section (Durango State, northeast Mexico). Journal of South American Earth Sciences, 42,
150–158. http://dx.doi.org/10.1016/j.jsames.2012.10.009
igneous clasts in the outer nappes
of the eastern carpathians: indicators
of late cretaceous basin segmentation
Marian Munteanu1* | Mihaela Melinte-Dobrinescu2 | Sarolta
Lőrincz1 | Relu-Dumitru Roban3 | Mihai Ducea3,4
1| Geological Institute of Romania, 1 Caransebeş Street, Bucharest, Romania:
*marianmunteanu2000@gmail.com
2| National Institute of Marine Geology and Geo-ecology, 23-25 Dimitrie
Onciul Street, Bucharest, Romania
3| University of Bucharest, Faculty of Geology and Geophysics,
1 Nicolae Bălcescu Boulevard, Bucharest, Romania
4| Department of Geosciences, University of Arizona, Tucson, USA
Clasts of felsic igneous rocks occur within the Cretaceous of the Moldavide
nappes which constitute the outer structures of the Eastern Carpathians.
These clasts are common in the Lower Cretaceous of the Inner Moldavides, i.e., in the Teleajen, Audia and Macla nappes. U-Pb zircon ages determined on felsic clasts of the Aptian–Albian successions belonging to
the Audia Nappe yielded ages of c. 600 Ma (Roban et al. 2020). A particular
setting occurs in the southern part of the Eastern Carpathians Bend, where
the Macla Nappe is thrust over a tectonic unit described as the Variegated
Clay Nappe (Ştefănescu 1995). This unit is interposed between the northern
Macla Nappe and the southern Tarcău Nappe. The Variegated Clay Nappe
is composed mainly of grey, red and green clays, greenish marls and calcareous sandstones. Granite, granodiorite and felsic porphyry fragments
occur as arkose, lens-like feldspar sands and gravels with fragments of
felsic igneous rocks up to 10 cm in size. In the sediments of the Variegated
Clay Nappe, enclosing lense-shaped feldspar sand and arkose intercalations, the nannofossils indicate an Early Campanian age. Zircon dating of
the igneous clasts yielded ages close to 600 Ma, suggesting a source similar to the one of the clasts found in Lower Cretaceous successions of
the Inner Moldavides (Roban et al. 2020). Seeing that the Moesian Platform
was submerged from the Albian to the end of the Cretaceous, this cannot
have been the source of the igneous rock clasts in the Campanian.
The mineralogical and petrographic selectivity of the coarse material
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intercalated in the sediments of the Variegated Clay Nappe, i.e., 90% feldspar in the arenites, and similar proportions of granitoid and porphyry clasts
in rudites, suggest a proximal location of the source. These features support the existence of an intrabasinal ridge, containing parts of a Cadomian/
Panafrican basement largely dominated by granitoids (batholiths).
references
Roban, R.D., Ducea, M.N., Maţenco, L., Panaiotu, G.C., Profeta, L., Krézsek, C., Melinte-Dobrinescu, M.C., Anastasiu, N., Dimofte, D., Apotrosoaiei, V. and Francovschi, I. 2020. Lower Cretaceous provenance and sedimentary deposition in the Eastern Carpathians: Inferences
for the evolution of the subducted oceanic domain and its European passive continental
margin. Tectonics, 39, e2019TC005780. http://dx.doi.org/10.1029/2019TC005780
Ştefănescu, M. 1995. Stratigraphy and structure of Cretaceous and Paleogene flysch deposits between Prahova and Ialomiţa valleys. Romanian Journal of Tectonics and Regional
Geology, 76, 4-49.
the continental hessenreuth
formation (danubian cretaceous
group, baVaria, germany): syntectonic
deposition during late cretaceous
inVersion
Birgit Niebuhr1* | Thomas Pürner2 | Annette E. Götz3 | Frank
Holzförster4 | Markus Wilmsen1
1| Senckenberg Naturhistorische Sammlungen Dresden, Museum für
Mineralogie und Geologie, Königsbrücker Landstraße 159, 01109 Dresden,
Germany; *birgit.niebuhr@senckenberg.de, markus.wilmsen@senckenberg.de
2| Bayerisches Landesamt für Umwelt, 95615 Marktredwitz, Germany;
thomas.puerner@lfu.bayern.de
3| Geozentrum Hannover, 30655 Hannover, Germany; Annette.Goetz@lbeg.
niedersachsen.de
4| GEO-Zentrum an der KTB, 92670 Windischeschenbach, Germany;
holzfoerster@geozentrum-ktb.de
The strata of the Danubian Cretaceous Group reflect dynamic depositional
conditions in a peri-continental setting at the northern margin of the Alpine
Tethys. Related to the rather proximal position close to the Bohemian Massif, sediments of highly variable facies and thickness accumulated, representing continental, marginal marine and neritic settings. Cenomanian–earliest Middle Turonian deposition was largely governed by eustatic sea level
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