(Table 1) Distribution and numerical abundance of foraminifera of sediment core CRP-3

Strong, C Percy;Webb, Peter-Noel

Description

A foraminiferal fauna comprising c. 33 genera and c. 53 species was recovered from a suite of 156 Lower Oligocene sediment samples, mostly muddy sandstone and siltstone, selected over the 2.80 - 823.11 mbsf depth range in the CRP-3 drillhole. All foraminifers, except for 2 isolated specimens, occurred above 340 mbsf, with 54 of 103 samples from above this depth being fossiliferous. At a generic and even a specific level, the fauna contains many components for the present-day Antarctic foraminiferal biota, indicating that its origin is at least as old as early Oligocene.Foraminiferal assemblages represent a single biofacies which is characterised by low diversity, and by dominant and persistent occurrences of Cassidulinoides chapmani, other Cassidulinoides and Globocassidulina species, and Stainforthia sp. These taxa and commonly accompanied by Cibicides lobatulus, Epistominella exigna, Fissurina spp. Nonionella spp., and Oolina spp. Large miliolids occur as isolated specimens at various levels. Planktic species are absent, and agglutinated taxa occur only rarely and sporadically. Preservation generally is fair good, while absolute abundance is very low, with a maximum of c. 6 specimens/gram, and most samples containing <1 specimen/gram. These assemblages probably represent mid to outer shelf depth (50-200 m) in glacially influenced environments with a high sedimentation rate and poor oceanic connections.Although the CRP-3 fauna closely resembles the one from Foraminiferal Unit III as defined in CRP-2/2A (CRP-2/2A Science Team, 1999; Strong & Webb, 2000, hdl:10013/epic.28260.d001), absence of some species, and the first records of others in the uppermost CRP-3 section, is consistent with an interpretation of minimal overlap between the CRP-2/2A and CRP-3 sediments. The fauna also appears correlative with the Globocassidulina-Cassidulinoides-Trochoeiphidiella Assemblage Zone from lower DSDP-270, and with faunas from the lower but not lowermost, section at CIROS-1.

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Metrics

Dataset Index

132.4

FAIR Score

92%

Citations

199

Mentions

0

Metrics Over Time

Publication Details

DOI

Publisher

PANGAEA

License

Creative Commons Attribution 3.0 Unported

Assigned Domain

Subfield

Atmospheric Science

Field

Earth and Planetary Sciences

Domain

Physical Sciences

Confidence Score

95%

Source

Open Alex

Keywords

DEPTH, sediment/rockDepth, top/minDepth, bottom/maxLithologic unit/sequenceNumber of speciesSpecimen countForaminifera, benthic preservationAnomalina spp.Anomalinoides cf. eoglabraAnomalinoides fasciatusAnomalinoides globulosusAnomalinoides miosuturalisAnomalinoides spp.Astacolus spp.Baggina cf. breviorBulimina sp.Cassidulinoides bradyiCassidulinoides braziliensisCassidulinoides chapmaniCribroelphidium sp.Cibicides lobatulusCibicides cf. temporatusCibicides spp.Cyclammina incisaDentalina sp.Discorbis sp.Epistominella exiguaEponides bradyiFissurina fimbriataFissurina marginataFissurina spp.Gavelinella spp.Globigerina sp.Globocassidulina crassaGlobocassidulina subglobosaGyroidina orbicularisHaplophragmoides spp.Hanzawaia sp.Karrerculina sp.Lenticulina spp.Melonis barleeanusMelonis graniferumMelonis spp.MiliolidaeNodosaria spp.Nonionella bradiiNonionella irideaNonionella magnalinguaNonionella spp.Oolina apiculataOolina apiopleuraOolina globosaParafissurina lateralisPlanularia sp.Pullenia subcarinataQuinqueloculina spp.Reophax sp.Stainforthia sp.Textularia sp.Echinodermata fragmentsFecal pelletsForaminiferaMolluscaOstracodaSiliceous spiculesForaminifera, benthicDiatom abundanceCore wireline systemCounting, foraminifera, benthicCounting &gt;125 µm fractionCRP-3Sampling/drilling from iceCape Roberts Project (CRP)

Normalization Factors

FT

94.23

CTw

1.00

MTw

1.00