10.6084/m9.figshare.3454058.v1
Sonal Khanolkar
Sonal
Khanolkar
Pratul Kumar Saraswati
Pratul Kumar
Saraswati
Some observations on an atypical planktic foraminifer from the Middle Eocene of Kutch, India
Geological Society of London
2016
Kutch
section
Orbulinoide
SEM
Middle Eocene
benthic foraminifera
planktic foraminifer
scanning electron microscope
wall texture
Geology
2016-06-21 11:52:12
Dataset
https://geolsoc.figshare.com/articles/dataset/Some_observations_on_an_atypical_planktic_foraminifer_from_the_Middle_Eocene_of_Kutch_India/3454058
<p>An atypical planktic foraminifer having close resemblance with <em>Orbulinoides</em> Blow & Saito, 1968 is recorded from a lignite mine section in Kutch, western India. It is practically indistinguishable from
<em>Orbulinoides</em> under optical microscope due to general similarities in chamber morphology, coiling mode, aperture number and character,
but differs in wall texture when observed under scanning electron microscope (SEM). The wall is characterized by pores of
variable size and irregularly distributed pustules unlike the spinose wall of normal <em>Orbulinoides</em>. Based on the SEM micrographs some specialist opinion suggested that the taxon might be a benthic foraminifer. The morphological
features of the studied foraminifera are, however, distinctly different from benthic foraminifera with a planktic stage. The
associated larger benthic foraminifera correlate the section with the carbonates of Middle Eocene (Bartonian) age in the adjoining
areas of Kutch. The accompanying foraminiferal assemblage suggests a near-shore, brackish-water, semi-enclosed depositional
environment. It is suggested that the aberrant wall texture was possibly due to environmental stress developed in the restricted
basin. Due to incongruous wall texture and to its occurrence as the only planktic foraminifera in the section, the nomenclature
of the reported foraminifera is kept open.
</p>