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Facies succession of the Oligocene terrigenous sequences from a seccar of Piedmont Tertiary Basin (between Ovada and Cassinelle, Alessandria) are here described and their significance discussed. The palaeogeographic evolution of the area results to be controlled by a synsedimentary tectonics. In the Early Oligocene, a generalised vertical mobility affected the region which, as a conse­quence, was splitted in some blocks with a differential tectonic behaviour by tensive lineaments; that is testified by a widesprcad continental facies characteristic of a high energy environment (lower pare of "Formazione di Molare"). Successively, ali the area subsided, and the sea transgressed over it (upper part of "Formazione di Molare"). During the Late Oligocene subsidence acted differentially along synse­dimentary faults and the deeper portions are individuated; which became location of relatively deep marine deposition ("Marne di Rigoroso"). The intense tectonic activity was responsible for the deposition of large conglomeratic and arenaceous bodies interbedded within the hemipelagic sequences (in the areas with precocious and intense drowning).

We describe here a new bony fish assemblage collected from a fossiliferous outcrop located in Perarolo, Berici Hills, Venetian Southern Alps. The fossiliferous deposits pertain to the Rupelian (lower Oligocene) Castelgomberto Calcarenite and are indicative of a tropical marine shallow water setting associated with coral reefs. The assemblage is characterized by diminutive putative cryptobenthic fishes, including a single goby (family Gobiidae) and several cardinalfishes of the subfamily Pseudamiinae (family Apogonidae). Furthermore, a new apogonine of the extinct tribe †Eoapogonini, a new butterflyfish (family Chaetodontidae), and an indeterminate viviparous brotula belonging to the ophidiiform family Dinematichthyidae, are also present, and likely represented part of the epibenthic community. Some of the taxa described herein are among the first occurrences within their respective lineages in the fossil record. The Perarolo taxa document the first Oligocene coral reef fish assemblage known to date. Four taxa are described as new: †Arconiapogon deangelii gen. et sp. n., †Chaetodon (Blumchaetodon) wattsi subgen. et sp. n., †Oligopseudamia iancurtisi gen. et sp. n., and †Oniketia akihitoi gen. et sp. n. [ABSTRACT FROM AUTHOR]

Here we describe a new bony fish assemblage collected from a fossiliferous outcrop located in Perarolo, Berici Hills, Venetian southern Alps. The fossiliferous deposits pertain to the Rupelian (lower Oligocene) Castelgomberto Calcarenite and are indicative of a tropical marine shallow water setting associated with coral reefs. The assemblage is characterized by diminutive putative cryptobenthic fishes, including a single goby (family Gobiidae) and several cardinalfishes of the subfamily Pseudmiinae (family Apogonidae. Furthermore, a new apogonine of the extinct tribe †Eoapogonini, a new butteflyfish (family Chaetodontidae), and an indeterminate viviparous brotula belonging to the ophidiiform family Dinematichthyidae, are also present, and likely represented part of the epibenthic community. Some of the taxa described herein are among the first occurrences for their respective lineages in the fossil record. The Perarolo taxa document the first Oligocene coral reef fish assemblage known to date. Four taxa are described as new: †Arconiapogon deangelii gen. et sp. n., †Chaetodon (Blumchaetodon) wattsi subgen. et sp. n., †Oligopseudamia iancurtisi gen. et sp. n., and †Oniketia akihitoi gen. et sp. n.

The marine Oligocene deposits of Pakistan are exposed in the Baluchistan and Lower Indus Basins. The Baluchistan Basin deposits are referred to the Khojak Formation of Makran Group. They represent three planktic foraminiferal zones, the Globigerina ampliapertura Zone, G. ciperoensis Zone and Globorotalia kugleri Zone, corresponding to Early, Middle and Late Oligocene. The Lower Indus Basin deposits of Sind include the Kirthar and Nari Formations. On the basis of the larger Foraminifera these deposits are divided into Nummulites fichteli Zone (Early Oligocene), N. fichteli/Lepidocyclina (E.) dilatata Zone (Mid. Oligocene), and L. dilatata Zone (Late Oligocene). The Oligocene deposits are absent in the Upper Indus Basin due to the orogenic movement which took place at the end of the Eocene and continued in the Oligocene.

The Palaeogene deposits in the Swiss Molasse Basin, the intermediate Swiss Jura and the adjacent southern Upper Rhine Graben represent an excellent case study for interbasinal sedimentary and palaeogeographic relationships. The topographic and geologic complexity of the area led to an accumulation of local stratigraphic terms during nearly 200 years of research activity, necessitating a simplification of the lithostratigraphic framework. Additionally, the extension of the investigated area over two historically shifting language areas and the absence of a standardised supraregional lithostratigraphy adds to complexity of the situation. In revising and grouping around 200 multilingual Palaeogene lithostratigraphic terms and spellings from the northern Jura and the southern Upper Rhine Graben that accumulated since 1821 we propose a concise standardised framework of 10 formations (6 new and/or emended) and 6 new members. It avoids the confusing multitude of historic “formation” names and stratigraphic ambiguity like the “Septarienton”, “Molasse alsacienne” or the “Cyrenenmergel”. The new formations include the Turckheim Formation (formerly “Steingang”, “Conglomérats côtiers”), the Rossemaison Formation (formerly “Terre jaune”, “Gelberde”), the Pulversheim Formation (formerly “Melettaschichten”) and the Wahlebach Formation (formerly “Cyrenenmergel”, partim “Molasse alsacienne”). The Wallau and Hochberg subformations are emended and elevated to formation status. For all discussed units except the Sidérolithique new reference and/or type sections are provided and illustrated. This new framework is put in context to recent stratigraphic schemes from adjacent areas in the Upper Rhine Graben, proposing status changes and emendations for existing units (e.g. Wallau-Subformation emended to Wallau Formation). To illustrate the former complexity and the proposed standardisation in the larger area, we applied the lithostratigraphic context to 9 palaeogeographic maps. New heavy mineral data from the Delémont Basin complements the scarce regional information and is discussed in relation to Palaeogene tectonosedimentary context of the North Alpine Foreland Basin and the southern Upper Rhine Graben.

The Palaeogene deposits in the Swiss Molasse Basin, the intermediate Swiss Jura and the adjacent southern Upper Rhine Graben represent an excellent case study for interbasinal sedimentary and palaeogeographic relationships. The topographic and geologic complexity of the area led to an accumulation of local stratigraphic terms during nearly 200 years of research activity, necessitating a simplification of the lithostratigraphic framework. Additionally, the extension of the investigated area over two historically shifting language areas and the absence of a standardised supraregional lithostratigraphy adds to complexity of the situation. In revising and grouping around 200 multilingual Palaeogene lithostratigraphic terms and spellings from the northern Jura and the southern Upper Rhine Graben that accumulated since 1821 we propose a concise standardised framework of 10 formations (6 new and/or emended) and 6 new members. It avoids the confusing multitude of historic "formation" names and stratigraphic ambiguity like the "Septarienton", "Molasse alsacienne" or the "Cyrenenmergel". The new formations include the Turckheim Formation (formerly "Steingang", "Conglomérats côtiers"), the Rossemaison Formation (formerly "Terre jaune", "Gelberde"), the Pulversheim Formation (formerly "Melettaschichten") and the Wahlebach Formation (formerly "Cyrenenmergel", partim "Molasse alsacienne"). The Wallau and Hochberg subformations are emended and elevated to formation status. For all discussed units except the Sidérolithique new reference and/or type sections are provided and illustrated. This new framework is put in context to recent stratigraphic schemes from adjacent areas in the Upper Rhine Graben, proposing status changes and emendations for existing units (e.g. Wallau-Subformation emended to Wallau Formation). To illustrate the former complexity and the proposed standardisation in the larger area, we applied the lithostratigraphic context to 9 palaeogeographic maps. New heavy mineral data from the Delémont Basin complements the scarce regional information and is discussed in relation to Palaeogene tectonosedimentary context of the North Alpine Foreland Basin and the southern Upper Rhine Graben. [ABSTRACT FROM AUTHOR]

A new species of the genus Lithophyllum (Lithophyllum ippolitoi) was discovered in the Oligocene section of Toleto (Molare Formation, Tertiary Piedmont Basin). The holotype overgrows a coral colony, and is characterised by morphological features and dimensions of cells that are clearly different from those of the other recorded species of Lithophyllum.

The main features of the Oligocene Molare Fm. cropping out in the "Alto Monferrato" area (Piedmont Tertiary Basin, Northern Italy) are briefly summarized. Lithofacies associations and sandstone composition allow to outline the initial stage of the PTB history in the examined area.

This work reconstructs a now completely eroded late Eocene to earliest Oligocene carbonate factory of Northern Italy, through the analysis of a carbonate deep-water-fan sequence (Ternate-Travedona Formation) and the limestone detritus dispersed into the late Oligocene clastic-wedge of the Gonfolite Lombarda Group. Textural characteristics and skeletal assemblages of the Gonfolite pebbles were studied and compared to those of the Ternate-Travedona Formation. The same skeletal assemblage and the same taxa were found in samples from both areas, suggesting their common origin. Whereas the Ternate-Travedona Formation skeletal grains were reworked during transport, the Gonfolite Lombarda Group pure-limestone pebbles are pristine fragments of the carbonate platform, that was uplifted and eroded from the late Eocene to the early Oligocene. Using both these sources of information it was possible to reconstruct the late Eocene environment and its facies distribution. The areas undergoing high hydrodynamic energy were dominated by free-living coralline-algal branches, rhodoliths and larger thick-tested benthic foraminifera. A coralline framework, associated with thin-tested benthic foraminifera and boxwork rhodoliths, was present in slightly deeper and sheltered environments. Episodic debris flows, mainly triggered by river floods, supplied the sub-marine fan of the Ternate-Travedona Formation. These events were able to down-cut through the narrow platform and rip off large fragments of the substrate. River runoff probably also supplied large quantities of organic matter, leading to local oxygen-depletion and preservation of organic matter. The combined stressful effects of bottom instability and riverine discharge probably excluded corals from the association. The integrated study of the Ternate-Travedona Formation, and of the limestone pebbles in the Gonfolite Group, have enabled the reconstruction of this otherwise lost Eocene carbonate factory.

This work reconstructs a now completely eroded late Eocene to earliest Oligocene carbonate factory of Northern Italy, through the analysis of a carbonate deep-water-fan sequence (Ternate-Travedona Formation) and the limestone detritus dispersed into the late Oligocene clastic-wedge of the Gonfolite Lombarda Group. Textural characteristics and skeletal assemblages of the Gonfolite pebbles were studied and compared to those of the Ternate-Travedona Formation. The same skeletal assemblage and the same taxa were found in samples from both areas, suggesting their common origin. Whereas the Ternate-Travedona Formation skeletal grains were reworked during transport, the Gonfolite Lombarda Group pure-limestone pebbles are pristine fragments of the carbonate platform, that was uplifted and eroded from the late Eocene to the early Oligocene. Using both these sources of information it was possible to reconstruct the late Eocene environment and its facies distribution. The areas undergoing high hydrodynamic energy were dominated by free-living coralline-algal branches, rhodoliths and larger thick-tested benthic foraminifera. A coralline framework, associated with thin-tested benthic foraminifera and boxwork rhodoliths, was present in slightly deeper and sheltered environments. Episodic debris flows, mainly triggered by river floods, supplied the sub-marine fan of the Ternate-Travedona Formation. These events were able to down-cut through the narrow platform and rip off large fragments of the substrate. River runoff probably also supplied large quantities of organic matter, leading to local oxygen-depletion and preservation of organic matter. The combined stressful effects of bottom instability and riverine discharge probably excluded corals from the association. The integrated study of the Ternate-Travedona Formation, and of the limestone pebbles in the Gonfolite Group, have enabled the reconstruction of this otherwise lost Eocene carbonate factory. [ABSTRACT FROM AUTHOR]

Based on palaeobotanical material preserved at the University of Genoa, Italy (DIP.TE.RIS.), a revision of the Early Oligocene flora of Santa Giustina, as well as the 1916 monograph of Principi, was undertaken. It is shown that apart from members of the Lauraceae family, Eotrigonobalanus furcinervis and Sloanea olmediaefolia were dominant in the flora, which was mainly composed of warmth-demanding species. The site is primarily characterized by remnants of the vegetation developed under warm and moist climate and abundant water supply. A few additional plants from the neighboring zonal vegetation are also present. The flora is quite reminiscent of that of the Tard Clay Formation, part of the Inner Carpathian Region, providing a proven link to the floristic relationships of these areas. Up to the Pre-Neogene, the Inner Carpathian Region and the surrounding Alpine-Carpathian-Dinaric Region was composed of a composite terrane that 1) existed independently from Stable Europe, and, 2) had a much more southerly position than today. This terrane collage was sharply bordered from all directions except west, as is supported by new evidences of the floristic affinities with the Santa Giustina flora.

Since the '60s geologists discussed if the Tuscan Nappe includes the Macigno, the Mt. Modino Sandstone and the olistostromes interposed between these two clastic wedges or instead the foredeep deposits of the Tuscan Nappe is the Macigno and, therefore, the Mt. Modino Sandstone sedimented in a distinct basin and belongs to a different tectonic unit. One of the main difficulties to unravel the Macigno-Mt. Modino Sandstone relationships is the absence of continuous biostratigraphic records, helpful to date these formations and the underlying units. To fill this gap, a quantitative biostratigraphical analysis of calcareous nannofossils was performed on a large number of smear slides. The results confirm the stratigraphic continuity between the Tuscan Shale and the Macigno, and prove the stratigraphic continuity between the Fiumalbo Shale, the Marmoreto Marl and the Mt. Modino Sandstone (Mt. Modino Unit auctt.), supporting the tectonic superposition of the Mt. Modino Unit onto the Tuscan Nappe. In fact, the upper portion of the Tuscan Nappe ranges from the Late Eocene (MNP19/20) to the lower Miocene (MNN1c) and the Tuscan Shale-Macigno boundary lies within the upper Rupelian-Chattian (MNP24-MNP25a), whilst the sampled part of the Mt. Modino Unit spans in age the middle Eocene-lower Miocene (MNP15-MNN1c), and the Fiumalbo Shale-Marmoreto Marl and Marmoreto Marl-Mt. Modino Sandstone boundaries lie within the Rupelian (MNP23) and the uppermost Chattian (MNP25b-MNN1a).

A continuous late Eocene through Oligocene carbonate sequence was recovered at Ocean Drilling Program (ODP) Site 1218 in the paleo-equatorial Pacific Ocean. The preservation history of selected calcareous nannofossil species across the Eocene/Oligocene (E/O) boundary is presented together with late Eocene and Oligocene calcareous nannofossil biochronology. The astronomically calibrated timescale of Pälike et al. (2006) is used here. Across the E/O boundary, placolith preservation is controlled by variation in carbonate content. Taxa less prone to dissolution are Reticulofenestra umbilicus, Coccolithus pelagicus, Ericsonia formosa and Dictyococites bisectus, while Cyclicargolithus floridanus is more susceptible to dissolution. A biochronologic framework has been established for the following taxa: the highest occurrences (HO) of Discoaster barbadiensis (34.773 Ma), D. saipanensis (34.435 Ma), E. formosa (32.919 Ma), R. umbilicus (32.021 Ma), Sphenolithus predistentus (26.928 Ma), S. distentus (26.812 Ma), and S. ciperoensis (24.432 Ma), and the lowest occurrences (LO) of S. distentus (29.997 Ma) and S. ciperoensis (27.142 Ma). The first consistent appearance of Triquetrorhabdulus carinatus occurs at 26.556 Ma, while the onset of the peak interval of T. carinatus was determined at 24.669 Ma. Biochronological comparisons are made with other sites from the Atlantic Ocean. A Triquetrorhabdulus morphotype, labeled as T. aff. carinatus, was recorded for the first time in the studied sediments, and precedes the LO of T. carinatus by ~ 0.7 Myr. Its stratigraphic range has a duration of about 3.3 Myr. T. aff. carinatus disappears concomitantly with the beginning of a sharp increase in abundance of T. carinatus.

A small collection of echinoids from the Eastern Desert of Jordan includes the species Clypeaster biarritzensis, Amphiope? sp., Echinolampas cherichirensis, and Eupatagus meslei. This fauna closely resembles faunas of early Oligocene age from North Africa. The presence of the associated foraminifera Nummulites intermedius and N. fichteli dates the upper portion of the Wadi Shallala Formation exposed in the area of Wadi Al Ghadaf as early Oligocene (Rupelian), younger than the generally accepted middle (Bartonian) to late Eocene (Priabonian) age of this formation. The presence of rocks of this age in Jordan along what was probably the southern margin of the Tethyan Seaway is evidence that communication between the eastern and western provinces of the Western Tethys Region still existed in this area at this time.

Leaves of Sloanea elliptica (Andreánszky) Z. Kvaèek & Hably and S. peolai (Principi) Hably, Tamás & Cioppi with preserved organic structures were found during the study of Principi’s collection from the Oligocene flora of Santa Giustina. Fossil leaves of Sloanea elliptica have so far been recorded exclusively from the Palaeogene Basin of the Inner Carpathian Region, i.e. from the Lower Oligocene strata of Hungary and Slovenia, whereas S. peolai has been described from a single locality, Chiavon in Italy. Organic structure of S. peolai hitherto has not been recorded. The mass occurrence of Sloanea elliptica in the fossil assemblage of Santa Giustina indicates that its area was much more extensive than it was presumed. It was a characteristic element mainly of Oligocene floras, and even predominated them. This is the first record of the co-occurrence of two Sloanea species described on the basis of leaf remains. During the study 6 types and more than 30 illustrated specimens published in Principi's monograph were revised and identified as S. elliptica.