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Home My WebLink AboutGMC Data Report No. 337Palynology and micropaleontological evaluation of core samples (102.6'-1,142.5') from the U. S. Navy Sentinel Hill Core Test No. 1. .-. •r Created December 2006 Total of 5 pages in report plus original data CD Alaska Geologic Materials Center Data Report No. 337 Palynological and Micropaleontological Evaluation of Core Samples from the Sentinel Hill Core Test #1, Central North Slope, Alaska June 2tN16 Summary Ten conventional core samples {102.601142.5 ft) from the Sentinel Hill Core Test No. 1, Central North Slope, Alaska, were examined for organic-walled palynomorphs, and two samples {699.6 ft, 11455 ft} were examined for foraminifers. The sample at 102.6 ft is early Maastrichtian in age. The interval between 364.3 ft and 941.3 ft is late Campanian, and the lowermost sample at 1142.5 ft is early Campanian. Palynology Ten conventional core samples occupy an interval ranging in age from early Campanian to early Maastrichttan (see Figure 1 for sample information and observed distribution of taxa). The uppermost sample (102.6 ft) contains a relatively Iow-diversity terrestrial assemblage with few age-diagnostic taxa. The next sample down (364.3 ft), however, contains a rich and characteristically late Campanian assemblage including in particular numerous specimens of the important late Campanian indicator pollen species Aquilapollenites trialatus. Given the absence of typical late Maastrichtian taxa from the uppermost sample, we regard it as being early Maastrichtian in age. The late Campanian assemblage persists throughout most of the rest of the core, down to 941.3 ft, and is characteristically non-marine in nature. The Lowermost sample (1142.5 ft}, however, contains a population of marine dinoflagellate cysts typical of early Campanian strata, including the major marker species Spongodinium delitiense and Chatangiella ditissitna. Overall, recovery and preservation of palynomorphs was excellent throughout, and more detailed sampling, if desired, would permit clearer resolution of the chronostratigraphy in this core. Alaska GMC Data Report 337 Page No. 1/5 F©raminifera ~'~ fie. Indeterminate Environment. Indeterminate ~ a. Barren of Foraminifera Washed Lithoio~v. Dark gray silty micaceous mudstone or shale. 1142.5'C A~e• Late Cretaceous Probable Campanian Zone. Probable F-5 Environment. Inner to Middle {Inner to Middle) Fauna. Ammobaculites wenonahae (X} Bathysiphon sp. (R} Eoeponidella strombodes (X} Haplophragmoides 8onanzaensis (R} Haplophragmoides rota (R) Quinqueloculina sp. (X} Trochammina ribstonensis (F} Trochammina whittingtoni (F} Verneuilinoides fischeri {F} Cenosphaera spp. (pyritized} (F) Spongodiscus sp. (R} Diatoms (pyritized) (F} Pyrite (C} Tar (F} LCM (F) t~Vashed Lithology_ Dark gray to black slightly silty pyritic shale. Alaska GMC Data Report 337 Page No. 2/5 Alaska GMC Data Report 337 Page No. 3/5 no. of taxa per sample 40 20 0 ._..._ o early MAASTRICHTIAN c°y ~I 0 0 U O S ~ N ~ w .` ~~ Q Z 4 a Q V a~.r early CAMPANIAN cow ~ {feet) 102.6 364.3 608.3 615.5 699.8 781.2 832.6 900.9 941.3 =~~.~ r ~~ ~~ ^ L O i ~ - ~_ o ~- ~, _ _ _ ~ ~ ~_ N ~ ~ N ~~ ~ ~ - a ~ a- s ~ ~_ ~ a ~ a ~ x Q ctS v N m m to _ r = c '~ y ~ '~ ~ ~ a > - O o O ~ U O _ n is ~ co .~ ti _ __ _ ~ '~ '9 0 0 = < G G Q Q Q Q ^ '^ N M 00 r (p 00 N ^ C CO 'tt r N r L!') ~- • • _ _ _ • • • • ~'~ . ~ • • _ _ • _ _ • _ o _ • - • i v _ • • • _ _ _ N 3 ai a i_ ,F; (~ N y N C _ C N Q. ~ +"j II ~C ~ C N N ~ ~ = u°i c a ~ 3 a~ ~ ~ U (p N '~ a~ O Vi cSf O Y Q .~ N ~ a o 'o ~ ~, m a~ 'c N :o ~ a f4 ,~., N N ~ ~N ~ N 'n fn ~ O ~ 2 Fes- C7 ~ ., . ~-- N M d' to l0 f~ 00 C C Figure 1. Stratigraphic sistribution of organic-walled microfossils, Serrtinal Hill Core Test No. 1. D a N sL 3 0 :1 a+ z m 0 ~+ w w v -v :v ro a 0 .p c,rt 8 9 10 11 12 13 14 15~ 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 TsugaepollenRes sp. - inlet, small Gleichetuidftes senorticus d. Convetnacosispotibes sp. -small, pale, vague SterelQranlSporiS reQlUs cf. Anacolosidites sp. -indef. Betulaceoipoilenites/Carpinuspollenites group CarnarozonosporRes sp. - inlet., small Selagosporis sp. 1 Taxodiaceaepollenites hiaws 1 I • i ~: I Aquilapollenites cf. fusiformis Erdmannipollis procumbentiformis Tricolporopollenites sp. -indef., small, prolate Aquilapollenites spp. -inlet. I Polycingulatisporites cf. reduncus -vague ornament Echinatisporis spp. -inlet. Sigmopollis carbonis linear septate fungal hypha Fibulapollis scabratus Hannisporis scollardensis Expressipollis cf. accuratus I Ven'ucosisporites sp. -inlet., small I Cibotiumspora juncta Lobatia involucrata cf. Divisisporites sp. -inlet Undulatisporites sp. -indef. Ovoidites arcticus Trilites sp. -indef. 1 Podocarpidites sp. -indef. cf. Perinopollenites sp. -indef. Cicatricosisporites sp. 2 I I cf. Loranthacites sp. -inlet. ( Anar:olusidiles/1 xln~•~:~alxillr: •atritm: Cranwellia subtills Aquilapollenites amygdaloides Sequoiapollenites polyformosus nv~idite~ p~rvus ,. i 1~ I~ I ~. I I 1 ~1 I • • • ,I I • • I I i I I I I ..~ 1 1 I 1 ~ ~~~~ ~~~, 'I i I I I I Y.~ 16 ~ , 58 Azonia cribrata 12 Bewlaceoipollenites/Carpinuspollenites group 1 bisaccate gymnosperm pollen - inlet. 51 Camarozonosporites ambigens 13 Camarozorlosporites sp. - inlet, small 11 cf. Anacolosidites sp. -inlet. 9 cf. Converrucosisporites sp. -small, pale, vague 32 cf. Divisisporites sp. -indef. 69 cf. Exochosphaeridium sp. -indef. 40 cf. Loranthacites sp. -indef. 38 cf. Perinopollenites sp. -indef. 68 30 Cibotiumspora juncta 35 39 Cicatricosisporites sp. 2 60 Cicatricosisporites spp, -inlet. 59 Cicatricosisporites venustus 65 Circulodinium distinctum group 47 Cranwellia rumseyensis (?) 42 Cranwellia subtilis 3 Deltoidospora spp. -inlet. 73 Densosporites sp. -inlet. 63 Dictyophyllidites sp. -indef. 23 Echfnatisporis spp. -indef. 19 Erdmannipollis procumbentiformis 28 Expressipollis cf. accuratus 26 Fbulapollis scabratus 50 Foveosporites spp. -inlet. 52 Gleicheniidites "denticulatus" 8 Gleicheniidites senonicus 55 Hamulatisporis? sp. -inlet., large 27 Hannisporis scollardensis 49 Inundatisporis tappaniae . S I ~evigatosporites spp. -indef. 46 25 linear septate fungal hyplia 31 I ohatta Involucr<11.r ~).3 I yruluulbu9clilr•: •.I~ nt~1c•I , •.nutll, luu• w N 3 t'~ 0 w s1 c~ 0 w w V -~ ou ca m z 0 v, cn '~L 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 l;ranVYBllla SUDUII3 Aquilapollenftes amygdaloides Sequolapollenites polyformosus Ovoidites parvus Cranwellia rumseyensis (?) Reticuloidosporftes pseudomurli Inundatisporis tappaniae Foveosporites spp. -indef. Camarozonosporites ambigens Gleicheniidites "denticulatus" Lycopodiacidites sp. -indef., small, fine Ornamentifera sp. -indef. Hamulatisporis? sp. -indef., large Annulispora sp. -indef. Matonisporites sp. -indef. Azonia cribrata Cicatricosisporites venustus Cicatricosisporites spp. -indef. Antulsporites? sp. -indef., vague ornament Dictyophyllidites sp. -indef. Ovoldites spriggii Circulodinium distinctum group peridinioid indef., pale, thin cf. F~cochosphaeridium sp. -indef. Oligosphaeridium complex Tenua hystrix Trichodinium? sp. -indef. I I .. , ii ~Z yU ~ ~1 ~ ~ i 1 '!. 4 f ( ! ~' ?' a 1 1 I I ;; I i :1' S' .t .:.: su 7 m rn ~ o ~ ~ ~ o ~' ) • i nonmarine, pollen/spores I nonmarine algae fungal I marine dinoflagellates l reworked Mississippian spore TAXA DIVERSITY (see graph at left): Nonmarine Marine Reworked Mississippian Tote. N 1 1 i N 1 N ~ i ()1 V7 ~ aD V A O Ln 11 W au 0 0 0 0 0 0 0 0 0 j o 0 0 0 0 0 0 0 0 (~ 1 1 1 N 1 N i 1 1 W ~ •. 25 linear septets fungal hypha 31 Lobatia Involucrata 53 Lycopodiaddites sp. - indef., small, fine 17 - 57 Matonisporites sp. -indef. 70 Oligosphaeridium complex 54 Ornamentifera sp. -indef. 4 Osmundacidites wetlmanii 34 Ovoidftes arcticus 45 Ovoidites parvus 64 Ovoidites spriggii 66 peridinioid indef., pale, thin 37 Podocarpidites sp. -indef. 22 Polycingulatisporites cf. reduncus -vague ornament 48 Reticuloidosporites pseudomurii 6 Retitrilefes spp. -indef. 61 14 Selagosporis sp. 1 44 Sequoiapollenites polyformosus 24 Sigmopollis carbonis 67 10 Stereigranisporis regius 2 Stereisporites spp. -indef. 15 Taxodiaceaepollenites hiatus 71 Tenua hystrix 72 Trichodinium? sp. -indef. 20 Tricolporopollenites sp. -indef., small, prolate 36 Trilites sp. -indef. 7 Tsugaepollenites sp. -indef., small 33 Undulatisporites sp. -indef. 29 VerrucosisnnritPG sn - inrir t emnu