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The present paper deals with the historical evolution of the northern Bay of Cadiz (SW Spain) between the last eustatic maximum (6.5 ka BP) and the present day, by means of a series of independent proxies. The zone is constituted by the tidal estuary of the Guadalete River, filled with saltmarsh sediments during the late Holocene, due to the sheltering of the zone by a confining outer sandy barrier. The northern border of the Bay records an urban settlement of Phoenician Age (first millennium BC), Dona Blanca. A detailed survey was made in the contact between the Phoenician city and the saltmarshes in order to detect other possible urban structures related to the morphological and sedimentary evolution of this environment during historical times. Two campaigns with GPR Stream-X array were carried out as well as aerial imaging and topographic survey with UAV. In parallel, a total of 8 boreholes were made in different parts of the saltmarshes, including radiocarbon dating of selected samples for estimating sedimentation rates in the saltmarshes. Results obtained by georadar prospection and UAV survey revealed the presence of a second urban settlement on the marginal sedimentary plain, very probably installed upon a sandy fluvial island of the Guadelete River. The urban remains, of Punic Age, are partly covered by clay sediments due to the subsequent evolution of these saltmarshes, where sedimentation rates of up to nearly 2.4 mm/yr have been estimated for environments close to fluvial and/or tidal channels and hence more affected by sediment aggradation during flooding episodes. In recent times, river regulation by dams and the artificial desiccation and cropping of the saltmarshes have interrupted the natural trend of the area towards sedimentary silting up.

This paper discusses successive changes in the evolution of the fluvial system observed throughout the Blądzikowo Formation at the Mrzezino key site in northern Poland. The study focuses on the development of fluvial sedimentation during Marine Isotope Stage 7. The sedimentary record of the Pleistocene at the study site shows a well-developed sequence that is over 30 m thick. The Blądzikowo Formation shows a quick evolution of the fluvial system from a high-energy sandy braided river, to a meandering sandy river and, finally, to a low-energy meandering/anastomosing river with significant suspension settling. This transition is explained as a decrease in flow energy, increase in aggradation ratio and expansion of accommodation space during deposition time. A change in the fluvial system has not been manifested in the variations of the plant cover. Palynological analysis indicates that climate conditions were generally stable, cool and humid (boreal). Sediment transport occurred towards the N-NW, through a valley with a NW-SE axis. Infrared optically stimulated luminescence (IR-OSL) dating shows the sequence formed from 225.6 ± 17.2 to 210.5 ± 16.6 ka. Well preserved fluvial cycles and 35 m of thickness suggest the intensive accumulation of the Blądzikowo Formation with decreasing ratio of lateral erosion. It suggests an increasing influence of base level rise on evolution of fluvial system, mostly during MIS 7.

In this paper, we discriminate the contribution of the different sediment sources into a river situated in the semiarid region of northern Chile, differentiating the ones driven by the paraglacial response from the ones yielded to the tributary-junction alluvial fans or the ones coming from the hillslopes. The sedimentary infilling is accurately described in the main landforms such as alluvial fans, alluvial terraces and landslides in the current valley floor where twenty-six 14C AMS samples were picked up. The 14C age data indicate that the aggradation in the uppermost part of the valley immediately postdates the glacial retreat at ∼15,000 14C years cal. B.P. and spans the whole Holocene starting at 11 ka. B.P. and finishing about 2 ka B.P. The main sources for lateral inputs are debris flows from tributary catchments in the portion where the river is embedded in between 1000 and 2000 m a.s.l as well as catastrophic landslides. Additionally, an extensive detailed geomorphological mapping is provided to discuss the meaning of the ages together with an assessment of where the samples came from. Finally, the dataset and field criteria provided in this work contribute to better perform paleoclimatological interpretations for the semiarid fluvial systems of northern Chile. These interpretations usually consider the increased influence of the westerlies during the Holocene and the span of time that the paraglacial response delivers glacigenic sediments into the system.

The Oscurusciuto rock shelter, located in the ravine of Ginosa (Taranto), is one of the key sites for the study of Neanderthal groups in Southern Italy. The rich stratigraphic sequence of the site, which is ascribable entirely to the Middle Palaeolithic, is rich in anthropic remains and combustion structures, attesting occupation by Neanderthals during MIS 3. This paper is focused on the study of Stratigraphic Unit (SU) 13, made up of a compact sandy sediment mixed with pyroclastic sediment derived from the underlying tephra level (SU 14). The latter has been identified as Monte Epomeo green tuff (dated Ar/Ar 55 ± 2 ka). The first stable human occupation of the shelter after tephra deposition is represented by unit 13. Our aim here is that of separating the Stratigraphic Unit into its main components so as to obtain a high temporal resolution on the activities which took place in this SU, and to reconstruct the individual events which formed the palimpsest. In order to fulfil these objectives, a multidisciplinary approach was needed through which data could be integrated from the microstratigraphy of the hearths; from the technological study of the lithic industries; from the individuation of the Raw Material Units (RMUs); from refitting and co-joining and from spatial analysis (GIS science/tool). The integration of these analytical methods reveals that SU 13 of the Oscurusciuto rock shelter was the product of a series of events ascribable to a short time span. This layer was formed by sediment aggradation and cementation (e.g., brecciation) processes. Human activities contributed to the sediment build up with the introduction of wood ash, lithic raw materials and bones. The results show the importance of using integrated research methods in order to identify short anthropic events within a palimpsest.

In a recent paper Chakrabarti Goswami et al., 2013 discussed the geomorphology of Matiali fan and the terraces formed along the rivers traversing this fan, in the Jalpaiguri District of West Bengal, eastern Himalaya. The area of their study is tectonically active with a couple of blind thrust traversing the Quaternary fan deposits. The authors have proposed that the tectonic movements along blind thrust faults of the area, were the main control of formation and present disposition of the terraces. In proposing this, the authors have completely ignored the question of aggradation of the terraces, sediment:water ratio in the alluvial system and role of well-known climatic fluctuations during the time span over which these geomorphic features formed in eastern Himalaya. They have reported fault propagation folds deforming the fan sediments, but did not document any deformation or any other features within the younger terraces that could substantiate their claim of tectonics as the main agent for the development of the terraces. In this comment we point out the inconsistencies in the tectonogeomorphic model proposed by them and suggest that the climate induced aggradation played a major role in the formation of the terraces in the river valleys in this area.

Archaeobotanical research at the Yuezhuang and Xihe sites of the Houli culture in the Lower Yellow River has found abundant carbonised plant remains, including rice, millet, weed seeds and many other plants (7800–7000 cal BP). Although studies of the diverse economic practices of the Houli people have begun, issues such as ecological diversity and relationships between site formation processes with environmental changes are still poorly understood. Applying soil micromorphology and related methods such as particle size distribution and loss-on-ignition at Yuezhuang, this paper presents results of the geoarchaeological investigation and the implications for the reconstruction of site formation processes in relation to river alluvial history. A long alluvial sequence is reconstructed, consisting of frequent alternations of short-periods surface stabilities and succeeding alluviations. Human occupations corresponded to those short-term surface stabilities and are evidenced by the presence of anthropogenic inclusions in thin sections, including burned bone fragments and pottery sherds. The significances of this study to an ecological approach focusing on environmental changes and cultural adaption are discussed.

The sequence of terraces of the River Thames in southeast England has previously been shown to span the period from the earliest Pleistocene to the present. This terrace sequence contains biostratigraphical and sedimentary evidence that testifies to the high-amplitude climatic changes of the Quaternary. Large-scale fluvial incision, resulting in basin-wide terrace formation, appears to have been concentrated at the warming limbs of the major climatic glacial–interglacial cycles, when sediment supply was greatly reduced. This incision and subsequent valley-floor widening created the accommodation space for the later aggradation of the terrace sediments during the following warm–cold transitions and during the cold stages, when high-sediment supply conditions prevailed. Although the timing of terrace aggradation may be controlled by climate change, the progressive valley incision recorded by terrace staircases cannot easily be explained in terms of Quaternary climatic change alone and recently developed models suggest that long-term incision by the Thames has been driven by uplift. This paper presents an overview of the available terrace data and tabulates incision amounts and rates between key stratigraphic horizons. Superimposed upon these broad changes, revealed by the complex internal sedimentary architecture of many terrace sediments, are the geomorphological system responses to both higher-frequency climate-driven changes and more localized intrinsic fluvial system adjustments.