Osdf
certain
DS1
Medium to medium dark gray, medium-bedded, ribbony and oolitic lime mudstone to packstone.  Near the base of the member ribbony lime mudstone predominate. This member commonly forms a persistent and mappable ridge and is frequently well-exposed.
MUP_1
Stonehenge Formation, Dam Five Member
Osf
The lower part of the member is composed of massive, medium gray, algal lime boundstone.  Grading upsection into interbedded medium to dark gray algal thrombolites and medium gray, lime wackestone to lime packstone.
MUP_2
Stonehenge Formation, Funkstown Member
Oss
Dark-gray, argillaceous, thinly bedded to ribbony, lime mudstone with thin beds of flat-pebble lime grainstone conglomerate and hummocky, discontinuous, laminated limestone.
MUP_3
Stonehenge Formation, Stoufferstown Member
Ccsg
_csg
Interbedded, medium- to light-gray, ribbony lime mudstone that weathers to flaggy to platy beds, and arenaceous grainstones exhibiting edgewise and flat-pebble conglomerates. Locally, thin pastel blue and pink marble strata are developed.
MUP_4
Conococheague Formation, Shady Grove Member
Orr
Interbedded and cyclic limestone and dolomite, cherty in the lower 400 feet (120 m).  Limestone intervals consist of medium to light gray, ribbony and thrombolitic to stromatolitic, lime mudstone to boundstone.
MUP_5
Rockdale Run Formation
MUP_6
MUP_7
MUP_8
Ops
Light gray to tan, medium-bedded, highly fractured, fine-grained dolomite.  Weathers to a very light gray to buff surface.  Interbedded with very light gray, laminated dolomite.
MUP_9
Pinesburg Station Dolomite
Osp
Massive, light-gray lime mudstone containing fenestral fabric at the base (Row Park Limestone), overlain by interbedded, medium- to light-gray, medium-bedded limestone and laminated dolomitic limestone at the top (New Market Limestone).
MUP_10
St. Paul Group (undivided)
Oc
Medium- to dark-gray, nodular- to medium-bedded, fossiliferous limestone.
MUP_11
Chambersberg Formation
MUP_12
MUP_13
MUP_14
MUP_15
MUP_16
MUP_17
Oml
Predominately medium to dark gray, fissile shale with thin (<0.5 inches, 1 cm) siltstone interbeds.  Dark gray to black shale at base equivalent to the Utica Shale.
MUP_18
Martinsburg Formation, lower member
MUP_19
MUP_20
MUP_21
MUP_22
MUP_23
MUP_24
MUP_25
MUP_26
MUP_27
MUP_28
MUP_29
Ccz
_cz
Predominantly cyclically bedded, medium- to dark-gray, thrombolitic limestone and gray, ribbony and laminated limestone and tan, laminated dolomite.
MUP_30
Conococheague Formation, Zullinger Member
MUP_31
MUP_32
MUP_33
Interbedded and cyclic limestone and dolomite, cherty in the lower 400 feet (120 m). Limestone intervals consist of medium to light gray, ribbony and thrombolitic to stromatolitic, lime mudstone to boundstone.
MUP_34
MUP_35
MUP_36
MUP_37
MUP_38
MUP_39
Ccb
_cb
Tan, massive dolomite interbedded with tan to light-gray, laminated dolomite; unit characterized by dark-brown weathering.
MUP_40
Conococheague Formation, Big Spring Station Member
MUP_41
Ce
_e
Cyclically bedded, gray, thrombolitic limestone and ribbony to laminated limestone and dolomite, overlying cyclic, dark-gray limestone and dolomitic limestone and thick-bedded limestone and dolomite.
MUP_42
Elbrook Formation
MUP_43
MUP_44
MUP_45
MUP_46
MUP_47
MUP_48
MUP_49
MUP_50
CZscmp
_Zscmp
Light bluish-gray, dusky yellow, and moderate orange pink, muscovite-chlorite phyllite containing albite porphyroblasts, quartz, and hematite dust. Contains minor metasiltstone.
MUP_51
Sams Creek Muscovite Phyllite
Trni
^ni
Light reddish-gray, subangular to subrounded, quartz and limestone conglomerate.
MUP_52
New Oxford Formation, Irishtown Member
CZsctp
_Zsctp
Grayish red-purple and bluish-gray, variegated, vesicular phyllite with light-gray streaks and blebs of tuffaceous phyllite.
MUP_53
Sams Creek Formation, tuffaceous phyllite
CZscm
_Zscm
Brownish-gray to grayish-reddish-purple, massive to thin-bedded, calcitic and dolomitic marble containing quartz sand. Includes minor calcareous metasiltstone.
MUP_54
Sams Creek Formation, marble
MUP_55
CZscsr
_Zscsr
Medium to dark bluish-gray, fine-grained, thin-bedded to laminated, siliceous to argillaceous or micaceous limestone, interbedded with minor amounts of black to silvery gray phyllite.
MUP_56
Sams Creek Group, Silver Run Limestone Member
MUP_57
MUP_58
MUP_59
CZscb
_Zscb
Dark greenish-gray to medium bluish-gray, aphanitic to porphyritic, massive to schistose metabasalt composed of chlorite, epidote, quartz, altered plagioclase, actinolite, hornblende, and albite.
MUP_60
Sams Creek Formation, metabasalt
MUP_61
MUP_62
CZscq
_Zscq
Light-gray to grayish-green, medium-grained, thin-bedded to massive quartzite and minor calcareous sandstone. Contains detrital plagioclase, orthoclase, and polymictic quartz.
MUP_63
Sams Creek Formation, quartzite
MUP_64
MUP_65
MUP_66
MUP_67
MUP_68
MUP_69
MUP_70
MUP_71
MUP_72
MUP_73
MUP_74
MUP_75
MUP_76
MUP_77
MUP_78
MUP_79
MUP_80
MUP_81
MUP_82
MUP_83
MUP_84
MUP_85
MUP_86
MUP_87
MUP_88
MUP_89
MUP_90
MUP_91
MUP_92
MUP_93
MUP_94
MUP_95
MUP_96
MUP_97
MUP_98
MUP_99
MUP_100
MUP_101
MUP_102
MUP_103
MUP_104
MUP_105
MUP_106
MUP_107
MUP_108
MUP_109
MUP_110
MUP_111
MUP_112
CZwm
_Zwm
Predominately white to gray, massive to banded or bedded crystalline marble, but also contains dark-gray, bluish-gray, pale green, and purple marble and interbeds of green and purple phyllite.
MUP_113
Wakefield Marble
MUP_114
MUP_115
MUP_116
MUP_117
MUP_118
MUP_119
MUP_120
MUP_121
MUP_122
MUP_123
MUP_124
MUP_125
MUP_126
MUP_127
MUP_128
MUP_129
MUP_130
MUP_131
MUP_132
MUP_133
MUP_134
MUP_135
MUP_136
MUP_137
MUP_138
CZscqp
_Zscqp
Light-tan to light grayish-green to light silvery gray muscovite phyllite quartzite.
MUP_139
Sams Creek Formation, quartzite within phyllite
MUP_140
MUP_141
MUP_142
MUP_143
MUP_144
MUP_145
MUP_146
MUP_147
MUP_148
MUP_149
MUP_150
MUP_151
MUP_152
MUP_153
MUP_154
MUP_155
MUP_156
MUP_157
MUP_158
MUP_159
MUP_160
MUP_161
MUP_162
MUP_163
MUP_164
MUP_165
MUP_166
MUP_167
MUP_168
MUP_169
MUP_170
MUP_171
MUP_172
MUP_173
MUP_174
MUP_175
MUP_176
MUP_177
MUP_178
MUP_179
MUP_180
MUP_181
MUP_182
MUP_183
Cwb
_wb
Light-gray to medium-gray, medium-bedded quartzite with dark-gray, argillaceous layers up to 4 cm thick separating the quartzite beds. Cross-bedding within individual quartzite strata is pervasive.
MUP_184
Weverton Formation, Buzzard Knob Member
Cwo
_wo
Dark to very dark gray, very coarse grained to conglomeratic, cross-bedded graywacke.
MUP_185
Weverton Formation, Owens Creek Member
Ch
_h
Mainly phyllitic shale and siltstone, highly cleaved, dark green-gray, weathers tan; lesser amounts of metasandstones and impure gray quartzites
MUP_186
Harpers Formation
Cfu
_fu
Medium- to dark-gray, thin- to medium-bedded, pyritic, argillaceous limestone and shaly limestone. Contains intervals of tan-weathering dolomitic shale and sandy brecciated limestone.
MUP_187
Frederick Formation, undivided
Trgc
^gc
Limestone conglomerate marks the western edge of the Gettysburg Basin in Maryland and is similar in appearance and position to the Leesburg Formation in the Culpeper Basin.
MUP_188
Gettysburg Formation, conglomerate
Trg
^g
Reddish-brown to reddish-gray, locally greenish-gray, medium-grained siltstone, claystone, mudstone, and fine-grained sandstone.
MUP_189
Gettysburg Formation
CZl
_Zl
Medium- to dark-gray, medium-bedded conglomerate and black, tuffaceous phyllite.
MUP_190
Loudoun Formation
MUP_191
MUP_192
Cwm
_wm
Thin (less than 33 feet; 10 m), medium- to dark-gray quartzite and graywacke interbedded with very dark gray, highly cleaved siltstone and phyllitic shale.
MUP_193
Weverton Formation, Maryland Heights Member
MUP_194
Trns
^ns
Interbedded, light reddish-gray to reddish-brown sandstone. Sandstones exhibit sharp bases with shale-pebble lag conglomerates, and fining upward character.
MUP_195
New Oxford Formation, sandstone
MUP_196
MUP_197
Cfr
_fr
Interbedded dark-gray, thinly bedded, lime mudstone and black dolomitic shale, massive, medium-gray polymictic breccias, medium-gray sandy limestone, and dark-gray, flaggy lime mudstone.
MUP_198
Frederick Formation, Rocky Springs Station Member
MUP_199
MUP_200
MUP_201
MUP_202
MUP_203
MUP_204
MUP_205
MUP_206
Cfa
_fa
Thinly interbedded, medium dark gray to dark-gray, argillaceous, fine-grained limestone and dusky yellow to medium dark gray, silty dolomite.
MUP_207
Frederick Formation, Adamstown Member
Cfrb
_frb
Massive, medium-gray, sandy, polymictic breccias on the western flank of the synclinorium but are not evident on the east flank.
MUP_208
Frederick Formation, Rocky Springs Station breccia
Jd
Medium- to dark-gray, medium- to fine-grained diabase, weathering to rusty orange-brown spheroidal boulders and cobbles.
MUP_209
Jurassic Dikes
MUP_210
MUP_211
MUP_212
MUP_213
MUP_214
CZip
_Zip
Light olive-gray and greenish-gray, chlorite phyllite and metasiltstone.
MUP_215
Ijamsville Chlorite Phyllite
CZi
_Zi
Dusky blue, grayish-blue, very dusky red-purple, greenish-gray to pale olive phyllite, phyllonite, and minor slate. Phyllite contains mostly muscovite and chlorite. Lustrous sheen from mica and dark color results from abundant hematite dust.
MUP_216
Ijamsville Phyllite
Car
_ar
Thickly bedded, greenish-black to grayish-black, very fine-grained to fine-grained, burrow-mottled silty sandstone, interbedded with medium-gray to grayish-black, phyllitic shales 1 to 3 m thick.
MUP_217
Araby Formation
MUP_218
CZic
_Zic
Light-gray and green, medium- to coarse-grained metagraywacke with white quartz pebbles, variegated phyllite, and green chloritic matrix.
MUP_219
Ijamsville Phyllite, conglomeratic metagraywacke
MUP_220
MUP_221
MUP_222
MUP_223
MUP_224
Cfm
_fm
Thickly interbedded, black, platy shale, rubbly, dolomitic breccia, laminated lime mudstone, and black shale. A laterally continuous black shale marks the top of the member.
MUP_225
Frederick Formation, Monocacy Member
Cfms
_fms
Black shale that marks the top of the Monocacy Member and is more than 50 feet (15 m) thick.
MUP_226
Frederick Formation, Monocacy Member, shale bed
MUP_227
MUP_228
MUP_229
Ogw
Thin-bedded, dark-gray, fine-grained limestone interbedded with medium-bedded, bioturbated, dark-gray, fine-grained limestone, and thin, wavy bedded limestone with tan, dolomitic partings.
MUP_230
Grove Formation, Woodsboro Member
Ogf
Very thickly bedded, medium light gray, locally sandy, thrombolitic and stromatolitic algal limestone and medium-gray, laminated dolomitic limestone and olive-gray dolomite.
MUP_231
Grove Formation, Fountain Rock Member
Cfl
_fl
Interbedded, thinly laminated to thinly bedded, dark-gray, fine-grained limestone, calcareous shale, and medium-bedded fine-grained limestone, and thickly interbedded with medium dark gray, fine-grained limestone with wavy bedding and stromatolitic beds.
MUP_232
Frederick Formation, Lime Kiln Member
MUP_233
MUP_234
MUP_235
MUP_236
MUP_237
MUP_238
MUP_239
MUP_240
MUP_241
Ogc
Medium light gray to medium-gray, thick-bedded and cross-bedded, arenaceous limestone and sandy, dolomitic limestone with thin interbeds (1 ft or 0.3 m) of medium light gray, sandy, thrombolitic dolomite.
MUP_242
Grove Formation, Ceresville Member
MUP_243
MUP_244
MUP_245
MUP_246
Ogfs
Two cross-bedded sandstone units recognized in the middle of the formation were identified and traced.
MUP_247
Grove Formation, Fountain Rock Member, sandstone
MUP_248
MUP_249
MUP_250
MUP_251
MUP_252
MUP_253
MUP_254
MUP_255
MUP_256
MUP_257
MUP_258
MUP_259
MUP_260
MUP_261
MUP_262
MUP_263
MUP_264
MUP_265
MUP_266
Cwac
_wac
Reddish-brown to chocolate-brown, silty shale, siltstone, and silty fine-grained sandstone, interbedded with white, calcareous, Skolithus-burrowed sandstone beds and tan to buff, medium-bedded, sandy dolostone.
MUP_267
Waynesboro Formation, Chewsville Member
Cwak
_wak
Medium- to thick-bedded, medium- to coarse-grained, intraclastic grainstone; tan, laminated dolostone and dolomitic limestone; and medium-gray, oolitic, lime grainstone, ribbony carbonates, and burrowed-mottled dolomitic limestone.
MUP_268
Waynesboro Formation, Cavetown Member
Cwar
_war
Interbedded, tan-weathering, punky, fine-grained sandstones; green-gray shale; gray sandy limestone; and laminated dolostone.
MUP_269
Waynesboro Formation, Red Run Member
Ctd
_td
Interbedded and cyclical dolomite and limestone. Cycles consist of alternations of dark-gray, bioturbated dolomite and medium- to dark-gray, laminated dolomite, or dark-gray dolomite or limestone and tan, laminated, silty dolomite.
MUP_270
Tomstown Formation, Dargan Member
Ctb
_tb
Light-gray to white, massive to poorly bedded, highly fractured, sugary dolomite.
MUP_271
Tomstown Formation, Benevola Member
Ctf
_tf
Medium- to dark-gray, thick-bedded, mottled dolomite with white, void-filling, sparry dolomite.
MUP_272
Tomstown Formation, Fort Duncan Member
Ctbh
_tbh
Three stacked lithologies: basal - tan, vuggy dolomite (rarely exposed); middle - very light gray, sheared laminated dolomitic marble (Keedysville marble bed); upper - gray ribbony, burrow-mottled lime mudstone
MUP_273
Tomstown Formation, Bolivar Heights Member
MUP_274
MUP_275
MUP_276
MUP_277
MUP_278
MUP_279
MUP_280
MUP_281
MUP_282
MUP_283
MUP_284
MUP_285
MUP_286
MUP_287
MUP_288
MUP_289
Chm
_hm
Metasandstone (of mappable thickness), fine- to med-grained, highly argillaceous, dark green-gray; contains Skolithus burrows especially near top of Harpers Formation
MUP_290
Harpers Formation, metasandstone
MUP_291
MUP_292
MUP_293
MUP_294
MUP_295
MUP_296
MUP_297
Ca
_a
Three parts: lower - dk green-gray phyllitic shale and siltstone with white Skolithus-borrowed sandstone; middle - white, bioturbated and crossbedded sandstone; upper - gray, crossbedded, vuggy sandstone-conglomerate
MUP_298
Antietam Formation
MUP_299
MUP_300
MUP_301
MUP_302
MUP_303
MUP_304
MUP_305
MUP_306
MUP_307
MUP_308
MUP_309
MUP_310
MUP_311
MUP_312
MUP_313
MUP_314
MUP_315
MUP_316
MUP_317
Zcm
Medium to dark greenish-gray, chloritic, locally amygdaloidal, epidote-rich metabasalt.
MUP_318
Catoctin Formation, metabasalt
Zcr
Undifferentiated bluish-gray metarhyolite in which no single variety is dominant.
MUP_319
Catoctin Formation, metarhyolite
MUP_320
MUP_321
MUP_322
MUP_323
Zsrq
Very light gray, thin-bedded, laminated and cross-laminated sericitic quartzite that weathers light greenish-gray to light-gray; and medium light gray, thick-bedded, coarse-grained, laminated quartzite, weathering light-gray.
MUP_324
Swift Run Formation, quartzite
Ygl
Fine- to medium-grained, tan to very light gray, massive, finely banded to indistinctly foliated chlorite-quartz-microcline-plagioclase gneiss.
MUP_325
Basement gneiss complex, leucocratic gneiss
Zsrp
Very light gray, dusky yellow green and very light greenish-gray, lustrous quartz sericite(?) phyllite that weathers grayish-orange to very light gray.
MUP_326
Swift Run Formation, phyllite
MUP_327
MUP_328
MUP_329
Chma
_hma
Light-to medium-gray, coarse grained to conglomeratic, cross-bedded quartzite, commonly less than 30 feet (10 m) in thickness.
MUP_330
Harpers Formation, Mont Alto Member
MUP_331
MUP_332
Ygb
Fine- to medium-grained, very light gray to yellowish-gray granitic rock that weathers very pale orange, grayish-pink, and grayish-orange to pale brown.
MUP_333
Basement gneiss complex, biotite gneiss
Ygh
Biotite-hornblende-plagioclase gneiss, medium-grained, granular, massive or poorly foliated, weathers light olive-gray, pale olive, or greenish gray
MUP_334
Basement gneiss complex, hornblende gneiss
MUP_335
MUP_336
MUP_337
MUP_338
MUP_339
MUP_340
MUP_341
MUP_342
MUP_343
MUP_344
MUP_345
MUP_346
MUP_347
MUP_348
MUP_349
Zcd
Typically dark greenish-gray to grayish olive-green, fine- to medium-grained metadiabase or metabasalt.
MUP_350
Catoctin Formation, mafic dikes
MUP_351
MUP_352
Ygt
Fine- to medium-grained, very light gray, finely banded to indistinctly foliated quartz-microcline-plagioclase gneiss. Similar to leucocratic gneiss, but with scattered garnets. Weathers light-gray to yellowish.
MUP_353
Basement gneiss complex, garnet gneiss
MUP_354
MUP_355
MUP_356
MUP_357
MUP_358
MUP_359
MUP_360
MUP_361
MUP_362
MUP_363
MUP_364
MUP_365
MUP_366
MUP_367
MUP_368
MUP_369
MUP_370
MUP_371
MUP_372
MUP_373
MUP_374
MUP_375
MUP_376
MUP_377
MUP_378
MUP_379
MUP_380
MUP_381
MUP_382
MUP_383
MUP_384
MUP_385
MUP_386
MUP_387
MUP_388
MUP_389
MUP_390
MUP_391
MUP_392
MUP_393
MUP_394
MUP_395
MUP_396
MUP_397
MUP_398
MUP_399
MUP_400
MUP_401
MUP_402
MUP_403
MUP_404
MUP_405
MUP_406
MUP_407
MUP_408
MUP_409
MUP_410
MUP_411
Zcp1
Poorly exposed, lustrous, light-gray to medium dark gray, olive-gray phyllite, or mottled yellowish-gray and medium-gray phyllite.
MUP_412
Catoctin Formation, phyllite unit 1
MUP_413
MUP_414
Zcp2
Phyllite, greenish gray and very light gray; may be silicified; weathered surfaces commonly soft and soapy
MUP_415
Catoctin Formation, phyllite unit 2
MUP_416
MUP_417
MUP_418
MUP_419
MUP_420
MUP_421
MUP_422
MUP_423
Zcrf
Flow-banded, bluish-gray metarhyolite containing nearly planar, locally convoluted flow bands 0.12 to 0.4 inch (3 to 10 mm) thick.
MUP_424
Catoctin Formation, flow banded metarhyolite
Zcrp
Porphyritic, bluish-gray metarhyolite with conspicuous very light gray to very pale orange or pinkish-gray feldspar laths.
MUP_425
Catoctin Formation, porphyritic metarhyolite
MUP_426
MUP_427
MUP_428
MUP_429
MUP_430
MUP_431
MUP_432
MUP_433
MUP_434
MUP_435
MUP_436
MUP_437
MUP_438
MUP_439
MUP_440
MUP_441
MUP_442
MUP_443
MUP_444
Zcp3
Medium dark gray, medium bluish-gray, or light-gray phyllite containing blebs 2 to 4 mm long.
MUP_445
Catoctin Formation, phyllite unit 3
MUP_446
MUP_447
MUP_448
MUP_449
MUP_450
MUP_451
MUP_452
MUP_453
MUP_454
MUP_455
MUP_456
MUP_457
MUP_458
MUP_459
MUP_460
MUP_461
MUP_462
MUP_463
MUP_464
MUP_465
MUP_466
MUP_467
MUP_468
MUP_469
MUP_470
MUP_471
MUP_472
Zcmp
Metabasalt, greenish-gray to bluish-green rock that weathers bluish-gray to dark greenish-gray.
MUP_473
Catoctin Formation, porphyritic metabasalt
MUP_474
MUP_475
MUP_476
MUP_477
MUP_478
MUP_479
MUP_480
MUP_481
MUP_482
MUP_483
MUP_484
MUP_485
MUP_486
MUP_487
MUP_488
MUP_489
MUP_490
MUP_491
MUP_492
MUP_493
CZlc
_Zlc
Medium-bedded, medium light gray, grayish-yellow green or dusky blue conglomerate that weathers light-gray and greenish-gray or dusky blue.
MUP_494
Loudoun Formation, conglomerate
MUP_495
MUP_496
MUP_497
MUP_498
MUP_499
MUP_500
MUP_501
MUP_502
Biotite-hornblende-plagioclase gneiss; massive or pooly foliated
MUP_503
MUP_504
MUP_505
MUP_506
MUP_507
MUP_508
MUP_509
MUP_510
MUP_511
MUP_512
MUP_513
MUP_514
MUP_515
MUP_516
MUP_517
MUP_518
MUP_519
Zcdf
Massive, light-gray to medium-gray felsite; weathers light orange brown. Contains very few small feldspar phenocrysts.
MUP_520
Catoctin Formation, felsic dikes
MUP_521
MUP_523
MUP_524
MUP_525
MUP_526
MUP_527
MUP_528
MUP_529
MUP_530
MUP_531
MUP_532
MUP_533
MUP_534
MUP_535
MUP_536
MUP_537
MUP_538
MUP_539
MUP_540
MUP_541
MUP_542
MUP_543
MUP_544
MUP_545
MUP_546
MUP_547
MUP_548
MUP_549
MUP_550
MUP_551
MUP_552
MUP_553
MUP_554
MUP_555
MUP_556
MUP_557
MUP_558
MUP_559
MUP_560
MUP_561
MUP_562
MUP_563
MUP_564
MUP_565
MUP_566
MUP_567
MUP_568
MUP_569
MUP_570
MUP_571
MUP_572
MUP_573
MUP_574
MUP_575
MUP_576
MUP_577
MUP_578
MUP_579
MUP_580
MUP_581
MUP_582
MUP_583
MUP_584
MUP_585
MUP_586
MUP_587
MUP_588
MUP_589
MUP_590
MUP_591
MUP_592
MUP_593
MUP_594
MUP_595
MUP_596
Ygp
Fine- to medium-grained, tan to rusty red, highly foliated micaceous-quartz-garnet paragneiss to schist. Weathers to a yellowish-brown or very pale orange, schistose rock.
MUP_597
Basement gneiss complex, paragneiss
MUP_598
MUP_599
MUP_600
MUP_601
MUP_602
MUP_603
MUP_604
MUP_605
MUP_606
MUP_607
MUP_608
MUP_609
MUP_610
MUP_611
MUP_612
MUP_613
MUP_614
MUP_615
MUP_616
MUP_617
MUP_618
MUP_619
MUP_620
MUP_621
MUP_622
MUP_623
MUP_624
MUP_625
MUP_626
MUP_627
MUP_628
MUP_629
MUP_630
MUP_631
MUP_632
MUP_633
MUP_634
MUP_635
MUP_636
MUP_637
MUP_638
MUP_639
MUP_640
MUP_641
MUP_642
MUP_643
MUP_644
MUP_645
MUP_646
MUP_647
MUP_648
MUP_649
MUP_650
MUP_651
MUP_652
MUP_653
MUP_654
MUP_655
MUP_656
MUP_657
MUP_658
MUP_659
MUP_660
MUP_661
MUP_662
MUP_663
MUP_664
MUP_665
MUP_666
MUP_667
MUP_668
MUP_669
MUP_670
MUP_671
MUP_672
MUP_673
MUP_674
Zcrr
Grayish-red to dusky reddish-purple, porphyritic metarhyolite.
MUP_675
Catoctin Formation, red metarhyolite
MUP_676
MUP_677
MUP_678
MUP_679
MUP_680
MUP_681
MUP_682
MUP_683
MUP_684
Zcra
Aphanitic, bluish-gray metarhyolite that is massive and dense, and exhibits a conchoidal fracture.
MUP_685
Catoctin Formation, aphanitic metarhyolite
MUP_686
MUP_687
MUP_688
MUP_689
MUP_690
MUP_691
MUP_692
MUP_693
MUP_694
MUP_695
MUP_696
MUP_697
MUP_698
MUP_699
MUP_700
MUP_701
Zcrb
Dusky blue-gray, metarhyolite breccia with angular to subrounded clasts that weather to a lighter color than the felsic matrix.
MUP_702
Catoctin Formation, metarhyolite breccia
MUP_703
MUP_704
MUP_705
MUP_706
MUP_707
MUP_708
MUP_709
MUP_710
MUP_711
MUP_712
MUP_713
MUP_714
MUP_715
MUP_716
MUP_717
MUP_718
MUP_719
MUP_720
MUP_721
MUP_722
MUP_723
MUP_724
MUP_725
MUP_726
MUP_727
MUP_728
MUP_729
MUP_730
MUP_731
MUP_732
Zcpl
Pale purple to grayish red-purple or very light gray phyllite. Locally, color is mottled with red quartz grains and light-gray to yellowish-gray porphyroblasts of feldspar.
MUP_733
Catoctin Formation, lavender phyllite
MUP_734
MUP_735
MUP_736
MUP_737
MUP_738
MUP_739
MUP_740
MUP_741
MUP_742
MUP_743
MUP_744
MUP_745
MUP_746
MUP_747
MUP_748
MUP_749
MUP_750
MUP_751
MUP_752
MUP_753
MUP_754
MUP_755
MUP_756
MUP_757
MUP_758
MUP_759
MUP_760
MUP_761
MUP_762
MUP_763
MUP_764
MUP_765
MUP_766
MUP_767
MUP_768
MUP_769
MUP_770
MUP_771
MUP_772
MUP_773
MUP_774
MUP_775
MUP_776
MUP_777
MUP_778
MUP_779
MUP_780
MUP_781
MUP_782
MUP_783
MUP_784
MUP_785
MUP_786
MUP_787
MUP_788
MUP_789
MUP_790
Zcb
Dark greenish gray, locally phyllitic, chloritic, basalt.  Commonly has strongly developed cleavage.  These bodies are present in the basement gneiss complex and appear to represent dikes that once contacted the main Catoctin outcrop belt.
MUP_791
Catoctin Formation, basaltic dike
MUP_792
MUP_793
MUP_794
MUP_795
MUP_796
Zcp
Light-to medium-gray phyllite containing highly elongated light-gray flecks and blebs.
MUP_797
Catoctin Formation, phyllite
Ct
_t
Predominantly buff-weathering, medium- to dark-gray dolomite, dolomitic limestone, and limestone. Divided into 4 members
MUP_798
Tomstown Formation
MUP_799
Trl
^rl
Light-gray to light reddish-gray, very thickly bedded, boulder conglomerate. Clasts are mainly subangular to subrounded limestone and dolostone of Cambrian and Ordovician age, but locally Triassic age siltstone and sandstone are prevalent.
MUP_800
Leesburg Formation
MUP_801
MUP_802
MUP_803
MUP_804
MUP_805
MUP_806
MUP_807
MUP_808
MUP_809
MUP_810
Zsr
Medium gray brown, silty sandstone with intervals of very light gray, foliated, micaceous marble.
MUP_811
Swift Run Formation
Trb
^b
Brownish-red to reddish-brown, argillaceous, massive siltstone with thin, fine-grained sandstone interbeds.
MUP_812
Balls Bluff Siltstone
Trmps
^mps
Medium-grained sandstone beds exhibiting sharp, convex-down bases, shale-pebble lag conglomerates and fining upward character.
MUP_813
Manassas Formation, Poolesville Member, sandstone
Trmp
^mp
Reddish-brown to reddish-gray, locally greenish-gray, medium-grained sandstone and reddish, variegated claystone. Sandstone beds exhibit sharp, convex-down bases, shale-pebble lag conglomerates, and fining-upward character.
MUP_814
Manassas Formation, Poolesville Member
MUP_815
MUP_816
MUP_817
MUP_818
MUP_819
MUP_820
MUP_821
MUP_822
MUP_823
MUP_824
MUP_825
MUP_826
MUP_827
MUP_828
MUP_829
MUP_830
MUP_831
MUP_832
MUP_833
MUP_834
MUP_835
MUP_836
MUP_837
MUP_838
MUP_839
MUP_840
MUP_841
MUP_842
MUP_843
MUP_844
MUP_845
MUP_846
MUP_847
MUP_848
MUP_849
MUP_850
MUP_851
MUP_852
MUP_853
MUP_854
MUP_855
MUP_856
MUP_857
MUP_858
MUP_859
Three stacked lithologies: basal - tan, vuggy dolomite (rarely exposed); middle - very light gray, sheared laminated dolomitic marble (Keedysville marble bed); upper - gray, ribbony, burrow-mottled lime mudstone
MUP_860
MUP_861
MUP_862
MUP_863
MUP_864
MUP_865
Omu
Interbedded medium-gray shale and thin, light-gray to tan, silty sandstone at the base, grading upward into interbedded greenish-gray to medium-gray siltstone and silty shale with medium- to thick-bedded medium- to coarse-grained sandstone
MUP_866
Martinsburg Formation, upper member
MUP_867
MUP_868
MUP_869
MUP_870
MUP_871
MUP_872
MUP_873
MUP_874
MUP_875
MUP_876
MUP_877
MUP_878
MUP_879
MUP_880
MUP_881
MUP_882
MUP_883
MUP_884
MUP_885
MUP_886
MUP_887
MUP_888
MUP_889
MUP_890
MUP_891
MUP_892
MUP_893
MUP_894
MUP_895
MUP_896
MUP_897
MUP_898
MUP_899
MUP_900
MUP_901
MUP_902
MUP_903
MUP_904
MUP_905
MUP_906
MUP_907
MUP_908
MUP_909
MUP_910
MUP_911
MUP_912
MUP_913
MUP_914
MUP_915
MUP_916
MUP_917
MUP_918
MUP_919
MUP_920
MUP_921
MUP_922
MUP_923
MUP_924
MUP_925
MUP_926
MUP_927
MUP_928
MUP_929
MUP_930
MUP_931
MUP_932
MUP_933
MUP_934
MUP_935
MUP_936
MUP_937
MUP_938
MUP_939
MUP_940
MUP_941
MUP_942
MUP_943
CZschp
_Zschp
Bluish-purple, hematite-rich phyllite, resembles Ijamsville Phyllite (Southworth et. al, 2008).
MUP_944
Sams Creek Formation, hematite phyllite
MUP_945
MUP_946
MUP_947
MUP_948
MUP_949
MUP_950
MUP_951
MUP_952
MUP_953
MUP_954
MUP_955
MUP_956
MUP_957
MUP_958
MUP_959
MUP_960
MUP_961
MUP_962
MUP_963
MUP_964
MUP_965
MUP_966
MUP_967
MUP_968
MUP_969
MUP_970
MUP_971
MUP_972
MUP_973
MUP_974
MUP_975
MUP_976
MUP_977
MUP_978
MUP_979
MUP_980
MUP_981
MUP_982
MUP_983
MUP_984
MUP_985
MUP_986
MUP_987
MUP_988
MUP_989
MUP_990
MUP_991
CZim
_Zim
Light olive-gray, sandy limestone and dusky red, calcareous quartzite occurs within phyllite locally.
MUP_992
Ijamsville Phyllite, marble
MUP_993
MUP_994
MUP_995
MUP_996
MUP_997
MUP_998
MUP_999
MUP_1000
MUP_1001
MUP_1002
MUP_1003
MUP_1004
MUP_1005
MUP_1006
MUP_1007
MUP_1008
MUP_1009
MUP_1010
MUP_1011
MUP_1012
MUP_1013
MUP_1014
MUP_1015
MUP_1016
MUP_1017
CZscs
_Zscs
Metasiltstone, phyllite, quartzite, and metagraywacke, undifferentiated. Light-brown metasiltstone interbedded with quartzite and calcareous metasandstone. Bedding can be recognized except where transposed in shear zones adjacent to faults.
MUP_1018
Sams Creek Formation, metasiltstone
MUP_1019
MUP_1020
MUP_1021
MUP_1022
MUP_1023
MUP_1024
MUP_1025
MUP_1026
MUP_1027
MUP_1028
MUP_1029
MUP_1030
MUP_1031
MUP_1032
CZiq
Yellowish-gray, fine- to medium-grained, sericitic quartzite locally intervenes between phyllite and metabasalt.
MUP_1033
Ijamsville Phyllite, quartzite
MUP_1034
Cuq
_uq
Light olive-gray and light brownish-gray, coarse-grained, thin- to medium-bedded, cross-bedded, pitted, vuggy, friable, lensoidal, and discontinuous.
MUP_1035
Urbana Formation, quartzite
MUP_1036
MUP_1037
MUP_1038
MUP_1039
MUP_1040
MUP_1041
MUP_1042
MUP_1043
MUP_1044
MUP_1045
MUP_1046
MUP_1047
MUP_1048
MUP_1049
MUP_1050
MUP_1051
MUP_1052
MUP_1053
MUP_1054
MUP_1056
MUP_1057
MUP_1058
MUP_1059
MUP_1060
Cu
_u
Predominately moderate olive-brown to light olive-gray, calcareous metagraywacke and metasiltstone.
MUP_1061
Urbana Formation
MUP_1062
MUP_1063
MUP_1064
MUP_1065
MUP_1066
MUP_1067
MUP_1068
MUP_1069
MUP_1070
MUP_1071
MUP_1072
MUP_1073
MUP_1074
MUP_1075
MUP_1076
MUP_1077
MUP_1078
MUP_1079
MUP_1080
MUP_1081
MUP_1082
MUP_1083
MUP_1084
MUP_1085
MUP_1086
MUP_1087
MUP_1088
MUP_1089
MUP_1090
Trn
^n
Brownish-red to dark reddish-brown, argillaceous to silty sandstone and micaceous siltstone with subordinate interbedded silty shale and mudstone.
MUP_1091
New Oxford Formation
MUP_1092
MUP_1093
MUP_1094
MUP_1095
MUP_1096
MUP_1097
MUP_1098
MUP_1099
MUP_1100
MUP_1101
MUP_1102
MUP_1103
MUP_1104
MUP_1105
MUP_1106
MUP_1107
MUP_1108
MUP_1109
MUP_1110
MUP_1111
MUP_1112
MUP_1113
MUP_1114
MUP_1115
MUP_1116
MUP_1117
MUP_1118
MUP_1119
MUP_1120
MUP_1121
MUP_1122
MUP_1123
MUP_1124
MUP_1125
MUP_1126
MUP_1127
MUP_1128
MUP_1129
MUP_1130
MUP_1131
MUP_1132
MUP_1133
Trmt
^mt
Light-gray to light reddish-gray, subangular to subrounded, limestone and dolomite conglomerate. Clasts are predominately tan dolostone, but locally reddish-siltstone, sandstone, and some limestone clasts are prevalent.
MUP_1134
Manassas Formation, Tuscarora Creek Member
MUP_1135
MUP_1136
MUP_1137
MUP_1138
MUP_1139
MUP_1140
MUP_1141
MUP_1142
MUP_1143
MUP_1144
MUP_1145
MUP_1146
MUP_1147
MUP_1148
MUP_1149
MUP_1150
MUP_1151
MUP_1152
MUP_1153
MUP_1154
MUP_1155
MUP_1156
MUP_1157
MUP_1158
MUP_1159
MUP_1160
MUP_1161
MUP_1162
MUP_1163
MUP_1164
MUP_1165
MUP_1166
MUP_1167
MUP_1168
MUP_1169
MUP_1170
MUP_1171
MUP_1172
MUP_1173
MUP_1174
MUP_1175
MUP_1176
MUP_1177
MUP_1179
MUP_1180
MUP_1181
MUP_1182
MUP_1183
MUP_1184
MUP_1185
MUP_1186
MUP_1187
MUP_1188
MUP_1189
MUP_1190
MUP_1191
MUP_1192
MUP_1193
MUP_1194
MUP_1195
MUP_1196
MUP_1197
CZscl
_Zscl
Light-gray, thinly layered, argillaceous metalimestone (Southworth et. al, 2008).
MUP_1198
Sams Creek Formation, metalimestone
MUP_1199
MUP_1200
MUP_1201
MUP_1202
MUP_1203
MUP_1204
MUP_1205
MUP_1206
MUP_1207
MUP_1208
MUP_1209
MUP_1210
MUP_1211
MUP_1212
MUP_1213
MUP_1214
MUP_1215
MUP_1216
MUP_1217
MUP_1218
MUP_1219
MUP_1220
MUP_1221
MUP_1222
MUP_1223
MUP_1224
MUP_1225
MUP_1226
MUP_1227
MUP_1228
MUP_1229
MUP_1230
MUP_1231
MUP_1232
MUP_1233
MUP_1234
MUP_1235
MUP_1236
MUP_1237
MUP_1238
MUP_1239
MUP_1240
MUP_1241
MUP_1242
MUP_1243
MUP_1244
MUP_1245
MUP_1246
MUP_1247
MUP_1248
MUP_1249
MUP_1250
MUP_1251
MUP_1252
MUP_1253
MUP_1254
MUP_1255
MUP_1256
MUP_1257
CZmbq
_Zmbq
Tan to reddish quartzite. Beds of quartzite 15 to 60 cm thick (6 to 24 inches) interbedded with muscovite and chlorite phyllites. Very resistant to weathering.
MUP_1258
Marburg Formation, quartzite
MUP_1259
MUP_1260
MUP_1261
MUP_1262
MUP_1263
MUP_1264
MUP_1265
MUP_1266
MUP_1267
MUP_1268
MUP_1269
MUP_1270
MUP_1271
MUP_1272
MUP_1273
MUP_1274
MUP_1275
MUP_1276
MUP_1277
MUP_1278
MUP_1279
MUP_1280
MUP_1281
MUP_1282
MUP_1283
MUP_1284
MUP_1285
MUP_1286
MUP_1287
MUP_1288
MUP_1289
MUP_1290
MUP_1291
MUP_1292
MUP_1293
MUP_1294
MUP_1295
MUP_1296
MUP_1297
MUP_1298
MUP_1299
MUP_1300
MUP_1301
MUP_1302
MUP_1303
MUP_1304
MUP_1305
MUP_1306
MUP_1307
MUP_1308
MUP_1309
MUP_1310
MUP_1311
MUP_1312
MUP_1313
MUP_1314
MUP_1315
MUP_1316
MUP_1317
MUP_1318
MUP_1319
MUP_1320
MUP_1321
MUP_1322
MUP_1323
MUP_1324
MUP_1325
MUP_1326
MUP_1327
MUP_1328
MUP_1329
MUP_1330
MUP_1331
MUP_1332
MUP_1333
MUP_1334
MUP_1335
MUP_1336
MUP_1337
MUP_1338
MUP_1339
MUP_1340
MUP_1341
MUP_1342
MUP_1343
MUP_1344
MUP_1345
MUP_1346
MUP_1347
MUP_1348
MUP_1349
MUP_1350
MUP_1351
MUP_1352
MUP_1353
MUP_1354
MUP_1355
MUP_1356
MUP_1357
MUP_1358
MUP_1359
MUP_1360
MUP_1361
MUP_1362
MUP_1363
MUP_1364
MUP_1365
MUP_1366
MUP_1367
MUP_1368
MUP_1369
MUP_1370
MUP_1371
MUP_1372
MUP_1373
MUP_1374
MUP_1375
MUP_1376
_Ziq
MUP_1377
MUP_1378
MUP_1379
MUP_1380
MUP_1381
MUP_1382
MUP_1383
MUP_1384
MUP_1385
MUP_1386
MUP_1388
MUP_1389
MUP_1390
MUP_1391
MUP_1392
MUP_1393
MUP_1394
MUP_1395
MUP_1396
MUP_1398
MUP_1399
MUP_1400
MUP_1401
MUP_1402
MUP_1403
MUP_1404
MUP_1405
MUP_1406
MUP_1407
MUP_1408
MUP_1409
MUP_1410
MUP_1411
MUP_1412
MUP_1413
MUP_1414
MUP_1415
MUP_1416
MUP_1417
MUP_1418
MUP_1420
CZib
_Zib
Dark-green and schistose metabasalt composed of chlorite, epidote, and quartz.
MUP_1421
Ijamsville Phyllite, metabasalt
MUP_1422
MUP_1423
MUP_1424
MUP_1425
MUP_1426
MUP_1427
MUP_1428
MUP_1429
MUP_1430
MUP_1431
MUP_1432
MUP_1433
MUP_1434
MUP_1435
MUP_1436
MUP_1437
MUP_1438
MUP_1439
MUP_1440
MUP_1441
MUP_1442
MUP_1443
MUP_1444
MUP_1445
MUP_1446
MUP_1447
MUP_1448
MUP_1449
MUP_1450
MUP_1451
MUP_1452
MUP_1453
MUP_1454
MUP_1455
MUP_1456
MUP_1457
CZil
_Zil
Light bluish-gray to medium light gray, thin-bedded, laminated, carbonaceous and argillaceous metalimestone; and minor, medium dark gray, finely laminated, carbonaceous phyllite.
MUP_1458
Ijamsville Phyllite, metalimestone
MUP_1459
MUP_1460
MUP_1461
MUP_1462
MUP_1463
MUP_1464
MUP_1465
MUP_1466
MUP_1467
MUP_1468
Dhbs
A suite of gray to reddish-brown thinly laminated and-or interbedded shales, siltstones, and sandstones.
MUP_1469
Harrell-Brallier-Scherr Formations (undivided)
Df
Interbedded, olive-gray medium- to coarse-grained, cross-bedded sandstone and greenish-gray to dusky-red, fossiliferous shale and siltstone.
MUP_1470
Foreknobs Formation
MUP_1471
Dh
Interbedded, reddish-brown to brownish-red, locally greenish-gray sandstone, reddish-brown siltstone, shale, and rooted claystone.
MUP_1472
Hampshire Formation
Mp
Light-gray, tan and reddish-brown, coarse-grained to conglomeratic, thick-bedded to cross-bedded sandstone and thin beds of gray shale and coaly shale.
MUP_1473
Purslane Formation
MDr
Interbedded, gray silty shale, light-gray to tan sandstone, and coaly and reddish-shale.
MUP_1474
Rockwell Formation
MUP_1475
MUP_1476
MUP_1477
Dm
Medium-gray to olive-gray massive siltstone to fine-grained sandstone occurs near the base and top of the formation and is interbedded with siltstone, sandstone, with silty, hackly shale.
MUP_1478
Mahantango Formation
Dnm
Medium to dark brownish-gray to medium dark gray, calcareous, fossiliferous shale, with thin (30 cm) beds of dark-gray, argillaceous limestone.
MUP_1479
Needmore-Marcellus Shales
Do
Interbedded, medium- to dark-gray, siliceous shale and sandy and cherty limestone, overlain by tan, fine-grained, calcareous sandstone, and then by light-gray, medium- to coarse-grained, thin- to thick-bedded, calcareous sandstone.
MUP_1480
Oriskany Sandstone
DSkh
Light to medium gray, medium to thickly bedded, crystalline to cherty, crinoidal limestone.
MUP_1481
Keyser-Helderberg Formations (undivided)
Sto
Medium to light gray, fine-grained, thinly laminated, mudcracked, dolomitic limestone with thin layers of medium gray, fine-grained limestone, and tan laminated dolomite.
MUP_1482
Tonoloway Formation
Sm
Interbedded, greenish-gray, calcareous shale and medium- to dark-gray, thinly bedded, fossiliferous limestone.
MUP_1483
McKenzie Formation
Sb
Interbedded, reddish-gray to brownish-gray, fine-grained sandstone and hackly shale to mudrock.
MUP_1484
Bloomsburg Formation
MUP_1485
MUP_1486
MUP_1487
MUP_1488
Srh
Light olive to pale reddish gray, light gray, greenish gray, and deep purple shale, brownish red sandstone, and thin reddish siltstone.  The Rose Hill Formation is mostly fissile, papery shale, weathering to rusty chips.
MUP_1489
Rose Hill Formation
Sk
Light gray to yellowish gray, fine- to medium-grained sandstone.  The unit is thin-bedded in the lower part and thick-bedded in the middle and upper part. The Keefer Sandstone is resistant to weathering and tends to form a prominent topographic ridge.
MUP_1490
Keefer Sandstone
MUP_1491
MUP_1492
MUP_1493
MUP_1494
MUP_1495
MUP_1496
MUP_1497
MUP_1498
MUP_1499
MUP_1500
MUP_1501
MUP_1502
MUP_1503
MUP_1504
Swc
Interbedded, greenish gray to light gray, calcareous shale, and tan, dolomitic shale containing mud cracks, laminations, and salt and gypsum casts.
MUP_1505
Wills Creek Formation
MUP_1506
MUP_1507
MUP_1508
MUP_1509
MUP_1510
MUP_1511
MUP_1512
MUP_1513
MUP_1514
MUP_1515
MUP_1516
MUP_1517
MUP_1518
MUP_1519
MUP_1520
MUP_1521
MUP_1522
MUP_1523
Om
Medium to dark gray, fissile shale at the base, overlain by, medium gray, silty shale and thinly interbedded medium-grained sandstone, and then by thick-bedded, medium-grained, fining upward sandstone at the top of the formation.
MUP_1524
Martinsburg Shale
MUP_1525
MUP_1526
MUP_1527
MUP_1528
MUP_1529
MUP_1530
MUP_1531
MUP_1532
St
Light-gray, fine- to medium-grained, medium-bedded, dense sandstone.  Locally sandstone layers are interbedded with thin gray shale. The Tuscarora is a competent ridge-maker.
MUP_1533
Tuscarora Sandstone
MUP_1534
MUP_1535
MUP_1536
MUP_1537
MUP_1538
MUP_1539
MUP_1540
MUP_1541
MUP_1542
MUP_1543
MUP_1544
MUP_1545
MUP_1546
MUP_1547
MUP_1548
MUP_1549
MUP_1550
MUP_1551
MUP_1552
MUP_1553
MUP_1554
MUP_1555
MUP_1556
Medium grayish green to gray, calcareous shale, and interbedded argillaceous, gray limestone.   The McKenzie Formation is largely shale, mostly calcareous, fissile to lumpy or hackly in places, finely laminated in part.
MUP_1557
MUP_1558
MUP_1559
MUP_1560
MUP_1561
MUP_1562
MUP_1563
MUP_1564
MUP_1565
MUP_1566
MUP_1567
MUP_1568
MUP_1569
MUP_1570
MUP_1571
MUP_1572
MUP_1573
MUP_1574
MUP_1575
MUP_1576
MUP_1577
MUP_1578
MUP_1579
MUP_1580
MUP_1581
MUP_1582
MUP_1583
MUP_1584
MUP_1585
Csq
_sq
Pinkish-gray to white, fine-to medium-grained granular quartzite. Medium-bedded to massive, well-sorted, graded, cross-bedded and ripple marked.
MUP_1586
Sugarloaf Mountain Quartzite
MUP_1587
MUP_1588
MUP_1589
MUP_1590
MUP_1591
MUP_1592
MUP_1593
MUP_1594
MUP_1595
MUP_1596
MUP_1597
MUP_1598
MUP_1599
MUP_1600
Oj
Interbedded, reddish-brown to brownish-red, fine- to medium-grained, medium- to thick-bedded, cross-bedded sandstone and micaceous siltstone and silty shale.
MUP_1601
Juniata Formation
MUP_1602
MUP_1603
MUP_1604
MUP_1605
MUP_1606
MUP_1607
JTrtm
J^tm
Medium- to olive-gray, hard, brittle, and fractured hornfels and meta-arkose, adjacent to diabase intrusions.
MUP_1608
Thermally metamorphosed rocks
MUP_1609
MUP_1610
MUP_1611
MUP_1612
MUP_1613
MUP_1614
MUP_1615
MUP_1616
MUP_1617
MUP_1618
MUP_1619
MUP_1620
MUP_1621
MUP_1622
MUP_1623
MUP_1624
MUP_1625
MUP_1626
MUP_1627
MUP_1628
MUP_1629
MUP_1630
MUP_1631
MUP_1632
MUP_1633
MUP_1634
MUP_1635
Trgh
^rgh
Interbedded gray calcareous siltstone and shale; laminated, mudcracked, and brecciated limestone; and dark grayish-brown to reddish-brown siltstone and shale.
MUP_1636
Gettysburg Formation, Heidlersburg Member
MUP_1637
MUP_1638
MUP_1639
MUP_1640
MUP_1641
MUP_1642
MUP_1643
MUP_1644
MUP_1645
MUP_1649
MUP_1650
MUP_1651
MUP_1653
MUP_1654
MUP_1655
MUP_1656
MUP_1657
MUP_1658
MUP_1659
MUP_1660
MUP_1661
MUP_1662
MUP_1663
MUP_1664
MUP_1665
MUP_1666
MUP_1667
MUP_1668
MUP_1669
MUP_1670
MUP_1671
MUP_1672
MUP_1673
MUP_1674
MUP_1675
MUP_1676
MUP_1677
MUP_1678
MUP_1679
MUP_1680
MUP_1681
MUP_1682
MUP_1683
MUP_1684
MUP_1685
MUP_1686
MUP_1687
MUP_1688
MUP_1689
CZmb
_Zmb
Buff to light olive green quartz-muscovite phyllite with subordinate silvery gray quartz-paragonite-muscovite-chlorite phyllite and muscovite-quartz phyllite.
MUP_1690
Marburg Formation
MUP_1691