8/11/2019 Organism-sediment Relationship in Bisericani Formation

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Oral

Organism-sediment relationship in Bisericani Formation

(Bistri a Half-window)

Anistoroae, A.1& Miclu , C. 1

1Al. I. Cuza University of Iai, Department of Geology, 2A Carol I !lv, "## Iai, $omania% emails&an'a(anistoroae)ya*oo.'om%mi'laus)uai'.ro

Keywords: Outer Carpathians, rancea !appe, Bisericani Fm", sedimentology and ichnology, Cru#iana

$chnofacies

A sedimentological and ichnological study has been performed on Middle Member of Bisericani

Formation (that used to be considered riabonian in age! "rasu et al, 1#$$% from Falcu Anticline

(Bistri a alf'indo) of *rancea +appe, uter Carpathians%.

-een sedimentary facies )ere identified (conglomerates )ith green schist clasts ' " 1, ripple cross

laminated micro'conglomerates / "0, parallel laminated sandstones / -, ripple cross laminated

sandstones / -2, structureless sandy mudstones )ith ery rare green schist clasts / -i1, ripple cross

laminated siltstone / -i3, greenish'gray shale / M4% representing the results of different sedimentaryprocesses (debris flo), tractie currents and possible hemipelagic sedimentation%.

e hae determined seeral ichnogenera5 +*allasinoies, -seuoiloites, /o0eia, Imri'*nitus,

C*onritesand others. 6hey are mainly hypichnial forms according to Martinsson7s terminology (in

89dale et al., 1#$4% )ith cone: hyporelief, hori;ontal and sub'hori;ontal, some ornamented, feeding,

resting and d)elling traces of high abundance and diersity. e also hae analy;ed )ell presered

endichnialC? and are associated )ith abundant large

hypichnial forms, )hile the greenish'gray shale is characteri;ed by e:ichinial