Abstract
Three major geological events: The cretaceous-Paleogene (K/Pg)
transition, Dan-C2, and the Latest Danian Event (LDE) during the Early
Paleocene geologic period caused potential impacts over mass extinctions
of several marine life and also rapid change in climate from icehouse to
warmhouse condition. The effects of these events on the marine community
in the Indian Ocean are not well understood in comparison to other
oceans. Here we investigate benthic foraminiferal diversity patterns,
morphotypes, and oxygen conditions along with the carbonates and
magnetic susceptibility records in the Indian Ocean sediments to
understand the Danian Warm World (DWW). Deep-sea sediments from the
International Ocean Discovery Program (IODP) Site U1457 (Laxmi basin,
Northern Indian Ocean) at ~1100 meters below the
seafloor (mbsf) of the Danian period (c. 66 – 61.6 Ma) are examined,
which suggest that the foraminifera subsisted across major events.
Species belonging to Bolivina, Glandulina, Hoeglundina, Parrelloides and
Quadrimorphina genus were dominant above the K/Pg boundary whereas
Bolivina, Bulimina, Cassidulina, Cornuspira, Gyroidinoides, Melonis,
Oolina, Pullenia, Reussoolina and Rutherfordoides were dominated across
the hyperthermal events. We also calculated the average oxygen content
at 0.16 ml/L in accordance with oxyphilic species abundance, which
serves as supportive evidence, in defining Laxmi basin favours a suboxic
to dysoxic environment. The benthic foraminiferal diversity pattern,
primary anomalies of calcium carbonates, magnetic susceptibility, and
previous global datasets of carbon and oxygen isotopes attempted to mark
the period of geologic events at the study site.