27 results on '"*NEOGENE paleoecology"'
Search Results
2. NEOGENE PARATETHYAN CROAKERS (TELEOSTEI, SCIAENIDAE).
- Author
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BANNIKOV, ALEXANDRE F., SCHWARZHANS, WERNER, and CARNEVALE, GIORGIO
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FOSSIL sciaenidae ,NEOGENE paleoecology ,ARGYROSOMUS ,ATRACTOSCION ,SEA basses ,SKELETON - Abstract
The fossil record of sciaenid fishes (based on both otoliths and osteological finds) from the Neogene of the Paratethys is reviewed. The species Labrax (=Morone) multipinnatus Gorjanović-Kramberger, 1882 from the Sarmatian of Croatia (Sv. Nedelja) that was originally described as a sea bass of the family Moronidae is re-assigned to the extant croaker genus Argyrosomus. Two new genera and species of sciaenid fishes are described based on a single skeleton each, namely Landinisciaena popovi gen. et sp. nov. from the Tarkhanian (Lower/Middle Miocene) North Shirvanskaya Formation exposed along the Pshekha River, North Caucasus, Russia, and Croatosciaena krambergeri gen. et sp. nov. from the Sarmatian s.s. (Middle Miocene) deposits of Dolje in the nearby of the city of Zagreb, Croatia. The holotype of the former taxon possesses a well-preserved saccular otolith in situ (first record of in situ croaker otolith in Europe) similar to the otoliths of the extant genus Atractoscion. The otolith-based Ottnangian species Atractoscion elongatissimus Schwarzhans, 1993 is transferred to the genus Landinisciaena gen. nov. A comprehensive revision of the Neogene otholith-based sciaenid record from Paratethys resulted in the recognition of three new genera (Chaoia gen. nov., Pontosciaena gen. nov. and Leptosciaena gen. nov.) as well as in the description of a new species L. caputoi sp. nov. from the uppermost Messinian (Lago-mare phase) of Italy. A number of known otholith-based species were either synonymized or assigned to a new generic affiliation. The complex biogeographic history of the Neogene Paratethyan sciaenids (based on both otoliths and skeletal records) is discussed, resulting in the recognition of a vanished “sciaenid bioprovince". [ABSTRACT FROM AUTHOR]
- Published
- 2018
3. Neogene-Quaternary Magmatism of the Çaldıran Plain and its Vicinity (Eastern Turkey): an Example of Post-Collisional Transition from Subduction to Intraplate Type.
- Author
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Lebedev, V. A., Parfenov, A. V., and Yakushev, A. I.
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SUBDUCTION zones ,PLIOCENE-Pleistocene boundary ,VOLCANIC activity prediction ,NEOGENE paleoecology ,VOLCANISM - Abstract
This paper is aimed at studying the chronological evolution of the Neogene-Quaternary volcanic activity within the Çaldıran plain and its mountainous framing (Eastern Turkey). It is shown that the last pulse of continental-margin magmatism related to the subduction and closure of Neotethys oceanic basin occurred in the Middle Miocene (13.5-12.5 Ma). The post-collision volcanism proceeding simultaneously with large-scale regional tectonic rearrangement and initiation of the long-term Çaldıran fault began in the Late Miocene (7-6 Ma), and reached maximum activity in the Middle Pliocene (4.7-3.6 Ma). The Quaternary period in the region evolution was marked by the abundant within-plate magmatic activity restricted to the regional SW-NE trending zone, and the formation of Eastern Turkey’s largest Tendürek shield volcano (Late Pleistocene-Holocene). Petrological-geochemical data indicate that magmas during the overall evolution of young volcanism of the Çaldıran plain was generated from a single mantle reservoir, whose composition gently one-way evolved with time. Calculations show that melting occurred in the upper part of the asthenosphere (immediately near the boundary with thinned lithospheric mantle), which was metasomatized by pre-existing long-continued subduction. The chemical variations of mantle source with time (from the Middle Miocene to Quaternary) were mainly determined by a decrease of subduction component and the presence of aqueous phases, with a general trend from E-MORB to OIB-type for generated magmas. The composition of Late Quaternary basic lavas of Tendürek Volcano in terms of most petrological-geochemical characteristics corresponds to within-plate alkaline basalts. The main trend of geochemical evolution of mantle source is correlated with a systematic change of the predominant serial affinity of igneous rocks from calcalkaline through moderately alkaline to Na-alkaline varieties. Discrete character of young magmatism within the Çaldıran plain, and its subsequent evolution (sulrasubduction → post-collision → within-plate) were mainly determined by periodical large-scale changes in geotectonic setting within the Eurasian-Arabian collision zone: (1) cessation of subduction, (2) break-up and deepening of oceanic slab with its subsequent break off, (3) inferred emergence of incipient rift setting under conditions of intense submeridional compression. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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4. Neogene Caribbean elasmobranchs: Diversity, paleoecology and paleoenvironmental significance of the Cocinetas Basin assemblage (Guajira Peninsula, Colombia).
- Author
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Carrillo-Briceño, Jorge Domingo, Luz, Zoneibe, Hendy, Austin, Kocsis, László, Aguilera, Orangel, and Vennemann, Torsten
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CHONDRICHTHYES ,NEOGENE paleoecology ,PALEOENVIRONMENTAL studies ,ECOLOGICAL succession ,ESTUARINE ecology - Abstract
The Cocinetas Basin is located on the eastern flank of La Guajira Peninsula, northern Colombia (South Caribbean). During late Oligocene through Pliocene, much of the basin was submerged. The extensive deposits in this area suggest a transition from a shallow marine to a fluvio-deltaic system, with a rich record of invertebrate and vertebrate fauna. The elasmobranch assemblages of the early Miocene to late Pliocene succession in the Cocinetas Basin (Jimol, Castilletes and Ware Formations, and Patsúa Valley) are described for the first time. The assemblages include at least 30 taxa of sharks (Squaliformes, Pristiophoriformes, Orectolobiformes, Lamniformes and Carcharhiniformes) and batoids (Rhinopristiformes and Myliobatiformes), of which 24 taxa are reported from the Colombian Neogene for the first time. Paleoecological and paleoenvironmental interpretations are based on the feeding ecology, and on estimates of paleosalinity using stable isotope compositions of oxygen in the bioapatite of shark teeth. The isotopic composition of studied specimens corroborates the paleoenvironmental settings for the studied units suggested on the basis of other proxies. These Neogene elasmobranch assemblages from the Cocinetas Basin, provide new insights of the shark and ray diversity inhabiting the coastal and estuarine environments of the northwestern margin of South America, both during the existence of the gateway between the Atlantic and Pacific Oceans, and following its closure. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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5. The effects of the inception of Amazonian transcontinental drainage during the Neogene on the landscape and vegetation of the Solimões Basin, Brazil.
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Leite, Fatima P.R., Paz, Jackson, do Carmo, Dermeval A., and Silva-Caminha, Silane A.
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NEOGENE paleoecology ,BIOGEOGRAPHY ,PALEOGEOGRAPHY ,BIOSTRATIGRAPHY ,VEGETATION patterns ,DRAINAGE ,LANDSCAPES ,PLIOCENE paleoecology - Abstract
Amazonia covers nearly 50% of Brazil. The history of this biome is marked by many changes in the landscape caused mainly by the Central and Northern Andes uplift. This event has influenced the palaeogeography of the Amazon and therefore its biogeography and possibly biodiversity. Herein we present palynological and lithostratigraphical results from the Solimões Formation in the well 1AS-33-AM. It was drilled in the Solimões Basin, Amazonas State, Brazil, reaching 405 m in depth. We identified 152 palynomorphs, in 32 samples, among them some biostratigraphical markers, such asCrassoretitriletes vanraadshoovenii,Fenestrites spinosus,Cichoreacidites longispinosus,Ladakhipollenites?caribbiensisandEchitricolporites mcneillyi, allowing us to recognise four biozonessensuLorente (1986):CrassoretitriletesInterval Zone (399.10–276.70 m), Asteraceae Interval Zone (276.70–262.00 m),Psilatricolporites caribbiensisInterval Subzone (239.90–70.00 m) andEchitricolporites–AlnipollenitesInterval Subzone (70–32 m). The palynological and lithostratigraphical results indicate two environmental phases. The palynomorph association presents a change marked by the sudden appearance and predominance ofGrimsdalea magnaclavatafrom 239.90 m upwards and a general increase in the number of species. The lithostratigraphy shows from approximately the same depth greater amounts of sandstones towards the top of the well, suggesting a change from a paralic to a fluvial environment of higher energy. The first phase can be associated with the Pebas/Acre depositional systems, wetlands composed by lakes and swamps with seasonal floods that existed from 23 to 7–5 Ma. The second phase indicates a fluvial system that may be interpreted as a record of the modern Amazon transcontinental fluvial system, which was already established in the Pliocene. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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6. Disentangling the influence of climatic and geological changes on species radiations.
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Linder, H. Peter, Rabosky, Daniel L., Antonelli, Alexandre, Wüest, Rafael O., Ohlemüller, Ralf, and Carine, Mark
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NEOGENE paleoceanography ,NEOGENE paleoecology ,CLIMATE change ,NEOGENE paleoclimatology ,NEOGENE paleoseismology - Abstract
Aim Our aim was to seek explanations for the differences in the diversity among the austral continents by comparing the diversification rates and patterns in the grass subfamily Danthonioideae. We asked specifically whether diversification is density dependent, whether it is different for each continent, and whether immigration rates impact on diversification rates. We attempted to account for intercontinental differences by comparing the Pleistocene climatic and Neogene geomorphological histories with the inferred diversification rates. Location Mainly the Southern Hemisphere, treated as four areas for the analyses: Africa, Australia, New Zealand and South America. Methods We based our analyses on a densely sampled, dated phylogeny for the grass subfamily Danthonioideae. We compared 24 diversification models for these continental radiations, taking into account speciation models, and extinction and dispersal rates. We used available distribution data to infer the climates under which danthonioids are found, and used these to estimate the change in area and location of suitable habitats between contemporary and Last Glacial Maximum climates. We inferred the geomorphological history from the literature. Results We show that long-distance dispersal led to parallel radiations, which more than doubled the final standing diversity in the subfamily. Diversification models with the strongest support included separate time-varying diversification processes for each major geographical region. Pleistocene climatic fluctuation did not explain the intercontinental differences in diversification patterns. Main conclusions Although our results are consistent with density-dependent diversification, this explanation is not consistent with the time of arrival of danthonioids on each continent. The diversification patterns on the four major Southern Hemisphere landmasses are idiosyncratic. The two most important predictors of diversity may be the lineage-specific effect of time, and the general effect of topographical complexity and orogenesis. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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7. A Reevaluation of the Morphology, Paleoecology, and Phylogenetic Relationships of the Enigmatic Walrus Pelagiarctos.
- Author
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Boessenecker, Robert W. and Churchill, Morgan
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WALRUS ,FOSSIL marine animals ,ODOBENIDAE ,NEOGENE paleoceanography ,NEOGENE paleoecology - Abstract
Background: A number of aberrant walruses (Odobenidae) have been described from the Neogene of the North Pacific, including specialized suction-feeding and generalist fish-eating taxa. At least one of these fossil walruses has been hypothesized to have been a specialized predator of other marine mammals, the middle Miocene walrus Pelagiarctos thomasi from the Sharktooth Hill Bonebed of California (16.1-14.5 Ma). Methodology/Principal Findings: A new specimen of Pelagiarctos from the middle Miocene "Topanga" Formation of southern California (17.5-15 Ma) allows a reassessment of the morphology and feeding ecology of this extinct walrus. The mandibles of this new specimen are robust with large canines, bulbous premolars with prominent paraconid, metaconid, hypoconid cusps, crenulated lingual cingula with small talonid basins, M
2 present, double-rooted P3 -M1 , single-rooted P1 and M2 , and a P2 with a bilobate root. Because this specimen lacks a fused mandibular symphysis like Pelagiarctos thomasi, it is instead referred to Pelagiarctos sp. This specimen is more informative than the fragmentary holotype of Pelagiarctos thomasi, permitting Pelagiarctos to be included within a phylogenetic analysis for the first time. Analysis of a matrix composed of 90 cranial, dental, mandibular and postcranial characters indicates that Pelagiarctos is an early diverging walrus and sister to the late Miocene walrus Imagotaria downsi. We reevaluate the evidence for a macropredatory lifestyle for Pelagiarctos, and we find no evidence of specialization towards a macrophagous diet, suggesting that Pelagiarctos was a generalist feeder with the ability to feed on large prey. Conclusions/Significance: This new specimen of Pelagiarctos adds to the knowledge of this problematic taxon. The phylogenetic analysis conclusively demonstrates that Pelagiarctos is an early diverging walrus. Pelagiarctos does not show morphological specializations associated with macrophagy, and was likely a generalist predator, feeding on fish, invertebrates, and the occasional warm-blooded prey item. [ABSTRACT FROM AUTHOR]- Published
- 2013
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8. Cryptic Diversity of African Tigerfish (Genus Hydrocynus) Reveals Palaeogeographic Signatures of Linked Neogene Geotectonic Events.
- Author
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Goodier, Sarah A. M., Cotterill, Fenton P. D., O'Ryan, Colleen, Skelton, Paul H., and de Wit, Maarten J.
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HYDROCYNUS ,CHARACIDAE ,MITOCHONDRIAL DNA ,CYTOCHROME b ,NEOGENE paleoecology - Abstract
The geobiotic history of landscapes can exhibit controls by tectonics over biotic evolution. This causal relationship positions ecologically specialized species as biotic indicators to decipher details of landscape evolution. Phylogeographic statistics that reconstruct spatio-temporal details of evolutionary histories of aquatic species, including fishes, can reveal key events of drainage evolution, notably where geochronological resolution is insufficient. Where geochronological resolution is insufficient, phylogeographic statistics that reconstruct spatio-temporal details of evolutionary histories of aquatic species, notably fishes, can reveal key events of drainage evolution. This study evaluates paleo-environmental causes of mitochondrial DNA (mtDNA) based phylogeographic records of tigerfishes, genus Hydrocynus, in order to reconstruct their evolutionary history in relation to landscape evolution across Africa. Strong geographical structuring in a cytochrome b (cyt-b) gene phylogeny confirms the established morphological diversity of Hydrocynus and reveals the existence of five previously unknown lineages, with Hydrocynus tanzaniae sister to a clade comprising three previously unknown lineages (Groups B, C and D) and H. vittatus. The dated phylogeny constrains the principal cladogenic events that have structured Hydrocynus diversity from the late Miocene to the Plio-Pleistocene (ca. 0-16 Ma). Phylogeographic tests reveal that the diversity and distribution of Hydrocynus reflects a complex history of vicariance and dispersals, whereby range expansions in particular species testify to changes to drainage basins. Principal divergence events in Hydrocynus have interfaced closely with evolving drainage systems across tropical Africa. Tigerfish evolution is attributed to dominant control by pulses of geotectonism across the African plate. Phylogenetic relationships and divergence estimates among the ten mtDNA lineages illustrates where and when local tectonic events modified Africa's Neogene drainage. Haplotypes shared amongst extant Hydrocynus populations across northern Africa testify to recent dispersals that were facilitated by late Neogene connections across the Nilo-Sahelian drainage. These events in tigerfish evolution concur broadly with available geological evidence and reveal prominent control by the African Rift System, evident in the formative events archived in phylogeographic records of tigerfish. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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9. Gratkorn: A benchmark locality for the continental Sarmatian s.str. of the Central Paratethys.
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Gross, M., Böhme, M., and Prieto, J.
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MIOCENE paleoecology ,VERTEBRATES ,NEOGENE paleoecology ,NEOGENE paleoclimatology ,DROUGHTS - Abstract
This paper presents one of the richest and most complete vertebrate faunas of the late Middle Miocene (~12 Ma) of Central Europe. Up to now, sixty-two vertebrate taxa, comprising all major groups (fishes, amphibians, reptiles, birds, mammals), have been recorded. Based on sedimentological and palaeobiological evidences, this Fossillagerstätte is assumed to originate from a floodplain paleosol formed on top of a braided river sequence. The fauna points to a highly structured, somewhat vegetated landscape with a wide array of habitats (e.g., fluvial channels, sporadically moist floodplains, short-lived ponds, savannah-like open areas and screes). It was preserved due to a rapid drowning and the switch to a freshwater lake environment. Palaeoclimatological data, derived from pedogenic features as well as from biota, indicate an overall semi-arid, subtropical climate with distinct seasonality (mean annual precipitation 486 ± 252 mm, mean annual temperature ~15°C). This underlines the late Middle/early Late Miocene dry-spell in Central Europe. From taphonomical point of view, the irregularly distributed but roughly associated larger vertebrate remains refer to an in situ accumulation of the bone bed. Splintered bones, gnawing marks as well as rhizoconcretions and root corrosion structures record some pre- and post-burial modification of the taphocoenose. However, the findings of pellet remains argue for a very fast burial and thus to a low degree of time-averaging. For this reason, the fossil fauna reflects the original vertebrate community rather well and is a cornerstone for the understanding of late Middle Miocene terrestrial ecosystems in this region. Certainly, Gratkorn will be one of the key faunas for a high-resolution continental biostratigraphy and the comprehension of Europe's faunal interchanges near the Middle/Late Miocene transition. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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10. A New Extinct Genus of Cavioidea (Rodentia, Hystricognathi) from the Miocene of Patagonia (Argentina) and the Evolution of Cavioid Mandibular Morphology.
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Pérez, María and Vucetich, María
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CAVIIDAE ,HYDROCHAERIDAE ,FOSSILS ,PHYLOGENY ,NEOGENE paleoecology - Abstract
The family Caviidae is represented in modern faunas by cavies and maras, whereas the family Hydrochoeridae is represented by capybaras. The evolutionary origin of these families has been related to a diversity of plesiomorphic fossil forms (recorded from the late Oligocene up to the middle Miocene) traditionally grouped in the family 'Eocardiidae'. These fossil forms were included, together with Caviidae and Hydrochoeridae, within the Cavioidea s.s. (sensu stricto), because they share high crowned cheek teeth, double-hearted occlusal surface, short lower incisors, and moderate hystricognathy. Within Cavioidea s.s., caviids and hydrochoerids were interpreted as forming its crown group, because they have unique craniomandibular and dental features. In this contribution, a new taxon of Cavioidea s.s. from the middle Miocene of central Patagonia, Argentina, is described, and its phylogenetic position is determined on the basis of a morphological cladistic analysis in which 'eocardiids' were included. The study permits the understanding of the sequence of appearance of characters that originated the highly divergent morphology of crown-group cavioids. The analysis of the sequence of appearance of the characters that traditionally diagnosed the crown group indicates that these changes did not occur at the same time. On the contrary, many of these features seem to have appeared at different nodes of the evolutionary history of Cavioidea s.s. The remarkably derived morphology of modern cavioids is the result of a stepwise appearance of a mosaic of evolutionary innovations that originated gradually along the history of Cavioidea during the late-middle Miocene. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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11. Evolving between land and water: key questions on the emergence and history of the Hippopotamidae (Hippopotamoidea, Cetancodonta, Cetartiodactyla).
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Boisserie, Jean-Renaud, Fisher, Rebecca E., Lihoreau, Fabrice, and Weston, Eleanor M.
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FOSSIL hippopotamidae ,PHYLOGENY ,BIOGEOGRAPHY ,ARTIODACTYLA ,BIOLOGICAL evolution ,CLIMATE change ,NEOGENE paleoecology - Published
- 2011
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12. Palaeoecology of Late Pliocene and Quaternary mammalian communities in the Carpathian Basin.
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Pazonyi, Piroska
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NEOGENE paleoecology ,NEOGENE Period ,MAMMALS ,ECOLOGY ,BIOCLIMATOLOGY - Abstract
Late Neogene and Quaternary changes of climate and vegetation in the Carpathian Basin can be reconstructed using some ecological parameters of mammalian communities. This study is based on mammalian faunal data from 156 layers of 64 Upper Pliocene, Pleistocene and Holocene localities from the Carpathian Basin. Some of the applied methods analyse the species composition of mammalian faunas (cluster analysis, similarity and longevity studies, and reconstruction of evolutionary lineages). These methods allow the documentation of the first-, second- and third-order events in the mammalian fauna. The other group of analyses consists of taxon-free methods which are based on the ecological parameters (body size, trophic preferences, number of species) of mammalian species and communities. The distribution of ecotypes in a fauna (ecological variables) is primarily determined by the climate and vegetation. Therefore the ecological variables (distribution of body size and the trophic preferences, diversity index) together define the ecological unit which is characteristic to the community. In the Carpathian Basin 10 ecological units are distinguished and interpreted in the studied period. The succession of these ecological units provides a useful framework for tracking Late Pliocene and Quaternary changes in climate and vegetation. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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13. Characteristic analysis of large-scale loess landslides: a case study in Baoji City of Loess Plateau of Northwest China.
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Wang, H. B., Zhou, B., Wu, S. R., Shi, J. S., Li, B., Glade, T., and Bai, S.
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LANDSLIDES ,LOESS ,SEEPAGE ,NEOGENE paleoecology ,MATERIALS analysis - Abstract
Landslides are one of the most common geologic hazards in the Loess Plateau of northwest China, especially with some of the highest landslide densities found in Shaanxi and adjacent provinces. Prior to assessing the landslide hazard, a detailed landslide inventory map is fundamental. This study documents the landslides on the northwest Loess Plateau with high accuracy using high-resolution Quickbird imagery for landslide inventory mapping in the Changshou valley of Baoji city. By far the majority of landslides are in loess, representing small-scale planar sliding. Most of the large-scale landslides involve loess and bedrock, and the failure planes occurred either along the contacts between fluvial deposits and Neogene argillites, or partially within the bedrock. In the sliding zones of a large scale landslide, linear striations and fractures of the soils were clearly developed, clay minerals were oriented in the same direction and microorganism growths were present. From the analysis of microstructure of sliding soils, it is concluded that the Zhuyuan landslide can be reactivated if either new or recurring water seepage is caused in the sliding surface. It can be concluded that most landslides are attributed to the undercutting of the slope associated with gullying, and numerous ancillary factors including bedrock-loess interface, slope steepness, vegetation cover and land utilization. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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14. Functional morphological analysis of evolution of ribbing in pliocene viviparid shells from Croatia H. Posilović & Z. Bajraktarević Pliocene viviparid shell evolution.
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POSILOVIĆ, HRVOJE and BAJRAKTAREVIĆ, ZLATAN
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MORPHOLOGY ,GASTROPOD culture ,PHYLOGENY ,NEOGENE paleoecology - Abstract
Posilović, H., & Bajraktarević, Z. 2010: Functional morphological analysis of evolution of ribbing in pliocene viviparid shells from Croatia. Lethaia, 10.1111/j.1502-3931.2009.00209.x. This paper provides a functional analysis of Pliocene freshwater gastropods from the phylogenetic lineage of Viviparus neumayri to Viviparus ornatus. On this section of the phylogenetic line, it is possible to follow the continuous evolution of the shell ornamentation (shouldering and rib formation) from ancestral V. neumayri with smooth shell to V. ornatus with spiral ribs. The shell morphology and possible structural function of rib development is discussed from the analytical point of view, but also by Finite Element Modelling. Spiral rib development in the viviparids is not correlated with shell thickening, but rather with strengthening of the shell is achieved through development of spiral ribs, with direct biomechanical and evoloutionary significance. □ Croatia, functional morphology, gastropod shell evolution, Pliocene, viviparid evolution. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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15. NEOGENE LEAF MORPHOTAXA OF MALVACEAE S.L. IN EUROPE.
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NEOGENE paleoecology ,MALVACEAE ,FOSSIL leaves ,PLANT morphology ,EPIDERMAL growth factor - Published
- 2010
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16. DIVERSIFICATION AND PERSISTENCE AT THE ARID–MONSOONAL INTERFACE: AUSTRALIA-WIDE BIOGEOGRAPHY OF THE BYNOE'S GECKO ( HETERONOTIA BINOEI; GEKKONIDAE).
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Fujita, Matthew K., McGuire, Jimmy A., Donnellan, Stephen C., and Moritiz, Craig
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BIOGEOGRAPHY ,PHYLOGEOGRAPHY ,NEOGENE paleoecology ,NEOGENE paleoclimatology ,MITOCHONDRIA ,BIOTIC communities - Abstract
Late Neogene aridification in the Southern Hemisphere caused contractions of mesic biota to refugia, similar to the patterns established by glaciation in the Northern Hemisphere, but these episodes also opened up new adaptive zones that spurred range expansion and diversification in arid-adapted lineages. To understand these dynamics, we present a multilocus (nine nuclear introns, one mitochondrial gene) phylogeographic analysis of the Bynoe's gecko ( Heteronotia binoei), a widely distributed complex spanning the tropical monsoon, coastal woodland, and arid zone biomes in Australia. Bayesian phylogenetic analyses, estimates of divergence times, and demographic inferences revealed episodes of diversification in the Pliocene, especially in the tropical monsoon biome, and range expansions in the Pleistocene. Ancestral habitat reconstructions strongly support recent and independent invasions into the arid zone. Our study demonstrates the varied responses to aridification in Australia, including localized persistence of lineages in the tropical monsoonal biome, and repeated invasion of and expansion through newly available arid-zone habitats. These patterns are consistent with those found in other arid environments in the Southern Hemisphere, including the South African succulent karoo and the Chilean lowlands, and highlight the diverse modes of diversification and persistence of Earth's biota during the glacial cycles of the Pliocene and Pleistocene. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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17. NEW SPECIES OF THE LATE CENOZOIC FUNGAL FORM-GENUS MEDIAVERR UNITES JARZEN & ELSIK 1986 EX NANDI & SINHA 2007.
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Elsik, William C. and Jarzen, David M.
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FUNGI ,CENOZOIC palynology ,STENELLA longirostris ,NEOGENE paleoecology ,PALYNOLOGY -- Quaternary ,MIOCENE paleoecology ,NEOCENE stratigraphic geology - Abstract
New species of the fungal form-genus Mediaverrunites Jarzen & Elsik 1986 ex Nandi & Sinha 2007 are described from tropical to warm temperate Neogene strata. Mediaverrunites fournierii sp. nov. and Mediaverrunites magnus sp. nov. occur in the Lower Miocene of Colombia. Mediaverrunites invaginatus sp. nov. is from the Upper Miocene to Lower Pleistocene, offshore Louisiana. The form-genus is also represented by an apparently undescribed extant species occurring in recent sediment. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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18. THE LIFE OF PROFESSOR JOHN H. WRENN.
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Hart, George F. and Webb, Peter
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PALYNOLOGISTS ,DINOFLAGELLATE cysts ,BIOSTRATIGRAPHY ,NEOGENE paleoecology ,NEOCENE stratigraphic geology ,PALYNOLOGY ,CONFERENCES & conventions - Abstract
The article describes the life and works of palynologist John H. Wrenn and captures the essence of his character. It mentions that Wrenn was deeply committed to the American Association of Stratigraphical Palynologists (AASP) for much of his professional life. It stresses that Wrenn was born in Jackson, Michigan, and spent his younger years in Arlington, Illinois. It states that Wrenn's involvement with AASP began in 1986 when he organized and chaired the First Symposium on Neogene Dinoflagellate Cyst Biostratigraphy during AASP's 20th Annual Meeting in New York City.
- Published
- 2009
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19. Phylogeny and systematics of the Orycteropodidae (Mammalia, Tubulidentata).
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Lehmann, Thomas
- Subjects
FOSSIL tubulidentata ,ORYCTEROPODIDAE ,PHYLOGENY ,AFROTHERIANS ,NEOGENE paleoecology ,MIOCENE paleoecology ,CLADISTIC analysis - Abstract
The systematics of the order Tubulidentata is poorly known. Its phylogeny has never been thoroughly analysed and only a single review has ever been performed, which was over 30 years ago. This situation has hampered palaeoecological and palaeobiogeographical studies of these Neogene mammals. The present revision of the Orycteropodidae deals with the phylogeny and systematics of all African and Eurasian species over the last 20 Myr. The first comprehensive cladistic analysis of the family is presented here. The results of this analysis, based on 39 coded morphological characters, supplemented by non-coded features taken from all over the skeleton, was used to reconstruct the phylogeny of the order Tubulidentata. Two distinct lineages within the genus Orycteropus are recognized and characterized. The new genus Amphiorycteropus is subsequently created, in order to harmonize taxonomy and phylogeny. The fossil genera Leptorycteropus and Myorycteropus are validated, bringing the number of genera in the order Tubulidentata to four. Moreover, within the family Orycteropodidae, the number of confirmed species is now 14. The outcome of this study allows us to propose a consistent palaeobiogeographical scenario for aardvarks. Finally, this revision represents the most comprehensive work on the evolutionary history of the order Tubulidentata to date, and provides a new framework for future studies. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155, 649–702. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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20. Phylogenetic relationships of assimineid gastropods of the Death Valley–lower Colorado River region: relicts of a late Neogene marine incursion?
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Hershler, Robert and Hsiu-Ping Liu
- Subjects
SNAILS ,RELICTS (Biology) ,GENES ,PHYLOGENY ,BAYESIAN analysis ,GASTROPODA ,NEOGENE paleoecology ,ANIMALS - Abstract
Aim A small fauna of amphibious snails (genus Assiminea Fleming, 1828) living in association with highly mineralized springs in the Death Valley–lower Colorado River region (DVLCR) is thought to be a relict of the Bouse Embayment, a putative late Miocene–early Pliocene transgression of the ancestral Gulf of California along the lower Colorado River valley. We analysed the phylogenetic relationships of this fauna using mtDNA sequence data (1171 bp) to determine whether, as would be consistent with this hypothesis, it forms a substantially divergent unit sister to marine coastal congeners. Location South-western Great Basin and lower Colorado River region, USA. Methods Two genes [mitochondrial cytochrome c oxidase subunit I (COI) and the mitochondrial 16S ribosomal RNA gene] were sequenced for 10 populations of DVLCR assimineas ( Assiminea infima Berry, 1947 ; Assiminea sp.). We also sequenced an undescribed population from a spring in the Colorado River delta; western North American Pacific Coastal Assiminea californica (Tryon, 1865); the three other congeners that live on the continent; and three Old World assimineids (outgroups). Phylogenies based on the combined data set were obtained using Bayesian methods, and divergence times were estimated using a COI molecular clock for related gastropods. Results Composite haplotypes of the DVLCR assimineas, together with that observed in the Colorado River delta population, formed a weakly supported clade that was sister to a clade composed of populations of North American Pacific and Atlantic coastal species. The genetic distance between members of these two clades was 3.46 ± 0.47% for COI and 1.69 ± 0.38% for 16S. The former clade was composed of five subunits that differed from each other by 1.29–2.84% (COI) and 0.52–1.98% (16S) sequence divergence. Main conclusions Application of the COI clock suggests that progenitors of the DVLCR fauna diverged from coastal ancestors 2.13–1.89 Ma (late Pliocene), several million years after the Bouse Embayment would have been terminated by the establishment of the lower (freshwater) Colorado River. This finding, together with shallow genetic structuring of several DVLCR lineages that are widely distributed across the topographically complex regional landscape, suggests that the Assiminea fauna of this inland area was more likely to have been founded by coastal colonists transported on water birds than through a direct connection with the sea. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
21. RASC/CASC: Example of Creative Application of Statistics in Geology.
- Author
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Di Zhou
- Subjects
NEOCENE stratigraphic geology ,NEOGENE paleoseismology ,NEOGENE paleoceanography ,NEOGENE paleoclimatology ,NEOGENE paleoecology ,FOSSILS ,PALEONTOLOGY ,INTERTIDAL zonation ,SEASHORE biology - Abstract
RASC/CASC is a computer-based system for quantitative stratigraphic analysis developed by Agterberg, Gradstein, and co-workers. The application of the system to the Neogene biostratigraphy of the Pearl River Mouth Basin demonstrates the advantages of the system. The occurrence data of hundreds of fossils from dozens of wells are analyzed objectively based on established stratigraphic and statistical rules embedded in the system. Through permutation of the score matrix, the optimum sequence of fossil events is obtained. The calculation of inter-fossil distances allows the automated biostratigraphic zonation and the age-event correlation. Then the regional geological timetable is constructed and the interwell chronological correlation and high-resolution subsidence analysis becomes possible, even for wells with incomplete fossil records. Uncertainty at each step is quantified. While all these are important accomplishments in a stratigraphic study, results of the study also help identify problems in allocation of fossil events and dating lithologic divisions. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
22. Control of strike-slip faulting on reservoir formation of oil and gas in Nanpu sag
- Author
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DONG, Yue-xia, WANG, Ze-cheng, ZHENG, Hong-ju, and Xu, An-na
- Subjects
PETROLEUM industry ,NEOGENE paleoecology ,NEOGENE paleoseismology ,NATURAL gas migration - Abstract
Abstract: According to the data of seism, gravity, drilling etc, this article reexamines the Baigezhuang fracture and the Xi''nanzhuang fracture and analyzes the control of structural deformation on the hydrocarbon accumulation in the Nanpu sag. The Baigezhuang and Xi''nanzhuang fractures merged into a base strike-slip fracture, which had distinct left strike-slip at the Yanshan stage lasting until the Es stage and controlled the Es deposition. The Paleogene basin-forming in the Nanpu sag was controlled by the left strike-slip Baigezhuang-Xi''nanzhuang base fracture with the Nanpu sag as a strike-slip stretching sag. The NE and NW strike-slip fault belts with conjugate shearing were formed by the Neogene fault strike slipping and controlled the distribution of secondary structural belts. The substantial hydrocarbon accumulation in the Nanpu sag has matched in time with the Neogene fault movement, which is favorable to oil and gas migration and trap formation, therefore, the oil and gas are distributed vertically along fault belts as multiple layers. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
23. Morphology and phylogenetic relationships of a new eschrichtiid genus (Cetacea: Mysticeti) from the Early Pliocene of northern Italy.
- Author
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BISCONTI, MICHELANGELO
- Subjects
BALEEN whales ,FOSSIL classification ,ANIMAL morphology ,NEOGENE paleoecology ,BIODIVERSITY ,SCIENTIFIC method - Abstract
A new eschrichtiid, Eschrichtioides gastaldii gen. nov., comb. nov., is established based on a specimen previously assigned to Balaenoptera gastaldii Portis, 1885. The holotype is from the Early Pliocene of north-east Italy. It represents a fossil mysticete closely related to the living grey whale, Eschrichtius robustus. Comparative morphology and phylogenetic analysis support the monophyly of Eschrichtiidae and Cetotherium-like mysticetes and a sister group relationship between this clade and Balaenopteridae. Eschrichtiid fossils previously described are all from the Pleistocene and Late Pliocene while Eschrichtioides gastaldii is from the Early Pliocene. The recognition of this new eschrichtiid genus suggests that the Mediterranean trophic web of the Early Pliocene was more complex than at present and that the Neogene mysticete family-level biodiversity of the Mediterranean was higher than that currently observed in this basin. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 153, 161–186. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
24. Petroleum geology and exploration of beach sandbar in Junggar Basin, NW China: A case from Shawan Formation in Well Pai 2
- Author
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XIANG, Kui, BAO, Zhi-dong, and ZHUANG, Wen-shan
- Subjects
NEOGENE paleoclimatology ,NEOGENE paleoecology ,MINE valuation ,NEOGENE paleoseismology ,NEOCENE stratigraphic geology - Abstract
Abstract: Well Pai 2 is located at the Chepaizi high relief belt, west Junggar Basin. The Neogene Shawan Formation beach sandbar in the Well Pai 2 is developed by lake wave reconstruction of fan-delta and reworking in its frontal side or flank, which was caused by lake transgression and fan oscillation on the basin slope, in the continuously dextral and uplifting of Chepaizi relief and under the compression background during evolution of the Tertiary quasi-foreland basin. Depositional and electric characteristics of the beach sandbar are characterized by fine, loose grains, small thickness, two-stage cumulative probability curve, C-M chart showing PQRS paragraph mainly, moderate compositional and textural maturity, dactyline self-potential curve, and semi-funnel-shaped resistivity curve. After light oil charging, the beach sandbar reservoir show high amplitude, low-to-moderate frequency, and high absorption coefficient, and its energy amplitude shows clear boundary, convex top, and flat bottom. Beach sandbar has prospects for good physical properties and lithologic reservoirs. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
25. Paleogene and Neogene strata in Northeastern Asia: paleocarpological background
- Author
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Nikitin, V.P.
- Subjects
PALEOGENE stratigraphic geology ,NEOGENE paleoecology ,FOSSIL plants ,PALEONTOLOGY - Abstract
Abstract: Fossil seed assemblages of Paleogene and Neogene strata in northeastern Asia are reviewed based on data of Novosibirsk paleocarpologists and literature data. The composition and age of flora are refined, and recommendations on improving stratigraphic charts of deposits in northeastern Russia are given. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
26. ANATOMICAL REVISION OF THE GENUS MERYCOPOTAMUS (ARTIODACTYLA; ANTHRACOTHERIIDAE): ITS SIGNIFICANCE FOR LATE MIOCENE MAMMAL DISPERSAL IN ASIA.
- Author
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Lihoreau, F., Barry, J., Blondel, C., Chaimanee, Y., Jaeger, J.-J., and Brunet, M.
- Subjects
NEOGENE paleoecology ,MIOCENE paleoecology ,ARTIODACTYLA ,MAMMALS - Abstract
New fossil remains of the anthracothere genus Merycopotamus Falconer and Cautley, are described. Most of them were discovered by the Harvard University and Geological Survey of Pakistan joint research project (Y-GSP) in the well-dated Middle and Late Miocene deposits of the Potwar Plateau in northern Pakistan. This new material led us to revise the systematics of the genus with the validation of three species, M. nanus Falconer ( M. pusillus Lydekker), M. dissimilis Falconer and Cautley, and M. medioximus Lihoreau et al., and allowed us to determine precisely their chronological distributions in a continuous Neogene sequence. Other specimens reported from the late Miocene deposits of the Khorat Plateau in north-east Thailand by the Department of Mineral Resources are the first remains of Merycopotamus to have been discovered in that region and are attributed to M. medioximus. These discoveries indicate a wider geographical distribution of the genus in the early Late Miocene. Anatomical investigations highlight the evolution of Merycopotamus through the Miocene towards more amphibious habits. Palaeobiogeographical and palaeoecological information for Merycopotamus stress the role of the Himalayan orogenesis as a dispersal barrier and the impact of a major global regression event on the evolution of Indian Subcontinent faunas from the Middle Miocene to the Late Pliocene. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
27. Neogene paleoclimatic changes in response to tectonism in the Himalayan Gyirong Basin, China.
- Author
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Xu, Yadong, Zhang, Kexin, Wang, Guocan, Jiang, Shangsong, Xiang, Shuyuan, Chen, Fenning, Hoorn, Carina, and Dupont-Nivet, Guillaume
- Subjects
PALEOCLIMATOLOGY ,GEOLOGICAL basins ,NEOGENE paleoecology ,NEOGENE Period ,CLIMATE change - Abstract
The article explores paleoclimatic changes in the Gyirong Basin of China. It notes the Neogene sequence of the Hipparion fauna, molluscs, ostracods and pollen found in the basin. The paleoenvironmental changes identified in the area are paleo-current of alluvial-fan lithofacies, paleo-current of the fluvial-lacustrine lithofacies and paleo-current of the lacustrine-fan delta lithofacies. It also notes that the cooling trend indicate an interplay between tectonism and climatic changes.
- Published
- 2012
- Full Text
- View/download PDF
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