Quaternary still-stand landforms and relations with flank instability events of the Palinuro Bank (southeastern Tyrrhenian Sea) Salvatore Passaro a, * , Girolamo Milano b , Mario Sprovieri c , Stefano Ruggieri a , Ennio Marsella a a Istituto per l’Ambiente Marino Costiero-Consiglio Nazionale delle Ricerche, Calata Porta di Massa (Interno Porto), 80133 Napoli, Italy b Osservatorio Vesuviano-INGV, Via Diocleziano 328, 80124 Napoli, Italy c IAMC-CNR, Sezione di Capo Granitola, Via del Faro 3, 91021 Campobello di Mazara (Trapani), Italy article info Article history: Available online 19 August 2010 abstract A high-resolution morphological and geological inspection was carried out on the Palinuro Bank (39  30 0 N, 14  48 0 E), a volcanic complex made by several, coalescent volcanic features located on the Cam- panian continental slope (Eastern Tyrrhenian Sea, Italy). A shallow (84 m asl) volcanic edifice, char- acterized by a flat top modelled surface, is present on its central sector. The use of a very high-resolution Digital Terrain Model allowed recognition of the presence of relict morphologies (perhaps notches/inner margins) related to the past sea-level still-stands. Three depth levels of paleo-shorelines markers are located at 90 m, 100 m, and 123 m, respectively. In addiction, the truncated shape of the cone itself, located between 84 m and 130 m, could be interpreted as a tilted marine terrace. Breaks in slope produced by terrace landforms caused oversteepening that could have triggered lateral collapses both on the northern and southern flanks of the Bank, as suggested by the presence of steep slopes (25e40  ) and indicated by acoustic facies on chirp high-resolution mono-channel seismic profiles. The results allow further hypotheses on vertical displacement between the western sector of the Palinuro Bank, where caldera shapes are present, and the central sector, made by shallower volcanic cones. These two sectors also differ in terms of magnetic properties. Ó 2010 Elsevier Ltd and INQUA. All rights reserved. 1. Introduction Flight of terraces in ancient coastlines depends on both the sea- level height at the time of formation and the vertical movement of the area itself. If ancient coastlines are dated, fault activity and general tectonic trends of an area may be clarified by such markers (e.g., Antonioli et al., 2003; Ferranti et al., 2006). Although less common than on-land features, submarine terraces have been reported (e.g., Paduan et al., 2009; Webster et al., 2009). Overall, the difference is due to the complexity of continental shelf evolution, which is ruled by depositional/erosional processes, glacio-eustatic sea-level fluctuations, morphology, tectonic, lithology, sedimen- tology, oceanographic factors and climatic changes (Steinke et al., 2003, and references therein), and from the limited information of bathymetric maps as compared with topographic. Similar to what happens for the continental shelf, shallower seamount tops may exhibit the presence of wave-cut planar surfaces due to still- stands of the global sea-level curve. Seamounts are seafloor elevations rising at least 1000 m (International Hydrographic Organization, 2008), usually characterized by a volcanic or a meta- morphic nature, and their presence usually controls the morphology and sedimentology of the surrounding seafloor (Howe et al., 2006). In contrast to what happens on continental shelves, the morphology of seamount tops is not influenced from allochthonous sediments, with the exception of volcanic and volcano-clastic products, but many factors may complicate the formation (or the preservation) of terraced morphologies, even if they are in suitable bathymetric range settlements. For example, seamounts (particularly when volcanic) are significantly subjected to slope instability, due to the intrinsically stratified nature of volcanic bodies and due to the presence of sensitive layers, water content and compositional changes, presence of hydrothermal vents, and local fault activity. In addiction, the original morphology subjected to the wave action is less extended than on the conti- nental shelf and the emerged coastline sectors. Notwithstanding all of these difficulties, the potential detection of wave-built marine terraces on seamounts is not unachievable, and may allow a seaward extension of the computations of vertical movement of an area by using paleo-shoreline as markers. In November 2007, a multidisciplinary survey was carried out on the Aeolian Seamounts in the Southeast Tyrrhenian Sea by a group of researchers of the IAMC-CNR (Naples), Osservatorio Vesuviano (INGV, * Corresponding author. E-mail address: salvatore.passaro@iamc.cnr.it (S. Passaro). Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint 1040-6182/$ e see front matter Ó 2010 Elsevier Ltd and INQUA. All rights reserved. doi:10.1016/j.quaint.2010.08.006 Quaternary International 232 (2011) 228e237