LOWER MOLASSE DEPOSITS OF DOFTANA MOLASSE AND SLĂNIC MOLASSE, LOCATED IN EASTERN CARPATHIANS, ROMANIA

• Published in: International Multidisciplinary Scientific GeoConference : SGEM Vol. 17; no. 1.1; pp. 291 - 298
• Main Author: Magdalena, Fechet Roxana
• Format: Conference Proceeding
• Language: English
• Published: Sofia Surveying Geology & Mining Ecology Management (SGEM) 01.01.2017
• Subjects: Area; Bearing; Boundaries; Coastal inlets; Conglomerates; Deposits; Ecological succession; Erosion; Erosion processes; Formations; Geology; Globigerina; Gypsum; Investigations; Lithofacies; Lithology; Mapping; Marl; Plate tectonics; Quarries; Sediment deposits; Sedimentary rocks; Shale; Stratigraphy; Structural members; Synclines; Tributaries; Romania
• ISSN: 1314-2704
• DOI: 10.5593/sgem2017/11

The formations having accumulated during the Upper Burdigalian-Badenian sedimentary cycle following a tectogenetic (Eostiric) paroxysm pertain to the Lower Molasse of the Eastern Carpathians and feature significant lithofacies variations. The formations of this sedimentary cycle in the Slănic Prahova-Aluniş area (Prahova County, Romania) include Molasse-type deposits featuring well-individualised geological formations. Since the formations of this sedimentary cycle are the widest spread in the Slănic-Aluniş area and have had a definite role in building the typical morpho-structural elements of the region and in forming the environment, they have deserved a more detailed mapping, which has brought about new and correct data regarding the stratigraphic suite of the Lower Molasse and the transition from a lithostratigraphic formation to another. A more complete succession of the Variegated Formation is distinguishable on the southern tributaries on the right bank of the Aluniş Creek, where the marl component in the Variegated Formation is well open, lying over the conglomerates at the base of the formation. The Medium-Upper Badenian deposits come in sedimentary continuity over the Variegated Formation and constitute the fill proper of the Slănic Syncline. These deposits cover a wide area in the central part of the Slănic cuvette. They stretch towards west from the Malu Dosului-Plaiul Muscelului geological alignment, where they measure 10 km wide, cross the Slănic Valley, the Vărbilău Valley and the Bertea Valley, and narrow gradually up to a pericline closure south of Bertea commune. One of the few points where the contact between the Globigerina-bearing Tuffs and Marls Formation and the Gypsum and Salt Formation is open is situated in the Piatra Verde quarry on the northern flank of the Slănic Syncline, north-east of Slănic-Băi. The lower border of the Globigerina-bearing Tuffs and Marls Formation is also visible in the opening in the centre of the Piatra Verde quarry, where the full lithological succession of the formation can be seen. It is the most beautiful, complete and informative opening in the Globigerina-bearing Tuffs and Marls Formation of the Eastern Carpathians Badenian. The Radiolaria Shale and the Spiratella Marls are only rarely visible in the Slănic-Aluniş area-or the entire region, for that matter-since, on the one hand, the area is widely covered with recent formations and, on the other hand, these deposits are the latest accumulation of a major sedimentary cycle which has been succeeded by an emersion stage corresponding to the Moldavian Paroxysm, coupled with intense erosion processes.