The Valanginian history of the eastern part of the Getic Carbonate Platform (Southern Carpathians,Romania): Evidence for emergence and drowning of the platform |
| |
| Institution: | 1. University of the Balearic Islands, Palma de Majorca, Spain;2. Smithsonian Institution, Washington, DC, United States;3. Sorbonne, Pierre and Marie Curie University, Paris, France;1. Università degli Studi di Milano, Dipartimento di Scienze della Terra “A. Desio”, Milano, Italy;2. Università di Roma “La Sapienza”, Dipartimento di Scienze della Terra, Roma, Italy;1. Université Paris Sud, Laboratoire GEOPS, UMR 8148, Orsay F91405, France;2. CNRS, Orsay F91405, France;3. Institut des Sciences de la Terre, Université de Lausanne, Bâtiment Géopolis, 1015 Lausanne, Switzerland;4. Institut des Dynamiques de la Surface Terrestre, Université de Lausanne, Bâtiment Géopolis, 1015 Lausanne, Switzerland;5. UPMC Univ Paris 06, UMR 7207, CR2P, 4 place Jussieu, 75252 Paris, France;6. UMR–CNRS 7193 ISTeP, Institut des Sciences de la Terre–Paris, Université Pierre et Marie Curie, 4 place Jussieu, 75252 Paris CEDEX 5, France;1. Dipartimento di Scienze della Terra e del Mare, Università di Palermo, Via Archirafi 22, 90123 Palermo, Italy;2. Istituto per l''Ambiente Marino Costiero, Consiglio Nazionale delle Ricerche, Via L. Vaccara 61, 91026 Mazara del Vallo, Italy |
| |
| Abstract: | Lower Cretaceous successions that crop out in the eastern part of the Getic Carbonate Platform (Southern Carpathians, Romania) preserve records of the Valanginian events in different settings of the platform. The integrated sedimentological, biostratigraphical, geochemical and mineralogical analysis of the upper Berriasian–Valanginian successions reveal successive stages in the evolution of the carbonate platform: (a) pre-drowning stage of the shallow-shelf and slope settings of the platform; (b) subaerial exposure and karstification; and (c) incipient flooding and drowning of the carbonate platform. Following the subaerial exposure, starting in the middle early Valanginian, the eastern part of the Getic Carbonate Platform experienced a drowning phase documented by iron oxyhydroxides, phosphate and glaucony mineralized discontinuity surface and glaucony-rich sediments disposed on the discontinuity surface. Recognition of the diachronous intra-Valanginian discontinuity surface within the studied successions is based on clear evidences (facies contrast, depositional and diagenetic features, biostratigraphic and taphonomic data, and geometrical relations). The negative–positive carbon isotope excursion is correlated with the global perturbations of the carbon cycle related to the Valanginian “Weissert” episode, and it is documented for the first time in the shallowest parts of the Getic Carbonate Platform. Tectonic activity and eustatic sea-level fluctuations were most probably the main factors that led to fault-block tilting, local emersion and subsequent drowning of the eastern part of the Getic Carbonate Platform during the Early Cretaceous. We infer that the eastern part of the Getic Carbonate Platform was affected by late Berriasian–early Hauterivian extensional tectonics that could be related to the Neo-Cimmerian movements with effects generally recognized in the northern peri-Tethyan areas. |
| |
| Keywords: | Carbonate Platform Subaerial exposure Drowning unconformity Early Cretaceous Southern Carpathians Romania |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
