Scontrone (central Italy), signs of a 9‐million‐year‐old tragedy

The fossilierous bonebeds of Scontrone (Abruzzo region, central Italy) are preserved in tidal‐flat aeolian calcarenites at the base of the Lithothamnion Limestone, a Miocene carbonate ramp widespread in the central‐southern Apennines. The site bears evidence of a catastrophic event at 9 Ma. Reported are the results of the palaeobiological and taphonomic analysis conducted on the rich vertebrate assemblage, particularly on the remains of Hoplitomeryx (Mammalia, Artiodactyla, Ruminantia), recovered from the so‐called Scontrone calcarenites between 1992 and 2012. This is the first taphonomic study of a Late Miocene continental bone assemblage preserved in coastal deposits. The bones are not in primary context. They were likely exhumed during the initial phase of a marine transgression after a period of primary ‘storage’ within a possibly flood‐generated deposit in an estuarine environment. The mortality patterns indicate that the carcasses accumulated in a short time (within a year). The bones of the disarticulated skeletons were then removed, broken in a dry and brittle state, scattered over wide carbonate ramps along an arid to semi‐arid, wind‐exposed coastline and eventually buried again in aeolian calcarenites that drape transgressive tidal‐flat creek deposits. The analysis also reveals that hoplitomerycids were possibly seasonal reproducers and that the land they inhabited, the so‐called Apulia Platform, was probably swept by sudden, disastrous, storm‐supplied flash floods.     

The age of immigration of the vertebrate faunas found at Gargano (Apulia,Italy) and Scontrone (l’Aquila,Italy)

Recently a discussion is taking place about the Scontrone (l’Aquila) and Gargano (Apulia, Italy) mammal faunas and the age of their immigration. Mazza and Rustioni (2008) dated the Scontrone mammal fossils as Tortonian on the basis of their position in the Lithothamnium Limestone and came to the conclusion that some elements of the Scontrone and Gargano faunas must have colonised the area in Oligocene or Early Miocene times. Van den Hoek Ostende et al. (2009) disagreed with this interpretation and suggested a Late Miocene (10 Ma) age for the time of immigration. We think the arguments to place Scontrone in the Tortonian are not convincing. An analysis of the potential ancestors of each of the Gargano faunal components shows that a Messinian age for the immigration is fully compatible with the distribution of these ancestors in the European Miocene.     

Strontium stratigraphy of the upper Miocene Lithothamnion Limestone in the Majella Mountain,central Italy,and its palaeoenvironmental implications

The ⁸⁷Sr/⁸⁶Sr isotope ratio has been widely used as a physical tool to date and correlate carbonate successions due to the long Sr residence time in comparison with the ocean mixing time. If this method works on oceanic successions, marginal basins may show different Sr isotope records in comparison with the coeval ocean one due to sea‐level variations, continental run‐off and restricted water exchanges. In this work, we present the ⁸⁷Sr/⁸⁶Sr isotope record of the upper Miocene carbonate ramp of the Lithothamnion Limestone (Majella Mountain, central Apennines), as an example of the onset of restricted water exchanges between a marginal basin and the ocean water masses. The overall latemost Tortonian–early Messinian Sr isotope record of the Lithothamnion Limestone fits below the global reference line. This deviation has been interpreted as due to the strong control that freshwater input and enhanced continental run‐off, linked to the migration of the Apennine accretionary wedge and foredeep system, have had on the central Adriatic water chemistry. These results imply that an accurate oceanographic and geodynamic framework along with diagenetic overprint investigation has to be taken into consideration prior to apply SIS on carbonate successions on marginal basins, even when facies analyses indicate fully marine conditions. This seems to be the case for the upper Miocene Central Mediterranean carbonate successions, but may have more general validity and be extended to other recent or past marginal basins.     

New discoveries on the giant hedgehog Deinogalerix from the Miocene of Gargano (Apulia,Italy)

During the Miocene, the Abruzzo/Apulia region (Italy), isolated from the continent, was the theatre of the evolution of a vertebrate ecosystem in insular context. During the Late Miocene, the protagonists of this ecosystem called “Mikrotia fauna” show a high endemic speciation level, presenting spectacular giant and dwarf species of mammals and birds. Deinogalerix is one of the most uncommon forms of this peculiar fauna. It is the largest Galericinae that ever lived. From Gargano (Apulia, Italy) deposits (also called “Terre Rosse”), Deinogalerix has been, since its discovery in the 1970s’, the subject of two publications in which various morphotypes were described. Its presence is also attested at Scontrone (Abruzzo, Italy). In 2005, the new Miocene fissure “Mikrotia 013” (M013) was found in the Gargano area at Cava Dell’Erba by a team of the Università degli studi di Torino. The study of the micromammals, and in particular the presence of an archaic form of Mikrotia, attests that M013 is the oldest fissure known to date. All the Deinogalerix remains come from the smallest morphotype ever found. The morphological features (other than size) allow us to describe the new species Deinogalerix masinii. It presents a large variability of dental and mandibular features expressed in mosaic patterns within the material: the robustness of the upper and lower P3 and P4, and the characteristic trigonid of m1 of the genus; the archaic morphology of the maxilla and the mandible; the abrading pattern of the teeth are unique for Deinogalerix. These new remains allow us to update the knowledge of Deinogalerix. The suit of characters testified that D. masinii nov. sp. is an archaic form on the evolutionary trend toward the most derived representatives of the genus. The affinities of Deinogalerix with the Parasorex group are confirmed, but the time of immigration in Gargano remains debated.     

Foraminiferal biozonation,biostratigraphy and trans-basinal correlation of the Oligo-Miocene Qom Formation,Iran (northeastern margin of the Tethyan Seaway)

During the Rupelian–Burdigalian (early Oligocene–early Miocene), the Qom Formation was deposited along the northeastern margin of the Tethyan Seaway in the Sanandaj–Sirjan, Urumieh–Dokhtar, and Central Iran basins. The biostratigraphic data from a total of 1152 thin sections from 10 outcrop sections along over 1000 km of the Tethyan Seaway margin are presented. A larger benthic foraminiferal (LBF) biozonation, consisting of five biozones, is proposed for dating the Rupelian–Burdigalian Qom Formation. It is correlated with global planktonic zones, LBF zones, southeastern Asian “Letter Stages”, shallow benthic foraminiferal zones (SB-zones) of southern European basins, and newly revised zones of the Asmari Formation in southwestern Iran. This biozonation subdivides the Rupelian stage into “early Rupelian” and “late Rupelian”, based on the first appearances of lepidocyclinids in the latter one. The early Rupelian strata are characterized by the presence of Nummulites without lepidocyclinids which are reported merely from southwestern and southern Kashan, where the thickest Rupelian deposits of the Qom Formation are recorded. The basal layers of the Qom Formation in southeasternmost outcrops (northwestern Jazmurian Lake) are late Rupelian in age based on the co-occurrence of lepidocyclinids and Nummulites spp. By comparison of the well-documented transgression of the Tethyan Seaway over the Iranian plate (from southeast to northwest) and the limitation of all reported early Rupelian strata of the Qom Formation to southwestern and southern Kashan, the following scenarios can be supposed: 1) the oldest deposits could be deposited in southeastern Iran, but they have not been reported, yet; 2) during early Rupelian, there was a transgression from the Zagros Basin to southwestern and southern Kashan areas, then the transgression progressed both northwestward and southeastward.     

Lower Miocene stratigraphy along the Panama Canal and its bearing on the Central American Peninsula

Before the formation of the Central American Isthmus, there was a Central American Peninsula. Here we show that southern Central America existed as a peninsula as early as 19 Ma, based on new lithostratigraphic, biostratigraphic and strontium chemostratigraphic analyses of the formations exposed along the Gaillard Cut of the Panama Canal. Land mammals found in the Miocene Cucaracha Formation have similar body sizes to conspecific taxa in North America, indicating that there existed a terrestrial connection with North America that allowed gene flow between populations during this time. How long did this peninsula last? The answer hinges on the outcome of a stratigraphic dispute: To wit, is the terrestrial Cucaracha Formation older or younger than the marine La Boca Formation? Previous stratigraphic studies of the Panama Canal Basin have suggested that the Cucaracha Formation lies stratigraphically between the shallow-marine Culebra Formation and the shallow-to-upper-bathyal La Boca Formation, the latter containing the Emperador Limestone. If the La Boca Formation is younger than the Cucaracha Formation, as many think, then the peninsula was short-lived (1–2 m.y.), having been submerged in part by the transgression represented by the overlying La Boca Formation. On the other hand, our data support the view that the La Boca Formation is older than the Cucaracha Formation. Strontium dating shows that the La Boca Formation is older (23.07 to 20.62 Ma) than both the Culebra (19.83–19.12 Ma) and Cucaracha (Hemingfordian to Barstovian North American Land Mammal Ages; 19–14 Ma) formations. The Emperador Limestone is also older (21.24–20.99 Ma) than the Culebra and Cucaracha formations. What has been called the “La Boca Formation” (with the Emperador Limestone), is re-interpreted here as being the lower part of the Culebra Formation. Our new data sets demonstrate that the main axis of the volcanic arc in southern Central America more than likely existed as a peninsula connected to northern Central America and North America for much of the Miocene, which has profound implications for our understanding of the tectonic, climatic, oceanographic and biogeographic history related to the formation of the Isthmus of Panama.     

The Scontrone turtles – A new insular testudinoid fauna from the late Miocene of the Central Mediterranean

We here describe a small turtle assemblage originating from the early Tortonian (late Miocene) palaeoisland of Scontrone, central Italy, a locality previously known mostly for its endemic mammals and giant birds, which were otherwise shared only with the Gargano localities, another fossiliferous area belonging to the same palaeobioprovince. The fossil turtle remains from Scontrone are referred to the geoemydid Mauremys sp. and a so far unidentified large-sized testudinid. The biogeographic origins of the Scontrone insular chelonians are discussed. The Scontrone geoemydid adds to the known occurrences of Mauremys in the late Miocene of the Mediterranean. The Scontrone large tortoise represents the oldest known Mediterranean insular testudinid, predating significantly the well-known Quaternary endemic island tortoises of the area.     

Les ostracodes du Néogène supérieur du littoral nord-ouest marocain entre Tanger et Asilah

Ostracodes populations have been studied in 19 samples from the upper Neogene of the Atlantic coast of NW of Morocco, between Tangier and Asilah. One hundred and two species belonging to 53 genera have been indentified. Analysis of the species assemblages allowed to reconstruct the palaeoenvironmental evolution of these deposits. This begins with the transgression of the upper Tortonian which corresponds to a relatively deep circalittoral environment. The series continues by deposits showing a general regressive character, punctuated by few transgressives pulses. Shallowing starts at the end of the upper Tortonian with the deposition of calcarenites in massive banks, in an infralittoral exposed environment. This facies pass towards the top to a detrital facies, assigned to the Messinian and deposited under high energy conditions in a shallow-marine environment. The lower Pliocene transgression shows a more generalized character. The maximum deepening corresponds to the grey clay facies deposited in the external infralittoral environment, relatively protected and rich in phytal biotopes. The more recent deposits are shallower, from coastal environments, and show a more limited extension.     

Encrusting micro-organisms and microbial structures in Upper Jurassic limestones from the Southern Carpathians (Romania)

Late Jurassic–Early Cretaceous ?tramberk-type reef limestones are known from some parts of the Southern Carpathians in Romania. The Upper Jurassic deposits mainly consist of massif reef limestones including a variety of microbialites associated with micro-encrusters. They played an important role in the formation and evolution of the reef frameworks and thus are of significant importance for deciphering the depositional environments. For our study, the most important encrusting organisms are Crescentiella morronensis, Koskinobullina socialis, Lithocodium aggregatum, Bacinella-type structures, Radiomura cautica, Perturbatacrusta leini, Coscinophragma sp., and crust-forming coralline sponges such as Calcistella. Based on microscopic observations, microbial contribution to reef construction is documented by the abundance of dense micrite, laminate structures, clotted, thrombolithic or peloidal microfabrics, constructive micritic cortices, biogenic encrustations and cement crusts, as well as by other types of microbial structures and crusts. Most of the investigated carbonate deposits can be classified as “coral-microbial-microencruster boundstones” which are characteristic for the Intra-Tethyan domain. Their paleogeographical significance is indicated by the presence of many features comparable with carbonate deposits of rimmed platform systems from the Northern Calcareous Alps or Central Apennines. Based on the distribution of the facies and facies associations within the carbonate sequences under study we can distinguish slope and external shelf margin environments. The microbial crusts, the encrusting micro-organisms, and in some cases the syndepositional cements have stabilized and bound the carbonates of the slope facies types. Subsequently, the stable substrate favored the installation of coral-microbial bioconstruction levels.     

Sequence stratigraphy of an Upper Pennsylvanian,Midcontinent cyclothem from north America (Iola Limestone,Kansas and Missouri,USA)

Summary The Iola Limestone is the open-marine, carbonate portion of a Midcontinent cyclothem. It represents the transgressive and highstand systems tracts of a stratigraphic sequence. The sequence begins with a type 1 sequence boundary at the base of the Chanute Shale, which underlies the Iola. This surface can be recognized by the presence of a paleosol and as much as 15 m of incision. Part of the Chanute is probably an estuarine valley-fill package and represents the lowstand systems tract. The lowest member of the Iola Limestone is the Paola Limestone Member. Its base is sharp and locally has a thin shell lag. This contact is the transgressive surface and represents the onset of open-marine, clear-water carbonate sedimentation. It is a ravinement surface cut by a winnowing environment that appears as a ‘kink’ in the base-level surface. Landward of this ‘kink’, sediment accumulated to a subaerial base-level, but seaward of it sediment did not accumulate above a subtidal threshold probably controlled by wave base. Facies formed during regression also show the influence of a ‘kink’ in base-level. The Paola itself is the lower part of the transgressive facies tract. Overlying the Paola is the Muncie Creck Shale Member; its lower part is black and fissile, contains phosphate nodules, no unequivocally benthic fossils, and no discernible trace fossils. However, this facies is not present everywhere; in much of southeastern Kansas and just north of Kansas City, Missouri, it has been removed by submarine erosion. The only clues that this facies was ever deposited are reworked diagenetic phosphate nodules that occur as a lag on a hardground on top of the Paola. Where black shale and the immediately overlying, relatively unfossiliferous gray shale have been preserved, they are overlain by a shelly lag that incorporates bored and encrusted micritic cobbles-strong evidence of reworking. This erosional surface is interpreted as the maximum flooding surface. Such an interpretation suggests that the black shale formed during sea-level rise and coastal transgression rather than at sea-level highstand. This is further supported by geochemical properties of Midcontinent black shales. Overlying the maximum flooding surface are a thin gray shale (within the Muncie Creek) and the Raytown Lime-stone Member. In southern Kansas, the limestone contains an extensive phylloid-algal mound. In the subsurface, the elongate Raytown mound is perpendicular to the outcrop belt; it directly overlies a Precambrian structural element called the Bourbon arch, suggesting subtle tectonic control. In northern Missouri and in Nebraska, the upper Raytown contains carbonate tidal-flat deposits. The existence of these two facies suggests that the Raytown was deposited while base-level was stable rather than during base-level drop. The aggradational algal mound built into a positive sea-floor feature and did not shift position through the duration of the cycle. Progradational carbonate tidal flats had the chance to develop in the northern part of the field area; if base-level had been dropping, rapid regression would likely not have permitted accumulation of this facies at the top of the limestone. Coarse-grained deposits, an oncolite in southern Kansas and bioclastic packstones and grainstones in northern Kansas, indicate that the mound aggraded up to a subtidal base-level, presumably controlled by wave base. The carbonate tidal flats, on the other hand, filled accommodation space up to a subaerial base-level as they prograded out over this surface. There must have been two base-levels—one subtidal and the other subaerial—connected by the previously mentioned base-level ‘kink’ at the coastline. The Lane Shale, typically gray-green and silty, overlies the Iola. In a core from northern Missouri, the Lane Shale directly overlying the Raytown contains clay slickensides and a breccia of ‘fitted’ carbonate clasts, indicating subaerial exposure and qualifying the base of the Lane Shale as the top boundary of the Iola sequence. In northwestern Missouri, the Iola changes from a relatively clay-free limestone to mostly dark-gray, calcareous mudrocks with thin shell stringers. This represents a part of the basin dominated by clastic input. Stratigraphic interpretation implies that the Muncie Creek black shale formed during accommodation space increase and shoreline transgression. This is consistent with recent geochemical studies of Midcontinent black shales. This lithology formed as inland peat swamps underwent ravinement and organic matter was flushed onto the shelf. An influx of nutrients and plant material made available by sea-level rise and transgression while sediment was trapped in nearshore accommodation space was the primary cause of sediment starvation and anoxia in the basin.     

From ramp to platform: building a 3D model of depositional geometries and facies architectures in transitional carbonates in the Miocene, northern Sardinia

The depositional geometry and facies distribution of an Early Miocene (Burdigalian) carbonate system in the Perfugas Basin (NW Sardinia) comprise a well-exposed example of a transition from a ramp to a steep-flanked platform. The carbonate succession (Sedini Limestone Unit) is composed of two depositional sequences separated by a major erosional unconformity. The lower (sequence 1) records a ramp dominated by heterozoan producers and the upper (sequence 2) is dominated by photozoan producers and displays a gradual steepening of the depositional profile into a steep-flanked platform. This paper shows the process of creating a digital outcrop model including a facies model. This process consists of combining field data sets, including 17 sedimentary logs, and a spatial dataset consisting of differential global positioning system data points measured along key stratigraphic surfaces and sedimentary logs, with the goal of locking traditional field observations into a 3D spatial model. Establishing a precise geometrical framework and visualizing the overall change in the platform geometry and the related vertical and lateral facies variations of the Sedini carbonate platform, allows us to better understand the sedimentary processes leading to the geometrical turn-over of the platform. Furthermore, a detailed facies modeling helps us to gain insight into the detailed depositional dynamics. The final model reproduces faithfully the depositional geometries observed in the outcrops and helps in understanding the relationships between facies and architectural framework at the basin scale. Moreover, it provides the basis to characterize semiquantitatively regional sedimentological features and to make further reservoir and subsurface analogue studies.     

Facies evolution and sequence chronostratigraphy of a “mid”-Cretaceous shallow-water carbonate succession of the Apulia Carbonate Platform from the northern Murge area (Apulia,southern Italy)

The “mid”-Cretaceous carbonate succession of the Apulia Carbonate Platform cropping out in northern Murge area (Apulia, southern Italy) is composed of shallow-water carbonate rocks and is over 400 m in thickness. This paper focuses on the lithofacies analysis of this carbonate succession, its paleoenvironmental interpretation, and its sequence-chronostratigraphic architecture. Lithofacies analysis permitted to identify deposits which can be grouped into the following three facies belts: (1) terrestrial facies belt formed by: intraclast-supported paleosoils; solution-collapse breccias; (2) restricted facies belt made up of lithofacies deposited in protected peritidal environments; (3) normal-marine facies belt made up of lithofacies formed in moderate- to high-energy subtidal environments. The detailed study both in outcrops and in thin-sections revealed that, at the bed scale, lithofacies are cyclically arranged and form shallowing-upward small-scale depositional sequences comparable to parasequences and/or simple sequences. The following three small-scale sequence types have been distinguished: (1) subtidal sequences mostly made up of lithofacies formed in the normal-marine open subtidal domain; (2) peritidal sequences made up of lithofacies formed in the restricted peritidal domain; (3) peritidal sequences showing a cap formed by paleosoils. Small-scale sequences are not randomly arranged in the compiled succession but form discrete packages, or sets, that alternate in the sedimentary record. The repetition of such small-scale sequence packages in the succession has been the key to recognize large-scale sequences comparable to third-order depositional sequences. Although sedimentological data are often fragmentary due to late dolomitization, four large-scale sequences have been distinguished. The data support a generalized landward-backstepping of facies belts during transgression, which implies a gradual gain of accommodation culminating with the deposition of a package of small-scale sequences formed by normal-marine subtidal deposits. These mark periods of maximum accommodation space and form the maximum-flooding zones of large-scale sequences. A gradual seaward progradation of facies belts is recorded during highstand conditions, which implies a gradual loss of accommodation culminating with the deposition of a package of peritidal small-scale sequences capped by paleosoils or by solution-collapse breccias. The occurrence of terrestrial deposits marks periods of minimum accommodation on the platform and determines the sequence boundary of large-scale sequences. The large-scale sequences identified in this study fit with the main transgressive/regressive cycles published in the sequence-chronostratigraphic chart of European basins. As a consequence, it is interpreted that changes of the sea level recorded at the scale of European basins played an important role in determining the sequence-stratigraphic architecture of the studied succession. In spite of this, the occurrence of solution-collapse breccias, which implies a significant gap in carbonate sedimentation in between Early and Middle Cenomanian times, may also have an alternative interpretation. In particular, this deposit may represent the local fingerprint of the well-known tectonic phase which, during Late Albian-Early/Middle Cenomanian times, determined the subaerial exposure of large parts of Periadriatic carbonate platforms producing a marked regional unconformity.     

Upper miocene carbonate ramp deposits from the southernmost part of Maiella Nountain (Abruzzo, Central Italy)

Summary The development of carbonate ramp depositional systems in the Neogene of the Mediterranean Region represents a widespread feature so far analysed in several papers. It is striking to note that the evolution of upper Miocene carbonate ramps, characterized by the presence of coralgal bioherms, highlights the events leading to the Messinian salinity crisis. The coralgal bioherms of preevaporite Messinian age exhibit fossil assemblages indicating marine waters with normal salinity, whereas stromatolitic and microbial encrustations underline the deterioration of the environment during the Messinian salinity crisis. Maiella Mountain is a broad carbonate massif located in Abruzzo (Central Italy). The late lower Oligocene-Messinian part of its stratigraphic succession consists of stacked non-tropical carbonate ramp deposits related to third and higher order sequences. The investigations performed in the southernmost portion of the massif allowed to recognize a complete fourth order carbonate depositional sequence on a homoclinal ramp of pre-evaporite Messinian age. The presence of small coralgal patch reefs and overlaying microbial encrustations is significant. A transect exhibits the stratigraphic framework of the area. The data show how local parameters play a notable role in the development of these deposits.     

The Recurrence of Parathuramminacea and Archaesphaeracea Representatives at the Tournaisian–Viséan Boundary of the Lower Carboniferous (the Kipchak Section,the Eastern Slope of the Southern Urals)

Paleontological Journal - The Tournaisian–Viséan boundary of the Lower Carboniferous was established in carbonate facies deposits of the “Kipchak” section (Southern Urals)....     

Characteristics of the Lofer cyclicity in the type locality of the Dachstein Limestone (Dachstein Plateau,Austria)

In the present paper, the results of our studies in the type locality of the Dachstein Limestone are summarised in order to contribute to the correct interpretation of the Lofer cycles. In the sections studied on the Dachstein Plateau, the boundaries of the Lofer cycles are usually erosional disconformities showing karstification features. Penetration by karstic solution was not more than a few decimetres, since during the recurrent sea-level drops the platform only slightly emerged above sea level. The reddish or greenish argillaceous carbonate interlayers (facies A) cannot be interpreted as in situ palaeosol horizons. They are tidal flat deposits consisting predominantly of subtidal carbonate mud redeposited by storms that was mixed with reworked airborne fine carbonate particles and argillite and/or reworked lateritic soil, which were accumulated on the subaerially exposed platform. Rip-ups from consolidated sediment, blackened intraclasts and skeletons of tidal flat biota may have also contributed to the sediment of facies A. Erosional boundaries of most of the investigated cycles, and definite features of karstic solution beneath the disconformities, suggest periodical drops of sea level followed by a renewed transgression. This appears to confirm the allocyclic model for the explanation of the origin of the Lofer cycles.     

The tangled cases of Deinogalerix (Late Miocene endemic erinaceid of Gargano) and Galericini (Eulipotyphla,Erinaceidae): a cladistic perspective

The Late Miocene giant erinaceid Deinogalerix from Scontrone and Gargano (Italy) is associated with many other vertebrates in deposits of a past island, the “Abruzzo‐Apulia Platform”. At Gargano, Deinogalerix is accompanied by the moderately endemized Galericini Apulogalerix. This first extensive cladistic analysis is aimed at defining the relationships of Deinogalerix with characteristic members of the tribe Galericini. The analysis was performed on a matrix of 30 characters and 19 taxa and identified some smaller clades, nested within three major ones. The latter include: (i) a pentatomy of Galerix species, (ii) a polytomy of “transitional” Galerix–Parasorex species and (iii) a large clade with Parasorex, Schizogalerix and Gargano representatives. Galerix and Parasorex proved to be paraphyletic and Schizogalerix monophyletic. Based on the results of the analysis, Deinogalerix and Apulogalerix have distinct origins, which supports an asynchronous colonization of the island. The line of Deinogalerix possibly stemmed from some eastern species transitional between Galerix and Parasorex around Mammal Neogene (MN) zone 2. Conversely, the line of Apulogalerix originated from a primitive Parasorex ibericus, or a close relative, around MN 9–10. Another important result was detecting an impressive early Miocene (MN 2?) radiation of Galericini. Moreover, Schizogalerix and Parasorex originated from eastern Galericini morphologically transitional between Galerix and Parasorex.     

Lithostratigraphy and carbonate microfacies across the Permian–Triassic boundary near Julfa (NW Iran) and in the Baghuk Mountains (Central Iran)

Permian–Triassic boundary sections in the Julfa (NW Iran) and Abadeh (Central Iran) regions display a succession of three characteristic rock units, (1) the Paratirolites Limestone with the mass extinction horizon at its top, (2) the ‘Boundary Clay’, and (3) the earliest Triassic Elikah Formation with the conodont P–Tr boundary at its base. The carbonate microfacies reveals a facies change, in the sections near Julfa, within the Paratirolites Limestone with an increasing number of intraclasts, Fe–Mn crusts, and biogenic encrustation. A decline in carbonate accumulation occurs towards the top of the unit with a sponge packstone in the sections, and finally resulting in a complete demise of the carbonate factory. The succession of the ‘Boundary Clay’ differs in the two regions; thin horizons of sponge packstone are present in the Julfa region and ‘calcite fans’ of probably inorganic origin in the Abadeh Region. The skeletal carbonate factory of the Late Permian was restored with the deposition of microbial carbonates at the base of the Elikah Formation, where densely laminated bindstone, floatstone with sparry calcite spheres, and oncoid wackestone/floatstone predominate.     

Sedimentology and depositional sequences of a Kimmeridgian carbonate ramp system,Lower Saxony Basin,Northern Germany

Shallow-marine Kimmeridgian (Late Jurassic) deposits in the Lower Saxony Basin (LSB) composed of alternating limestone, marl and claystone attract great palaeontological interest due to their rich invertebrate and vertebrate assemblages. Unfortunately, the absence of open-marine marker fossils and numerous sedimentary gaps in combination with lateral facies changes hamper the precise stratigraphic correlation of these strata on both a local and global scale. Here, an integrated approach combining carbonate microfacies analysis, ostracod biostratigraphy and high-resolution sequence stratigraphy is applied to two Kimmeridgian sections (Langenberg and Bisperode, 60 km apart) in the southeastern LSB. High-resolution carbonate microfacies analysis enables the definition of 19 microfacies types and seven microfacies associations, which can be arranged into facies belts along a carbonate ramp. Vertical microfacies, bed thickness and diagnostic surfaces define stacking patterns that are interpreted as small-, medium- and large-scale sequences. The ostracod biostratigraphic framework established in this study provides the required stratigraphic control. Correlation of the two studied sections reveals a more proximal setting for Bisperode than Langenberg and an overall shallowing-up trend from mid-ramp to proximal inner ramp developed in both sections. Furthermore, the majority of the medium-scale sequence boundaries defined in this study can be found in similar biostratigraphic positions in other European basins. Synsedimentary tectonics combined with high sediment accumulation rates can be identified as important controlling factors for the distribution and composition of the Kimmeridgian deposits in the LSB based on detailed correlation on both a regional and super-regional scale.     

柴达木盆地晚中新世三趾马化石

Bohlin描述的柴达木动物群中的三趾马材料非常少 ,仅能证明三趾马在这个地点的存在。近年来新的野外考察在这一地区发现了更多的三趾马化石材料 ,至少包括 3个种 ,即Hipparioncf.H .chiai、H .weihoense和H .teilhardi。H .cf.H .chiai和H .weihoense在柴达木盆地的发现进一步证实了晚中新世早期 (保德早期 )动物群在这个地区的存在。柴达木盆地的H .teilhardi基本上与H .cf.H .chiai和H .weihoense产自同一层位 ,其时代也应为保德早期。H .cf.H .chiai和H .weihoense在柴达木盆地的发现为该地区在晚中新世早期为草原型环境的判断提供了更多的证据。H .teilhardi更细长的远端肢骨也是对开阔环境的一种适应性状     

Stromatolite biostromes and associated facies in the late precambrian porsanger dolomite formation of Finnmark,Arctic Norway

The Late Precambrian Porsanger Dolomite Formation, occurring beneath the Varanger tillite in Arctic Norway, consists of various dolomitic lithofacies of subtidal, intertidal and supratidal environments. The lithofacies belong to three facies associations, A, B and C, which are repeated several times in the sequence. Facies association A comprises cryptalgal laminites, dolomicrites and thin-bedded grainstones and flakestones. The environment represented by this facies is broadly intertidal (locally supratidal) flat, with the interbedded carbonate sands representing storm deposits. Facies association B, of shallow subtidal to low intertidal origin, comprises cross-bedded carbonate sands (flakestones, grainstones and oolites) forming units up to 10 m thick. Small stromatolite bioherms (5 m wide, 2 m high) are locally developed within these “high-energy” deposits. Facies association C formed in a subtidal environment consists of laterally extensive (over 20 km) uniformly developed stromatolite biostromes, up to 16 m thick. The biostromes, locally divided by channels filled with grainstones and intraformational conglomerates, are composed of cylindrical and turbinate columnar (SH-V and SH-C) and digitate stromatolites (Gymnosolen, Inseria and Tungussia) in their lower parts. Larger, bulbous (SH-C and LLH-C) and conical (Conophyton) stromatolites occur in the upper parts, as well as the branching conophyte, Jacutophyton.All of the biostromes are always developed above cross-bedded carbonate sands (facies association B). A broadly symmetrical cyclic pattern, A B C B A, of tidal flat deposits (facies association A) passing up into carbonate sands (B), into biostrome (C), overlain by carbonate sands (B) and then tidal flat deposits (A), is repeated four times in the Porsanger Dolomite sequence. The pattern is interpreted in terms of two controls on sedimentation: (1) a slow transgressive phase followed by (2) depositional regression. The former (1) took place either through eustatic sea-level rise or more likely through accelerated subsidence because of tectonic instability and compaction of underlying sediments. This resulted in the sequence: tidal flat sediments, low intertidal/shallow subtidal carbonate sands, subtidal biostrome (A, B, C). Depositional regression through prograding tidal flats, generated the shoaling upward part of the cycle: biostrome, carbonate sands, tidal flat sediments (C, B, A).