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Lithologic Descriptions and Geophysical Logs of Coreholes in the Valley Coal Fields, Bland, Botetourt, Montgomery, Pulaski, Smyth, and Wythe Counties, Virginia

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Lithologic Descriptions and Geophysical Logs of Coreholes in the Valley Coal Fields, Bland, Botetourt, Montgomery, Pulaski, Smyth, and Wythe Counties, Virginia UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY TEST DRILLING FOR COAL IN 1982-83 IN THE JEFFERSON NATIONAL FOREST, VIRGINIA Part 3: Lithologic descriptions and geophysical logs of coreholes in the Valley coal fields, Bland, Botetourt, Montgomery, Pulaski, Smyth, and Wythe Counties, Virginia By Kenneth J. Englund, John C. Weber, Roger E. Thomas, and John F. Windolph, Jr. U.S. Geological Survey and James W. Dryden U.S. Bureau of Land Management Open-File Report 83-637 1983 This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or stratigraphic nomenclature CONTENTS Page Introduction .......................................................... 1 Location ............................................................. 1 Previous investigations................................................ 4 Present investigations ................................................ 4 Acknowledgements ...................................................... 4 Stratigraphy .......................................................... 15 Pre-Mississippian Paleozoic rocks, undivided ..................... 15 Price Formation .................................................. 15 Maccrady Shale ................................................... 17 Structural setting .................................................... 17 Lithologic descriptions and geophysical logs .......................... 17 Corehole V-l ..................................................... 18 Corehole V-2 ..................................................... 77 Corehole V-3 ..................................................... 95 Corehole V-4 ..................................................... 125 Corehole V-5 ..................................................... 152 Corehole V-5B (redrill) .......................................... 168 Corehole V-6 ..................................................... 177 Corehole V-6B (redrill) .......................................... 203 Corehole V-7 ..................................................... 215 Corehole V-8 ..................................................... 230 References ............................................................ 249 ILLUSTRATIONS Page Figure 1. Index map of coal fields in southwes ^ern Virginia .......... 2 2. Location of coreholes in the Valley fi^-al^TolHc*. ^ 3. Location of coreholes V-l and V-8 . ........................ 5 4. ........................ 6 5. Location of corehole V-3 ........... ........................ 7 6. ........................ 8 7. Location of coreholes V-5 and V-5B ( redrill) ............... 9 8. Location of coreholes V-6 and V-6B ( redrill) ............... 10 9. Location of corehole V-7 ........... ........................ 11 10. Generalized section of the Maccrady Shale and coal- bearing Price Formation ........... 1 2 11. Correlation and drilled intervals of coreholes in the ........................ 13 12. ........................ 14 TABLES Table 1. T ........................ 16 ii TEST DRILLING FOR COAL IN 1982-83 IN THE JEFFERSON NATIONAL FOREST, VIRGINIA Part 3: Lithologic descriptions and geophysical logs of coreholes in the Valley coal fields, Bland, Botetourt, Montgomery, Pulaski, Siayth, and Wythe Counties, Virginia Kenneth J. Englund, John C. Weber, Roger E. Thomas, and John F. Windolph, Jr. U.S. Geological Survey and James W. Dryden, U.S. Bureau of Land Management Introduction Coreholes were drilled at 21 sites in the Jefferson National Forest of southwestern Virginia for the U.S. Bureau of Land Management. Drilling was in progress from October, 1982 to February, 1983 to determine the general distribution, thickness, and quality of potentially minable coal on Federal mineral properties in the southwestern Virginia and Valley coal fields (fig. 1). The results of drilling in the southwestern Virginia coal field are presented in Parts 1 (Englund and others, 1983) and 2 (Simon and Englund, 1983a) of this program. The results of drilling in the Valley coal fields are presented in Part 3 (this report) which includes descriptive lithologic data, correlations, and geophysical logs and in Part 4 which includes the analyses of the coal cores (Simon and Englund, 1983b). Coreholes were drilled at eight widely spaced sites in the Valley coal fields along two discontinuous outcrop belts of the coal-bearing Price Formation of Early Mississippian age. Partial redrills were made at three of these sites in attempts to recover additional coal from beds with significant core loss. Location Federal mineral properties in the Valley coal fields are located principally in two discontinuous northeast-trending belts: (1) along Brush Mountain in Montgomery and Pulaski Counties and Brushy Mountain in Wythe County with a northeast extension along North Mountain in Botetourt County and a southeasterly extension along Caseknife and Brushy Ridges in Pulaski and Wythe Counties and (2) along Brushy and Little Brushy Mountains in Bland and Siayth Counties (fig. 2). Within these belts, the locations and depths 78° 38° 82' SOUTHWESTERN VIRGINIA COAL FIELD 83* VALLEY COAL FIELDS 60 0 BO MILES ' 60 6 60 KILOMETERS Figure 1. Index map of coal fields in southwestern Virginia .' OTETOimr COUNTY I XPLAHATION 0*l«>HI*. V. Giti.kl. V*. MtO«»l«o Mill. V«. C'*ck.ll, V.. Ch.lhxn HIM.'Vi \\ » x-* TAIEWELL COUNTY BLAND COUNTY I* JO'00" «' 2J 30" *)i"_iy*nr 0000 rg A 0 6 Mill* 0 6 Kilometer* WYTHf COUNTY SCALE ft' II" 17 30" II'JOOO1' «I'2J30" \ If ISW ll'OT'JO- \ SUYTM COUNTY Figure 2 . Location of coreholes in the Valley coal fields. Stippled pattern indicates approximate areas of Federal mineral ownership in proximity of drill sites. of coreholes were chosen to test the coal-bearing Price Formation. Site selection was also based on readily available acctess and proximity to a source of drilling water. Previous investigations The coal-bearing strata of the Valley coal ields were assigned to the Price Formation by Campbell (1894, p. 77). In a later report, Campbell (1925) mapped the Price Formation and described the gen ral geology, geologic struc- ture, and economic geology of coal field areas, Regional geologic investiga- tions by Butts (1933, 1940) and Cooper (1961) al o included maps and descrip- tions of the Price Formation. The most recent r jports dealing with the Price Formation include geologic mapping (Bartho omew and Loury, 1979) and a coal-bed methane evaluation (Stanley and Schultz 1983) in the Blacksburg, Virginia area. Present investigations This core drilling program in the Jefferson National Forest was initiated and funded by the U.S. Bureau of Land Management and implemented by the U.S. Geological Survey (USGS). The drilling was cont acted to Joy Manufacturing Company of LaPorte, Indiana by the USGS and the ;eophysical logging was sub- contracted to Riley, Mannon, and Sturgeon, Ltd. f Huntington, West Virginia, USGS field personnel were on-site during the dri ling to measure, describe, and box the core and to sample the coal cores; X ray radiographs were used to identify partings in the coal cores prior to ana ysis. The locations of coreholes and the generalized geology in the vie nity of the drill sites are shown in Figures 3 to 9. A generalized geologic section of the Price Formation and the Maccrady Shale is indicated in Figure 10 and the correlation and drilled interval of each corehole are shown in F gure 11. An explanation for figures 3 to 9 is presented in Figure 12. Upon ompletion of the core drilling and geophysical logging, the coreholes were cemented and the sites were restored and seeded by the drilling contrac or. Acknowledgements The cooperation of U.S. Forest Service pers nnel in the Jefferson National Forest is gratefully acknowledged. Special than] cs are due to W.D. Blackburn, J.F. Mclntyre, and D. Polick for their aid in th selection, preparation, and restoration of drill sites. The writers also wi h to thank their associates in the USGS for assistance during the drilling p ogram, especially: J.Q. Maberry, J.M. Back, and P.C. Lyons for describin and sampling drill core, P.L. Johnson for aid in formating core descriptions and R.W. Stanton and T.A. Moore for preparing X-ray radiographs of coal co es. Also, sincere apprecia- tion is extended to private and corporate landowiers for information and access provided to the drill sites. 80° 0 1 '00' 79° 59'00' 37° 30'00* 37° SO'OO' TOURT COUNTY 37° 28*00' 37° 28'00' 80° 01*00' 79° 59*00' Figure 3. Location of coreholes V-l and V-8. See Figure 12 for explanation. 80° 20*00* 80° 18'00' 37° 19'30' 37° 19'30' MONTGOMERY 37° 17*30' 37° 17'30' 80° 20*00' 80° 1 8*00' Figure 4. Location of corehole V-2. See Figure 12 for explanation 80° 52'30* 80° 50'30* 37° 02'00' 37° 02'00 ,. -- CO 27.0V-3/T PULASKICOUNT i i i i 0.5 Kilometer 37' OO'OO 1 80° 52*30 80° 50'30* Figure 5. Location of corehole V-3. See Figure 12 for explanation. 8 1 ° 3 1 '30' 8 1 ° 29'30' 37° OO'OO' 37° OO'OO' SMYTH COUNTY 0.5 Mile 1 1 L I 36' 58*00* 36° 58'00' 81° 31*30' 81° 29*30' Figure 6. Location of corehole V-4. See Fijjure 12 for explanation. 8 1° 25*00* 8 1 ° 23'00* 37° 0 TOO* 37° 0 TOO 1 0 0.5 Mile I I i i BLAND COUNTY 36° 59'00* 36° 59*00' 81° 25*00* 81° 23'00* Figure 7. Location of coreholes V-5 and V-5B (rcdrHl) 12 for explanation. 8 1° 14'30" 81° 12'30* 36° 59*00* 36° 59'00' .o WYTHE COUNTY Mp 36° 57*00' 36° 57*00' 8 1° 14*30* 81° 12*30' Figure 8. Location of coreholea V-6 and VH6B (redrill). See Figure 12 for explanation. 10 8 1% 1 7'00' 81° 15'00* 36° 59'30* 36° 5 9'30' WYTHE COUNTY 0 0.5 Mile i i II i I T I I I i 0 0.5 Kilometer 36° 57*30* 36° 57'30' 81° 17'00' Figure ?. Location of corehole V-7. See Figure 12 for explanation. 11 OQc H fP MISSISSIPPIAN SYSTEM LOWER MISSISSIPPIAN SERIES coal-bearingPriceFor Generalizedsectionof MACCRADY PRICE FORMATION SHALE 2 i LITHOLOGY rt ;;- ! :: i H- fl> Merrimac coal zone ZONE Marine zones Langhorne coal zone O O H 1 ^-J p o 'o^ 5o3» p- i i « i i i i i j i THICKNESS OF ^ COAL IN INCHES C/3 & f" H THICKNESS fD 1654- IN FEET fU 1075-h 0ex- EXPLANATION I MV-I M M*trlm«c C««l Zone L LingKorn* Co«l Z«n* «> M«/ln* Fo»»M Zone CAMBRIAN ELBHOOK FORMATION (7) Merrimac Coal Zooq______(DATUM) \ co CO 03 SCALE Marine Foitll Zon»» 10 Kilometer* Figure 11.
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