Diversity of abyssal agglutinated foraminifera from Cenomanian to Santonian sediments of the North Atlantic ...

• Main Author: Kuhnt, Wolfgang
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1992
• Subjects: Drilling/drill rig; Leg43; Leg47; Leg93; Leg103; Glomar Challenger; Joides Resolution; Deep Sea Drilling Project DSDP; Ocean Drilling Program ODP; North Atlantic
• Online Access: https://dx.doi.org/10.1594/pangaea.690409; https://doi.pangaea.de/10.1594/PANGAEA.690409

Benthic foraminiferal assemblages of distinctive taxonomic composition occur at the top of benthic fossil-free black shales which correspond to the anoxic event at the Cenomanian/Turonian boundary in the North Atlantic abyssal DSDP/ODP sites 386, 398, 603 and 641. These assemblages consist of minute, thin-walled agglutinated foraminifera with low specific diversity of 2 to 4 species, variable abundance and dominance of few taxa (Haplophragmoides, Rhizammina and Glomospira). The species are inferred to be opportunistic, able to survive in low-oxygen environments and to be pioneers recolonizing the seafloor after cessation of bottom-water anoxia. Most species are characterized by test morphologies with high surface/volume ratios and single-layered wall structures, with loosely agglutinated grains, and small amounts of organic cement for agglutination. These features are best observed in material from ODP Hole 641A which has exceptional foraminiferai preservation because of its shallow burial depth. The ... : Supplement to: Kuhnt, Wolfgang (1992): Abyssal recolonization by benthic foraminifera after the Cenomanian/Turonian boundary anoxic event in the North Atlantic. Marine Micropaleontology, 19(3), 257-274 ...