The Late Cretaceous–Early Paleocene palaeobathymetric trends in the southwestern Barents Sea — Palaeoenvironmental implications of benthic foraminiferal assemblage analysis

The mid/late Eocene transition in the Eastern Carpathians (Romania) based on foraminifera and calcareous nannofossil assemblages

“…Spec i mens of tu bu lar taxa (Rhizammina, Bathysiphon, Rhabdammina, Nothia), usu ally re cov ered only as frag ments, were counted just for con sis tency. Palaeo ecologi cal meth ods in clude the ag glu ti nated foraminifera morphogroups (Nagy et al, 1995;Van der Akker et al, 2000;Kaminski and Gradstein, 2005;Cetean et al, 2011;Murray et al, 2011;Setoyama et al, 2011Setoyama et al, , 2013 and the di ver sity of foraminiferal as sem blages (Hulbert, 1971). The morphogroup anal y sis is based on the con cept of foraminifera mor phol ogy and the idea that in di vid u als with dif fer ent test shapes have differ ent hab i tats and dif fer ent feed ing strat e gies, there fore the changes in the rel a tive abun dance of morphogroups in the assem blages can re flect en vi ron men tal changes (Corliss, 1985;Jones and Charnock, 1985;Murray et al, 2011).…”

“…Ex cept for the flat tened ir reg u lar Ammolagena spec i mens (M3b), all the morphogroups of ag glu ti nated foraminifera described by Nagy et al (1995), Van der Akker et al (2000), Kaminski and Gradstein (2005), Cetean et al (2011), Murray et al (2011), and Setoyama et al (2011, 2013 are pres ent in the sec tion in ves ti gated. The graphic dis tri bu tion of the morphogroups (Fig.…”

Assessing the composition of fragmented agglutinated foraminiferal assemblages in ancient sediments: comparison of counting and area-based methods in Famennian samples (Late Devonian)

“…Tubular forms appear to be one of the key components of some agglutinated foraminiferal assemblages corresponding to deepwater, low-energy habitats (Murray et al, 2011;Setoyama et al, 2011). However, their elongated shape makes them fragile and prone to fragmentation; counting each fragment as a unit may overestimate the contribution of this morphotype to the assemblages (Setoyama et al, 2013).…”

“…However, their elongated shape makes them fragile and prone to fragmentation; counting each fragment as a unit may overestimate the contribution of this morphotype to the assemblages (Setoyama et al, 2013). It has thus been proposed to take into account the cumulated length of the tubular fragments to get a better estimate of their abundance (Setoyama et al, 2011). The drawback of this approach is to deliver an estimate for the tubular (ED1) morphogroup only, which is not comparable with other morphotypes estimated by counting, preventing the estimation of the relative proportion of each morphotype.…”

“…1a, b). This morphotype is thought to trace deep environments (Nagy et al, 1995;Setoyama et al, 2011). However, because of the fragility of these tubular forms, their estimate in the assemblages may be biased due to fragmentation, therefore artificially biasing their representation in the assemblages (Murray et al, 2011).…”