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1993
4th Quarter
Technical Progress Report Geological and Petrophysical characterization of the Ferron Sandstone for 3-D simulation of a fluvial-deltaic reservoir(Contract No. DE-AC22-93BC14896)Submitted by Utah Geological Survey Salt Lake City, Utah 84109 January 25, 1994 Contract Date: September 29, 1993 Anticipated Completion Date: September 29, 1996 Government Award (fiscal year): $ 321,042 Program Manager: Thomas C. Chidsey, Jr. Principal Investigator: M. Lee Allison Contracting Officer's Representative Robert Lemmon U.S. Department of Energy Bartlesville Project Office P.O. Box 1398 Bartlesville, OK 74005 Reporting Period: September 29 - December 31, 1993 US/DOE Patent Clearance is not required prior to the publication of this document.
ObjectiveThe objective of this project is to develop a comprehensive, interdisciplinary, quantitative characterization of a fluvial-deltaic reservoir which will allow realistic inter-well and reservoir-scale modeling to be developed for improved oil-field development in similar reservoirs world-wide. The geological and petrophysical properties of the Cretaceous Ferron Sandstone in east-central Utah (figure 1) will be quantitatively determined. Both new and existing data will be integrated into a 3-D representation of spatial variations in porosity, storativity, and tensorial rock permeability at a scale appropriate for inter-well to regional-scale reservoir simulation. Results could improve reservoir management through proper infill and extension drilling strategies, reduce economic risks, increase recovery from existing oil fields, and provide more reliable reserve calculations. Transfer of the project results to the petroleum industry will be an integral component of the project.
Summary of Technical ProgressThe technical progress is divided into several sections corresponding to subtasks outlined in the Regional Stratigraphy Task of the original proposal. Other tasks are dependent on field work will begin in April, 1994. The primary objective of the Regional Stratigraphy Task is to provide a more detailed interpretation of the stratigraphy of the Ferron Sandstone outcrop belt from Last Chance Creek to Ferron Creek (figure 1). This regional study will include determining the dimensions of each sandstone body, depositional environment, and the nature of its contacts with adjacent rocks or flow units. The study will provide a basis for selecting optimal outcrops for detailed case studies of the major reservoir types (meander belt, mouth-bar complex, wave-dominated delta front, bar-finger sands, distributary channel, tidal channels). The morphological framework established from the case studies will be used to generate subsequent flow models.
Surface Mapping/Interpretation of the Outcrop BeltMost of the Ferron Sandstone outcrop belt within the study area (figure 1) will be obliquely photographed and photomosaics constructed. We are evaluating several techniques to determine the most cost-effective method for producing digital photomosaics without significant loss of resolution. Good quality air-photo coverage of the Muddy Creek area is currently available and the Utah Geological Survey (UGS) is negotiating a purchase or trade for this photography.
Collect and Interpret Existing Surface and Subsurface DataPublished and unpublished maps, measured sections, well logs, core descriptions, minipermeameter data, reports, and other data are being collected and compiled by the UGS. We have identified seven potential sources of basic geological and geophysical drill data on the Ferron Sandstone (table 1). The largest data holder is the Bureau of Land Management (BLM), which has hundreds of drill records from cola exploration holes drilled by Consolidation Coal Company (CONSOL). We checked lease records to determine which leases had been dropped by CONSOL and what drilling data could be released for use in our study. Land records show nine federal leases have been relinquished, three preference-right lease applications have been closed, and two prospecting permit applications have not been issued. Records show 352 wells with data on the unleased federal lands in the study area. The BLM has been contacted and permission to use these records has been obtained.We obtained data from two recently drilled core holes in the study area from the University of Utah Research Institute (UURI). BP Exploration (BP) has donated core and geophysical logs from five stratigraphic test holes in the study area. The UGS has compiled published records (Edson and Barnosky, 1977; Edson, 1978; Hodder and Jewell, 1979; Ellis, 1980; Ryer, 1981) from 39 wells drilled by the federal government (BLM and U.S. Geological Survey [USGS]) in the study area. These records include 14 wells with geophysical logs and 35 wells with core or cutting descriptions. The study area contains 58 oil and gas exploratory and development wells. We are obtaining records of the wells which penetrate the Ferron Sandstone. The UGS has developed a database for this study to integrate various geologic attributes of the Ferron Sandstone to point-source locations in the study area. The relational database application has been written and all of the tables, reports, and forms are ready for data entry. Both existing and newly collected data will be entered. The database will include well, core, and outcrop locations, lithology, porosity, mini-permeameter values, core plug permeability data, unit tops, as well as other information.
Potential Case-Study SitesThree potential case-study sites were delineated during a reconnaissance trip in October, 1993; Muddy Creek Canyon, Ivie Creek, and Willow Creek Wash in the north, central , and southern parts respectively of the study area (figure 1).Muddy Creek Canyon site -- Unlike the other potential study sites, where we will focus entirely on delta-front units in the basal part of the Ferron, the Muddy Creek site will involve analyses of the entire Ferron section. The nearly continuous outcrops, the 3-D aspect of the exposures, and the relative abundance of subsurface control facilitate 3-D mapping of individual reservoir types in the Ferron Sandstone in this area. Initial plans are to create a 3-D field-scale reservoir model of several sandstone units representing an area measuring about 3 miles (4.8 km) in the north-south direction, 2 miles (3.2 km) in the east-west direction, and 450 to 500 feet (140 to 150 m) vertically. The Ferron Sandstone is composed of seven deltaic units in the Muddy Creek Canyon area. Some of these units are stratigraphically simple; others include a variety of facies and display abrupt lateral facies variations. Ivie Creek site -- The Ivie Creek site was selected to examine the abrupt facies changes in the No. 1 delta-front unit in outcrops north of Ivie Creek, east of the mouth of Ivie Creek Canyon. The basal unit is a thick, sandy, river-dominated parasequence tentatively designated 1-Ivie-a which pinches out to the west. Overlying the 1-Ivie-a and extending beyond it to the west is a thin, presumable river-dominated, parasequence of very low-energy, tentatively designated 1-Ivie-b. Of particular interest is the interrelationship between high-angle foreset beds, hummocky, and planar laminated sandstones. Modeling will focus on the effects the various bounding surfaces would have on fluid flow in these units. We will recommend how bounding surfaces can be identified from core and well-log data and, ultimately, how such features should be considered in field development and secondary/enhanced recovery programs. Willow Springs Wash site -- The Willow Springs Wash site is the largest of the potential study areas. It covers an area 3.5 miles (5.6 km) long and 4 miles (6.4 km) wide (figure 1). The site was selected because of the excellent 3-D aspect of exposures in the Willow Springs Wash and Indian Canyon areas. The focus of our work at this site will be parasequences of the No. 1 delta-front unit (figure 2). Reservoir modeling will concentrate on variations in fluid flow between the parasequence types and on the amount of communication between each other.
ReferencesEdson, G.M., and Barnosky, C.L., 1977, Lithologic and geophysical logs of holes drilled in the Willow Springs quadrangle, Emery and Sevier Counties, Utah: U.S. Geological Survey Open-File Report 77-866, 31 p.Edson, G.M., 1978, Core drilling in 1978 - willow Springs quadrangle, Emery and Sevier counties, Utah: U.S. Geological Survey Open-File Report 78-1049, 21 p. Ellis, E.G., 1980, Geophysical logs and coal sections for four holes drilled in the Emery East quadrangle, Emery County, Utah: U.S. Geological Survey Open-File Report 80-1027, 5 p. Hodder, D.T., and Jewell, R.C., editor, 1979, Reclaimability analysis of the Emery coal field, Emery County, Utah: U.S. Bureau of Land Management EMRIA Report No. 16, 408 p. Ryer, T.A., 1981, The Muddy and Quitchupah projects - a progress report with descriptions of cores of the I, J, and C coal beds from the Emery coal field, central Utah: U.S. Geological Survey Open-File Report 81-460, 34 p.
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