Article
Early Cretaceous duvaliids (Belemnitida: Mollusca) of the Rarău Syncline (Eastern Carpathians, Romania)
Paul Țibuleac - “Alexandru Ioan Cuza” University of Iaşi, Department of Geology, 20A Carol I Blv, 700505 Iaşi, Romania, Department of Geology
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Abstract:
The present paper focuses on the Early Cretaceous duvaliids of the Rarău Syncline, including
the recently-sampled specimens from the grey marly matrix of the so-called “Gura Sadovei
Breccia” and the previously-described ones from the “I. Turculeț” Collection (Museum of
Paleontology, “Alexandru Ioan Cuza” University of Iaşi).
So far, the duvaliids of the Rarău Syncline indicate two main time span groups, namely latest
Berriasian – earliest Valanginian (from the “Gura Sadovei Breccia”), and Hauterivian –
Barremian (from the wildflysch deposits). The oldest include the following taxa: Duvalia lata
morph div., D. aff. haugi, D. ex. gr. miravetesensis, Duvalia sp.1., and the younger D. dilatata,
D. ex. gr. dilatata, D. binervioides, Duvalia sp. 2, and ?Curtohibolites sp. Several previous
determinations have been updated.
The duvaliids include mainly mature specimens, with few juvenile ones occurring. There are
both well-preserved and fragmented rostra, but few internal moulds were observed. The
reworking of records in the “Gura Sadovei Breccia” can be advocated given the frequent
fragmentation and small clasts intruded in the rostrum, or in the phragmocone/phragmocone
filling. Sometimes, fine diaclases filled with calcite cross the specimens.
The various rocks of different ages and sizes, all randomly oriented, suggest a fissure-fill breccia
along the fault which crosses the “Aptychus Beds” anticline in the outcrop.
Keywords:
“Aptychus Beds,” Duvalia, “Gura Sadovei Breccia,” Berriasian-Valanginian, wildflysch,
Hauterivian-Barremian
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