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Characteristics of Discrete and Basin-Centered Parts of the Lower Silurian Regional Oil and Gas Accumulation

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Characteristics of Discrete and Basin-Centered Parts of the Lower Silurian Regional Oil and Gas Accumulation U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Characteristics of discrete and basin-centered parts of the Lower Silurian regional oil and gas accumulation, Appalachian basin: Preliminary results from a data set of 25 oil and gas fields Robert T. Ryder 1 Open-File Report 98-216 This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards and stratigraphic nomenclature. Any use of trade names is for descriptive purposes only and does not imply endorsement by the USGS. 1 U.S. Geological Survey, Reston, Virginia 20192 CONTENTS Page Abstract....................................................................................... 1 Introduction.................................................................................. 2 Availability of relevant oil and gas field data............................................. 6 Comparison of selected oil and gas field characteristics................................. 6 Depth to production and hydrocarbon types..................................... 6 Structural setting and natural fractures........................................... 10 Trap types............................................................................ 12 Reservoir porosity and permeability............................................. 15 Reservoir water saturation and volume and composition of produced waters............................................................ 18 Segregation of gas and fluids in reservoirs....................................... 22 Reservoir pressure and bottom-hole temperature............................... 23 Ultimate gas recovery per well..................................................... 25 Discussion..................................................................................... 29 Conclusions.................................................................................... 32 References cited............................................................................... 36 Appendices..................................................................................... 47 ILLUSTRATIONS Page Figure 1. Map of the northern part of the Appalachian basin province (067) showing oil and gas plays in the Lower Silurian "Clinton" sands, Medina Group sandstones, and Tuscarora Sandstone identified in the 1995 USGS National Oil and Gas Assessment........................ 3 Figure 2. Map of the regional hydrocarbon accumulation in Lower Silurian sandstone reservoirs of the Appalachian basin, U.S. and Canada showing oil and gas fields used in the report. Also shown is the approximate boundary between discrete and basin-centered parts of the accumulation............................................................... 5 Figure 3. Correlation chart of Niagaran Provincial Series rocks (Lower to lower Upper Silurian) in the area of the regional accumulation............. 8 Figure 4. Plot of depth to production vs. hydrocarbon type for oil and gas fields................................................................................ 9 Figure 5. Map of the regional hydrocarbon accumulation in Lower Silurian sandstone reservoirs of the Appalachian basin showing oil and gas fields used in this report. Also shown is the approximate updip limit of the basin-centered (deep basin) gas accumulation and adjoining water-block trap of Davis (1984) and Zagorski (1991).......... 16 Figure 6. Plot of reservoir porosity vs. reservoir permeability for oil and gas fields........................................................................... 17 Figure 7. Plot of reservoir water saturation vs. depth to production for oil and gas fields. Also shown are the volume and salinity of produced waters.................................................................. 19 Figure 8. Plot of reservoir pressure vs. depth to production for oil and gas fields........................................................................... 24 Figure 9. Plot of bottom-hole temperature vs. depth to production for oil and gas fields.................................................................. 26 Figure 10. Probability plot of estimated ultimate recovery (EUR) of gas per well in the Northeast Salem field......................................... 28 Figure 11. EUR per well distributions for discrete and basin-centered parts of the regional accumulation........................................... 30 Figure 12. Generalized model of origin and modification of the Clinton/ Medina basin-centered gas accumulation and adjoining discrete and hybrid accumulations....................................................... 31 Figure 13. Map showing discrete, hybrid, and basin-centered parts of the Clinton/Medina/Tuscarora regional hydrocarbon accumulation........... 33 TABLES Page Table 1. Summary of oil and gas fields in Ohio, Pennsylvania, and New York that constitute the data set in this report........................................ 7 Table 2. Summary of local and regional structural elements imprinted on the north- to northeast-striking structural trend of the Appalachian basin...... 11 Table 3. Summary of trap types............................................................. 13 Table 4. Summary of produced water...................................................... 20 Table 5. Summary of gas and oil EUR per well distributions............................ 27 11 APPENDICES Data sheets for: Page Appendix A. Adams/Waterford/Watertown gas field, Washington County, Ohio.... 47 Appendix B. Athens gas field, Crawford County, Pennsylvania......................... 48 Appendix C. Best gas field, Portage and Mahoning Counties, Ohio.................... 49 Appendix D. Carbon Hill oil field, Hocking County, Ohio............................... 50 Appendix E. Claysville oil field, Guernsey County, Ohio................................. 51 Appendix F. Clayton oil field, Perry County, Ohio........................................ 52 Appendix G. Conneaut gas field (Indian Springs pool), Crawford County, Pennsylvania.................................................................... 53 Appendix H. Conneaut gas field (Kastle field), Crawford County, Pennsylvania.................................................................... 54 Appendix I. Cooperstown gas field, Venango and Crawford Counties, Pennsylvania..................................................................... 55 Appendix J. Cooperstown gas field (Oil Creek pool), Venango County, Pennsylvania..................................................................... 56 Appendix K. East Canton/Magnolia oil field, Stark and Carroll Counties, Ohio...... 57 Appendix L. Homer gas field, Licking and Knox Counties, Ohio....................... 58 Appendix M. Kantz Corners gas field, Crawford and Mercer Counties, Pennsylvania................................................................... 59 Appendix N. Lakeshore gas field, Chautauqua County, New York..................... 60 Appendix O. Lancaster/Sugar Grove gas field, Fairfield and Hocking Counties, Ohio.............................................................................. 61 Appendix P. Lenox gas field, Ashtabula County, Ohio.................................... 62 Appendix Q. Logan oil field, Hocking County, Ohio...................................... 63 Appendix R. Mantua/Shalersville gas field, Portage County, Ohio...................... 64 in Appendix S. Moreland oil field, Wayne County, Ohio.................................... 65 Appendix T. North Jackson/Lordstown gas field, Trumbull and Mahoning Counties, Ohio.................................................................. 66 Appendix U. Northeast Salem gas field, Mahoning County, Ohio....................... 67 Appendix V. Ravenna gas field, Portage County, Ohio................................... 68 Appendix W. Senecaville gas field, Guernsey County, Ohio............................. 69 Appendix X. Sharon Deep gas field, Mercer County, Pennsylvania and Trumbull County, Ohio................................................................... 70 Appendix Y. Yorktown/Clay gas field, Tuscarawas County, Ohio..................... 71 IV ABSTRACT Oil and gas trapped in Lower Silurian "Clinton" sands and Medina Group sandstone constitute a regional hydrocarbon accumulation that extends 425 mi in length from Ontario, Canada to northeastern Kentucky. The 125-mi width of the accumulation extends from central Ohio eastward to western Pennsylvania and west-central New York. Lenticular and intertonguing reservoirs, a gradual eastward decrease in reservoir porosity and permeability, and poorly segregated gas, oil, and water in the reservoirs make it very difficult to recognize clear-cut geologic- and production-based subdivisions in the accumulation that are relevant to resource assessment. However, subtle variations are recognizable that permit the regional accumulation to be subdivided into three tentative parts: a western gas-bearing part having more or less discrete fields; an eastern gas- bearing part having many characteristics of a basin-centered accumulation; and a central oil- and gas-bearing part with "hybrid" fields that share characteristics of both discrete and basin-centered accumulation. A data set of 25 oil and gas fields is used in the report to compare selected attributes of the three parts of the regional accumulation. A fourth part of the regional accumulation, not discussed here, is an eastern extension of basin-centered accumulation having local commercial gas in the Tuscarora Sandstone, a proximal facies of the Lower Silurian depositional
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