01, 2019 the thomas stieber diagram thomas and stieber, 1977 is a widely applied petrophysical method for determining whether shale distributions in siliciclastic reservoirs are laminated, dispersed, or structural xu et al. If you can, try to use the triaxial resistivity where you can resolve the horizontal resistivity rh and vertical resistivity rv. The thomas stieber model can be applied, in conjunction with an approximation of total porosity, to compute the sand total and effective porosity. Vertical and horizontal resistivity analysis by an electrical. Thinly bedded pay in clastic reservoirs, recognition. Shales in the reservoir causes complications for the petrophysicist because they generally are conductive and mask the high resistance characteristic of hydrocarbons.
Thomas stieber crossplot analysis to evaluate lamination volume and true resistivity of sand laminae. Crains petrophysical handbook downloads spreadsheets. Skilled petrophysical methods orconventonalresrvoirs. Authors may republish the article as part of a book or other. Clean formation structural shale porosity porosity matrix matrix porosity matrix porosity shale shale matrix porosity matrix laminar. To predict the reservoir performance it is essential to understand the nature of the shale distribution in the reservoir. Evaluation of laminated shaly sand sequences in ahwaz oil. Hundreds of students at csm have taken this course taught by roel, and their feedback consistently indicates how useful the material in this book has been to them. Improved workflow for evaluation of thinly bedded sandstones. The thomasstieber diagram1 is used to determine the distribution of shale within a shaly sand formation by comparing the total volume of shale with the total porosity. Multicomponent induction resistivity logs allow differentiation of horizontal and vertical resistivity. A shale volume parameter derived from the response of the gamma ray log in shaly sands is often used to correct the responses of other logs for the effects of the shale.
Quick links to all downloads and spreadsheet software for petrophysical analysis. Iso terms, where the log quality control lqc books sort of promised. Stieber, 1975, the distribution of shale in sandstones and its effect upon porosity. Volume shale, porosity, and water saturation are the basic parameters to estimate sand layer resources. Ppt interactive petrophysics what powerpoint presentation. The two plots suggest a clean sand porosity phisand of 0.
Thomas stieber crossplot methods, multicomponent induction tools and resistivity anisotropy. Stieber, spwla sixteenth annual logging symposium, june 47, 1975. Petrophysics the techlog platform enables you to perform both basic and advanced interpretation on all wellbore data types, including log, core, images, photos, and thin sections. The correlation of a gamma ray parameter to shale volume is usually presented as one direct relationship. Permeability and rock typing porositypermeability crossplot interpretation from quantile curves. Porosity, saturation and permeability from nmr measurements. Petrophysics and fracture optimization a 20step workflow. Project management through all phases of engineering estimates, design, and. Reservoir quality, nettogross, and fluid identification in. Journal of petroleum and gas engineering academic journals. The thomas stieber diagram1 is used to determine the distribution of shale within a shaly sand formation by comparing the total volume of shale with the total porosity. Transactions of the spwla 16th annual logging, symposium, june 47, 1975.
Clean formation structural shale porosity porosity matrix matrix porosity matrix porosity shale shale matrix porosity matrix laminar shale. Petrophysical interpretation in shaly sand formation of a gas. Our new crystalgraphics chart and diagram slides for powerpoint is a collection of over impressively designed datadriven chart and editable diagram s guaranteed to impress any audience. Petroelectric modeling for csem reservoir characterization. Improved petrophysical evaluation of a thinly bedded. Purchase practical petrophysics, volume 62 1st edition. Top 10 landmark papers in petrophysics and formation evaluation. In the fluvial heterolithic sequences the traditional petrophysical model.
However the thomasstieber requires a large number of parameters. Laboratorymeasured reservoir core plug porosities range 2031% and permeability varies between and 4500md. Clayey sand aka shaly sand, thomasstieber laminated sandshale. Coring and core analysis training course petroskills cca. Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects.
The data points markers with labels from a to k alongside them represent the zones. Paper t, transactions, spwla 16th annual logging symposium, new orleans, louisiana, 47 june. Try using thomas stieber method was used to determine the shale distribution in the reservoirs and its properties. Thomas hess and steffen saustrup for helping with paradigm focus mark wiederspahn, kevin johnson, and john gerboc for technical support technical support staffs in cggveritas hampsonrussell, iongtx gmg, paradigm focus, fugro jason jgw, and schlumberger eclipse. The course is intended for engineers and geoscientists and technical assistants needing to understand better, the principles of log interpretation andor to update themselves on the range of log measurements and techniques now available to them, and to appreciate the complexities of interpretation in more complex reservoirs. Petrophysical evaluation of thin beds low resistivity and low contrast pays using thomas stieber method. The techlog platform enables you to perform both basic and advanced interpretation on all wellbore data types, including log, core, images, photos, and thin sections. Petrophysical characterization using well log resistivity and. Pdf analysis of shaly sand reservoir rocks in the eastern niger. However, shallow depth of investigation, slow logging speed. Practical petrophysics looks at both the principles and practice of. The proposed technique helps in selecting maximum sand and shale porosities as one of the essential parameters in the thomas stieber model for typifying and quantifying the shale and for deciding. The problem with silt in lowresistivity lowcontrast lrlc. The model is required to be validated using available well log and core data.
948 1597 1733 740 1876 163 691 1 1609 1522 1018 620 957 591 1334 1001 1441 549 52 1326 863 1764