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Schumann et al. (2016) presented a field assessment of late Pleistocene to Holocene fluvial sediments preserved in the valleys of Santa Rosa Island, California. This is a rigorous study, based on stratigraphic descriptions of 54 sections and numerous radiocarbon ages. The paper makes important contributions that we would like to highlight, but other parts of the paper rely upon overly simplistic interpretations that lead to misleading conclusions. In one case, a conclusion of the Schumann et al. paper has important management implications for Santa Rosa Island and similar locations, compelling us to discuss and qualify this conclusion.

In tectonically active areas, such as in the northwest Peloponnese of western Greece, geomorphic processes are strongly influenced by active faulting; in many cases such faults cannot be easily identified. In this paper we apply multidisciplinary analysis (morphotectonic indices, neotectonic mapping, geophysical surveys and remote sensing techniques) to map the recently-recognized east–west trending Pineios River normal fault zone with a high degree of accuracy, and to better understand its contribution to the evolution of the ancient region of Elis during Holocene time. Fault activity seems to be related to frequent changes in river flow patterns and to displacements of the nearby shoreline. We argue that fault activity is the main reason for migration of Pineios river mouth as documented for several time periods during historical time. Quantitative constraints on deformation caused by the faulting were applied through the application of the morphotectonic indices proposed in this paper, including drainage network asymmetry and sinuosity, and mountain front sinuosity, all of which indicate that this is a highly active structure. Slip rates calculated to be as high as 0.48 mm/yr for the last 209 ka (based on previously published dating) were verified by applied geophysical methods. The fault surface discontinuity was identified at depth using vertical electrical resistivity measurements and depositional layers of different resistivity were found to be clearly offset. Displacement increases toward the west, reaching an observed maximum of 110 m. The most spectacular landform alteration due to surface deformation is the north–south migration of the river estuary into completely different open sea areas during the late Quaternary, mainly during the Holocene. The sediment transport path has been altered several times due to these changes in river geometry with and the most recent seeming to have occurred almost 2000 years ago. The river estuary migrated to its contemporary position along the southern coast, settled on the hanging wall, inducing retrograding of the northern coast, and settled on the foot wall, with rates reaching the order of 0.52 m/yr, as concluded from historical and recently-acquired remote sensing data.

This paper presents geomorphic, soils and palaeoecological data from a small sub-catchment in the English Midlands in an attempt to provide an integrated picture of Holocene landscape change. The area used has also been the focus of a multi-disciplinary and long-term archaeological survey (Raunds Area Project) and so has a wealth of archaeological and historical data which can be related to the environmental record. The paper combines these data, much of which are only published in the archaeological literature with new interpretations based upon unpublished data and new data particularly from the hillslopes and new radiocarbon dating from the valley floor. It is inferred that despite a long history of pastoral and arable agriculture (since the Neolithic/Bronze Age), colluviation on lower slopes, significant soil redistribution and overbank alluviation only began to a measurable extent in the Late Saxon–Medieval period (9th Century AD onwards). It is suggested that this is due to a combination of land-use factors, principally the laying out of an intensive open field system and the establishment of villages combined with a period of extremes in climate well known throughout Europe. Indeed the critical element appears to have been the social changes in this period that created this regionally distinctive landscape which happened to have a high spatial connectivity and facilitated intensive arable production with high tillage rates. Intense rainfall events during this period could therefore detach and mobilize high volumes of soil and the open field system facilitated transport to slope bases and valley floors. The need for detailed and spatially precise land-use data in order to interpret accelerated landscape change is stressed.

This special issue presents a collection of papers that address a wide range of important challenges and exciting advances in the field of glacial landscape evolution. Primarily, these papers reflect persistent uncertainty that surrounds the mechanisms and timescales of glacial landscape evolution. For example, estimates of the duration of glacial occupancy required for the evolution of characteristic glacial valley forms from previously fluvial landscapes range from 100 kyrs for landscapes beneath large ice sheets (Jamieson et al.) to ~ 400–600 kyrs for glaciated alpine terrains (Brook et al.). Further, the mechanisms of glacial erosion are debated through analyses of the importance of ice thickness (Brocklehurst et al.; van der Beek and Bourbon), ice surface steepness (Vieira) and, in the case of large ice sheets, the co-evolution of ice sheet thermal regime, dynamics, and subglacial topography (Kleman et al.; Swift et al.). Debate concerning the potential climatic impacts of landscape evolution in alpine terrains is represented by van der Beek and Bourbon, who infer a significant increase in relief as a direct result of glacial erosion, and by Brocklehurst et al. and Heimsath and McGlynn, who demonstrate respectively that glacial relief production can be surprisingly modest and that rates of glacial erosion may be lower than those for fluvial incision. Further confirmation that valleys beneath large ice sheets evolve through selective linear erosion comes from studies that have combined geomorphological evidence with cosmogenic nuclide (Briner et al.) and apatite (U–Th)/He thermochronometry (Swift et al.), and the resulting style of landscape evolution is demonstrated by the antiquity of fjords in East Greenland (Swift et al.) and of deep erosion zones and thick drift covered zones in Fennoscandia (Kleman et al.), although the location of areal scouring zones may be subject to major alteration during single glacial events (Kleman et al.). Another set of papers shows that analyses of glacial lineation systems continue to provide important data on the dynamics of glacial landscape evolution, whether the lineations are formed underneath ice streams (Bradwell et al.; Andreassen et al.) or not (Jansson and Glasser), and whether they indicate intricate patterns of landscape modification (Andreassen et al.) or preservation (Jansson and Glasser). The final three papers address rarely-reported issues relating to landscapes of glacial deposition, including moraine degradation (Putkonen et al.), proglacial hydrogeology (Robinson et al.), and the evolution of hummocky-till topography (Clayton et al.).

Analysis of a number of drill cores, geomorphic patterns, and radiocarbon assays on mollusk shells from La Algaida spit, in the estuary of the Guadalquivir River (SW Spain), has revealed the genesis and evolution of a sandy barrier located in a rather complex neo-tectonic setting: the geological boundary between the Alpine belt of the Baetic mountain ranges and the Hercynian massif. The development of this sandy barrier during the Late Holocene has been conditioned by the presence, on the eastern bank of the estuary, of a Plio-Pleistocene paleo-relief which forms part of a raised block in a set of reverse-fault systems with SW-NE alignment, the most conspicuous of which is that of the Lower Guadalquivir Fault (LFG). These systems have influenced the morpho-stratigraphic and geomorphological disposition of the Holocene sediments on both sides of the tectonic alignment. The evidence presented here indicates that La Algaida spit is part of this raised tectonic block. As signs of subsidence are negligible, the spit exhibits series of exposed progradation units which started to develop shortly after the spit itself emerged, in the form of a barrier island. By contrast, subsidence processes affecting the Doñana spit, on the western bank of the estuary, are clearly marked, as they were sustained and massive. This asymmetry explains the relatively meager thickness, 22 to 24 m, of the sedimentary formations constituting La Algaida. Deposits at this location began to accumulate in about 6000–5500 cal. BP, originally as part of extensive shoals lying on top of the Plio-Pleistocene paleo-relief. At present, the spit exhibits three exposed progradation units (PS). Punctuated by erosive discontinuities, these units, or phases, succeeded one another until the Roman period (PS1 and PS2); thereafter, a tombolo formed to connect the erstwhile barrier island with the mainland (PS3). The peculiar, tectonically conditioned, active asymmetry single bondgeomorphological as well as sedimentarysingle bond in the Guadalquivir estuary and its environs contradicts received geological understandings of the area, yet helps understand comparable transformations in other coastal areas of the planet., The investigation has been made possible by the financial support of the Regional Government of Andalusia (Junta de Andalucía) to Research Group RNM276, as well as by funding from the company E2IN2 and entrepreneurs Valentín de Torres Solanot and Manuel Cuevas. The present paper is a product of Phase III of the Hinojos Project as well as a contribution of Project IGCP 639, “Sea Level Change from Minutes to Millennia.”.

This review paper aims at discussing aspects and concepts of the significance of the spatial and temporal distribution of permafrost on glacial and gravitational processes in southern Norway. The study first reviews the distribution of mountain permafrost in southern Norway in comparison with high-relief alpine areas like the Alps, and then discusses the influence of permafrost on gravitational and glacial–geomorphological processes. The basis for the paper is a regional-scale distribution model of mountain permafrost in southern Norway, which is analysed in relation to topographic variations within the same area. The model allows a crude extrapolation to past and future permafrost distribution, which is discussed in relation to geomorphic processes.

The fluvial environment of the central Po Plain, the largest plain in Italy, is discussed in this paper. Bounded by the mountain chains of the Alps and the Apennines, this plain is a link between the Mediterranean environment and the cultural and continental influences of both western and eastern Europe. In the past decades, economic development has been responsible for many changes in the fluvial environment of the area. This paper discusses the changes in fluvial dynamics that started from Late Pleistocene and Early Holocene due to distinct climatic changes. The discussion is based on geomorphological, pedological, and archaeological evidences and radiocarbon dating. In the northern foothills, Late Pleistocene palaeochannels indicate several cases of underfit streams among the northern tributaries of the River Po. On the other hand, on the southern side of the Po Plain, no geomorphological evidence of similar discharge reduction has been found. Here, stratigraphic sections, together with archaeological remains buried under the fluvial deposits, show a reduction in the size of fluvial sediments after the 10th millennium BC. During the Holocene, fluvial sedimentation became finer, and was characterised by minor fluctuations in the rate of deposition, probably related to short and less intense climatic fluctuations. Given the high rate of population growth and the development of human activities since the Neolithic Age, human influence on fluvial dynamics, especially since the Roman Age, prevailed over other factors (i.e., climate, tectonics, vegetation, etc.). During the Holocene, the most important changes in the Po Plain were not modifications in water discharge but in sediment. From the 1st to 3rd Century AD, land grants to war veterans caused almost complete deforestation, generalised soil erosion, and maximum progradation of the River Po delta. At present, land abandonment in the mountainous region has led to reafforestation. Artificial channel control in the mountain sector of the basins and in-channel gravel extraction (now illegal but very intense in the 1960s and 1970s) are causing erosion along the rivers and along large sectors of the Adriatic coast. These changes are comparable with those occurring in basins of other Mediterranean rivers.

Many lowland rivers in the United Kingdom, including the Nene, Soar and Severn, have layered floodplains with a basal gravel of Pleistocene or Late glacial age and a structureless silty clay superficial unit burying the entire former floodplain. This burial is illustrated by the existence of variable, mixed and pedologically disturbed sediments and palaeo landsurfaces between the basal gravels and superficial silty clay. This paper presents a comparison of the pre- and post-late Holocene palaeo landsurfaces and palaeochannels using data from the Nene, Soar and Severn valleys. From this comparison it is argued that during the mid to late Holocene (ca 4500 yr BP to 2500 yr BP) floodplains and river channels underwent a metamorphosis. This is indicated by accelerated vertical accretion, a reduction in floodplain relative relief, changed floodplain soil conditions, a reduction in channel W/D ratios and a resultant increase in the silty clay proportion of channel perimeter sediments. There are indications that hydrological change preceded this metamorphosis but the primary cause was an increase in fine sediment supply during the later Holocene and a disequilibrium between channel bed and floodplain aggradation rates resulting in relative incision. This metamorphosis, which is explained in this paper by the proposed stable-bed aggrading-banks model (SBAB), is the key factor in the Holocene evolution of low-energy floodplain systems in the United Kingdom, upon which more subtle short-term fluctuations are superimposed.

This study presents a multidisciplinary approach to the tectonic geomorphology and history of the Palomares strike-slip fault in the Eastern Betic Cordillera (SE Spain). Analysis combines geomorphological mapping of fan-surfaces, pedological studies of faulted sedimentary successions, geoelectrical prospection and typical paleoseismological routines of structural analyses. Combined application of these methods together with the existing geochronological databases offer probable paleoclimatic and paleoseismic scenarios for the zone from Middle Pleistocene to Holocene. This study segments the Palomares Fault (PLF) in three overlapping “en echelon” N–S trends (PLF1, PLF2, PLF3). The older PLF1 controls the main faulted Almenara-Almagro range fronts. The younger PLF2 cuts and beheads crusted fan surfaces in the Aljibejo zone (ABJ). The intermediate PLF3 controls the development of intervening tectonic reliefs and offset paleosol sequences in alluvial-colluvial deposits. Our analysis focuses on the PLF3 at the La Escarihuela site (ESCH), where outcrops display eight faulted paleosols developed on overlapped Middle Pleistocene colluvial-alluvial deposits, with variable vertical slip of between 21 and 12 cm (bulk accumulated offset: 33 cm), evidence of two surface faulting events. After the structural analysis of the fault planes (striae plunges) net left-lateral displacements of 120.9 ± 3.3 cm (Event 1) to 69.1 ± 5.2 cm (Event 2), associated with maximum magnitudes of c. 6.7–6.5 Mw. However, the faulted sequence is sealed by a thick mature calcrete horizon of similar characteristics to that faulted at the ABJ1 site. Regional chronological data on calcic soils and calcretes in SE Spain assign this mature calcrete to Oxygen isotopic stages (OIS) 9 (c. 300 ka). With this age fixed at the uppermost of the faulted paleosol sequence at the ESCH site (PLF3), soil development features (clay and carbonate contents, thickness, reddishness, etc.) were used as paleoclimatic proxies to correlate soil horizons with conventional OIS. Correlation indicates that clayey Bt soil horizons primarily occurred during warm isotopic stages followed by recalcification and carbonate accumulation (Btk; Bk; Ck horizons) during latter warmer stages. A proposed theoretical geochronological framework suggests that the sedimentary sequence at the ESCH site (PLF3) was deposited between OIS 18 and 9. Major environmental change towards the present semi-arid climate occurred during OIS 13 (c. 500 ka). During this same stage, paleoseismic event 1 also occurred, but paleoseismic event 2 took probably place during OIS 10 (c. 350 ka), before development of the uppermost calcrete sealing the deformation in this fault segment. However, this OIS 9 calcrete is faulted in the ABJ1 and a younger less developed calcrete is faulted in ABJ2 on the PLF2 segment. Chronology proposed in this paper suggests theoretical ages for these events of between OIS 8-OIS 5 for ABJ1 (c. 200 ka) and between OIS 4 -OIS 2 for ABJ2 (c. 40 ka). This last paleoseismic event triggered major landscape changes with still-visible fault scarps, linear tectonic reliefs, alluvial fan beheading and active drainage shuttering. This present work illustrates the use of soil/paleosol analyses in paleoseismology as a useful tool to build paleoclimatic analogues and develop relative chronological frameworks from existing regional age data.

The Tibetan plateau is prone to destructive earthquakes. A number of strong thrust events occurred in the recent past, seeming to migrate from south to north, to the Qilian Mountains area. Many active thrust faults are known in the Qilian Mountains, and most of them are capable of producing large earthquakes. Here we study the southern Zongwulong Shan (shan means mountain) fault that lacks any paleoseismology studies so far. This fault is the eastern boundary of the Qaidam and Qilian blocks, posing a threat to the populated area of Delingha in western China. In this paper, we document its Holocene rupture history based on paleoseismic trenches, and we assess the seismic risk in this area. We excavated two trenches across 4.5 ± 0.5 m high fault scarps in alluvial fans. We found ruptures that affect young alluvial units and almost penetrate the top thick loess unit. We show that four paleoearthquakes occurred in the Holocene with an average recurrence interval of 2300 ± 500 years. The most recent event happened between 272 BCE and 572 CE. Three older events probably occurred in the past 9.5 ± 0.8 ka.

One of the most powerful eruptions of the Holocene, known as the Samalas eruption, had a VEI of 7 and took place on Lombok, eastern Indonesia in 1257 CE. Thick tephra fall covered the entire island, and pyroclastic density currents (PDCs) up to 50 m thick buried almost half of Lombok. Until now, there has been no detailed study of the geomorphological evolution of Lombok related to this eruption, especially for the eastern part of Lombok. The main goal of this paper is therefore to reconstruct the paleo-topography on the eastern part of Lombok before the eruption of the Samalas volcano in 1257 CE, and to analyse the subsequent landscape evolution following this eruption. Data were collected from more than 1300 points in order to gather geomorphological, geological, and geochemical information for the eastern part of Lombok over the last millennium. Data were obtained from wells (which are widespread in the studied area), natural outcrops (mainly cliffs along the shoreline and the rivers), and human-made outcrops in quarries, as well as from the two-dimensional resistivity profiling (Dipole-dipole array) carried out on eastern Lombok in 2016 and 2017. We estimate that 4435 ± 5.5 × 106 m3 of pumice-rich PDC, over a surface of 171 km2, buried the eastern part of Lombok in the aftermath of the 1257 CE eruption, and as a result of this rapid pumice-rich PDC deposition there has been some aggradation of the shoreline at some points, resulting in most of the pre-1257 coral reef being buried. After several intense rainfall events, the deposited volcanic material was probably eroded during the first decades following the 1257 CE eruption by mountain streams, producing lahars. We estimate that the remaining volume of pumice-rich PDC deposits following this erosion is 625 ± 5.5 × 106 m3 over a surface of 89 km2, which is equivalent to 14% of the initial volume.

This paper reports the first reconstruction of storm-generated late Holocene and historical river floods in the North Island of New Zealand. The sedimentary infills of nine palaeochannels were studied in the lower alluvial reaches of the Manawatu River. Floods in these palaeochannels were recorded as a series of sand-rich units set within finer-grained fills. Flood chronologies were constrained using a combination of radiocarbon dating, documentary sources, geochemical markers, and palynological information. Flood units were sedimentologically and geochemically characterised using high resolution ITRAX™ X-Ray Fluorescence (XRF) core scanning and laser diffraction grain-size analysis. The longest palaeoflood record extends back ca.3000 years. The temporal resolution and length of the Manawatu record reflects accommodation space for fluvial deposits, channel dynamics and mobility, and high sediment supply. Floods that occurred in the Manawatu during the mid-1800s at the time of European land clearance and in the first decade of the twentieth century appear to be among the largest recorded in the last 3000 years.

Coastal morphodynamics and environmental changes have been obviously altered by global warming, sea-level fluctuations, and human activities. Palynological analysis is one of the most important tools for providing information on vegetation, climate, and environmental change, which can be relatively sensitive indicators of human activity during the Holocene. However, Holocene coastal morphodynamics and palynological evidence from the Pearl River Delta and coastal areas has not been sufficiently studied. In this paper, we carry out analyses using detailed grain-size and palynological records of pollen, spores, freshwater algae, and marine dinoflagellate cysts from Borehole QZK13 in the Pearl River Estuary (PRE), southern China. The results show information relating coastal morphodynamics, vegetation evolution, climate changes, and anthropogenic activities during the Holocene based on radiocarbon chronology. In general, the PRE experienced marine transgressive processes; sea-level and the coastline tended to migrate landward between 10,700 and 4250 cal yr BP. Meanwhile, abundant arboreal pollen (mainly Castanopsis, Quercus-evergreen, Oleaceae, and Castanea) and small amounts of non-arboreal pollen (mainly Poaceae, Cyperaceae, and Artemisia) were observed in Borehole QZK13, which suggests that subtropical evergreen broadleaved forests were distributed throughout the PRE and adjacent areas, and relatively warm and moist climatic conditions were present during the early-middle Holocene. After that, there were relatively cool and wet climatic conditions, and marine regressive processes occurred in the PRE during the Late Holocene (ca. 4250–960 cal yr BP) indicated by an abrupt increase in aquatic herbs and Dicranopteris. Moreover, we hypothesize that the Neolithic “cultural fault” in the PRE is likely related to frequent storm surges induced by extreme typhoon events that occurred ca. 3000–2700 yr BP.

Closed depressions (CDs) are typical geomorphological features of the loess belt in Europe. CDs have been reported in several regions of the European loess belt, where they are described as hollows, mardeles, wymoki, crovuri, bludtsa and zapadiny. The natural and anthropogenic origins of CDs are debated in literature. Moreover, no comprehensive review of the geomorphic properties or the evolution of these depressions exists. Therefore this paper reviews the characteristics of CDs in the European loess belt and attempts to better understand their genesis based on detailed case studies. The main morphometric features as well as sediment deposits within CDs in several sub-regions of Europe were analysed and compared. Morphometric properties of CDs from the West European and East European loess belt were investigated through a comparison of CDs from two representative regions, i.e. East Poland and Central Belgium. In both study areas, CDs under cropland are similar. However, a comparison of morphological features of CDs under forest, revealed clear differences, suggesting a different origin of CDs from both regions. Infilled sediments in CDs show various litho-genetical features in different regions of the European loess belt. The morphometric features, ages and stratigraphy of infillings clearly indicate that both anthropogenic and natural processes have shaped these landforms within the loess belt of Europe. CDs observed in Eastern Europe may have a very different origin than those documented in Western Europe. Detailed analysis of CDs in Poland and in neighbouring regions of East Europe, suggest that CDs are natural landforms: thermokarst, deflation and dissolution of loess are reported as probable genetic processes. In contrast, several studies in Western Europe indicate a dominant anthropogenic origin (i.e. digging of calcareous loess or marls, bomb and mining craters, collapse of underground limestone quarries), although CDs formed by natural processes (i.e. piping, dissolution of limestone and salt lenses below the loess cover) are reported as well. CDs act as important archives, allowing one to reconstruct both natural and anthropogenic processes operating in the past. As CDs store most sediments eroded within their catchment they provide ideal sediment traps to assess long-term erosion rates in these environments which have hitherto been under-researched. More research is needed to unravel the genesis and evolution of these depressions to better understand the importance of the Late Glacial and Holocene stages for the morphogenesis of the loess belt in Europe.

The geomorphological development of Holocene coastal plains around the world has been studied since the beginning of the twentieth century from various disciplines, resulting in large amounts of data. However, the overwhelming quantities and heterogeneous nature of this data have caused the divided knowledge to remain inconsistent and fragmented. To keep improving the understanding of coastal plain geomorphology and geology, cataloguing of data and integration of knowledge are essential. In this paper we present a GIS that incorporates the accumulated data of the Netherlands’ coastal plain and functions as a storage and integration tool for coastal plain mapped data. The GIS stores redigitised architectural elements (beach barriers, tidal channels, intertidal flats, supratidal flats, and coastal fresh water peat) from earlier mappings in separate map layers. A coupled catalogue-style database stores the dating information of these elements, besides references to source studies and annotations regarding changed insights. Using scripts, the system automatically establishes palaeogeographical maps for any chosen moment, combining the above mapping and dating information. In our approach, we strip the information to architectural element level, and we separate mapping from dating information, serving the automatic generation of time slice maps. It enables a workflow in which the maker can iteratively regenerate maps, which speeds up fine-tuning and thus the quality of palaeogeographical reconstruction. The GIS currently covers the late Holocene coastal plain development of the Netherlands. This period witnessed widespread renewed flooding along the southern North Sea coast, coinciding with large-scale reclamation and human occupation. Our GIS method is generic and can be expanded and adapted to allow faster integrated processing of growing amounts of data for many coastal areas and other large urbanising lowlands around the world. It allows maintaining actual data overview and facilitates new ways of analysis at national, regional, and local scales. © 2016 Elsevier B.V.

The Rift of Corinth is a world-class example of young active rifting and, as such, is an ideal natural laboratory of continental extension. However, though much investigated for two decades, several aspects of the mechanisms at work are still poorly understood. The aim of this paper is a detailed morphometric study of the fluvial landscape response to the tectonic uplift of the rift southern shoulder in order to reconstruct the rift's Quaternary evolution, with special attention to timing, location, and intensity of uplift episodes. Based on the use of a large set of catchment and long profile metrics complemented by the new R/SR integrative approach of the regional drainage network, we identified three distinct episodes of uplift of the northern Peloponnese coastal tract, of which the intermediate one, dated around 0.35–0.4 Ma, is only recorded in the topography of the central part of the rift shoulder, and the youngest one appears to have propagated from east to west over the last 10–20 ka. While net uplift remained minimum in the eastern part of the study area during the whole Quaternary, it shows a clear maximum in the central part of the rift shoulder since 0.4 Ma and an eastward shift of this maximum in recent times. Maximum uplift rates calculated from the morphometric data are of > 1.05 and 2–5 mm year− 1 for, the mid-Middle Pleistocene and Holocene uplift episodes, respectively. The morphometric evidence reveals an onshore uplift history remarkably consistent with the rift evolution reconstructed from other data sets. In the long term, it shows a stable pattern of maximum activity in the central part of the rift, confirming previous conclusions about the absence of rift propagation. In the short term, it sheds light on a possible E–W migration of the zone of recent uplift, suggesting that in the near future fault activity and seismic hazard might concentrate in the Heliki–Aegion area, at the western tip of this uplift wave.

This paper describes dune sand-paleosol-sequences of four pits in Northern Fuerteventura (Canary Islands). The elaborated stratigraphy is reinforced with luminescence dating to provide a first chronological estimation. Apart from a Holocene colluvial layer, the sequence spans the period from ca. 50 ka to ca. 280 ka. Paleosols were formed during glacial times and point to a standstill in sand supply. The isotopic composition of terrestrial gastropod shells retrieved from soil horizons reflects fluctuations in humidity conditions during different edaphic phases. Because eolian sands were deposited during glacial times as well, it is inferred that soil development was simply caused by a decrease in sand supply independent of climate change. Our geomorphic, geochronological and isotopic results are discussed considering different perspectives of dune sand-paleosol intercalation and more broadly, soil-forming conditions in general.

This paper presents a new and simple recursion model to calculate the erosion rates of flights of narrow, late Holocene terraces under conditions of regular uplift. The general equations developed are: Δ x n = Δ x ′ n + Δ x n − 1 − Δ z n − 1 / tan θ n − 1 , and e n = Δ x n / ( t n − t n + 1 ), where n is the number of narrow terraces, Δ x n is the original width of narrow terrace n , Δ x ′ n is the observed width of narrow terrace n , Δ x n − 1 is the original width of narrow terrace n – 1 (one step below terrace n ), Δ z is the height of the narrow terrace, θ is the gradient of the slope, and e is the backwearing (i.e., horizontal erosion) rate. The model can be used to calculate the backwearing rate if the widths of the present shore platform and of the emerged narrow terraces can be obtained, and where chronological control is available. Backwearing rates on the Ashizuri, Boso and Kii peninsulas in Japan were calculated using the model to be approximately 0.001, 0.2–1.0, and 0.009 m/yr, respectively. These calculated values are in agreement with the rates of backwearing directly measured in previous studies.

This paper focuses on two objectives: (i) the presentation of the methodology for using small-sized iron slag (called microslag) as a stratigraphic marker to reconstruct the centennial-scale floodplain evolution and (ii) the study of the geomorphic evolution of the Ardennian rivers situated in the Lienne catchment (southern Belgium) by means of microslag evaluation, 14C dating, topographic surveys and sedimentological analysis. Using these data, the floodplain history since the Late Pleistocene is reconstructed, fine floodplain sedimentation and lateral mobility rates are estimated, and channel incision phases are identified. The first Holocene erosion episode occurred during the Bronze Age. Archaeological data and historical sources indicate Roman and High Middle Age occupations in the area but no evidence of erosion or increased floodplain sedimentation have been observed. Several peat layers have been dated in the Chavanne floodplain to approximately 1000 BP and probably indicate very low anthropogenic activity and a high level of groundwater. Before 1000 CE, the fluvial style of the Ardennian rivers was probably different, characterized by a low-level forested floodplain, which explains the presence of frequent peat layers within the alluvial sequences and abandoned channels. From the eleventh century onwards, a generalized increase in sedimentation rates occurred, coinciding with a higher concentration of charcoal in the alluvium and also the formation of colluvial deposits. Analyses of slag concentrations allowed us to reconstruct the evolution of the floodplain topography. In the Lienne catchment, the mean floodplain aggradation over the last several centuries is between 2.7 and 16 cm/century, depending on the study site. Such differences in floodplain sedimentation rates can be explained by several factors such as the distance to past cultivation areas, the degree of woodland clearance, flow velocities during floods and the incision of the riverbed during recent centuries, which reduces the frequency of inundation and, therefore, sedimentation on floodplains.

Marine tidal notches are developed by bioerosion in the intertidal zones of rocky coasts, but a combination of sea-level change and crustal movements can result in them being raised above or submerged below the water line. For that reason, the present-day elevation of these former shorelines relative to the mean sea level has long been used to quantify relative coastal uplift and subsidence in tectonically active areas, assuming that the sea-level (eustatic) change component is known. Along the microtidal Mediterranean littoral, it is generally assumed that notches develop during relative stillstands of sea level, when tectonic and eustatic trends are in unison, and that discrete notch levels record abrupt shoreline changes caused by local seismic displacements. Recently, however, a climatic model for notch formation has been proposed, in which stable periods of Holocene climate favour enhanced erosion; in this competing model, the rate of sea-level rise is lower than the tectonic uplift rate and individual notches are not specific seismic indicators. Because marine notches are widely used as geomorphic markers of tectonic, and in some cases palaeoseismic, movements, a reappraisal of the geological significance of these strandlines is warranted. In this paper, we explore the two conflicting notch models using a database of Eastern Mediterranean palaeoshorelines. Although we conclude that the spatial and temporal distribution of the notches supports a dominantly tectonic control on notch genesis as a result of earthquake clustering, we highlight how the diachronous timing of notch development tempers their value as tectonic markers.

This paper focuses on simulations of the morphological evolution of an estuary during sedimentary infilling that accompanied Holocene sea-level rise. The simulations were conducted using the Estuarine Sedimentation Model, which uses a behaviour-oriented approach, supported by the chronostratigraphy of the estuary's sedimentary sequence. Behaviour curves were computed to represent the relationship between the estuarine channel depth below maximum high tide and the net accretion at a given location relative to the average sedimentation rate of the estuary during the Holocene. The model was validated by comparing the observed present-day bathymetry of the Guadiana River Estuary, southeastern Portugal, with the corresponding simulated bathymetries for nine control sections across the estuary. The best fit between simulated and actual sediment surface elevations was obtained along the cross-sections in the sheltered, low-energy environments of the estuary. The accuracy of the sedimentary stratigraphy of the best-fit model was further established using 16 radiocarbon ages obtained from five boreholes in the estuary. The present approach is particularly suitable for simulating long-term morphological evolution in sheltered estuarine environments where tidally driven vertical aggradation dominates at centennial to millennium timescales. However, the accuracy of simulated sediment surface elevations and consequently the robustness of behaviour-type models based on Geographical Information System platforms can be enhanced by incorporating (i) the impacts of nearshore hydrodynamic processes and episodic flood events in highly energetic channels, and (ii) the impacts of cross-currents in meandering channel sections. (C) 2015 Elsevier B.V. All rights reserved. FCT [SFRH/BD/70747/2010, SFRH/BPD/85335/2012]

by Witold Zuchiewicz and Jerzy Zasadni (2012) intended for this volume YOUNG TECTONICS OF THE OUTER WESTERN CARPATHIANS IN THE LIGHT OF SOME MORPHOMETRIC INDICES In this paper, we test the applicability of some morphometric indices commonly used in tectonic-geomorphological studies to the area of the Outer Western Carpathians representing an Alpine fold-and-thrust belt. This belt was shaped largely in Miocene times and shows traces of Pliocene-Quaternary tectonic activity consisting mainly in some remnant folding and faulting. This is indicated by scarce examples of faulting within Quaternary strata, numerous cases of clast fracturing owing to palaeoearthquakes of relatively large magnitudes, as well as warping and tilting of Pleistocene and Holocene strath terraces. Analysis of selected morphometric indices (valley floor width-valley height ratio, riverbed gradients, stream length-gradient index, basin elongation ratios and others), conducted for the entire region and some chosen test areas in the westernmost part of the Outer Western AC C EP TE D M AN U SC R IP T ACCEPTED MANUSCRIPT 24 Carpathians, proved their usefulness in detecting zones showing tendencies to young surface uplift. However, in the case of the stream length-gradient index (SL, Hack’s index) a word of caution should be added, since the index is extremely sensitive to lithologic contrasts in the bedrock and its applicability to young tectonic analysis of fold-and-thrust belts appears to be strongly limited. Dr Andrzej Piotrowski, apiot@pgi.gov.pl, Szczecinie Panstwowy Instytut Geologiczny, Szczecin, Poland and Dr Klaus Reicherter, RWTH Aachen University, Germany

This paper reviews the sedimentological and geomorphological imprints of prehistoric and historical tsunamis in the four main estuaries of SW Spain. These imprints include beach erosion, filling of intertidal channels, deposition of bioclastic layers, washover fans and reworked aeolian sheets and the breaching of spits and tombolos. Most of these imprints were caused by the 218-209. BC and AD. 1755 tsunamis, although evidence of other tsunamis has been identified. In these two events, effects on human populations were severe and diverse, such as human loss of life, changes in coastal settlements and international borders, damage to port infrastructure or flooding of marsh and inhabited areas. New radiocarbon reservoir data were included in order to obtain an approach to the recurrence period of these high-energy events (700-1000. years) in this area. Gobierno de España CTM2006- 06722/MAR, CGL2006-01412/BTE, CGL2010-15810/BTE, CGL2012- 30875 European Union SEJ-4770 Fundaçao para a Ciência e a Tecnologia PTDC/CTE-GIX/110205/2009

Geomorphological, sedimentological and geochronological analyses have been undertaken to decipher the effects of Quaternary environmental change on the development of the Rio Bergantes, Ebro basin, northeast Spain. Field mapping and profiling using aerial photography and airborne LiDAR data have identified a sequence of six river terraces. Age control, provided by luminescence dating, has revealed two major phases of valley floor aggradation that appear to have occurred at ~ 183–130 ka (Terrace BT1, elevated ~ 25 m above the modern river channel) and ~ 111–26.8 ka (BT2, ~ 18–20 m above the modern river channel), punctuated by ~ 20 m of incision in the intervening period. Following these two phases of large-scale aggradation, the Bergantes river system appears to have adjusted to a relatively sediment-limited regime and responded to environmental changes through a series of smaller cut and fill cycles. This resulted in four lower elevation terraces (BT3–BT6) that are inset within the older (BT1 and BT2) valley fills. These lower terraces have been temporally constrained to ~ 24.5–14.2 ka (BT3); 10.6–9.8 ka (BT4); 8.3–6.2 ka (BT5) and ~ 3 ka (BT6). Field sedimentological and stratigraphic analyses of the alluvial fills indicate the influence of tributary and hill slope derived sediment supply during the aggradation of BT1 and, to a lesser extent BT2. This contrasts with the predominantly trunk river derived deposits which make up the fill of BT3–BT6, when the hillslopes and tributaries in the study area appear to have been relatively de-coupled from the trunk river. Data presented in this paper suggest that the Bergantes river system has responded to, and has preserved, a record of environmental changes operating both in synchrony with, and at a higher frequency than, Milankovitch-driven glacial–interglacial cycles. Major net aggradation phases (those associated with relatively large amounts of fluvial sediment e.g. BT1 and BT2) appear to coincide with Pleistocene glacial conditions in MIS 6, and parts of MIS 5 and MIS 4, when the climate on the Iberian Peninsula was cool and dry. Intervening phases of net valley incision appear to coincide with warmer and moister climates in Pleistocene interglacials. The younger terraces (BT3–BT6) are characterised by much smaller amounts of fluvial sediment supply. Dating control places their development during stadial (aggradation) and interstadial (incision) events of the Late Pleistocene and Holocene. Some phases of aggradation appear to coincide with North Atlantic Heinrich Events, and also with other securely dated phases of aggradation elsewhere in the Mediterranean basin.

The Kamienne Mts. in SW Poland abound in geomorphic evidence for past landslides developed at the rhyolite/sedimentary rock contact, but it remains unknown when the displacements occurred. The slopes generally have been stable in the last 200 years or so, covered by historical records. In this paper we use the presence of periglacial solifluction layers (cover-beds) and soil characteristics as indicators of the status of hillslopes and relative age of landslides. We follow an assumption that if landslides predate the Holocene, then solifluction layers should be present and soils within and outside landslide-affected slopes should have similar characteristics, allowing for differences caused by local factors. Cover-beds are not expected to be associated with Holocene landslides. Differences in the degree of soil development may be used to argue for different ages of some landslides within the Holocene. The absence of solifluction layers cannot always be regarded as the evidence of post-Pleistocene landsliding since such a layer is unlikely to have ever formed on densely jointed, but otherwise strong, rhyolite. Soil morphological properties, particularly horizonation, helped to establish the relative chronology of mass movement and to recognize both early to mid-Holocene and late Holocene landslides. Soils are good relative-dating tools and their usage does not necessarily require adherence to any particular soil classification system. This is because morphological features of entire profiles provide more information than diagnostic properties used in these systems.

Large areas of the Norwegian fjord landscapes are covered by hillslopes that reflect the influence of glacial inheritance from the Last Glacial Maximum (LGM). The focus of this paper is two-fold: (1) analyze the spatio-temporal variability of relevant denudational slope processes and process intensities over the Holocene; and (2) detect Holocene modification of the glacial valley morphometry. Research was performed on hillslope systems within two steep, parabolic-shaped and glacier-fed tributary valleys, Erdalen and Bodalen located on the western side of the Jostedalsbreen ice cap in western Norway. Orthophoto delineation, high resolution mapping (TLS), detailed geomorphological information and spatial data analysis were combined with dating techniques and geophysical investigations. Calculated Holocene rockwall retreat rates at selected slope test sites range from 0.38 to 0.67 mm yr− 1, with a mean value of 0.53 mm yr− 1. Slightly higher values were found in Erdalen, with a mean rockwall retreat rate of 0.57 mm yr− 1 compared to 0.50 mm yr− 1 in Bodalen. Valley-wide Holocene rockwall retreat rates of 0.38–0.50 mm yr− 1 are consistent with other estimates of Holocene rockwall retreat rates in cold mountain environments. It is shown that the glacial inheritance of topography is the most important factor controlling valley development since the LGM and that sediment storage capacity is primarily conditioned by valley morphometry. Compared to contemporary rates, the results indicate enhanced denudation activity and intensity immediately following deglaciation and during the ‘Little Ice Age’. The overall tendency of landscape development is postglacial widening of the parabolic-shaped valley morphometry through rockwall retreat with associated debris accumulation beneath rockwalls. As a result, the glacially sculpted topography has not yet adapted to denudational processes acting under Holocene environmental conditions.

This paper focuses on the influence of the “Little Ice Age” (LIA) glacier advance on hillslope morphometry and development in selected U-shaped and (para)glacial tributary valleys, which are still occupied in their upper parts by outlet glaciers of the Jostedalsbreen ice cap in Western Norway. Especially the morphometric influences and geomorphic consequences of the LIA glacier advance on the development of the valley-side hillslope systems and associated denudative processes are assessed by comparing hillslope systems located inside and outside of the LIA glacier maximum extent. The process-based approach applied includes orthophoto- and topographical map interpretation as well as hillslope profile surveying in field for morphometric analyses and detailed geomorphological mapping for process analyses. In addition GIS and DEM computing as well as geophysical measurements (georadar) for storage analyses are performed. It is found that hillslopes inside the LIA glacier limit have steepened lower hillslope segments due to a negative sediment net balance of removal and deposition of material by the advancing LIA glacier front. There are significant differences in the present-day slope debris thickness and composition between hillslopes inside or outside the LIA glacier limit. Slope debris from hillslopes inside the glacier maximum extent are clearly less thick and display a different internal structure originating from a combination of debris from gravitational processes and reworked modern glacial deposits. Compared to that slope debris covers on hillslopes outside the LIA glacier limit are in general noticeable thicker and less influenced by glacial deposits. The combined effects of modified slope morphometry and altered composition of material covering lower hillslope segments have generated a higher intensity of post-LIA denudative hillslope processes.

This paper presents new field data pertaining to the deglaciation of the Lac Guillaume-Delisle area, aiming to establish its emplacement in time and space between the breaching of the Laurentide Ice Sheet (LIS) over Hudson Bay and the final ice disintegration over Northern Quebec and Labrador. The deglaciation of the east coast of Hudson Bay started at 8200 cal BP in the south-western sector of the Lac Guillaume-Delisle estuary, when the marine limit was at 271 m above sea level (asl). By 8000 cal BP, frontal moraines and proximal glacio-marine sediments were deposited in the transverse valleys along the coastal cuesta ridges at a mean elevation of 250 m asl. They are associated with a regional topographic pinning event of the western margin of the Quebec-Labrador Ice Sheet (QLIS) on the high coastal relief. At that time, the coastal relief encouraged a change in deglaciation mode from fast calving in the open and deep Tyrrell Sea to a tidewater ice-sheet controlled by the topography. The ice front thereafter retreated eastward under very large and fast crustal unloading where ice-contact deltas fed by short sandar and eskers were deposited between 7900 and 7400 cal BP (between 240 and 195 m asl), as the ice front was receding inland and lost contact with Tyrrell Sea. A series of deposits and landforms characterize this modification in the sedimentation regime when the ice-sheet margin changed from tidewater to terrestrial. Dating shows that the deglaciation of the western margin of QLIS on land was very fast, i.e. faster than when the front of the ice-sheet was in contact with the Tyrrell Sea. As the fall of the relative sea-level continued, a large volume of paraglacial sediments was deposited in the river valleys making up vast fluvial terraces and deltas between 6500 and 5800 cal BP (between 125 and 100 m asl). Since then, land emergence has continued at a rate of about 1.3 m/century. Downcutting by rivers, post-glacial deltaic sedimentation and shoreline changes still continue today.

This paper presents the main physical and human-induced stresses that have shaped the recent evolution of the Patia River delta, the largest and best-developed delta on the western margin of South America. During the Holocene, the Patia Delta moved southward and the northern part became an estuarine system characterized by large extensions of mangrove ecosystems. However, a major human-induced water diversion, starting in 1972, diverted the Patia flow to the Sanguianga River, and shifted the active delta plain back to its former Holocene location. This discharge diversion has led to sediment starvation of the southern delta lobe and changed the northern estuarine system into an active delta plain. In addition, coastal areas of the Patia delta subsided as a result of a devastating tsunami in 1979. Morphological changes along the delta coast are evidenced by: (1) coastal retreat along the whole delta front during the period 1986–2001; (2) coastal retreat along the abandoned delta lobe for the period 2001–2008; 56% of the southern delta shoreline is retreating and only 4% of the coast shows signs of accretion; (3) progradation of the northern delta region during the period 2001–2008; the discharge diversion of the Patia River to the Sanquianga has apparently balanced the observed trends in coastal erosion and sea-level rise (5.1 mm yr − 1 for the period 1984–2006, after the 1979 tsunami); (4) formation of transgressive barrier islands with exposed peat soils in the surf zone; and (5) abandonment of former active distributaries in the southern delta plain with associated inlet closure. In the northern delta lobe, major geomorphic changes include: (1) distributary channel accretion by morphological processes such as sedimentation (also in crevasses), overbank flow, increasing width of levees, inter-distributary channel fill, and colonization of pioneer mangrove; (2) freshening conditions in the Sanguianga distributary channel, a hydrologic change that has shifted the upper estuarine region (salinity max /Q min ); (3) spatial switch of delta distributaries related to tectonic movements and subsidence; (4) a relative sea-level rise of 5.1 mm yr − 1 after the occurrence of the 1979 tsunami; (5) episodes of sea-level rise associated with the ENSO cycle; and (6) human-induced discharge diversion. The information presented here is valuable evidence for understanding the role of extreme events versus ‘normal’ conditions in creating and shaping deltas.

Yardangs are typical wind-eroded landforms that are found in most of the world's major deserts. This paper describes the morphology of yardangs in the Kumtagh Desert, analyzes their control factors, and discusses their development processes, age, and rates of formation. Yardangs in the Kumtagh Desert lack the ideal streamlined morphology and the length-to-width ratio close to 4:1 that have been previously described as being due to their unique controlling factors, which include a combination of stratigraphic structures, wind erosion and fluvial erosion. Fluvial erosion plays a particularly important role in the development of the yardangs, though wind continuously sculpts their morphology. The development of yardangs can be divided into four stages: an embryonic stage, adolescence, maturation, and recession. Most yardangs in the Kumtagh Desert are in the mature to receding stages. We determined an approximate age for the yardangs based on the erosion rates estimated by several researchers: on this basis, the yardangs in the Kumtagh Desert appear to have formed during the Holocene.

The upper Das Velhas River basin is located in the central portion of the Quadrilatero Ferrifero in southeastern edge of Sao Francisco Craton, southeastern Brazil. Its drainage network has a strong lithostructural influence and mountainous river segments crossing different tectonic blocks. The neotectonic activity in this cratonic edge is associated with epirogenetic Brazilian Shield uplift and with local and regional differential movements of crustal blocks due to WNW migration of South-American plate. This process cause an intraplate transfer of tectonic efforts, forcing the reactivation of old faults (NW-SE and NE-SW) and the generation of recent ones (E-W). Using optically stimulated luminescence (OSL) dating and fluvial deposit data, this paper focuses on the late Cenozoic evolution of this mountainous river basin, relating it to tectonic and climatic forcing. Even with few records of ancient alluvial deposits as a result of intense dissection, three levels of river terraces were identified in some sites along the valley: a higher terrace level (T3), a cut-in-bedrock terrace of ~ 48 ka; an intermediate terrace level (T2) of ~ 7.5 ka; and a lower terrace level (T1), of ~ 1 ka. The T2 is found along the valley as a cut-in-bedrock terrace or as a fill terrace, and is found T1 as a cut-in-bedrock terrace or as a nested fill terrace or even overlapping T2 sediments. The diverse relation between these terraces may be related to unequal fluvial downcutting. We identified three main downcutting periods: (i) before T3; (ii) from T3 to T2, related to Late Pleistocene regional tectonics; and (iii) from T2 to T1, which was a response to tectonics and climate change in the early Holocene. These stages of more intense downcutting should be a response to uplift pulses. In the most active blocks, cut-in-bedrock terraces show a greater unevenness in relation to lower levels, while in the most stable blocks, T1 is found as a nested fill terrace or overlapping T2.