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A Comparative Study of the Mississippian Barnett Shale, Fort Worth Basin, and Devonian Marcellus Shale, Appalachian Basin

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A Comparative Study of the Mississippian Barnett Shale, Fort Worth Basin, and Devonian Marcellus Shale, Appalachian Basin DOE/NETL-2011/1478 A Comparative Study of the Mississippian Barnett Shale, Fort Worth Basin, and Devonian Marcellus Shale, Appalachian Basin U.S. DEPARTMENT OF ENERGY DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe upon privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. ACKNOWLEDGMENTS The authors greatly thank Daniel J. Soeder (U.S. Department of Energy) who kindly reviewed the manuscript. His criticisms, suggestions, and support significantly improved the content, and we are deeply grateful. Cover. Top left: The Barnett Shale exposed on the Llano uplift near San Saba, Texas. Top right: The Marcellus Shale exposed in the Valley and Ridge Province near Keyser, West Virginia. Photographs by Kathy R. Bruner, U.S. Department of Energy (USDOE), National Energy Technology Laboratory (NETL). Bottom: Horizontal Marcellus Shale well in Greene County, Pennsylvania producing gas at 10 million cubic feet per day at about 3,000 pounds per square inch. Photograph by Tom Mroz, USDOE, NETL, February 2010. A Comparative Study of the Mississippian Barnett Shale, Fort Worth Basin, and Devonian Marcellus Shale, Appalachian Basin By Kathy R. Bruner and Richard Smosna (URS Corporation) April 2011 DOE/NETL-2011/1478 U.S. Department of Energy ii Contents 1.0 EXECUTIVE SUMMARY ...............................................................................................................................1 1.1 Purpose ..................................................................................................................................................1 1.2 Summary ...............................................................................................................................................1 1.3 Outcrop Photographs of Barnett and Marcellus Shales .......................................................6 2.0 INTRODUCTION .........................................................................................................................................13 3.0 BARNETT SHALE, FORT WORTH BASIN, TEXAS ...............................................................................14 3.1 Location ..............................................................................................................................................14 3.2 Geological Setting ..........................................................................................................................14 3.2.1 Fort Worth Basin .................................................................................................................14 3.2.2 Stratigraphy .........................................................................................................................17 3.2.3 Tectonics and Structure ...................................................................................................23 3.2.4 Lithology and Lithofacies ...............................................................................................24 3.2.5 Depositional Environment .............................................................................................26 3.3 Petroleum Geology ........................................................................................................................27 3.3.1 Organic Carbon Content .................................................................................................27 3.3.2 Thermal Maturity and Burial History ...........................................................................28 3.3.3 Reservoir Characteristics .................................................................................................32 3.3.4 Generation of Hydrocarbons .........................................................................................34 3.3.5 Delineation of the Barnett Play .....................................................................................34 4.0 MARCELLUS SHALE, APPALACHIAN BASIN ......................................................................................37 4.1 Location ..............................................................................................................................................37 4.2 Geological Setting ..........................................................................................................................37 4.2.1 Appalachian Basin .............................................................................................................37 4.2.2 Stratigraphy .........................................................................................................................41 4.2.3 Tectonics and Structure ...................................................................................................51 4.2.4 Lithology and Lithofacies ...............................................................................................55 4.2.5 Depositional Environment .............................................................................................55 4.3 Petroleum Geology ........................................................................................................................58 4.3.1 U.S. Department of Energy’s Eastern Gas Shale Project .......................................58 4.3.2 Organic Carbon Content .................................................................................................59 4.3.3 Thermal Maturity and Burial History ...........................................................................60 4.3.4 Reservoir Characteristics .................................................................................................69 4.3.5 Generation of Hydrocarbons .........................................................................................72 4.3.6 Delineation of the Marcellus Play ................................................................................73 5.0 DRILLING AND STIMULATION TECHNIQUES ..................................................................................74 5.1 Fracture Stimulation ......................................................................................................................74 5.1.1 Natural Fractures and Faults ..........................................................................................74 5.1.2 Slickwater-Fracturing Treatment ..................................................................................76 5.1.3 Fracture Barriers .................................................................................................................77 5.1.4 Fracture Geometry and Fracture Mapping...............................................................78 5.2 Horizontal Drilling ..........................................................................................................................82 5.3 Well Performance ............................................................................................................................86 5.4 History of the Barnett Shale Play ...............................................................................................88 6.0 COMPARISON OF BARNETT AND MARCELLUS SHALES ..............................................................92 7.0 REFERENCES ...............................................................................................................................................95 iii Figures 1–5. Maps showing— 1. Location of Mississippian Barnett Shale, Fort Worth Basin, and Devonian Marcellus Shale, Appalachian Basin .............................................................13 2. Fort Worth Basin showing the major geological features that influence the Barnett Shale and structural contours. ................................................15 3. Stages of exploration in the Barnett Shale, 1998–2007 ............................................16 4. Regional paleogeography of the southern mid-continent region during the Late Mississippian (325 Ma), showing the approximate position of the Fort Worth Basin ........................................................................................16 5. Middle Mississippian paleogeographic map of the United States indicating that the Fort Worth Basin was relatively deep .........................................17 6–8. Diagrams showing— 6. Generalized stratigraphic column, Fort Worth Basin .................................................18 7. Lower Barnett member locally divided into 5 unit (A through E) packages of shale interbedded with limestone ...........................................................18 8. Two well logs in the Newark East Field ............................................................................19 9–10. Maps showing— 9. Extent of Barnett Shale in the Fort Worth Basin and (a) pinch-out line of middle Forestburg Limestone Member in orange, (b) pinch-out line of underlying
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