Gupta, Anil K. and Satapathy, S. K. (2000): Latest Miocene-Pleistocene abyssal benthic Foraminifera from west-central Indian Ocean DSDP Site 236; paleoceanographic and paleoclimatic inferences

Leg/Site/Hole:
DSDP 24
DSDP 24 236
Identifier:
2003-063555
georefid

Creator:
Gupta, Anil K.
Indian Institute of Technology, Department of Geology and Geophysics, Kharagpur, India
author

Satapathy, S. K.
author

Identification:
Latest Miocene-Pleistocene abyssal benthic Foraminifera from west-central Indian Ocean DSDP Site 236; paleoceanographic and paleoclimatic inferences
2000
Journal of the Palaeontological Society of India
The Palaeontological Society of India, Lucknow, India
45
33-48
Multivariate (Factor and Cluster) analyses of abyssal benthic foraminifera from 31 latest Miocene-Pleistocene samples from Deep Sea Drilling Project (DSDP) Site 236, west-central Indian Ocean (eastern Somali Basin) revealed significant changes. R-mode factor and Q-mode cluster analysis of 29 highest ranked species identify 5 environmentally significant assemblages and 5 clusters reflecting distinct environments of deposition. Cibicides refulgens, Ehrenbergina carinata, Cymbaloporetta squammosa, Bolivina pusilla, Astrononion umbilicatulum and Quinqueloculina weaveri mark assemblage 1. This assemblage, characterizing Cluster II, is inferred to reflect high flux of organic matter. Assemblage 2 of Bolivinita quadrilatera, Uvigerina proboscidea, Nonionella japonicum, Bolivina spathulata and Uvigerina porrecta, characterizes Cluster IV, suggesting low oxygen content and sustained flux of organic matter from high surface productivity. Cibicides bradyi, C. wuellerstorfi, Oridorsalis umbonatus and Melonis barleeanum typify Assemblage 3, which is indicative of intermediate flux of degraded organic matter characterizing Cluster I. Assemblage 4, marked by Reussella spinulosa, Astrononion umbilicatulum, Bolivina spathulata, Nonionella japonicum and Bolivina pusilla, corresponds to Cluster III and suggests low-oxygen and organic carbon rich environment. Nuttallides umbonifera, Pyrgo murrhina and Cibicides wuellerstorfi typify assemblage 5. This assemblage corresponds to Cluster V and indicates well-oxygenated, corrosive bottom water.
English
Serial
Coverage:Geographic coordinates:
North:-1.4037
West:57.3851East: 57.3851
South:-1.4038

Stratigraphy; assemblages; benthic taxa; Cenozoic; Deep Sea Drilling Project; DSDP Site 236; faunal list; Foraminifera; Indian Ocean; Invertebrata; Leg 24; marine sediments; microfossils; Miocene; Neogene; paleo-oceanography; paleoclimatology; Pleistocene; Protista; Quaternary; sediments; Somali Basin; statistical analysis; Tertiary; upper Miocene;

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