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1—CONTACTS, KEY BEDS, and DIKES REF NO DESCRIPTION SYMBOL CARTOGRAPHIC SPECIFICATIONS* NOTES on USAGE* 1.1—Contacts

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1—CONTACTS, KEY BEDS, and DIKES REF NO DESCRIPTION SYMBOL CARTOGRAPHIC SPECIFICATIONS* NOTES on USAGE* 1.1—Contacts Federal Geographic Data Committee FGDC Document Number FGDC-STD-013-2006 FGDC Digital Cartographic Standard for Geologic Map Symbolization Appendix A 1—CONTACTS, KEY BEDS, AND DIKES REF NO DESCRIPTION SYMBOL CARTOGRAPHIC SPECIFICATIONS* NOTES ON USAGE* 1.1—Contacts Contact—Identity and existence certain, location lineweight .15 mm 1.1.1 accurate H-8 ? Contact—Identity or existence questionable, loca- 1.1.2 ? .75 mm tion accurate 12.0 mm Contact—Identity and existence certain, location 1.1.3 approximate 3.5 mm ? Contact—Identity or existence questionable, loca- 1.1.4 tion approximate ? .75 mm .75 mm Contact—Identity and existence certain, location 1.1.5 1.5 mm inferred ? Contact—Identity or existence questionable, loca- 1.1.6 ? tion inferred .75 mm .75 mm Contact—Identity and existence certain, location 1.1.7 .5 mm concealed ? Contact—Identity or existence questionable, loca- 1.1.8 ? tion concealed .75 mm .75 mm Use to delineate individ- Internal contact—Identity and existence certain, lineweight .15 mm .25 mm 1.1.9 ual debris flows, land- location accurate H-6 slide blocks, alluvial ? fans, etc., within the Internal contact—Identity or existence question- same geologic map 1.1.10 ? .5 mm able, location accurate 10.0 mm unit. Internal contact—Identity and existence certain, .25 mm 1.1.11 location approximate 4.0 mm ? Internal contact—Identity or existence question- ? .5 mm 1.1.12 able, location approximate .5 mm Internal contact—Identity and existence certain, .25 mm 1.1.13 2.0 mm location inferred ? Internal contact—Identity or existence question- 1.1.14 ? .5 mm able, location inferred .5 mm Internal contact—Identity and existence certain, .25 mm 1.1.15 .75 mm location concealed ? Internal contact—Identity or existence question- 1.1.16 ? .5 mm able, location concealed .5 mm Use to indicate a gradu- Gradational contact—Identity and existence certain, hachure lineweight .15 mm 1.1.17 .4 mm al or continuous litho- location accurate H-8 logic change from one ? 1.25 mm geologic map unit to Gradational contact—Identity or existence ques- 1.1.18 ? another. tionable, location accurate 2.0 mm Gradational contact—Identity and existence certain, 1.1.19 .4 mm location approximate ? Gradational contact—Identity or existence ques- 1.1.20 tionable, location approximate ? 2.0 mm 2.0 mm Gradational contact—Identity and existence certain, 1.1.21 .4 mm location inferred ? Gradational contact—Identity or existence ques- 1.1.22 tionable, location inferred ? 2.0 2.0 mm mm Gradational contact—Identity and existence certain, 1.1.23 .4 mm location concealed ? Gradational contact—Identity or existence ques- 1.1.24 tionable, location concealed ? 2.0 2.0 mm mm A–1–1 *For more information, see general guidelines on pages A-i to A-v. Federal Geographic Data Committee FGDC Document Number FGDC-STD-013-2006 FGDC Digital Cartographic Standard for Geologic Map Symbolization Appendix A 1—CONTACTS, KEY BEDS, AND DIKES (continued) REF NO DESCRIPTION SYMBOL CARTOGRAPHIC SPECIFICATIONS* NOTES ON USAGE* 1.1—Contacts (continued) Unconformable contact—Identity and existence lineweight lineweight May be used to show 1.1.25 .15 mm .125 mm certain, location accurate H-6 paraconformaties or disconformaties. Not ? .725 mm intended for use to Unconformable contact—Identity or existence ques- .75 show angular uncon- 1.1.26 ? mm 1.4 tionable, location accurate 12.0 mm mm formities or noncon- formities. Unconformable contact—Identity and existence Boundary of geologic 1.1.27 3.5 mm certain, location approximate map unit is center line ? (solid or dashed), not Unconformable contact—Identity or existence ques- "sine-wave"-style line. 1.1.28 ? tionable, location approximate .75 mm .75 mm Unconformable contact—Identity and existence 1.1.29 certain, location inferred 1.5 mm ? Unconformable contact—Identity or existence ques- 1.1.30 ? tionable, location inferred .75 mm .75 mm Unconformable contact—Identity and existence 1.1.31 certain, location concealed .5 mm ? Unconformable contact—Identity or existence ques- 1.1.32 ? tionable, location concealed .75 mm .75 mm Incised-scarp sedimentary contact—Identity and all lineweights .15 mm Use to show where a 2.0 mm 1.1.33 younger surficial geo- existence certain, location accurate. Hachures H-8 point downscarp 1.0 logic unit has been ? mm Incised-scarp sedimentary contact—Identity or deposited on an ero- sional scarp that has 1.1.34 existence questionable, location accurate. Hach- .75 ? mm ures point downscarp 12.0 mm been incised into an older surficial geologic Incised-scarp sedimentary contact—Identity and unit. 1.1.35 existence certain, location approximate. Hachures 3.5 mm point downscarp ? Incised-scarp sedimentary contact—Identity or 1.1.36 existence questionable, location approximate. ? .75 mm .75 mm Hachures point downscarp *For more information, see general guidelines on pages A-i to A-v. A–1–2 Federal Geographic Data Committee FGDC Document Number FGDC-STD-013-2006 FGDC Digital Cartographic Standard for Geologic Map Symbolization Appendix A 1—CONTACTS, KEY BEDS, AND DIKES (continued) REF NO DESCRIPTION SYMBOL CARTOGRAPHIC SPECIFICATIONS* NOTES ON USAGE* 1.2—Key beds Key bed—Identity and existence certain, location lineweight .2 mm Use to show key beds 1.2.1 accurate H-8 that are too narrow to map as an area at map ? scale. Key bed—Identity or existence questionable, loca- 1.2.2 ? .75 mm Add name of geologic tion accurate 12.0 mm map unit if more than one type of key bed is Key bed—Identity and existence certain, location shown on map (see 1.2.3 approximate 3.5 mm Section 1.4). ? May also be shown in Key bed—Identity or existence questionable, loca- color. 1.2.4 tion approximate ? .75 mm .75 mm Key bed—Identity and existence certain, location 1.2.5 1.5 mm inferred ? Key bed—Identity or existence questionable, loca- 1.2.6 tion inferred ? .75 mm .75 mm Key bed—Identity and existence certain, location 1.2.7 .5 mm concealed ? Key bed—Identity or existence questionable, loca- 1.2.8 tion concealed ? .75 mm .75 mm Clay bed—Identity and existence certain, location lineweight .3 mm color 100% green Use to show clay beds 1.2.9 accurate that are too narrow to HB-8 (100% green) map as an area at map ? scale. Clay bed—Identity or existence questionable, loca- 1.2.10 ? .75 mm Add name if more than tion accurate 12.0 mm one type is shown on map (see Section 1.4). Clay bed—Identity and existence certain, location 1.2.11 3.5 mm May also be shown in approximate black or other colors. ? Clay bed—Identity or existence questionable, loca- 1.2.12 tion approximate ? .75 mm .75 mm Clay bed—Identity and existence certain, location 1.2.13 1.5 mm inferred ? Clay bed—Identity or existence questionable, loca- 1.2.14 tion inferred ? .75 mm .75 mm Clay bed—Identity and existence certain, location 1.2.15 .5 mm concealed ? Clay bed—Identity or existence questionable, loca- 1.2.16 tion concealed ? .75 mm .75 mm Bed of economically important commodity—Identity lineweight .3 mm Use to show such eco- 1.2.17 and existence certain, location accurate HB-8 nomically important beds as gypsum, salt, ? bentonite, phosphate, or Bed of economically important commodity—Identity 1.2.18 ? .75 mm limestone that are too or existence questionable, location accurate 12.0 mm narrow to map as an area at map scale. Bed of economically important commodity—Identity Do not use to show coal 1.2.19 and existence certain, location approximate 3.5 mm beds (see Section 1.2, ? ref. nos. 1.2.25-40). Bed of economically important commodity—Identity Add name of commodi- 1.2.20 or existence questionable, location approximate ? .75 mm .75 mm ty if more than one type is shown on map (see Section 1.4). Bed of economically important commodity—Identity 1.2.21 1.5 mm and existence certain, location inferred May also be shown in color. ? Bed of economically important commodity—Identity 1.2.22 or existence questionable, location inferred ? .75 mm .75 mm Bed of economically important commodity—Identity 1.2.23 .5 mm and existence certain, location concealed ? Bed of economically important commodity—Identity 1.2.24 or existence questionable, location concealed ? .75 mm .75 mm A–1–3 *For more information, see general guidelines on pages A-i to A-v. Federal Geographic Data Committee FGDC Document Number FGDC-STD-013-2006 FGDC Digital Cartographic Standard for Geologic Map Symbolization Appendix A 1—CONTACTS, KEY BEDS, AND DIKES (continued) REF NO DESCRIPTION SYMBOL CARTOGRAPHIC SPECIFICATIONS* NOTES ON USAGE* 1.2—Key beds (continued) Coal bed—Identity and existence certain, location lineweight .3 mm color 100% red Use to show coal beds 1.2.25 accurate that are too narrow to HB-8 (100% red) map as an area at map ? scale. Coal bed—Identity or existence questionable, loca- 1.2.26 ? .75 mm Add name if more than tion accurate 12.0 mm one type is shown on map (see Section 1.4). Coal bed—Identity and existence certain, location 1.2.27 3.5 mm May also be shown in approximate black or other colors. ? Coal bed—Identity or existence questionable, loca- 1.2.28 tion approximate ? .75 mm .75 mm Coal bed—Identity and existence certain, location 1.2.29 1.5 mm inferred ? Coal bed—Identity or existence questionable, loca- 1.2.30 tion inferred ? .75 mm .75 mm Coal bed—Identity and existence certain, location 1.2.31 .5 mm concealed ? Coal bed—Identity or existence questionable, loca- 1.2.32 tion concealed ? .75 mm .75 mm Clinkered coal bed—Identity and existence certain, Use to show clinkered 1.2.33 H-8 (100% red) coal beds that are too location accurate .375 mm 90o narrow to map as an .8 mm ? area at map scale.
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