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. Clinkered coal bed—Identity or existence question- 1.2.34 Tops of V's follow trace able, location accurate ? 2.0 mm lineweight .2 mm color 100% red of bed; V's point down- ward stratigraphically. Clinkered coal bed—Identity and existence certain, 1.2.35 Add name if more than location approximate .375 mm one type is shown on ? map (see Section 1.4). Clinkered coal bed—Identity or existence question- May also be shown in 1.2.36 able, location approximate ? 2.0 2.0 black or other colors. mm mm

Clinkered coal bed—Identity and existence certain, 1.2.37 location inferred .375 mm ? Clinkered coal bed—Identity or existence question- 1.2.38 able, location inferred ? 2.0 2.0 mm mm Clinkered coal bed—Identity and existence certain, 1.2.39 location concealed ? Clinkered coal bed—Identity or existence question- 1.2.40 able, location concealed ? 2.0 2.0 mm mm

pattern 317-R Add name if more than 1.2.41 Area of clinkered coal bed contact [lineweight one type is shown on .15 mm] map (see Section 1.4). Outcrop areas may Outcrop area of key bed or bed of economically 100% black 1.2.42 scratch either overprint other important commodity (1st option) boundary [lineweight 0.0] geologic map units or be used as stand-alone Outcrop area of key bed or bed of economically 30% black geologic map units. 1.2.43 scratch important commodity (2nd option) boundary [lineweight 0.0] Each type of outcrop area may also be 100% green shown in other values of 1.2.44 Outcrop area of clay bed scratch boundary black or in other colors; [lineweight 0.0] add name(s) if more 100% red than one type is shown 1.2.45 scratch Outcrop area of coal bed boundary on map (see Section [lineweight 0.0] 1.4). *For more information, see general guidelines on pages A-i to A-v.

A–1–4 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* 1.3—Dikes color 100% red lineweight .25 mm Use when dike is too Dike (1st option)—Identity and existence certain, 1.3.1 narrow to show as an location accurate area at map scale. 3.5 mm Add map-unit labels to Dike (1st option)—Identity and existence certain, 1.3.2 dikes if needed (see location approximate Section 1.4); use a .75 mm queried label if identity color 100% red Dike (2nd option)—Identity and existence certain, of dike is questionable. 1.3.3 1.25 mm location accurate May also be shown in lineweight .25 mm 2.0 mm black or other colors. 3.5 mm Dike (2nd option)—Identity and existence certain, 1.3.4 location approximate .75 mm color 100% red Dike (3rd option)—Identity and existence certain, 90° 1.3.5 location accurate 1.0 mm lineweight .25 mm 4.25 mm 3.5 mm Dike (3rd option)—Identity and existence certain, 1.3.6 location approximate .75 mm color 100% red dot diameter Dike (4th option)—Identity and existence certain, 1.125 mm 1.3.7 location accurate lineweight .25 mm 4.25 mm 3.5 mm Dike (4th option)—Identity and existence certain, 1.3.8 location approximate .75 mm color 100% red circle diameter Dike (5th option)—Identity and existence certain, 1.175 mm 1.3.9 location accurate lineweight .25 mm 4.25 mm 3.5 mm Dike (5th option)—Identity and existence certain, 1.3.10 location approximate .75 mm color 100% red 1.125 mm Dike (6th option)—Identity and existence certain, 1.3.11 location accurate lineweight .25 mm 4.25 mm 3.5 mm Dike (6th option)—Identity and existence certain, 1.3.12 location approximate .75 mm 50% red contact [lineweight Although only "dike .15 mm] 1.3.13 Dike of variable thickness (2nd option)" is shown here, any type of dike fault [lineweight symbol may be used. 1.3.14 Dike intruding fault (1st option) .375 mm] Add map-unit labels to dikes if needed (see Section 1.4). contact [lineweight .15 mm] Thick dikes may also be 1.3.15 Dike intruding fault (2nd option) shown in other colors.

*For more information, see general guidelines on pages A-i to A-v.

A–1–5 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* 1.4—Line-symbol decorations and notations for contacts, key beds, and dikes Inclined contact, dike, key bed, clay bed, coal bed, 35 tick length 35 HI-6 Line-symbol decora- 1.75 mm; 1.4.1 or bed of economically important commodity (1st lineweight tions may be added to option)—Showing dip value and direction .15 mm any type or style of con- Inclined contact, dike, key bed, clay bed, coal bed, 15 tick length 15 tact, as well as to any 1.375 mm; .875 mm 1.4.2 or bed of economically important commodity (2nd type or style of key bed lineweight or dike (use proper line- option)—Showing dip value and direction .15 mm 30° weights, etc., to show Vertical or near-vertical contact, dike, key bed, clay tick length 2.5 mm; clay beds, coal beds, 1.4.3 bed, coal bed, or bed of economically important lineweight dikes, etc.). commodity (1st option) .15 mm Place tick, arrow, or oth- HI-6 Vertical or near-vertical contact, dike, key bed, clay 90 90 er line-symbol decora- 1.4.4 bed, coal bed, or bed of economically important tion where observation commodity (2nd option) was made. Overturned contact, dike, key bed, clay bed, coal 85 tick length 85 HI-6 Add arrowhead or '90' 1.75 mm; 1.4.5 bed, or bed of economically important commodity to ticks showing dip if lineweight .625 mm (1st option)—Showing dip value and direction .15 mm radius necessary for clarity. Overturned contact, dike, key bed, clay bed, coal 75 tick length 75 1.375 mm; .875 mm 1.4.6 bed, or bed of economically important commodity lineweight .625 mm (2nd option)—Showing dip value and direction .15 mm radius 30° Lineation on surface of contact, dike, key bed, clay 65 6.0 mm 65 HI-6 lineweight 1.4.7 bed, coal bed, or bed of economically important .175 mm commodity—Showing bearing and plunge 25° 1.5 mm HI-6 Lineation on surface of inclined contact, dike, key bed, 25 35 tick length 25 35 clay bed, coal bed, or bed of economically important 1.75 mm; 1.4.8 commodity—Tick shows contact dip value and direc- lineweight tion; arrow shows bearing and plunge of lineation .15 mm H-7 Contact—Showing relative age of intrusive or extru- Y 1.4.9 Y sive units where known: Y, younger; O, older O H-7 O 20° Contact—Showing location where contact is partic- 1.75 1.4.10 ularly well exposed in field mm .75 mm Key bed, clay bed, coal bed, bed of economically 1.5 1.5 H-6 Use proper lineweights, 1.4.11 important commodity, or dike—Showing thickness etc., to show clay beds, and location where measured coal beds, dikes, etc. HI-8 1.4.12 Key bed—Showing name ds ds

HI-8 (100% black) 1.4.13 Clay bed—Showing name sc sc

HI-8 Bed of economically important commodity— 1.4.14 gyp gyp Showing name

HI-8 (100% black) 1.4.15 Coal bed—Showing name lg lg

HI-8 (100% black) 1.4.16 Clinkered coal bed—Showing name m m

HI-8 bg (100% bg 1.4.17 Area of clinkered coal bed—Showing name black)

Km Km H-8 Although only "dike 1.4.18 Dike—Showing name (2nd option)" is shown leader lineweight .175 mm labeled here, map-unit H-8 labels may be added to KJd KJd? KJd KJd? any type of dike symbol. 1.4.19 Dike of variable thickness—Showing name leader lineweight .175 mm Use a queried map-unit label if identity of dike is H-8 Km Km questionable. 1.4.20 Dike intruding fault (1st option)—Showing name leader lineweight .175 mm Td H-8 Td 1.4.21 Dike intruding fault (2nd option)—Showing name leader lineweight .175 mm *For more information, see general guidelines on pages A-i to A-v.

A–1–6