ABSTRACT The complete and well-studied pelagic carbonate successions from the Umbria-Marche basin (Italy) permit the study of the event-rich stratigraphic interval around the Cretaceous-Paleogene boundary (e.g., Deccan volcanism, boundary impact, Paleocene recovery, and climate). To test the robustness of various proxy records (bulk carbonate δ 13 C, δ 18 O, 87 Sr/ 86 Sr, and Ca, Fe, Sr, and Mn concentrations) inside the Umbria-Marche basin, several stratigraphically equivalent sections were investigated (Bottaccione Gorge, Contessa Highway, Fornaci East quarry, Frontale, Morello, and Petriccio core). Besides the classical Gubbio sections of Bottaccione and Contessa, the new Morello section is put forward as an alternative location for this stratigraphic interval because it is less altered by burial diagenesis. Elemental profiles (Ca, Fe, Sr, Mn) acquired by handheld X-ray fluorescence (pXRF) efficiently provide regional chemostratigraphic and paleoenvironmental information. The Deccan volcanism, the Cretaceous-Paleogene boundary, the characteristic pattern of the Sr/Ca profile across the boundary driven by the extinction and recovery of coccolithophores, and the Dan-C2 hyperthermal event are examples of such recorded paleoenvironmental events. Moreover, cyclostratigraphic analyses of proxies of detrital input (magnetic susceptibility and Fe concentrations) show the imprint in the sedimentary record of a 2.4 m.y. eccentricity minimum around 66.45–66.25 Ma, and suggest that the occurrence of the Dan-C2 hyperthermal event was astronomically paced.

ABSTRACT The Umbria-Marche Apennine range, part of the Northern Apennines of Italy, is a classic example of a fold-and-thrust belt developed at the expense of a formerly rifted, passive continental margin that experienced various degrees of postorogenic extension and/or collapse. This setting comprises the outer zones of the Northern Apennines, a collisional orogen, and their adjacent Adriatic foreland domain, where the effects of superposed deformations are mild to very mild, making it possible to recognize and separate structures produced at different times and to correctly establish their relative chronology and time-space relationships. In this paper, we integrated subsurface data (seismic reflection profiles and well logs) and surface structural field evidence with the aim to reconstruct and refine the structural evolution of these two provinces, the Umbria-Marche Apennine range and adjacent Adriatic foreland, which were subject to repeated pulses of alternating extension and compression. The main outcome of this investigation is that the tectonic evolution of the study area may be effectively described in terms of a deformation history characterized by structural inheritance, where structures emanating from the basement and developed during the pre-orogenic rifting stage were effective in controlling stress localization along faults affecting younger sedimentary cover rocks during the subsequent orogenic and postorogenic events.

The Mesozoic and Paleogene pelagic carbonate rocks of the Northern Apennines have proved to be a fertile source for paleomagnetic research. Investigations of the magnetic properties of the Scaglia limestones illuminated the processes by which they were magnetized. Their directions of remanent magnetization contributed to an understanding of the geodynamic history of Adria as a promontory of the African plate and have been used to refine the Mesozoic part of the African polar wander path. Magnetic stratigraphy in the Umbrian sequence and in similar facies in the southern Alps has established an independent record of geomagnetic polarity history since the Middle Jurassic. Correlation with the record derived from interpretation of oceanic magnetic anomalies mutually confirmed the global nature of the polarity history. This enabled the dating of plate motions and the development of a geomagnetic polarity time scale for the late Mesozoic and Cenozoic.