Creating 3-D Reservoir Models Using Areal Geostatistical Techniques Combined with Vertical Well Data (1995)

Creating 3-D Reservoir Models Using Areal Geostatistical Techniques Combined with Vertical Well Data Sheldon B. Gorell Sheldon B. Gorell Western Atlas Software Search for other works by this author on: This Site Google Scholar Paper presented at the SPE Western Regional Meeting, Bakersfield, California, March 1995. Paper Number: SPE-29670-MS https://doi.org/10.2118/29670-MS Published: March 08 1995 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Gorell, Sheldon B. "Creating 3-D Reservoir Models Using Areal Geostatistical Techniques Combined with Vertical Well Data." Paper presented at the SPE Western Regional Meeting, Bakersfield, California, March 1995. doi: https://doi.org/10.2118/29670-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE Western Regional Meeting Search Advanced Search SPE MemberAbstractAdvances in geostatistics, seismic processing and interpretation are now providing capabilities for improved reservoir characterization by allowing integration of seismic and well data. In certain situations where correlations can be established between seismic and well attributes, the seismic data can be used to bias the interpolation of well attributes away from the wells using techniques such as cokriging (or variants thereof). Traditionally, this approach has been applied in situations where areal seismic attributes over a reservoir interval are correlated with zone-averaged petrophysical attributes. These techniques result in improved zone-averaged petrophysical maps. However, for certain applications, particularly dynamic reservoir simulation of fluid flow, zone-averaged properties may be inappropriate. In such situations, it is necessary to somehow "unaverage" the zone-averaged maps to produce vertically heterogeneous maps. Since the scales of seismic resolution are still generally much coarser than those needed for simulation models, seismic data often does not provide much, if any, information which can be used to infer details about internal reservoir heterogeneities. This paper discusses a technique for creating 3-D reservoir models based on underlying seismic maps and some measures of vertical heterogeneities at the wells. What results are 3-D reservoir models which honor both the vertical variations at the well locations and the geostatistically created zone-average petrophysical maps. Some examples are presented which demonstrate the applicability and limitations of this technique. In addition to visual inspection of the models, reservoir injection and production is simulated and used to illustrate the importance of various modeling assumptions.IntroductionImproved characterization of reservoir heterogeneities has long been recognized as necessary for better predictions of reservoir performance. Advances in geostatistics, seismic processing and interpretation are now providing capabilities for integration of seismic and well data. Once an interval within a reservoir has been identified, and tied to a 3-D seismic volume, different seismic attributes such as velocity, amplitude, frequency, and energy can be extracted and analyzed. If a relationship can be established between values of petrophysical attributes and one or more seismic attributes at known well locations, then geostatistical algorithms, such as co-kriging, can be used to create improved petrophysical models. A complication arises because the scale of seismic resolution is usually orders of magnitudes larger than those available from well data. For example, well logs can typically provide resolution at less than one foot spacing, while resolution within a seismic loop is typically hundreds of feet.P. 547 Keywords: well location, correlation, geological modeling, upstream oil & gas, porosity, spe 29670, well data, procedure, heterogeneity, interpretation Subjects: Reservoir Characterization, Geologic modeling, Seismic processing and interpretation This content is only available via PDF. 1995. Society of Petroleum Engineers You can access this article if you purchase or spend a download.