Pliocene benthic foraminiferal abundances of ODP Hole 105-646B from north Atlantic

• Main Authors: Zhang, Jijun, Scott, David B
• Format: Dataset
• Language: English
• Published: PANGAEA 1996
• Subjects: 105-646B; Ammobaculites sp.; Ammodiscus sp.; Ammotium sp.; Astrononion echolsi; Astrononion umbilicatulum; Bigenerina sp.; Bolivina cf. alata; Bolivina inflata; Bolivina lowmani; Bolivina pseudoplicata; Bolivina pseudopunctata; Bolivina pseudothalmanni; Bolivina pygmaea; Bolivina simplex; Bolivina spp.; Bulimina alazanensis; Bulimina sp.; Bulimina tessellata; Cassidulina laevigata; Cassidulina reniforme; Cassidulina sp.; Cassidulinoides tenuis; Cibicides lobatulus; Cibicidoides bradyi; Cibicidoides spp.; Cornuspirella diffusa; Counting; Cyclammina cancellata; Dendrophrya sp.; Dentalina communis; DEPTH; sediment/rock; Discorbinella bertheloti; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Ehrenbergina trigona; Elphidium sp.; Epistominella exigua; Eponides polius; Eponides sp.; Eponides tumidulus; Eponides weddellensis; Fissurina spp.; Florilus sp.; Foraminifera; benthic; benthic agglutinated indeterminata; North Atlantic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.758101; https://doi.org/10.1594/PANGAEA.758101

Our benthic foraminiferal data clearly indicate eight layers of deep-water turbidites during the Messinian (MTL 1-8) and one in the early Pliocene (PTL 1) in Ocean Drilling Program Leg 105, Site 646B. These deep-water tuibidite deposits are characterized by highly concentrated agglutinated marsh benthic foraminifera (e.g., Trochammina cf. squamata, Ammotium sp. A, Miliammina fusca), rounded quartz, polished thick-walled benthic foraminifera, wood fragments, plant seeds, plant fruit, and highly concentrated mica and are interbedded with sediments containing deep-water benthic faunas. We suggest these turbidites deposited during sea-level low stands (approx. 80-100 m below sea level), and their ages are tentatively correlated to 6.59, 6.22, 6.01, 5.89, 5.75, 5.7, 5.65, 5.60, and 5.55 Ma, respectively, based on the Messinian oxygen isotope enrichments at Site 552A of Deep Sea Drilling Project Leg 81. The turbidites layers during the late Messinian, coeval with frequent climate changes suggested by six oxygen enrichment excursions of Site 552A, may have been in part linked to the late Messinian evaporite deposits in the Mediterranean Basin. The most profound climate changes at 5.75 and 5.55 Ma may have been related to the Lower and Upper Evaporites in the Mediterranean Basin.