Upper Cretaceous, K/T boundary, and Paleocene agglutinated foraminifers from Hole 959D (Côte d'Ivoire-Ghana Transform Margin)

Abstract

Upper Cretaceous agglutinated foraminifer assemblages from Hole 959D of Ocean Drilling Program (ODP) Leg 159, Côte d'Ivoire-Ghana Transform Margin, reflect the subsidence history and paleoceanography of the widening equatorial Atlantic gateway. Five benthic foraminifer assemblage types are recognized: (1) Santonian and the lowermost Campanian assemblages (Cores 159-959D-65R and 64R) are characterized by the occurrence of bathyal calcareous benthic foraminifers with an increasing proportion of agglutinated foraminifers. The disappearance of calcareous foraminifers and assemblages exclusively composed of organically cemented agglutinated forms in Section 159-959D-65R-3 reflects the subsidence of the seafloor below the calcite compensation depth (CCD); (2) lower Campanian "biofacies B" assemblages (Cores 159-959D-63R through 61R) are exclusively composed of low-diversity agglutinated foraminifers, accompanied by abundant and occasionally well-preserved radiolarian assemblages; (3) middle Campanian to upper Maastrichtian deposits (Cores 159-959D-59R through 49R) contain an exclusively agglutinated Rzehakina epigona biofacies, which is well-known from middle to deep bathyal sites along the North Atlantic margins; (4) a change in agglutinated foraminifer assemblage composition toward morphologies commonly observed in present infaunal habitats and the common occurrence of the presumably infaunal genus Spiroplectammina are observed in Core 159-959D-48R. This change in agglutinated foraminifer assemblages corresponds to the Tethyan early Paleocene "Spiroplectammina event;" (5) a diversified Paleocene "Lizard Springs type" assemblage is characterized by several diverse Rzehakina, Saccamina, and Haplophragmoides species. Assemblages from Cores 159-959D-48R through 44R display high species diversity and reflect the deepest (lower bathyal to upper abyssal) paleobathymetry.Ranges of agglutinated foraminifer marker species and occurrences of paleoceanographic events within this biostratigraphic framework are almost identical to those observed in the North Atlantic, in the Western Tethys, and along the conjugate Brazilian margin. These observations lead us to confirm that a deep-water circulation system common to the North and South Atlantic has been active at least since the Santonian.

Euxinia and primary production in Late Cretaceous eastern equatorial Atlantic surface waters fostered orbitally driven formation of marine black shales

“…Reports on Coniacian to Lower Campanian Organic Carbon -Rich Marine Sediments Representing the OAE-3 (Coniacian-Santonian) and the Succeeding ''Biosiliceous Event'' (Lower Campanian) as Proposed byKuhnt et al [1998] in the Atlantic and Tethyan Ocean a…”

Agglutinated Foraminiferal Acmes and Their Role in the Biostratigraphy of the Campanian–Eocene Outer Carpathians

“…The authors of [34] indicated the universal biostratigraphical use of C. gigantea abundant assemblages in the Outer Carpathians, which was the basis for establishing the Caudammina gigantea acme zone of late Santonian-early Maastrichtian age. The Caudammina gigantea zone is used commonly for North Atlantic stratigraphy; it ranges from middle-upper Campanian to Maastrichtian ( [35][36][37][38] and references therein). Similar use was introduced in the Contessa Highway section near Gubbio Italy [39].…”

“…It is not so common as the Eocene acme. In different intervals of the Paleocene, an increase in S. spectabilis is commonly noted from the Atlantic-Tethyan and Boreal realms ( [1,35,89,[104][105][106] and references therein). It is one of the most common species in the Paleocene at Site 1511 in the Tasman Sea [69].…”

“…The S. spectabilis assemblages occur more often in green or grey shales rather than in red or variegated shales. The species preferred environments with higher sea-floor carbon flux and siliciclastic flux [1,89], and it is one of the opportunistic species that formed a post-crisis acme after the Cretaceous/Paleogene boundary event [35].…”

Biostratigraphy and paleoenvironment of the Upper Cretaceous deposits in the northern Tarcău Nappe (Eastern Carpathians) based on foraminifera and calcareous nannoplankton

“…The first occurrence (FO) of Caudammina gigantea was observed in sample 15 (lower part of the CC22 Zone of calcareous nannoplankton). Caudammina gigantea was considered by Kuhnt et al (1998), Bąk (2000), and Cetean et al (2011), as not living above the middle bathyal zone and it seems that its first occurrence is diachronous along the Carpathians. In the Polish Outer Carpathians, Olszewska (1997) Planktonic foraminifera occur only in the basal part of the section (grey marlstones) with high proportions in samples 4 and 11 (Fig.…”