
Appendix C: Paleozoic Stratigraphic Units and Descriptions Ma Period Grp Forma-on Member Thick Descripon Paleoenvrionment Upper Contact Forms the uppermost cliffs and slopey ledges. Eastward-thinning, alternang red Lateral, eastward progression from open marine condiCons to 251 The Triassic Moenkopi Fm overlies the Kaibab in N. AZ and UT, Harrisburg 300-80 and yellow mudstone, thin bedded red sandstone, laminated aphaniCc limestone shallow, restricted-circulaon shoreline. Fossils: bryozoans, clams, but not at the Grand Canyon. Kaibab Fm and dolomite beds, and white gypsum deposits. cephalopods, gastropods, trilobites, corals, brachs, sponges, Fossil Mtn 300-250 An eastward-thinning gray, fossiliferous, medium-bedded, cherty limestone cliff. annelid worms, urchins, and crinoids. Conformable; white/tan/red chert nodules or beds marks it. Vegetated slope of red and white fg sandstone and siltstone with limestone beds Shoreline facies of cyclical marine incursions from the west. Locally disconformable but largely conformable. Contact is Woods Ranch 180 <6in thick and interbedded gypsum, eastward transiCon to x-bed sandstone. Contains one marine bivalve-bearing bed. between W.R. gypsum or ss and Kaibab cherty limestone or ss Similar environment, western open marine fossils: brachs, Cliff-forming, medium grained, gray fossiliferous limestone cliff, transiConing Toroweap Fm Brady Cyn 280-0 bryozoans, crinoids, and horn corals. Eastern interCdal fauna: Gradaonal upper contact eastward to fg dolomite. Westward thickening proporConal to Woods Ranch Mbr. bivalves, gastropods, few scaphopods and cephalopods. Red and yellow fine grained sandstone grading up a into silty sandstone and Seligman < 45 1 Shoreline facies of cyclical marine incursions from the west. Gradaonal upper contact mudstone slope, which is vegetated. with interbedded carbonates and gypsum. Westward thinning, but laterally variable thickness, white to tan, fine grained, well Locally unconformable with Toroweap Fm, planar truncaon Vast Coconino desert spread from AZ to Canada - wind transport Permian sorted, rounded, cross strafied, cliff forming quartz sandstone with minor K of underlying cross strafied beds, but in places interfingering 0-600 direct was north to south. It preserved tracks of mammal-like Coconino Ss feldspar. It has large-scale dune features, such as high-angle sets of planar tabular with the Toroweap. Conformable with Kaibab Ls in eastern repCles, scorpions, spiders, millipedes. and planar wedge cross straficaon and small scale ripple features as well localiCes where Toroweap is absent. The westward thickening, slope-forming Hermit Fm contains alternang light red Lowland river floodplain system with land plant fossils, possible A sharp disconformable break to the Coconino Ss (or 900-100 silty sandstone with dark red sandy mudstone. Thin bedded, cross amphibian trackways, and fronds and stems of seed ferns, pines, Hermit Fm Toroweap Formaon where Coconinio is absent). laminated/strafied in places. Local carbonate-pebble conglomerate lenses. and gingkos. Fine grained, cross strafied sandstone forms a massive cliff except where Pakoon ClasCc deposiCon similar to the Manakacha Fm. Evaporites likely limestone intertongues. The base alternates reddish sandstone and siltstone. Main Unconformable with the Hermit Shale, and has deep (>451) 1350-950 formed in either coastal or conCnental sabkha environments. Non- Esplanade Ss cliff is thick bedded, cross strafied, well-sorted quartz sand. Upper 2001 is a red, erosional channels scoured into it. marine arenaceous limestones in aeolian envs. 299 gypsiferous shale slope capped with red and white fine grained sandstone cliff. 299 Red, cross bedded, calcareous dolomiCc sandstone. The upper half is red shale Well-developed erosional upper contact is carved with Wescogame Fm 200-100 slopes and ss cliffs. Lower half is a prominent ss cliff. It preserves an E to W Likely similar environments to the Manakacha Fm. channels 50 1 deep filled with limestone-pebble gradaon from redbeds to sandstone and red mudstone to sandy limestone. conglomerate. Is likely the actual Penn-Permian unconformity. Westward thinning series of ledges and slopes of thin to thick-bedded, cross- Cross-strafied sandstone units are aeolian. Redbeds, laminated The upper erosional contact is unconformable and o1en Supai Group Manakacha Fm 150-300 strafied, fine grained, reddish sandstone with micriCc limestone and calcareous sandston, and bioturbated sandstones have unclear non-aeolian obscured by debris. A gap of Middle Penn. Cme is marked by shale components. origins. Limestones from low-energy open marine sengs. erosional, conglomerac channels with up to 50 1 relief. Light gray, thick bedded, fine grained to ooliCc, cliff-forming limestone and The clasCc sediments interbedded with shallow marine limestone Pennsylvanian Likely conformable, defined by a zone of gray, jasper-bearing 300-100 dolomite with lenses of red chert. Limestone beds are separated by thin, reddish probably represent a low coastal environment beginning in mid- Watahomigi Fm limestone, bright orange sandstone, and red mudstone. 318 purple, slope-forming siltstones and mudstones. Penn Cme. Diverse brachiopod fauna preserved. 318 Westward-draining river system turned to estuaries flooded by Terrestrial conglomerates and fossiliferous marine limestone and siltstone filling in Fossil biomarkers indicate an unconformity between Miss. transgressing sea. >60 fossil spp: brachs, gastropods, clams, corals, up to 300 a series of paleochannels carved into the then-exposed upper Redwall limestone, and Penn. strata. Talus o1en obscures the contact, but in Surprise Cyn Fm bryozoans, crinoids, stromatolites, trilobites, bones, teeth, terr. averaging 10001 wide and nearly 300 feet deep. places a low angle unconformity is recognizable. plants, microfossils. Westward thickening, thin bedded, fine grained, light gray limestone beds that Rare spiriferid brachiopods, bivalves, and corals, as well as 16 Upper Redwall Ls is heavily eroded and carved by Horseshoe Mesa 125-45 form receding ledges. species of foraminifera preserved in this regressive deposit. paleochannels, where the Surprise Canyon fills in. Main secCon of Redwall Limestone. Thick bedded, nearly pure limestone with local 2nd Redwall transgression. Invertebrates: solitary and colonial Mooney Falls 400-200 Conformable and difficult to idenCfy. dolomiCzaon and thin zones of chert lenses in upper porCon corals, spiriferid brachiopods, crinoids, and microfossils. Very diverse and abundant life in a regressing sea, especially Mississippian Redwall Ls Westward thickening, alternang light and dark beds of carbonate and chert. The Unconformable with Mooney Falls Member. Generally a Thunder Springs 150-100 preserved in the chert beds. Fossils: corals, bryozoans, carbonate is thin bedded limestone to the west, dolomite to the east. disconformity with local low-angle unconformiCes. cephalopods, gastropods, brachiopods, and crinoids. Westward thickening, light gray, thick-bedded, fine grained limestone in the west, Eastward transgressing shallow sea. Few, poorly preserved fossils Conformable, but recognizable but chert beds in the lower Whitmore Wash 200-100 but dolomite in central and eastern Grand Canyon. A pure carbonate lithology with of brachiopods, corals, and crinoids. Thunder Springs Member. 359 virtually no siliciclasCcs, it forms a resistant cliff. 359 Westward thickening, moderately thick, irregular beds of olive-gray, medmium Likely represents a very shallow marine basin to the west and Clear, unconformable upper boundary. It is characterized by a Devonian Temple Buke Fm 450-0 grained dolomite and quartz-dolomite sandstone. Sugary texture on weathered super-Cdal/estuarine condiCons eastward. Rare fossils (fish, disCnct transiCon in lithology to Redwall limestone and an 416 surfaces, forms a series of ledges and steep slopes. stromatolites, conodonts). irregular erosoinal surface with 5 to 20 feet of relief. 488 Westward thickening, gray, irregular, thin-bedded, very fine grained, dolomiCc A disconformity marked by 15-30 1 thick erosional channels limestone beds weather to dark gray at the surface and form sheer cliffs. Thin beds Trace fossils present; Rare fragments of sponges, molluscs, filled with Devonian sediment. Probably represents Cme lost 1400-650 Muav Ls and lenses of flat pebble conglomerates are locally present. Tongues of Bright echinoderms, and algae. from the Late Cambrian, Ordovician, Silurian, to the mid Angel Shale form slopes within the limestone cliffs. Devonian. Westward thickening, green, fine grained, glauconiCc, fissile shale interbedded Represents an offshore marine environment in the Tonto Sea The upper contact with the Muav limestone is fairly arbitrary Bright Angel Shl 450-270 with medium grained red-brown sandstone. Rust colored dolomite tongues form (<1001 deep). 47 spp trilobites, trace fossils, and brachiopods, because of the interfingering of the units – it changes with Cambrian occasional ledges in the otherwise slope-forming shale. with rare fragments of sponges, molluscs, echinoderms, and algae. locaon in the canyon. Tonto Group Westward thinning, sheer to ledgy, gray-brown to red-brown cliff-forming ss. Upper contact is transiConal rather than abrupt. In places, Beach to interCdal shoreline environments. Trace fossils can be 150-250 Coarse-grained with minor conglomerate lenses. Locally cemented with silica to Bright Angel Shale is interbedded with Tapeats ss. There, the Tapeats Ss common. Rare body fossils. 542 form quarCte-like areas. Small-scale cross bedding is common. upper contact is defined as the highest occurrence of Tapeats..
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