Maastrichtian-Early Danian radiolarians and ostracodes from ODP Site 1001B, Caribbean Sea

Abstract

-The ODP, Site 1001B (Leg 165), located in the Caribbean Sea, presents a well preserved sedimentary succession ranging from the Cretaceous to the Neogene that consists predominantly of pelagic limestone. The main objective of this article is to study taxonomically the Maastrichtian radiolarian and the Maastrichtian-early Danian ostracode faunas recovered in the studied site and to compare them to faunas previously described elsewhere. Despite the discontinuity of the occurrences and the scarcity of specimens, 45 radiolarian species and seven ostracode species assigned to six genera, were identified. The radiolarians were recovered only in the cores 21R and 20R and correspond to a typical Upper Cretaceous fauna, containing even species considered as index fossils such as Orbiculiforma renillaeformis (Campbell & Clark) Pessagno. The seven ostracode taxa occur in the Maastrichtian-early Danian interval. The single specimen of Paleoabyssocythere sp. here recorded could not be ascribed to none of the described species and possibly constitutes a new taxon. The presence of the ostracode association Paleoabyssocythere-Krithe-Bairdoppilata-Cytherella suggests deposition in a bathyal or outer shelf environment.

Late Cretaceous radiolarian biochronology of the Pedro Brand section, Tireo Group, eastern Central Cordillera, Dominican Republic: A contribution to the stratigraphy of the Caribbean Large Igneous Province

“…The 40 Ar-39 Ar ages for the intrusion of the basaltic dyke in the Pedro Brand section studied here is 75.1 ± 1.1 Ma, which consistently indicates that the sequence is older than late Campanian. In addidion, our radiolarian assemblages differ from those dated as late Maastrichtian in the Caribbean Colombia Basin (Aumond et al, 2009;Kochhann et al, 2013).…”

Expedition 396 methods

“…Dry samples prepared for foraminifer examination also were examined for the presence of ostracods at selected sites. Ostracod assignments follow Ducasse and Peypouquet (1979), Coles and Whatley (1989), Malz (1989), Coles et al (1994), Guernet and Bellier (2000), Aumond et al (2009), Alvarez Zarikian (2009, 2015, Yamaguchi (2018), Yamaguchi and Norris (2012), and Yamaguchi et al (2017aYamaguchi et al ( , 2017b. Species identification was made routinely on core catcher samples and occasionally on samples taken from selected working-half sections.…”

Cretaceous–Lower Paleogene ostracods from the Pelotas Basin, Brazil

“…Worldwide, there are many other places that show sections with the K-Pg boundary; however, few of these are well preserved and contain ostracods. Some of these studies were carried out in Argentina (Bertels 1969b), Tunisia (Said-Benzarti 1998), Texas (Maddocks 1985), Algeria (Damotte and Fleury 1987), the north of Alaska (Browers and De Deckker 1993), Mali (Colin et al 1998), Brazil (Fauth et al 2005), Suriname (Leg 207) (Guernet and Danelian 2006) and the Caribbean Sea, ODP Site 1001B (Leg 165) (Aumond et al 2009). Therefore, the purpose of this paper is to document the ostracod species present in Cretaceous and Lower Paleogene strata of the Pelotas Basin and trace previous palaeoecological and palaeo-environmental considerations.…”