Late Aptian palaeoclimatic turnovers and volcanism: Insights from a shallow-marine and continental succession of the Apennine carbonate platform, southern Italy

Interlayering of reliable lithologic indicators of palaeoclimate and High-Resolution Event Stratigraphic (HIRES) correlation of the Civitella Licinio succession with the astrochronologically tuned Mt. Faito reference section of the ApCP bring evidence of rapidly fluctuating hydroclimatic conditions (wet and arid phases) in the short (100 ky) and long (400 ky) eccentricity time band. HIRES and astrochronological age assignment to crucial key markers and humid/arid phases at Civitella Licinio permit to further refine the detailed stratigraphy of the Mt. Faito reference section and to assign the upper S. dinarica acme of the ApCP to a numerical age of 118.55-118.50 My. SEM and EDS analyses document common to abundant windblown volcanic particles (glass shards and sanidine crystals) throughout the Frenelopsis-rich Plattenkalk (~ 118.3 to ~ 118.2 My) and the encasing units, especially in the overlying brackish-lacustrine deposits. Palaeogeographic and palaeoclimatic reconstructions suggest that the pyroclastic material was probably transported by northeasterly trade winds from orogenic volcanic centers located within the Dinaridic-Carpatho-Balkan arc-trench system and have been supplied to the ApCP for a time span of ~ 3 My during the Late Aptian. A preliminary tephrostratigraphic correlation of the Upper Aptian volcaniclastic levels of the ApCP with the bentonite levels of the Vocontian Basin is proposed.