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1.
Claudio Arias Giulio Bigazzi Francescopaolo Bonadonna Karl Brunnacker Brigitte Urban 《Quaternary Science Reviews》1984,3(1):73-89
Biostratigraphic and palaeomagnetic research has been carried out on selected profiles in North-Western Germany and Central Italy in order to correlate Plio-Pleistocene sections.Around the Réunion subchronozone, vegetation in the Valle Ricca was dominated by a mountain forest type pointing to cool climatic conditions. In the Lower Rhine Basin vegetation had a slightly warmer character, but was also dominated strongly by a mountain type of forest vegetation, characteristic of cooler summers and higher precipitation than at present.Two warmer periods have been determined in the Central Italian profiles; the youngest around the Olduvai reversal, should correspond to the youngest Tiglian beds of the Lower Rhine Basin.Deposits older than the Réunion subzone have not been found in the Valle Ricca. In the Lower Rhine Basin, on the other hand, the Gauss-Matuyama boundary is located between the uppermost Pliocene, the Reuverian C and the Praetiglian. 相似文献
2.
In this paper, the currently accepted correlation of the Early Pleistocene Ludhamian stage of England with the Tiglian‐A sub‐stage of the Netherlands is challenged. Recent investigations of Early Pleistocene marine North Sea deposits from a borehole near Noordwijk (the Netherlands) yielded evidence from molluscs, dinoflagellate cysts and sporomorphs for an alternation of warm‐temperate and arctic intervals within the Praetiglian and Tiglian stages. Marine equivalents of the terrestrial‐based pollen sub‐stages Tiglian A and B have been recognised in the upper part of the sequence. A Praetiglian age can be assigned to the lower part of the sequence on the basis of mollusc analysis. Within the Praetiglian, an alternation of warm and cold phases has been recognised from both the dinoflagellate cyst and molluscan records. Three cold phases within the Praetiglian are tentatively correlated with marine isotope stages (MIS) 96–100. The molluscan assemblages provide evidence for climate forcing of the sea level: highest sea levels are reached in the warm‐temperate intervals. Within the Praetiglian, an interval with an acme zone of the dinoflagellate cyst Impagidinium multiplexum, is correlated with the Ludhamian and tentatively linked to MIS 97 and/or MIS 96. The cold molluscan assemblages from the Noordwijk borehole include an acme zone of Megayoldia thraciaeformis, the first and only occurrence of this North Pacific bivalve in the North Sea Basin. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
3.
The Pliocene-Pleistocene boundary, defined using pollen analysis, has been recorded in sections at the Belchatów outcrop, Kleszczów Graben, central Poland. The boundary is located at the top of the green clay subunit of the Tertiary Clayey-sandy unit. A pollen flora of Reuverian C type, dominated by pine, 10–20% of ‘Reuverian elements’ and scarce thermophilous Tertiary trees, was found directly below this subunit. Cold stage floras of Praetiglian type were, in turn, recorded in the ?ekińsko Formation, lying directly on the green clays. The Pliocene—Pleistocene transition at Belchatów demonstrates the characteristic features of this boundary in western Europe, that is, the disappearance of Tertiary thermophilous tree pollen taxa, followed by a cooling to open-forest or forest-steppe conditions. Both pollen analysis and geological data suggest continuous sedimentation at least from the Upper Pliocene to the Prae-Tiglian, with no change of sediment sources and no marked hiatuses. The fluvial deposits of the Praetiglian ?ekińsko Formation, although Pleistocene in age, mark a final period in the Tertiary evolution of the Kleszczów Graben. Later, there is a hiatus to the deposition of the first glacigenic sediments in the region possibly of Elsterian age. 相似文献
4.
《Earth》2008,86(3-4):161-186
Pollen records from fluvial deposits in The Netherlands have traditionally been used to establish continental stages for the Neogene in NW Europe. These stages are still widely used across Europe for stratigraphic correlations and palaeoclimatic studies. Despite their extensive use, the validity of this continental correlation scheme for the Plio- and Pleistocene has never been tested in the area where they were originally proposed: the Roer Valley Graben (RVG). The fluvial and deltaic depositional setting in this area is controlled by a complex pattern of tectonic and climatic processes, which strongly complicates the definition of stages and sub-stages of regional or supra-regional significance.Here, the original palynological data used to define the Praetiglian, Reuverian, Brunssumian, Susterian, and ‘Linne’ (sub-)stages are assessed and compared to new borehole data. With a multivariate (Correspondence Analysis) approach we show that most of these stages cannot be distinguished by numerical analysis of the pollen assemblages. A tripartition of pollen assemblages is possible, which results in a cooler Pleistocene cluster, warm-temperate to sub-tropical Pliocene cluster, and a warm and relatively dry Late Miocene to Early Pliocene cluster. However, no further stages, sub-stages or clear climatic phases can be consistently recognized in these data.A detailed lithostratigraphic framework of the study area allows a correlation of the sections independent of the pollen data. Results confirm the numerical analyses and furthermore point to a strong lithological (depositional) bias on the pollen assemblages. Variations in the abundance of Sequoia and Taxodium, originally used to define the Brunssumian/Reuverian transition and Brunssumian A–C sub-stages, are shown to represent mostly local changes. The number and absolute percentage of the fluctuations in Sequoia and Taxodium abundances depend largely on the sample resolution and the site location within the RVG.Our data assessment indicates that long-distance chronostratigraphic correlations based on the original continental Neogene stages likely are invalid. Furthermore, the palaeoclimatic reconstructions that have been based on the RVG successions are largely over-interpreted. The present palaeoclimate reconstructions from the RVG reflect variations in the highly-dynamic fluvial depositional setting, taphonomic effects and environmental conditions, including climate. A sequence-stratigraphic approach combined with the analysis of interfingering marine sediments is potentially better suited to establish absolute ages and associated climatic conditions of the Neogene deposits within the RVG. 相似文献
5.
JEAN-PIERRE SUC WALDO H. ZAGWIJN 《Boreas: An International Journal of Quaternary Research》1983,12(3):153-166
During the Last Glacial, a very open vegetation existed over western Europe, the tundra-like vegetation in The Netherlands evolving into a stcppic-like vegetation towards the Mediterranean. This model was used to analyse the correlation of the Praetiglian (dated from 2.3 to 2.1 million years ago) in northern Europe with the earliest steppic phase in the Mediterranean region. On this basis, stratigraphic relationships between these two areas are postulated for the whole Pliocene and the Early Pleistocene in terms of the vcgctational changes related to the climatic fluctuations. For the first time, correlation has been shown between the palynostratigraphy of northern Europe and the Late Neogcnc marine stratigraphy of the Mediterranean region; moreover, chronological confirmation is supplied by the mammal zonation. the evolution of stratiotes, palaeomagnetic measurements, and K/Ar dates. The conventional Plio-Pleistocenc boundary occurs during the first interglacial (Tiglian) of northern Europe. 相似文献
6.
MARIE-THÉRÈSE MORZADEC-KERFOURN 《Boreas: An International Journal of Quaternary Research》1977,6(3):275-283
The end of the Pliocene transgression is represented in Brittany, above sands and gravels, by clay or sandy clay containing an estuarian plankton and sometimes shells of molluses.
New borings at Pont-Rouz in Quemperven (Brittany) permit a biostratigraphical study, by means of pollen analysis, of the period corresponding to the Pliocene-Pleistocene transition. In the lower part of the deposit, rich in Ostrea shells, many floral element characteristics of the Reuver-clay are present: Sequoia, Taxodium, Sciadopitys , in relatively high percentages, Nyssa, Symplocos, Liquidambar , sporadically. The 'Tertiary' elements disappear in the upper part of the clay when other relicts like Tsuga, Pterocarya , and Carya are still present. Thus the Reuverian-Praetiglian boundary can be traced in the littoral sequence of Pont-Rouz. As in the Netherlands, the deterioration of the climate is clearly indicated by a sudden increase of Graminaceae pollen. A same evolution of the flora can be noticed at Mernel and Saint-Jean-la-Poterie, also in grey clay, along the river system of the Vilaine.
The Upper-Pliocene transgression has followed the same river system as the present one. The estuarian sediments lie in Brittany between 55 and 30 metres above zero NGF. The maximum of the transgression is situated in the Reuverian at La Salle, near Pont-Rouz, at 55 m (NGF). The post-Pliocene regression begins with the Praetiglian and continues in the Lower Pleistocene. 相似文献
New borings at Pont-Rouz in Quemperven (Brittany) permit a biostratigraphical study, by means of pollen analysis, of the period corresponding to the Pliocene-Pleistocene transition. In the lower part of the deposit, rich in Ostrea shells, many floral element characteristics of the Reuver-clay are present: Sequoia, Taxodium, Sciadopitys , in relatively high percentages, Nyssa, Symplocos, Liquidambar , sporadically. The 'Tertiary' elements disappear in the upper part of the clay when other relicts like Tsuga, Pterocarya , and Carya are still present. Thus the Reuverian-Praetiglian boundary can be traced in the littoral sequence of Pont-Rouz. As in the Netherlands, the deterioration of the climate is clearly indicated by a sudden increase of Graminaceae pollen. A same evolution of the flora can be noticed at Mernel and Saint-Jean-la-Poterie, also in grey clay, along the river system of the Vilaine.
The Upper-Pliocene transgression has followed the same river system as the present one. The estuarian sediments lie in Brittany between 55 and 30 metres above zero NGF. The maximum of the transgression is situated in the Reuverian at La Salle, near Pont-Rouz, at 55 m (NGF). The post-Pliocene regression begins with the Praetiglian and continues in the Lower Pleistocene. 相似文献
7.
Major palaeohydrographic changes in Alpine foreland during the Pliocene - Pleistocene 总被引：1，自引：0，他引：1
CHRISTOPHE PETIT MICHEL CAMPY JEAN CHALINE JACQUES BONVALOT 《Boreas: An International Journal of Quaternary Research》1996,25(2):131-143
The changing palaeogeographical pattern of Alpine deposits across the European forelands can be traced by identifying mineral assemblages and establishing the chronology of Pliocene-Pleistocene deposits in Alpine foreland. In the late Miocene, the upper courses of the Rhine and the Aar flowed east from the Swiss molasse plain towards the Danube. In the early Pliocene (Brunssumian, 5-3.2 Ma), these same rivers headed north wards towards the Rhine Graben of Alsace. In the early Reuverian, these streams were captured south of the Rhine Graben by the Doubs. They ceased their northward flow and headed west to feed the Bresse Graben. This phase is dated to the Lower and Middle Reuverian (3.2-2.6 Ma). From the Upper Reuverian (2.6 Ma) to the present day, the Rhine has adapted approximately its present course towards the North Sea, south to north along the Rhine Graben and across the Rhine Schist Massif to feed the Dutch Grabens. This changing pattern of capture and alteration of the hydrographic system of the upper reaches of the Rhine and the Aar can be explained by local tectonic movements. 相似文献
8.
Pleistocene deposits, together with their pollen, plant macrofossil, foraminiferal, dinoflagellate and coleopteran remains, from five sites along the Atlantic coast of the Médoc Peninsula are described and discussed. Sediments making up the Négade Formation are shown to have been laid down under either estuarine or lagoonal conditions when closed Quercus–Pinus‐Tsuga canadensis regional woodland existed. Comparison with plant records from The Netherlands indicates that these deposits are most likely attributable to either the Early Pleistocene Bavel Interglacial (marine oxygen isotope stage (MIS) 31), or an interglacial of the Waalian (MIS 37–49) or Tiglian (MIS 63–79). In addition, clays assigned to the Argiles du Gurp sensu stricto, were similarly deposited in either an estuary or lagoon, which subsequently was cut off from the sea. A freshwater lake with vegetation dominated by Azolla filiculoides then developed. This was succeeded by reedswamp and an organic mud (termed Lignite in the corresponding French stratigraphical records) formed. Regional Quercus–Abies woodland was replaced by one with Pinus dominant and Pterocarya a minor component. Comparison with plant records from France and other parts of Europe suggest that the clays and organic mud might be correlated with the Holsteinian (Praclaux) Interglacial (MIS 11c). Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
9.
The drilling of new cores performed for ANDRA in eastern France allowed us to compare palynological data between central and eastern parts of the Paris Basin. Such a comparison, which was also motivated by the existence of a set of geochemical data in contradiction with the first palynological results, showed a spatial differentiation in palynological record from the Oxfordian. Such a palynological signal could result from overlapping of both local and global signals, the latter being in connection with the contemporaneous opening of proto-Atlantic Ocean. It could also be of major palaeogeographic and palaeoclimatic interest. To cite this article: V. Huault et al., C. R. Geoscience 335 (2003). 相似文献
10.
Federica Marcolini 《Mathematical Geosciences》2006,38(6):667-678
Fourier analysis was used in this study to help a specific determination of some Mimomys (Arvicolidae, Rodentia, Mammalia) species. Several Pliocene and Pleistocene Central and Western European Mimomys species first lower molar contours have been decomposed by Complex Discrete Fourier Transform. Inter- and intra-specific comparisons have been performed on the harmonics obtained from the decomposition and some problematic specimens have been classified. 相似文献
11.
Federica Marcolini 《Mathematical Geology》2006,38(6):667-678
Fourier analysis was used in this study to help a specific determination of some Mimomys (Arvicolidae, Rodentia, Mammalia)
species. Several Pliocene and Pleistocene Central and Western European Mimomys species first lower molar contours have been
decomposed by Complex Discrete Fourier Transform. Inter- and intra-specific comparisons have been performed on the harmonics
obtained from the decomposition and some problematic specimens have been classified. 相似文献
12.
The Kas Formation in SE Turkey was deposited as part of the Permian sequence on the northern margin of the Arabian Plate. Its stratigraphic relationship to time‐equivalent strata of the Arabian Plate was mentioned briefly in previous studies, but has not been elaborated and illustrated in detail. This biostratigraphic review of existing palaeontological data has improved the accuracy of age interpretation for the Kas Formation, and the relationship of its excellent palynological record to the international Permian chronostratigraphic units. As a result, this study has identified a number of key palynological species from the Kas Formation, which occur as well as in the ‘Basal Khuff Clastics’ of Saudi Arabia and in the ‘Khuff transition section’ of Oman. All these units have approximately the same age: Wordian to early Capitanian, based on ‘age control’ provided by Foraminifera. This study also demonstrates that, by using key palynological taxa, correlation of strata would be possible across the entire Arabian Plate in this narrow time range. Hence, the ‘Oman and Saudi Arabia Palynological Zone 6’ (OSPZ6) is applicable throughout the Arabian Plate area, including the northern regions of SE Turkey and Iraq. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
13.
A new Cenozoic dataset in the subsurface of the South Flank of the Golfo San Jorge Basin (Santa Cruz province) allowed to identify a non-previously recognized transgressive event of late Eocene to early Oligocene age. Below of a marine succession containing a dinoflagellate cyst assemblage that characterizes the C/G palynological zone of the Chenque Formation (early Miocene), a 80–110 m thick marine succession contains a palynological assemblage integrated by Gelatia inflata, Diphyes colligerum and Reticulatosphaera actinocoronata supporting the occurrence of a marine incursion in the basin during the Eocene–Oligocene transition (EOT). The new lithostratigraphic unit - here defined as El Huemul Formation – covers in sharp contact to the Sarmiento Formation, and become thinner from East to West; the unit has been identified in about 1800 well logs covering up to 3500 km2, and its subsurface distribution exceed the boundaries of the study area. The El Huemul Formation consists of a thin lag of glauconitic sandstones with fining-upward log motif, followed by a mudstone-dominated succession that coarsening-upward to sandstones, evidencing a full T-R cycle. Preservation of the El Huemul Formation in the subsurface of the South Flank has been favored by the reactivation of WNW-ESE late Cretaceous normal faults, and by the generation of N–S striking normal faults of Paleocene-Eocene age. Flexural loading associated to igneous intrusions of Paleocene?- middle Eocene age also promoted the increase of subsidence in the South Flank of the basin prior to the transgression. 相似文献
14.
《Journal of South American Earth Sciences》2005,18(2):199-212
The Pinturas Formation is a continental succession, characterized by eolian sediments (mainly tuffaceous) and paleosols, originated in an upland setting of west central Patagonia. The main intraformational erosive surfaces and lithological changes define three sequences. The Formation bears a rich mammalian association (Florentino Ameghino's Astrapothericulan fauna), whose age in relation to the Santacrucian SALMA (middle Miocene) is still controversial. Recent collections from the Pinturas Formation, performed with stratigraphic control, allow differentiation of two distinct hystricognath rodent associations. The lower and middle sequences bear a particular combination of Colhuehuapian (early Miocene) and Santacrucian genera, mostly represented by species exclusively known to the Pinturas Formation (‘Pinturan’ association). The upper sequence bears typical Santacrucian species, more derived than its Pinturan counterparts. According to the rodent record, the lower and middle sequences of the Pinturas Formation are older than the base of the Santa Cruz Formation exposed at Monte Observación and Monte León, and the upper sequence may be correlated with the lowermost levels of the Santa Cruz Formation and deposits exposed at Karaiken that bear Ameghino's ‘Notohippidian’ fauna. These correlations agree with more recent radiometric dates and other biostratigraphic evidence, supporting Ameghino's original hypothesis. The Pinturan rodent assemblage of the lower and middle sequences suggests the presence of humid forests, in accordance with other faunal components and palynological data. Sedimentologic, paleopedologic, and ichnologic evidence, however, suggest environments dominated by herbaceous vegetation. This seeming contradiction is interpreted as the result of a marked environmental gradient due to the paleotopography and/or climatic fluctuations. The mammal record corresponds to the more humid intervals, which have less representation in the sedimentary record. The Pinturas case reveals that more detailed analyses are necessary to understand the relationship between the stressed abiotic Patagonian scenarios and the evolution of their Tertiary vertebrate communities. 相似文献
15.
青海省同仁县古浪堤中上三叠统古浪堤组孢粉组合及其地层意义 总被引：3，自引：0，他引：3
经过对青海同仁县古浪堤组实测剖面的17块样品做孢粉分析, 在6个层位样品中见有孢粉化石30属41种, 据此在该剖面自下而上划分2个孢粉组合:Dictyophyllidites-Di-saccus组合和Verrucosisporites-Di-saccus组合.上述孢粉组合中的孢粉的优势属为Dictyophyllidites, Cyathidites, Verrucosisporites和Chasmatosporites, Protopicea, Pinuspollenites.其中, Dictyophyllidites频繁出现于欧亚、北美、大洋州的晚三叠世和早侏罗世组合, Aratrisporites在南半球大量发育于中三叠世, Asseretospora在澳大利亚的分布时期是中三叠世-早侏罗世.前人于黄南的阿龙江上游及柴陇沟北, 古浪堤组产卡尼期的菊石Protrachycerassp.及双壳类Eumorphotis (Asoella) cf.illyrica.综合而言, 该地区古浪堤组时代厘定为中-晚三叠世, 古植物群生长于暖温带-亚热带河控三角洲环境. 相似文献
16.
吉隆盆地为高喜马拉雅中新世晚期约10 Ma时期形成的一个南北向断陷盆地, 其东侧为同沉积正断层, 沃马剖面位于盆地沉降中心的东南部.在该剖面下部新发现一套中新世巨厚砾岩层(旦增竹康组).通过锆石和磷灰石裂变径迹年代学研究得出吉隆盆地控盆断裂早期活动时间为13.4±1.9 Ma, 源区12~11 Ma发生构造热事件, 据此推算出吉隆盆地初始裂陷后开始沉积的底界年龄约为10 Ma.综合前人在吉隆盆地得出的7.20~1.67 Ma古地磁测年值, 可得出吉隆盆地旦增竹康组年龄为10.0~7.4 Ma, 沃马组年龄为7.40~1.67 Ma.根据孢粉组合带和孢粉组合反映的植物类型和古环境变化, 沿剖面自下而上划分为3个孢粉组合带和9个孢粉组合及其对应的植被类型.吉隆地区古气候变化可划分为3个阶段: (1)组合带Ⅰ和孢粉组合1~2, 为温暖偏干环境的常绿与落叶针阔叶混交林, 地层对比时代为晚中新世(10.0~7.0 Ma); (2)组合带Ⅱ和孢粉组合3~7, 为寒冷干旱环境的落叶针叶林, 期间存在一次暖湿气候的波动, 地层对比时代为晚中新世晚期-早上新世(7.0~3.3 Ma); (3)组合带Ⅲ和孢粉组合8~9, 为温凉偏干的气候下生长暗针叶林和落叶阔叶林构成的针阔叶混交林, 地层对比时代为晚上新世(3.30~1.67 Ma). 相似文献
17.
Major river systems of central and southern Britain during the Early and Middle Pleistocene 总被引：1，自引：0，他引：1
Central and southern Britain was drained by two main river systems during the larger part of the Early and Middle Pleistocene: the Thames and Bytham rivers. Evidence for these rivers and their Quaternary history is represented by their sediments (the Kesgrave and Bytham Sands and Gravels, respectively), the geomorphological position of the sediments, biostratigraphy and amino acid geochronology. Evidence from the earlier parts of the Early Pleistocene (Tiglian C4b and earlier) indicates low-energy river systems and marine conditions over much of East Anglia. For most of the Early Pleistocene (Tiglian C4c to the Cromerian Complex) the ancestral Thames was the main river with, at its maximal extent, a catchment that extended into Wales, and across East Anglia and what is now the North Sea, to join the ancestral Rhine. During this period, glaciers in the uplands of Wales and periglacial mass movement elsewhere supplied material to the catchment and it was at this time that the bulk of the sorted Quaternary ssediments of lowland Britain were deposited. The Bytham river system has no successor because the landscape now in existence has been fundamentally altered by glacial erosion. This catchment drained most of Midland England and joined the Thames in central East Anglia. Initially, the Bytham river was a tributary of the Thames, but over time it extended its catchment and at the beginning of the 'Cromerian Complex'it became the main river of southern Britain. With the Anglian Glaciation (01 Stage 121, the Bytham river was destroyed and the Thames was diverted to its present route through London. 相似文献
18.
四棵树凹陷位于准噶尔盆地南缘西段乌苏市境内,蕴含丰富的油气和煤炭资源。由于匮乏化石证据,制约四棵树凹陷侏罗纪地层的地质时代的确定。对西山窑组沉积环境和孢粉分析研究,恢复重建了其古环境,探讨了本区中西山窑时期的植被演替及环境演变。西山窑组岩性以泥质细砂岩、浅灰绿色泥岩、粉砂岩、泥岩为主。通过对孢粉化石分析研究,建立了Cyathidites minor—Osmundacidites —Cycadopites—Disacciatrileti（COCD）孢粉组合。组合中蕨类植物孢子与裸子植物花粉含量大体相当,蕨类植物孢子以紫萁科的Osmundacidites为主,桫椤科孢子也有一定含量,其他常见分子包括Deltoidospora、Neoraistrickia等,裸子植物以松柏类两气囊花粉含量为主,均为我国侏罗纪常见属种。通过对西山窑组孢粉植物群的分析,认为西山窑组孢粉组合时代属于中侏罗世早期,该孢粉植物群总体上反映了温暖湿润的热带—亚热带气候特点,植被类型以针阔混交林为主。 相似文献
19.