Geomorphology of the Environments of Říp and Mělník (Central Bohemia)

The Boiano Basin is one of the largest Quaternary intermontane basins of the central‐southern Apennines within one of the most tectonically active areas of the Mediterranean region. In order to reconstruct its entire Quaternary stratigraphic, tectonic, and palaeoenvironment evolution, lithofacies and palaeomagnetic analyses have been performed on a 900 m‐deep borehole (CP1) drilled in the southwestern sector of the basin. The Quaternary succession consists of an alternating of alluvial fan and fluvial–marshy deposits for a total thickness of 240 m, unconformably laying on Lower Miocene deposits of the Sannio Unit, thrusted on upper Miocene deposits of the Molise Flysch. In addition, the stratigraphic study and facies distribution of 29 intermediate and shallow wells drilled in the basin, allowing us to define the thickness and lithofacies variations of the Quaternary sedimentary units inside the entire Boiano Basin in the sector of Campochiaro alluvial fan. Our results demonstrate that the Boiano Basin infilling started during the late Early Pleistocene (c. 1.1 Ma) and developed with variation in lithofacies distribution and thickness. The first depositional unit (Early Pleistocene–early Middle Pleistocene in age) was palustrine and fluvial–marshy, the second (Middle Pleistocene in age) was characterized by the occurrence of the first cycle of alluvial fan deposition, the third (late Middle Pleistocene in age) was newly palustrine and fluvial marshy and, finally, the fourth recorded two cycles of alluvial fan deposition (late Middle Pleistocene and Late Pleistocene in age, respectively), interspersed by short periods of palustrinity, tephra layers deposition, and palaeosols development. The study allows the hypothesizing that the Quaternary infilling was accommodated within a graben (or semigraben) structure, affected mainly by extensional fault systems localized in the inner part of the basin and secondly by fault systems bounding the basin.

River valleys of Volhynian Upland are characterized by a larger number of terraces and a greater depth of their downcutting compared with neighbouring Polissia and Male Polissia. We established that the major rivers of Volhynian Upland have floodplain and mostly three terraces. The valley of the Horyn River is different from others by presence of fourth terrace. According to received information, the age of forming of the highest terrace (revealed only in the Horyn Valley) can be considered as Early Pleistocene, the third terrace – Middle Pleistocene, and the two lowest terraces – Late Pleistocene. Relief of the Early and Middle Pleistocene terraces is characterized by high degree of dissection and presence of sufficiently thick loess cover. At higher Late Pleistocene terrace loess cover isn’t revealed everywhere and has a small thickness (typically up to 5 m). The lowest terrace in most valleys has local distribution and it is composed mainly of sandy material. The surface of this terrace is located on several hypsometric levels. Floodplain usually has two high-rise levels. It formed in the Holocene. Key words: river valley, terrace, floodplain, Volhynian Upland, Horyn River, Styr River, Zakhidnyi Buh River.

River terrace deposits are excellent archives of paleoenvironmental conditions. They reflect the tectonic and climatic settings of their time of formation. For this reason, Late-Pleistocene and Holocene terraces have been previously studied in detail because of their good state of preservation and age control. However, less is known about the Middle- and Early-Pleistocene terraces. The Lower Meuse River, a major tributary of the Rhine River, located in the Southern Netherlands, exhibits a well-preserved terrace staircase which, for decades, has been intensely investigated. Age constraints are available, which are mainly based on correlations to the marine isotope record. As of late, the availability of numerical ages of these terraces have been increasing, allowing for a better determination of the boundaries of the Early, Middle and Late Pleistocene terraces. In order to better understand the effects of the Mid-Pleistocene Transition (MPT; 1.2 – 0.8 Ma) in the Meuse River, we improved the spatial and temporal resolution of the terraces of the Lower Meuse. For the spatial resolution, we used a dense borehole database to characterize key geometrical and compositional parameters of the different terrace levels. For the temporal resolution, we used cosmogenic-nuclide geochronological methods, relying on the measurements of the paired isotopes 26Al-10Be, allowing for the estimation of terraces burial age. In this work we outline general spatial trends of geometrical and compositional parameters of terraces formed pre-, syn-, and post-MPT. These results are displayed in an improved time framework that relies upon the new burial ages results from the cosmogenic nuclides concentration measured for specific terrace levels. We present three new isochron-burial ages from Main Terrace levels, and thirteen new simple-burial ages from Middle-, Main-, and East Meuse-Terraces. The results allow us to better understand the signal propagation generated by the MPT. A general increasing trend in the gravel content and terrace thickness have been observed from older to younger terraces. The ages are mostly in good agreement (within uncertainty) with previously proposed age models, especially the ages for the East Meuse Terraces, which have been confirmed to be Early Pleistocene.

The current study focuses on the emblematic Myopus/Lemmus species complex (tribe Lemmini) in the European Pleistocene fossil record. The members of the two genera occupy distinct ecological niches and have different external appearances, but they are remarkably similar in their dental morphology, so that they were commonly thought of as undistinguishable in the fossil record. Thus, more or less all European Lemmini fossils have been assigned to the genus Lemmus. In the Early Pleistocene site of Schernfeld (Germany), the species Lemmus kowalskii had been described. It was thought by some authors that all Lemmini from Early to late Middle Pleistocene belong to this species.In the current study, we investigated Lemmini molar morphology from Western and Central European sites including Schernfeld (Early Pleistocene), Sackdillinger Höhle (Sackdilling Cave), and Koněprusy C718 (both early Middle Pleistocene), as well as other fossil localities with fewer specimens, formerly assigned to Lemmus kowalskii. Using an extensive modern referential material of Lemmus and Myopus, this study proposes to re-evaluate taxonomic status of the Middle and Early Pleistocene Lemmini. This modern referential also allows a better understanding of the morphology of Lemmus kowalskii specimens and its variability.Our results highlight the very high variation within fossil populations, as well as significant statistical differences between populations of the Early and Middle Pleistocene localities. A large part of these fossil specimens is firmly identified as Myopus sp., including the L. kowalskii holotype. Our identifications demonstrate that in most Early and Middle Pleistocene sites considered in this study, both genera (Lemmus and Myopus) are present. Possible interpretations and consequences for current view of lemming history are discussed, as well as some of the paleoecological and paleoenvironmental implications.

The Nara basin, located in the central part of the Kinki triangle in central Japan, mainly consists of Plio-Pleistocene sediments (Osaka group), Pleistocene terrace deposits, and Holocene alluvial deposits.The upper most part of the Osaka group extending in this area consist of fluvial deposits, and is correlated with the Ma3, which is includes the Azuki tephra.The terrace surfaces have developed along the eastern foot of the Kongo-katsuragi Range, in the southwestern part of the basin. Based on the distribution of surface heights and stratigraphies, these terraces are classified into the H, Ml, M2, M3, Li, and L2 surfaces in descending order.The Kongo fault system striking in the north-south direction extends along the eastern foot of the Kongo-katsuragi Range. This fault system consists of the Yamaguchi, Kongo, Nakato, and Yamada faults. These faults have displaced fluvial terrace surfaces, and the slip rates of the vertical component are about 0.03-0.3 m/ky.The Median Tectonic Line striking in the west-east direction and extending southward of the Nara basin, separates the Izumi Range and the Kinokawa lowland. The Shobudani fault, one of the fault systems of the Median Tectonic Line, had a tendency of reverse faulting activity in the former half of the Quaternary. On the contrary, right lateral faulting activity of the Gojodani fault started from the middle Pleistocene, and this tectonic movement has continued to the present along the Median Tectonic Line.Based on the stratigraphy of the Osaka group and fault activity around the study area, the fact that the Nara basin was divided from the Kinokawa lowland by reverse faulting of the Shoubudani fault at least the early Pleistocene, was, clarified. This faulting also formed the, present drainage pattern and the watershed located in the southwestern part of the Nara basin.Fault activity of the Kongo fault system started after the middle Pleistocene. The central part of the fault system shows the highest slip rate. On the contrary, the slip rate at the tips of fault system show a small value compared with the slip rate in the central part of the fault system. Both the height distribution of the terraces and that of the Kongo-katsuragi range, extending to the southwestern part of the Nara basin, have same trend in comparison with the distribution of slip rate along the Kongo fault system.In conclusion, tectonic movement with faulting of the Kongo fault system has affected the formation of landforms in the southwestern margin of the Nara basin.

Early and Middle Pleistocene of North America

<p>River terrace deposits are excellent archives of paleoenvironmental conditions. For this reason, they have been broadly studied, especially the ones dating from the Late Pleistocene and Holocene. On the other hand, little is known about Early Pleistocene terraces due to their state of preservation, which is often not as good as younger terraces, and also due to complications in acquiring good age-dates. The Lower Meuse river, a major tributary of the Rhine river, located in the Southern Netherlands and the adjoining area in northeastern Belgium, exhibits a well preserved terrace staircase which, for decades, has been intensely investigated. The spatial configuration of the terraces is well known, and age constraints, mainly based on correlations made with paleo-climate data from the ODP 677, are also available, which allows for tracing the boundaries of the Early, Middle and Late Pleistocene terraces.</p><p>The existing spatial and temporal constraints of these terraces make the Lower Meuse river terrace staircase a suitable object of study for understanding the effects of the Mid-Pleistocene Transition (MPT; 1.2 – 0.8 Ma) in northwest European river systems. In order to achieve that, we aim to compare the different terrace levels according to their ages, and main sedimentary and morphological parameters. More specifically, a comparison will be drawn between pre-, syn and post-MPT terraces. Differences in sedimentary parameters and trends are expected as a result of the climatic deterioration and changes in the duration of climatic events amid the MPT, as well as due to local tectonics (uplift of the Ardennes region). By comparing pre-, syn- and post-MPT terraces, as examples, we expect to find evidences pointing to an acceleration of incision and erosion rates, decrease of terrace width, and increase in grain-size and gravel-accumulation thickness. The comparative assessment will help to clarify how the Meuse river system responded to the MPT, and to what extent these parameters and trends are a product of climate change and/or tectonic forcing.</p><p>To achieve the proposed goals, this study updates the Meuse terrace maps for the Netherlands and integrates it with maps of the adjacent regions in Germany and Belgium that also encompass remnants of the Meuse terraces. For that, this study relies on existing maps, a high resolution DEM, and a dense borehole database together with sediment core archives provided by the Geological Survey of the Netherlands (TNO). Concomitantly, we are building a new geochronological framework for the terrace staircase based on cosmogenic nuclides extracted from terraces sediment. We are using both burial isochron (three new age-dates) and simple burial dating methods (twelve new age-dates) in order to trace the MPT boundaries stored in the terraces and infer paleo-erosion and paleo-incision rates.</p>

A reappraisal of the Early to Middle Pleistocene Italian Bovidae

Pleistocene tectonics inferred from fluvial terraces of the northern Upper Rhine Graben, Germany

Terrace styles and timing of terrace formation in the Weser and Leine valleys, northern Germany: Response of a fluvial system to climate change and glaciation

The Uranium-trend dating method: Principles and application for southern California marine terrace deposits

From 1985 to 1987, four new localities with abundant fossil mammals were discovered by Cao, Tian and others in the Zhoukoudian (Choukoutien) area, Beijing. They are the East, West, Shangdian and Donglingzi caves. The East Cave fauna consists of 28 speices of mammals and its age is middle Early Pleistocene. The East Cave assemblage shows that a temperature–falling event took place at around 1.20 Ma B.P. at Zhoukoudian. Sixteen species of mammals were collected from the West Cave, which are mainly forms of late Early Pleistocene age. The West Cave fauna represents a transitional fauna from the East Cave fauna (dry–cold) to the fauna (warm) at locality 9. The Shangdian Cave fauna is composed of four forms, being Middle Pleistocene in age. The Donglingzi Cave fauna contains 21 Late Pleistocene forms. In the cave two fossil horizons may be distinguished. The age of the lower horizon is early Late Pleistocene, which is equivalent to that of the New Cave fauna; while the fauna of the upper horizon may be correlated with the Upper Cave fauna.

Geomorphology and tectonics of uplifted coasts: New chronostratigraphical constraints for the Quaternary evolution of Tyrrhenian North Calabria (southern Italy)

Early and Middle Pleistocene landscapes of eastern England

Ecological transitions — But for whom? A perspective from the Pleistocene