Geologic Studies in Alaska by the U.S. Geological Survey, 1992

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Table 1. Locality register for key conodonts and lithologic features-Continued MAP NO. vm 16 (A) 17 (A) 18 (A) 19 (RB) 20 (RB) 21 (RB) FIELD NO. (USGS COLLN. NO.) 91TR23A (3 1720-PC) 90AD60 91TR39 (3 1722-PC) 91ADlIA (3 1745-PC) 91ADI 1G (3 1746-PC) 90AD6 1 Z (30939-PC) 9 1 AD2B (3 1740-PC) 91AD6F (3 1741-PC) 9 1 AD6U (3 1742-PC) LATlTLTDE NJ LONGITUDE W. 68"36'1 O"1 157O29'35" 68"34'00"1 157"32'50n 68"33'32"/ 157"25'49" 68"35'55"/ 157"41'00" 68"33'58"/ 157"35'1OU 68"32'03"/ 157"34'15" 68"32'OOv/ 157"34'55" KEY CONODONT SPECIES AND LITHOLOGIES Calcitized radiolarite, barite, and minor black chert Bispathodus aff. B. urahensis fragments cavusgnathid fragment (fig. 77) Geniculatus? n. sp. transitional to Embsaygnathus sp. (fig. 7 U-W) Geniculatus aff. G. glottoides (fig. 7R, S) Radiolarian chert Calcitized radiolarite with barite. "Hindeodella " segaformis s.f. (fig. 7 0-0 Scaliognathus sp. indet. fragments (fig. 7N) Calcareous turbidites and lesser spiculitic mudstone Gnathodus aff. G. typicus "Hindeodella" segaformis s.f. Polygnathus communis Vogelgnathus? sp. REDEPOSITED LATE KINDERHOOKIAN FORMS: Siphonodella aff. S. crenulata Siphonodella spp. indet. Polygnathus communis REDEPOSITED CONODONTS OF KINDERHOOKIAN AGE: Siphonodella sp. (fig. 9Z) Spiculitic mudstone and lesser calcareous turbidites Gnurhodus cuneiformis Hindeodus crussidentatus Syncladognarhus geminus (fig. 9U) REDEPOSlTED KINDERHOOKIAN FORMS: Siphonodella sp. (fig. 9 Y) Spiculitic mudstone and lesser calcareous turbidites Dollymae hassi (fig. 9V) Gnathodus cuneiformis Kladognathus sp. Spiculitic mudstone and lesser calcareous turbidites Bispathodus utahensis Gnathodus aff. G. semiglaber "Hindeodella" segaformis s.f. REDEPOSITED KINDERHOOKIAN FORMS: Siphonodella sp. (fig. 9N) Bispathodus utahensis "Hindeodella " segaformis s.f. (fig. 9M) FOSSIL AGE AND CAI middle Mississippian (latest Osagean to Meramecian, probably middle Meramecian) CAI= 1.5-2 late Early Mississippian (Osagean, Upper typicus Zone through most of anchoralis-latus Zone No older than late Early Mississippian (no older than middle Osagean) CA1=2-2.5 No older than late Early Mississippian (no older than early Osagean) CAI=3-3.5 late Early Mississippian (lower 213 of Osagean-- typicus Zone-most of anchoralis -1atus Zone CAI=1.5 No older than late Early Mississippian (no older than middle Osagean) CAT=1.5-2 late Early Mississippian (middle Osagean) CAI= 1.5-2 REMARKS From the Stack barite deposit. The conodont faunule indicates postmortem hydraulic mixing of chiefly shallow-water biofacies with some deeper water biofacies. Nearly all conodonts are fragmentary and are probably part of a gravity-flow deposit. Representatives of Geniculatus glottoides and Embsaygnathus spp. are virtually unknown beyond England and Ireland. From 70-meter-thick measured section 0.8 km east of the Abby Creek barite deposit. Conodont faunule is from a baritic limestone bed 34 m above base of section. From 80-meter-thick section of the Rim Butte unit. 91ADI I A: 70 m above base of section; 22-centimeter graded carbonate bed. Conodonts are all small and represent a postmortem winnow. 91 AD I 1G: 80 m above base of section: crinoid-rich, coarse-grained skeletal packstone in bed -10 cm thick. All specimens are small and many are incomplete bar fragments indicating a postmortem winnow. The sample is from a fine-grained, locally silicified limestone bed that is 20 cm thick and contains parallel laminae. A few specimens have a surficial gray patina suggesting rapid heating-the sample is from 5 m above a mafic sill. From top of the Rim Butte unit, about 0.25 m below contact with overlying Imnaitchiak Chert. Conodont sample from fine-grained bioclastic packstone turbidite. Conodonts represent postmortem transport within the gnathodid biofacies. From section 67 m thick within the Rim Butte unit. 91AD6F: 5.5 m above base of section and about 0.5 m above mafic sill. From crossbedded silty limestone grading upward into micrite. 91AD6U: 61 m above base of section. From calcitized spiculite about 10 cm thick.
Table 1. Locality register for key conodonts and lithologic features-Continued MAP NO. WNm 22 (RB) 23 (RB) 24 (RB) 25 (RB) / FIELD NO. (USGS COLLN. NO.) 90AD64F (30940-PC) 90AD66A (30943-PC) 90AD67G (30944-PC) 90AD68 90AD52 91JS35D LATITLDE NJ LONGITUDE W. 68"32'58"/ 157"29'10M 68"33'00"1 157"29'30N 68"32'55"/ 157"30'20M 68"33'03"1 157"30'09" 68"33'5SU/ 157" 18'35" 68"21'35"/ / 158"08'45" 26 (RB) I 90AMu81 1 68"24'25"/ KEY CONODONT SPECIES AND LTTHOLOGE.5 Calcareous turbidites and lesser spiculitic mudstone Bisparhodus utuhensis Cavusgnathus unicornis (fig. 9A ) Gnurhodrrs pseudosemiglaber (fig. 98) REDEPOSITED OSAGEAN FORMS: Bactrognathus sp. indet. Doliognathus kurus (fig. 9C) "Hindeodella " segaformis s.f. Polv~nuth~ts , communis Pseutfopolygnathus pinnatus (fig. 9D) Pseudopolygnathus oxypageus REDEPOSITED LATE K~NDERHOOKIAN FORMS: Gnathodus punctatus (fig. 9 E) Siphonodella crenulata S. isostichtr-S. obsoleta (fig. 9F) Radiolarian chert Calcareous turbidites and spiculitic limestone Bispathodus utahensis (fig. 90) Dollymae hassi (fig. 9P) Gnathodus cuneiformis (fig. 9R) Kladognathus sp. Polygnathus communis Pseudopolygnathus multistriatus Ps. oxypageus (fig. 9Q) Ps. triangulus REDEPOSITED LATE KINDERHOOKTAN FORMS: Gnarhodus punctatus (fig. 9s) Siphonodella obsoleta (fig. 97) FOSSIL AGE AND CAI No older than early Late Mississippian (no older than late Meramecian) and containing redeposited conodonts of late Kinderhookian and Osagean age CAk3.5 REMARKS Calcareous turbidites and lesser spiculitic mudstone No older than late Early Conodont sample from partly silicified, fine-grained, Bispathotflts utuhensis (fig. 9M Mississippian (no older than bioclastic packstone 16.5 m below mafic sill. Clydagnathus aff. C. cav~tsformis (fig. 9G) middle Osagean, middle Conodonts represent a postmortem winnow--most Gnarhodus aff. G. pseudosemiglaber anchoralis-lcrtus Zone) specimens are small and incomplete. "Hintleodelltr " seguformis sf. (fig. 9 1) REDEPOSITED LATE KlNDERHOOKlAN FORMS: Siphonodella sp. (fig. 9L) CAIz2.5-3 Black shale and lesser calcareous turbidites with late Early Mississippian Conodont sample from fining upward bioclastic well-developed flute casts (early Osagean, typicus Zone packstone interlayered with spiculite; bed 4 cm thick. Bisparhodus utahensis CAT= 3 to 4; about 25% of the Nearly all specimens are broken and have a broad size Gnarhodus prtnctatus (fig. 9X) specimens have a surficial range indicating a graded deposit. Polygnathus communis gray patina suggesting Polygnathus inor~~atus (fig. 9 W) nearby - hydrothermal . and (or) Scaliognathus? sp. indet. fragments I igneous activity. Calcareous turbidites and lesser spiculitic mudstone / No older than late Early I Conodont sample from fine-grained bioclastic Bisparhodus utahensis Mississippian (no older than packstone 15 cm thick. ~oiodonts represent a "Hindeodella " segujormis s.f. middle Osagean) postmortem distal winnow composed of small, mostly REDEPOSITED KINDERHOOKIAN FORMS: CAI=2 broken delicate bar fragments and complete juvenile Siphonodella sp. Soiculitic mudstone and lesser calcareous turbidites 1 Calcareous turbidites and spiculitic mudstone elements. No older than late Early Mississippian (middle Osagean, Upper typicus Subzone to lower anchoralis- latus Zone) CAI=I-1.5 Conodont sample from graded bioclastic packstone. Mafic sill at least 7 m thick occurs 5 m above collection site. Conodont sample from fine-grained bioclastic, peloidal grainstone containing minor detrital quartz and glauconite. Abundant, very well preserved conodonts of the pseudopolygnathid-polygnathid- gnathodid biofacies; some postmortem transport within or from this biofacies. Open-marine deep ramp or middle to deep slope depositional environment. Carbonate bed is probably a gravity-flow deposit from slightly shallower water with some cannibalization of older Kinderhookian deposits.
Page 1 and 2: Geologic Studies in Alaska by the U
Page 3 and 4: CONTENTS Introduction Cynthia Dusel
Page 5 and 6: CONTENTS CONTRIBUTORS TO THIS BULLE
Page 7 and 8: GEOLOGIC STUDIES IN ALASKA BY THE U
Page 9 and 10: LATE HOLOCENE LONGITUDINAL AND PARA
Page 19 and 20: DEEP-WATER LITHOFACIES AND CONODONT
Page 25: Table 1. Locality register for key
Page 37 and 38: LITHOFACIES AND CONODONTS OF CARBON
Page 49 and 50: LITHOFACES AND CONODONTS OF CARBONI
Page 51 and 52: Table 1. Conodont faunules and lith
Page 55 and 56: DEPOSITIONAL SEQUENCES IN ATIGUN SY
Page 65 and 66: U-Pb AGES OF ZIRCON, MONAZITE, AND
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APPEAL FOR NONPROLIFERATION OF ESCA
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FAVORABLE AREAS FOR METALLIC MINERA
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GOLD AND CINNABAR IN HEAVY-MINERAL
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EARLY CENOZOIC DEPOSITIONAL SYSTEMS
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EARLY CENOZOIC DEPOSITIONAL S YSTEM
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RESERVOIR FRAMEWORK ARCHITECTURE, C
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GEOCHEMISTRY OF OPHIOLITIC ROCKS FR
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136 GEOLOGIC STUDIES IN ALASKA BY T
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GEOLOGIC STUDIES IN ALASKA BY THE U
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Table 1. Isotopic ages of intrusive
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Table 1. Isotopic ages of intrusive
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GEOCHEMICAL EVALUATION OF STREAM-SE
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20 GEOLOGIC STUDIES IN ALASKA BY TH
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Table 3. Summary of geochemical sig
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GEOCHEMICAL CHARACTER OF UPPER PALE
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RECONNAISSANCE GEOCHEMISTRY OF BASA
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OSTRACODE ASSEMBLAGES FROM MODERN B
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RUBIDIUM-STRONTIUM ISOTOPIC SYSTEMA
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RUBIDIUM-STRONTIUM ISOTOPIC SYSTEMA
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US. GEOLOGICAL SURVEY REPORTS ON AL
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U.S. GEOLOGICAL SURVEY REPORTS ON A
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U.S. GEOLOGICAL SURVEY REPOR TS ON
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REPORTS ABOUT ALASKA IN NON-USGS PU
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REPORTS ABOUT ALASKA IN NON-USGS PU
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Geologic Studies in Alaska by the U.S. Geological Survey, 1992

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