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Salts in the Williston Basin, North Dakota

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Salts in the Williston Basin, North Dakota SALTS IN THE WILLISTON BASIN, NORTH DAKOTA Julie A. LeFever1 and Richard D. LeFever2 1North Dakota Geological Survey University Station Grand Forks ND 58202 2Department of Geology and Geological Engineering University of North Dakota Grand Forks ND 58202 Report of Investigations No. 103 NORTH DAKOTA GEOLOGICAL SURVEY Edward C. Murphy, State Geologist Lynn D. Helms, Director Dept of Mineral Resources 2005 i TABLE OF CONTENTS Illustrations ............................................................................................................................................. iii Abstract ................................................................................................................................................. 1 Introduction ............................................................................................................................................ 2 Methods ................................................................................................................................................. 2 Minor Salts ............................................................................................................................................. 3 Silurian ............................................................................................................................................. 3 Interlake Formation .................................................................................................................... 3 Devonian .......................................................................................................................................... 3 Ashern Formation ....................................................................................................................... 3 Souris River Formation ............................................................................................................... 5 Duperow Formation ................................................................................................................... 5 Mississippian .................................................................................................................................... 5 Charles Formation ...................................................................................................................... 5 Kibbey Formation ...................................................................................................................... 5 Major Salts .......................................................................................................................................... 13 Devonian ........................................................................................................................................ 13 Prairie Formation ...................................................................................................................... 13 Mississippian .................................................................................................................................. 13 Charles Formation .................................................................................................................... 13 Permian .......................................................................................................................................... 13 Opeche Formation .................................................................................................................... 13 Triassic (?) ...................................................................................................................................... 23 Spearfish Formation .................................................................................................................. 23 Jurassic .......................................................................................................................................... 23 Piper Formation ........................................................................................................................ 23 Salt Dissolution ..................................................................................................................................... 23 Recognition .................................................................................................................................... 23 Mechanisms ................................................................................................................................... 29 Dissolution ...................................................................................................................................... 29 Prairie Formation ............................................................................................................................ 32 Charles Formation .......................................................................................................................... 36 Opeche Formation .......................................................................................................................... 37 Spearfish Formation ........................................................................................................................ 37 Piper Formation .............................................................................................................................. 37 Hydrocarbon Traps .............................................................................................................................. 37 Summary .............................................................................................................................................. 38 References Cited .................................................................................................................................. 38 ii ILLUSTRATIONS Figure 1. Stratigraphic column of North Dakota ..................................................................................... 2 Figure 2. Index map showing the location of the study area .................................................................... 3 Figure 3. A.) Typical log characteristics of Interlake salts ....................................................................... 4 B.) Isopach of the combined Interlake salts ............................................................................ 4 Figure 4. A.) Typical log characteristics of Ashern salts .......................................................................... 6 B.) Isopach map of the N salts ............................................................................................... 6 C.) Isopach map of M salts .................................................................................................... 6 Figure 5. A.)Typical log characteristics of the Davidson salt, Souris River Formation .............................. 7 B.) Isopach map of the Davidson salt ...................................................................................... 7 Figure 6. A.)Typical log characteristics of the Flat Lake salt, Duperow Formation .................................. 8 B.) Isopach map of the Flat Lake salt ..................................................................................... 8 Figure 7. A.) Typical log characteristics of the Sherwood, Bluell, and Rival salts of the lower Charles Formation .............................................................................................................................. 9 B.) Isopach map of the Sherwood salt ................................................................................... 9 C.) Isopach map of the Bluell salt ........................................................................................ 10 D.) Isopach map of the Rival salt .......................................................................................... 10 E.) Typical log characteristics of the Midale salt ..................................................................... 11 F.) Areal distribution of the Midale salt .................................................................................. 11 Figure 8. A.) Typical log characteristics of the salt in the Kibbey Formation .......................................... 12 B.) Isopach map of the Kibbey salt....................................................................................... 12 Figure 9. A.) Typical log characteristics of the Prairie Formation showing the salt and four members. .... 14 B.) Isopach map of the Prairie salt ....................................................................................... 15 C.) Isopach map of the Second Red Bed.............................................................................. 15 Figure 10. A.) Composite well log showing the typical log characteristics of the Charles salts ................. 16 Figure 11. A.) Isopach map of the F1 salt ............................................................................................ 17 B.) Isopach map of the F salt................................................................................................ 17 C.) Isopach map of the E2 salt ............................................................................................ 18 D.) Isopach map of the E1 salt ............................................................................................. 18 E.) Isopach map of the E salt ............................................................................................... 19 F.) Areal distribution of the D1 salt ......................................................................................
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