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We present a geological map at 1:25,000 scale of the Plio-Quaternary L’Aquila-Scoppito intermontane basin (central Italy), which corresponds to the epicentral area of the 6th April 2009 L’Aquila earthquake (Mw: 6.29). The map is derived from geological field surveys at 1:5000 scale and takes into account previously published maps. It is supported by a fine-scale LiDAR digital elevation model, paleontological analyses,14C dating, well log analyses of deep boreholes, and geophysical data interpretation. By taking into account that the remarkable historical and present-day seismicity of the area is the result of its Plio-Quaternary geological evolution, the aim of this study is to produce a fine-scale geological map of the study area through a comprehensive analysis of the occurring Plio-Quaternary synthems and the tectonic processes that are taking place within it. [ABSTRACT FROM PUBLISHER]

We present detailed Messinian paleoenvironmental reconstructions for the Adana Basin based on a multidisciplinary approach that utilizes the fossil content of the Kuzgun and Handere Formations. To reconstruct the paleoenvironmental changes that affected the Adana Basin during the Messinian, we analyzed mollusk, ostracod, planktonic and benthonic foraminifer, and calcareous nannofossil assemblages from 2 stratigraphic sections near Kabasakal village (Adana, southern Turkey). To determine if the environmental changes recognized in the Adana Basin are local or regional, and to understand the extent to which the global changes in oceanic circulation impacted the Mediterranean sedimentary basins, we compare our results with Messinian sections from other locations in the Mediterranean region (northern Italy, southern Italy, Cyprus, Algeria, and southern Turkey). The occurrence of N. humerosa, G. bulloides, G. woodi, N. acostaensis, N. atlantica (planktonic forams), S. multiflora, T. rugosa, P. elongata, C. scitula, L. lipadusensis (ostracods), R. rotaria, A. primus, and A. delicatus (calcareous nannofossils) allows us to constrain the uppermost part of the Kuzgun Formation to the early Messinian. The ostracod assemblages indicate an enclosed marine environment characterized by sporadic local freshwater inputs that decreased the salinity of the basin. In contrast, in the late Messinian Handere Formation, the presence of Paratethyan ostracods pertaining to the Loxoconcha mülleri zone and to the Loxocorniculina djafarovi zone in the Handere Formation indicates the occurrence of the Messinian brackish water Lago-Mare event in the Adana Basin, which occurred throughout the Mediterranean between 5.60 and 5.33 Ma. [ABSTRACT FROM AUTHOR]

Study of the tectonically active L'Aquila Basin offers new insights into both the creation of the extensional intermontane basins of the central Apennines of Italy and their tectono-sedimentary evolution through time. The combination of large mammal remains, ostracods, molluscs, Mousterian tools, and 14C dating allows better definition of the onset and stratigraphic evolution of the L'Aquila Basin. Interpretation of a seismic reflection profile and well-log data allow evaluation of the subsurface setting of this sedimentary basin and its tectono-sedimentary evolution. The occurrence of a wedge-shaped seismic unit at the base of the basin sedimentary succession defines the first phase of basin fill during a late Piacenzian-Gelasian synrift stage. Activity along the main fault of the extensional fault system responsible for the onset and subsequent development of the western sector of the L'Aquila Basin (L'Aquila-Scoppito subbasin) migrated from southwest to northeast, reaching the presently active Mount Pettino normal fault only in the late Pleistocene-Holocene. The onset of sedimentation in the L'Aquila Basin was synchronous with the onset in the Tiberino Basin, and so the idea that these extensional intermontane basins become progressively younger from the Tyrrhenian toward the Adriatic side of the central Apennines is rejected. In the northern and central Apennines, only two major syndepositional extensional domains can be recognized: a late Miocene rifting area, which includes all the late Miocene extensional basins in Tuscany, and a late Pliocene to earliest Pleistocene rifting area, which possibly includes all the intermontane basins from the Tiberino Basin to the Sulmona Basin. The different time gaps between compressional and extensional deformation at any given locality in the central Apennines could indicate a partial decoupling of processes responsible for the migration of shortening and extension toward the foreland. Diachroneity between the eastward migration of shortening in the foreland and extension in the inner part of the orogen supports the notion that the central Apennines were created as a result of a partially decoupled collision zone. Study of the onset of the central Apennine extensional intermontane basins, together with their seismic activity, indicates that the central Apennine postorogenic extensional domain represents an archive of ~3 m.y. of continued crustal extension. These findings help to refine models of the long-term extensional rate of the central Apennines, and they provide a basis for more reliable seismotectonic models for one of the most seismically active sectors of the central Mediterranean area. [ABSTRACT FROM AUTHOR]

A gigantic cascade of Atlantic waters, filling the deep desiccated Mediterranean basin at the beginning of the Pliocene, has commonly been envisaged to end the Messinian Salinity Crisis (MSC). The Mediterranean lowstand during its final “Lago-Mare” phase, however, has long been subject to major controversy and has recently been seriously questioned again. Here, we present high-resolution ostracod distribution patterns of the MSC successions in the Black Sea basin (Zheleznyi Rog section; Russia) and the Mediterranean (Cuevas del Almanzora section; Spain) to study the origin and migration history of the Lago-Mare ostracods. We conclude that two major phases of faunal migration have taken place in the Messinian. The first phase corresponds to the Maeotian–Pontian boundary interval (~ 6.1–6.0 Ma) of the Paratethys, where mainly Pannonian species suddenly invaded the Black Sea region. The second migration event corresponds to the Lago-Mare phase of the Mediterranean when first (5.55–5.47 Ma) some opportunistic taxa (species of Cyprideis and Loxoconcha genera) and then (5.40–5.33 Ma) a more diverse assemblage of Paratethyan species occupied the entire Mediterranean region. The Spanish ostracod assemblages show a high percentage of Paratethyan (Pontian) ostracods, in agreement with previously studied Italian Lago-Mare sections. The similar palaeoenvironmental changes that developed roughly synchronously in the western and central Mediterranean marginal basins provide more evidence for intrabasinal exchange at high water level during the final stage of the Lago-Mare phase. This indicates that the Mediterranean in the latest Messinian was full of water (comparable to the present Caspian Sea) and that the Zanclean deluge, if happened, only surged some tens, up to few hundred metres, into the Mediterranean. [ABSTRACT FROM AUTHOR]

Abstract: Late Miocene brackish ostracods and molluscs collected in three Italian basins show noticeable differences in their taxonomic composition, despite their capability of dispersing across wide geographic areas. In the Venetian-Friulian Basin (northern Italy), the upper Tortonian sediments contain oligotypic ostracod assemblages including Hemicyprideis dacica dacica, Hemicytheria pejinovicensis, and Loxoconcha cf. L. josephi and few gastropods referable to Planorbidae and Stenothyroides, which are typical of the central Paratethys. In central Italy, the brackish ostracods and molluscs recovered from upper Tortonian-lower Messinian deposits from four Tuscan basins (Volterra-Radicondoli, Velona, Baccinello-Cinigiano, and Valdelsa) display high affinity at a generic level but strong endemicity at a specific level. At Cessaniti (southern Italy), the upper Tortonian unit contains oligotypic brackish ostracods and molluscs: Mediocytherideis (Sylvestra) posterobursa, Cyprideis ruggierii, Loxoconcha cf. L. biformata, and Zonocypris membranae quadricella characterise the ostracod fauna, while Granulolabium bicinctum and Hydrobia frauenfeldi are the dominant molluscs. The recovered ostracods have a strong affinity with brackish species from central and eastern Palaeo-Mediterranean areas, whereas the molluscs present a Paratethyan origin. Despite the fact that the basins are all brackish and partly coeval, the systematics of these assemblages highlights the absence of common species among the three studied areas. Geochemical analyses (stable isotopes and trace elements) are performed on ostracods, and 87Sr/86Sr ratios are established in molluscs and echinoids. The results suggest brackish environments with different compositions and origins of solutes in the three different areas. The Tuscan basins are characterised by brackish waters, with NaCl-enriched waters coming from aquifers of Triassic evaporite bedrock. The brackish deposits of the Venetian-Friulian Basin and Cessaniti are true marginal marine environments, although the northern basin may have been influenced by both the Paratethyan Sava Basin and the northern portion of the Palaeo-Mediterranean water bodies. [Copyright &y& Elsevier]

Paleoenvironmental and paleoclimate changes that occurred during the late post-evaporitic stage of the Mediterranean Basin in the Messinian foreland domain of the Adriatic region offer a new perspective on the relationship between orbital forcing and climate response. The magnetic susceptibility record of the Fonte dei Pulcini A section (Maiella Mountains, Italy) allows us to orbitally tune the record between 5.394 and 5.336 Ma and to temporally constrain the paleoenvironmental and paleoclimate changes evidenced by quantitative paleontological (palynomorphs, ostracods, and calcareous nannofossils), stable isotope (δ18O and δ13C), and X-ray diffraction (XRD) analyses. The base of the Fonte dei Pulcini A section is characterized by Paratethyan ostracods and dinocysts, which point to the late Messinian Lago-Mare biofacies (Loxocorniculina djafarovi zone) of the Mediterranean Messinian stratigraphy. From paleontological and geochemical (δ18O) analyses, there is no evidence of a marine incursion in the Fonte dei Pulcini A section. The major changes in terms of paleodepth, paleosalinity, evaporation versus precipitation, aridity versus humidity, and reworking processes occurred in the upper part of the Fonte dei Pulcini A section, during the last Messinian insolation cycle (i-cycle 511/512), which is characterized by high-amplitude oscillations. In contrast, the lower part of the Fonte dei Pulcini A section, which was deposited during relatively low-amplitude insolation cycles, is characterized by more stable environmental conditions. Comparing summer insolation with the paleoenvironmental changes at the Fonte dei Pulcini A section, we identify delays of several thousands of years between orbital forcing and climate response. [ABSTRACT FROM AUTHOR]