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El Olivo Cave (Pruvia de Arriba, Llanera, Asturias, Spain) is a small karst cave located in the Aboño River basin and formed in the Cretaceous limestone of the Mesozoic cover of the Cantabrian Mountains (north of the Iberian Peninsula). It contains an important upper Pleistocene sedimentary, archaeological, and paleontological record, with abundant technological evidence and faunal remains. The archaeological record shows a first occupation that could correspond to the Middle Paleolithic and a second occupation in the Middle Magdalenian. The stratigraphic sequence inside and outside the cave was studied with geoarchaeological methodology. In this paper, the lithostratigraphic sequence is analyzed, and the data from the granulometric, mineralogical, edaphological, and radiometric analyses are presented. The results of these analyses enable an accurate interpretation of both the lithostratigraphy of the deposit and the processes responsible for its formation and subsequent evolution. The available numerical dates allow us to locate the first sedimentation episode in the cave in OIS 7a, in the Middle Pleistocene, the base of the outer fluvial sedimentation in the cold OIS 3a stage of the Upper Pleistocene and the Magdalenian occupation in the Last Glacial Maximum (OIS 2) at the end of the Late Pleistocene. [ABSTRACT FROM AUTHOR]

Most studies on the geomorphological evolution of the Holocene from the Ebro depression (NE Spain) are focused on the period up to the Roman Epoch (218 BC–476 AD) while some references to medieval (476 AD–15th century) deposits are also occasionally dated. This paper focuses on the establishment of aggradation units on the valley bottoms and slopes of the Ebro depression after 1400 BP, their origin, comparison with other areas, and relationship with global paleoenvironmental changes. These units were produced after the incision phase that marked the end of the large Holocene accumulation (unit H1) around 1400 BP (at the end of the Late Roman Epoch). Morphosedimentary records enable us to establish three aggradation units during the last 1400 years: unit H2 (ca. 1400–650 cal BP); unit H3 – with two H3A subunits (ca. 650–500 cal BP) and H3B (ca. 500–320 cal BP); and the H4 unit (after 320 cal BP). These units are organized following five types of aggradation/incision arrangements with differing complexities. There are also connections among these units and two slope stages in the region. Finally, the genetic relationships between these units and global paleoenvironmental changes are shown (LALIA, MCA, and LIA) and related to anthropic activity. This contribution is the first detailed and systematic approach to the study of morphosedimentary units and sedimentary arrangements during the Recent Holocene in the Mediterranean area. [ABSTRACT FROM AUTHOR]

During the last 3 ka, different human communities occupied the Bay of Cádiz (SW Spain), including Phoenician, Carthaginian, Roman, Medieval and Modern settlements. Traces of such historical occupations have been recognized along the bay from a geoarchaeological point of view. Some of them bear a palaeogeographical interest related to the historical location of the shoreline. At the same time, Holocene sedimentary units and geomorphological elements identified along the bay can be interpreted as evidences of its morphological evolution. The objective of the present paper is to represent all the available data about archaeological sites and geomorphology in the northern Bay of Cádiz, with the aim of combining both sources of data for elaborating a simple proposal of landscape evolution during the last 3 millennia. The base for mapping was multiple, from historical aerial photographs to satellite imagery and a digital terrain model with a maximum resolution of 0.35 m. [ABSTRACT FROM AUTHOR]

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. • Geomorphology of faulted paleosol sequences allows exploration of tectonic landscapes. • Paleosols are used as proxies to build OIS-based geochronological analogues. • The used methodology analyzes past surface faulting seismic events in SE Spain. • Proposed geochronological analogues allow the relative dating of past earthquakes. • Use of paleosol sequences as a valuable tool in paleoseismic investigations. [ABSTRACT FROM AUTHOR]

Granitic boulders are widespread geomorphological elements, particularly found in humid granitic areas. Although they seldom represent a hazard for people or infrastructures, sometimes their location in steep or natural slopes may jeopardise their stability and potentially affect people or infrastructures. In addition, their complex geometry makes the instability mechanisms difficult to identify, so it is even more difficult to compute factors of safety regarding their stability. In this paper, the authors analyse potential failure mechanisms of granite boulders based on analytical mechanic calculations and physical tilt tests, permitting understanding the phenomena under scrutiny. Then, they study the stability of one of these boulders: the Pena do Equilibrio or equilibrium rock. To do that they resort to standard geotechnical characterization and advanced geometrical characterization derived from UAV photogrammetric and 3D Laser Scanning of the boulder. The presented results exemplify how the application of these recently available topographic technologies, in combination with rock mechanics approaches, enable a rigorous analysis of the stability of granite boulders. • Failure mechanisms of granite boulders have been analysed through analytical calculations and tilt tests in laboratory. • Pena do Equilibrio boulder, located in NW Spain, has been selected for the presented analysis. • UAS and Terrestrial Laser Scanner have been resorted for geometrical calculations like volume and position of the centroid. • The stability of the granitic boulder has been assessed through rock mechanics approaches combined with remote sensing techniques. • A 3D-printed 1:50-scale plastic replica of the boulder has been utilized for analyzing results in laboratory. [ABSTRACT FROM AUTHOR]

Environmental fluctuations during the Holocene caused important landscape changes in the Central Ebro Basin, which is a very sensitive region due to its semiarid climate, lithology, and continuous human presence. Severe erosion processes hinder palaeoenvironmental and archaeological record preservation. Infills of ephemeral stream valleys in semiarid environments are some of the best contexts for geoarchaeological studies. In this paper, we analyse the geomorphological processes, pedological features, and charcoal and pollen content and composition of the sedimentary sequence of La Poza Valley catchment area, with the support of additional information from La Bajada Valley. 14 C dates for 13 charcoal fragments provide the necessary chronological control. We describe 5 sedimentary units and a polycyclic sequence of six soils that covers most of the Holocene, beginning ca. 9.5 ky cal BP. Buried soils help to identify stability periods in the sedimentary sequence, while incision stages are detected through erosive contacts and terraced organisation of the sedimentary units. Charcoal and pollen content and composition, as well as the soil development, reveal an open forest of junipers and pines for the Early Holocene in the lower part of the sequence (mainly in Unit 1), very different from the current deforested landscape, also represented in the sequence (Unit 4). Thus, La Poza record shows the environment was favourable for hunter-gatherers from the Late Mesolithic and for the first Neolithic farmers. From then on, progressive degradation due to a combination of climate changes and increasing human pressure led to the current deforested landscape. [ABSTRACT FROM AUTHOR]

The Ebro Basin constitutes one of the most representative territories in SW Europe for the study of prehistoric societies during the Pleistocene-Holocene transition. The correlation of palaeoenvironmental and geomorphological proxies obtained from sedimentary records with chronologically well-constrained reference archaeological sites has allowed defining this time frame precisely, such that three main pilot areas haven been broadly depicted: the Alavese region, the Pre-Pyrenees and the Bajo Aragón. Overall, the human imprint in the Ebro Basin was rare during the Upper Palaeolithic, but more visible from the Upper Magdalenian (14500–13500 cal BP) to Neolithic times (up to 5500 cal BP). Local environmental resources were continuously managed by the prehistoric communities in the different areas of study. In fact, the Ebro Basin acted during those millennia as a whole, developing the same cultural trends, industrial techniques and settlement patterns in parallel throughout the territory. However, some gaps exist in the 14 C frequency curve (SCDPD curve). This is partially related to prehistoric sites in particular lithologies and geological structures that could have partly been lost by erosional processes, especially during the Early Holocene. In addition, this gap also parallels the reconstructed climate trend for the Pre-Pyrenean and the Bajo Aragón areas, which are defined by high frequencies of xerophilous flora until ca. 9500 cal BP, suggesting that continental climate features could have hampered the presence of well-established human communities in inland regions. The interdisciplinary research (archaeology, geomorphology and palaeoclimatology) discussed in this paper offers clues to understand the existence of fills and gaps in the archaeological record of the Ebro Basin, and can be applied in other territories with similar geographic and climate patterns. [ABSTRACT FROM AUTHOR]

This paper explores the Late Antique occupation of rural territories in the eastern part of the island of Mallorca (Balearic Islands). Data and ceramics from several old field surveys have been re-analysed and different spatial analyses have been carried out in order to understand better the settlement patterns in this area of variable geomorphology, which includes plains, hills and coastlands. Evidence of Late Roman, Vandal and Byzantine occupation is discussed. The study of the ceramic materials enables us to investigate differences between the various historical periods of Late Antiquity on the island. The results show a significant decrease of occupied sites in the Late Roman period as compared to Early Roman times, and a slight recovery through the Vandal and Byzantine periods. The paper also explores the phenomenon of the re-occupation of pre-Roman indigenous sites, the continuity or discontinuity of Roman sites and new foundations in previously unoccupied locations. Overall, the results allow us to produce a first impression of the countryside in this area of Mallorca, in which a remarkable degree of continuity in site location coexists with a range of changes in the nature and appearance of rural settlement. [ABSTRACT FROM AUTHOR]

Abstract: Rodríguez-Ramírez and Yáñez-Camacho (2008), Rodríguez-Vidal et al. (2009) and Rodríguez-Ramírez et al. (2009) have kept an ongoing discussion about the validity of radiocarbon ages in reconstructing Holocene palaeogeographical models in the Gulf of Cadiz. The discussion considered the validity and correctness of the ΔR value to be used in the area to calibrate radiocarbon ages of marine samples. These papers suggest that the ΔR value proposed by Lario (1996) and Dabrio et al. (1999, 2000) is erroneous, and consequently, that all the evolutionary models based on radiocarbon ages from marine samples that have been proposed in this area since 1996 must be revised. However, the papers commented here use erroneously the R, regional R and ΔR values. After reviewing the published data, it is apparent that the most reliable values of ΔR in the Gulf of Cadiz for middle-late Holocene samples range between ΔR =35±85yr and ΔR =95±15yr. This means that the values used in Lario (1996) and Dabrio et al. (1999, 2000) fall in this range, and also that the calibrated ages used by several authors adopting these values are fully reliable. Calibrations using ΔR values inside this range do not yield significant differences in terms of geological age owing to the magnitude of errors resulting from the methods employed. [ABSTRACT FROM AUTHOR]

One of the many factors that leads to soil erosion is rainfall erositivity, which is a basic physical factor enabling us to understand the geomorphological processes that take place in a basin. Results worldwide have shown that the erositivity R factor of the Universal Soil Loss Equation (USLE) has a high correlation with soil loss. In the past there have been few pluviometers capable of recording rainfall with continuous measurements. As a result of this lack of accuracy in the available series of rainfall intensity data, the calculation of the R factor has been restricted for a long time and various simplified models were developed on an international scale that relied on information obtained from existing stations. However, the modernisation of stations over the last few decades has provided to be a valuable tool for validating models, as well as for designing others that are more hardwearing and correlate better with the available information. In this paper, we have calculated the rainfall erositivity R factor for a semiarid basin in SE Spain using the formula developed in the USLE model for a series of 20 years of rainfall with 5-minute intervals, obtaining the mean R factor value of 620 MJ/ha·mm/h per year and maximum values of up to 6000 MJ/ha·mm/h per year. In addition, a comparative analysis of various simplified expressions was carried out to obtain the R factor. To obtain this value, we came up with a simplified equation based on annual maximum daily rainfall and average monthly rainfall, which resulted in a correlation coefficient of r = 0.936 and a P-value of 0.033 for the basin under study. Thus, from this structure of the equation we have compiled a series of parametric maps which enable us to calculate the R factor from any position within the basin under study. [ABSTRACT FROM AUTHOR]

Abstract: 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 218–209BC and AD1755 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 (700–1000years) in this area. [Copyright &y& Elsevier]

Abstract: The application of the regional marine 14C reservoir effect (ΔR) to obtain an accurate calibration of conventional marine shell 14C dates requires prior research concerning the oceanographic conditions and the ΔR of that region. Rodríguez-Ramírez and Yánez-Camacho [A. Rodríguez-Ramírez, C.M. Yánez-Camacho, Formation of chenier plain of the Doñana marshland (SW Spain): Observations and geomorphic model, Marine Geology 254 (2008) 187–196] and afterwards A. Rodríguez-Ramírez, J.A. Morales, J. Borrego and E.G. San Miguel in a reply [A. Rodríguez-Ramírez, J.A. Morales, J. Borrego, E.G. San Miguel, Reply to the comment on “Formation of chenier plain of the Doñana marshland (SW Spain): Observations and geomorphic model” by A. Rodríguez-Ramírez and C.M. Yáñez-Camacho [Marine Geology 254 (2008) 187–196], Marine Geology 263 (2009) 123–125] to the comment by J. Rodríguez-Vidal, F. Ruiz and L.M. Cáceres on the paper mentioned above [J. Rodríguez-Vidal, F. Ruiz, L. M. Cáceres, Comment on “Formation of chenier plain of the Doñana marshland (SW Spain): Observations and geomorphic model” by A. Rodríguez-Ramírez, C.M. Yáñez-Camacho [Marine Geology 254 (2008) 187–196], Marine Geology 263 (2009) 120–122] use, in both cases, not only incorrect ΔR values for the calibration of 14C dates obtained from shell samples collected from the east coast of the Gulf of Cádiz, but they also confuse the ΔR concept with that of R(t), the 14C reservoir age. Because the misunderstanding of these concepts by these authors and, in the first case, also their failure to take into account the ΔR values obtained by us (and already published) from the east coast of Gulf of Cádiz, all the calibrated dates presented either in the first paper or in the reply cannot be accepted. Here I present a new calibrated dataset using accurate ΔR values and I recommend that the conclusions obtained by Rodríguez-Ramírez and their collaborators be revised, as J. Rodríguez-Vidal, F. Ruiz and L.M. Cáceres proposed in their comment. [Copyright &y& Elsevier]

Abstract: This special issue of Geomorphology consists mainly of selected papers from the S15 Session: GIS and SDA applications in Geomorphology at the 6th International Conference on Geomorphology held in Zaragoza (Spain) in September 2005. For this session, 53 abstracts from Europe, Asia, the Americas, Africa and Oceania were submitted, and 18 oral communications and 35 posters were presented. The session provided an opportunity to overview, discuss and evaluate new advances of GIS (Geographical Information Systems) and SDA (Spatial Data Analysis) applications in the field of geomorphology. Eight of the manuscripts submitted for the publication call for this special issue survived the review process, and two other invited contributions together form this special issue with 10 papers. [Copyright &y& Elsevier]

Abstract: Over the last forty years, applying dendrogeomorphology to palaeoflood analysis has improved estimates of the frequency and magnitude of past floods worldwide. This paper reviews the main results obtained by applying dendrogeomorphology to flood research in several case studies in Central Spain. These dendrogeomorphological studies focused on the following topics: (1) anatomical analysis to understand the physiological response of trees to flood damage and improve sampling efficiency; (2) compiling robust flood chronologies in ungauged mountain streams, (3) determining flow depth and estimating flood discharge using two-dimensional hydraulic modelling, and comparing them with other palaeostage indicators; (4) calibrating hydraulic model parameters (i.e. Manning roughness); and (5) implementing stochastic-based, cost–benefit analysis to select optimal mitigation measures. The progress made in these areas is presented with suggestions for further research to improve the applicability of dendrogeochronology to palaeoflood studies. Further developments will include new methods for better identification of the causes of specific types of flood damage to trees (e.g. tilted trees) or stable isotope analysis of tree rings to identify the climatic conditions associated with periods of increasing flood magnitude or frequency. [Copyright &y& Elsevier]

Abstract: Gyprock is a common rock in evaporitic formations, which have a wide distribution across all continents. However, outcrops of gyprock are rather limited, occurring mainly in low rainfall areas (i.e. southwest of USA, Italy, Spain). Gyprock is one of the most common lithology in the Ebro Tertiary Basin. Here, semiarid conditions propitiate the development of specific weathering processes and landforms with significant implications for understanding the genesis of soils and the geomorphological evolution of these areas. Gypsum crystallization within the pores and fissures of gyprock close to the surface leads to volume increase and pressures, with the consequent weathering of this rock. As a result, considerable porosity develops producing peculiar morphologies on gyprock outcrops (domes and decimetre-scale blisters), specific microscopic features (voids with plain walls, horse-shoe pores and serrated pores), as well as microscopic fabrics (grating fabric, skeletal fabric, fan fabric and botryoidal fabric). This paper presents a morphological characterization of the material forming the various types of weathering features, from microscopic to mesoscopic scale. The macromorphology and micromorphology of those features were used to interpret their genesis. [Copyright &y& Elsevier]

Abstract: 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 ~183–130ka (Terrace BT1, elevated ~25m above the modern river channel) and ~111–26.8ka (BT2, ~18–20m above the modern river channel), punctuated by ~20m 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 ~24.5–14.2ka (BT3); 10.6–9.8ka (BT4); 8.3–6.2ka (BT5) and ~3ka (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. [Copyright &y& Elsevier]

Abstract: This paper is based on the combination of a Geographic Information System (GIS) and tools or multi-criteria decision making (MCDM) methods in order to obtain the evaluation of the optimal placement of photovoltaic solar power plants in the area of Cartagena (Region of Murcia), in southeast Spain. The combination GIS–MCDM generates an excellent analysis tool that allows for the creation of an extensive cartographic and alphanumeric database that will later be used by multi-criteria methodologies to simplify problems to solve and promote the use of multiple criteria. In GIS two types of criteria will be reflected: constraints or restrictive criteria, and weighting criteria or factors. Constraints or restrictive criteria will make it possible to reduce the area of study by discarding those areas that prevent the implementation of renewable energy plants. These criteria will be obtained from the legislation (planning regulations, protected areas, road networks, railways, waterways, mountains, etc). Weighting criteria or factors will be those which, according to the objective to be reached, influence the ability to solve a concrete alternative. The choice of such criteria is marked by the influence presented to the overall goal; in this case they will be location, geomorphological, environmental and climatic criteria. Through the use of MCDM the criteria or factors mentioned will be weighted in order to evaluate potential sites to locate a solar plant. Analysis and calculation of the weights of these factors will be conducted using Analytic Hierarchy Process (AHP). The assessment of the alternatives according to their degree of adequacy is carried out through the TOPSIS method (Technique for Order Preference by Similarity to Ideal Solution). [Copyright &y& Elsevier]

This paper examines storm-induced morphological and hydrodynamic changes after a submerged and a detached breakwater were constructed at La Barceloneta beach (Barcelona, NW Mediterranean) in 2006-2007. The shoreline configurations before and after beach nourishment and the construction of the protective structures were compared using a video dataset comprising 29 storm events spanning the pre- (2001 to 2005, n = 17) and the post-breakwater situation (2006 to 2011, n = 12), and hydrodynamic modelling based on the SMC coastal modelling system. As a result of the protection works, La Barceloneta was subdivided into two beaches separated by an artificial salient. The analysis of shoreline response to storms has been improved by using the shoreline hyperbolic tangent fit to represent the beach planform. Comparing the pre- and post-breakwater situations on the basis of these shoreline fits facilitated the identification of beach rotation processes because interference by smaller-scale morphological features was eliminated (e.g. the formation, changes in shape or migration of mega-cusps). In the current post-breakwater situation, there is evidence for a change in the behaviour of the north-eastern beach triggered by the submerged breakwater built in 2007. Furthermore, a counter-clockwise beach rotation has occurred at the north-eastern beach, whereas the south-western beach has experienced a clockwise beach rotation. This morphodynamic behaviour is caused by a new, complex wave-induced circulation system comprising two dominant alongshore currents flowing in opposite directions. In contrast to the pre-breakwater situation, the alongshore component of the radiation stress does not accomplish beach rotation in the post-breakwater situation. [ABSTRACT FROM AUTHOR]

This special issue of Geo-Marine Letters presents selected contributions from the 6th Spanish Conference on Coastal Geomorphology held from 7-9 September 2011 in Tarragona, Spain. The guest editors are Isabel Montoya Montes, Maria J. Sánchez García and Inmaculada Rodríguez Santalla. These conferences on coastal geomorphology are held biannually and serve as a discussion forum focusing mainly on advances in knowledge about the dynamics of the Spanish littoral environment, although contributions from other coastal regions are encouraged. The papers presented in this Special Issue provide a selective view of the latest research results, the main topics dealing with recent coastal morphodynamics and longer-scale coastal evolution. The 7th Conference will be held in July 2013 in Oviedo, Spain, organized by the Department of Geology at the University of Oviedo. [ABSTRACT FROM AUTHOR]

Abstract: This paper is concerned with the effect of sediment accumulation on shore platform development. Boulder accumulations are common on the granitic shore platforms of Galicia, northwestern Spain. Boulders are produced by erosion of shore platforms and of cliffs consisting of cold-climate deposits from the last glacial period. Measurements were made of the long axis length of more than 800 boulders, and additionally of the short and intermediate axes of 340 of these boulders, as well as of their orientation and gradient. There were two study areas. The boulders on the Barbanza Peninsula are generally a little smaller than those in southern Galicia with, respectively; mean long axis lengths of 0.98 and 1.14, and masses of 1.06 and 1.59t. There are also some isolated, very coarse boulders and megaclasts in southern Galicia. The distribution and extent of the deposits and boulder imbrication and orientation testify to the high levels of wave energy produced by northwesterly and westerly storms in this region. Although the boulders, as well as the underlying shore platforms, were inherited, in part, from previous interglacial stages, some boulder detachment and movement is occurring today during storms, when significant deep water wave heights exceed 8 to 10m. Despite some abrasion of the shore platforms, the primary effect of large boulder accumulations is protective. The role of sediment on shore platforms has been neglected, but this study suggests that because of arrested development under thick accumulations, platform gradient in areas with abundant sediment increases with the grain size of the material. The occurrence and type of sediment on shore platforms may therefore help to explain the distribution of sloping and subhorizontal platforms under different morphogenic and geological conditions. [Copyright &y& Elsevier]

Abstract: The study area is the Bajo Segura Basin, located in the easternmost sector of the Betic Ranges. The existence of a wide coastal lagoon occupying the depressed spaces (at least since the Middle Pleistocene) has been inferred, in previous works, from the stratigraphic, micropaleontological and sedimentological analyses. Particularly during the Upper Holocene the environmental morphology was modified. This paper aims to correlate the geomorphological, sedimentological and micropaleontological data with archeological and geoarcheological information of the Upper Holocene. This will allow to hypothesize the recent environmental evolution and its relation to human settlement. The geomorphological approach consists in the analysis of six mechanical cores and geoarcheological studies in several sites. Archeological data is based on sites dating to the 2nd millennium B.C. (Bronze Age), 725–550 B.C., 8th–6th centuries B.C. (Early Iron Age), 550–206 B.C. (Iberian Age), 6th–3rd centuries B.C., 206–500 B.C. (Roman Age), 3rd century B.C.–5th century A.D. and 500–900 A.D., 5th–8th centuries A.D. (Early Middle Ages). During the Bronze Age, the Bajo Segura Basin was occupied by a coastal lagoon with marine communication. The fossil assemblage indicates a greater marine influence near the coast and fresher conditions further away from it. At least since the subsequent period, and especially since the Iron Age, an activation of the alluvial processes is recorded establishing paleogeographical changes in the lagoons. During the roman period the southern landscape (Segura River) is dominated by the flood plain with associated lagoons and freshwater marshes, at least in the inner part. To the north, the Vinalopó alluvial fan progrades and reduces the dimensions of the lagoonal areas. The swampy conditions remained until the Modern Age. Agricultural expansion reached its maximum development in the 18th century A.D. and gave rise to the present landscape. [Copyright &y& Elsevier]

Abstract: Active tectonic deformation influencing the streams and hillslopes of the Sierra Alhamilla ridge (anticlinorium) in southeast Spain is related to the dextral-reverse Polopos Fault Zone to the north and east of the ridge and to normal faulting in the southern side of the ridge. A fault segmentation and fluvial terrace mapping is presented in this paper. The following geomorphic indices were calculated in the area: the mountain-front sinuosity, valley floor width-to-height ratio, drainage basin asymmetry factor, basin hypsometric curve and integral, longitudinal river profile and stream-length gradient index normalized by the graded river gradient (SLk index). The SLk map shows two sets of high anomalies: a) an E–W-striking anomaly, due to the dextral-reverse Polopos Fault Zone located in the northern limb of the anticlinorium; b) a group of NNW–SSE-striking anomalies, associated with Pliocene–Quaternary NW–SE- to NNW–SSE-striking high-angle normal faults that cut the southern limb. Late Pleistocene–Holocene activity occurred along the North Alhamilla Reverse Fault and the dextral transpressive South Gafarillos Fault, two segments in the Polopos Fault Zone. The former fault produces rejuvenation of the streams at the base of the northern slope. In this area, mountain-front sinuosity and valley floor width-to-height ratio suggest Quaternary uplift rates between 0.05 and 0.5mky−1. Holocene to present-day activity of the South Gafarillos Fault is demonstrated by faulted late Pleistocene terraces and Holocene colluvial deposits and suggested by deflected streams that have complex or convex hypsometric curves. Pliocene–Quaternary high-angle normal faults control the relief in the southern limb and the western end of the Sierra Alhamilla. These faults produce low mountain-front sinuosity and valley floor width-to-height ratio indices typical of uplift rates quite higher than field-based rates from some other studies. [Copyright &y& Elsevier]

Abstract: In this paper, we present a critical analysis of the distribution of Paleolithic sites between the Massif Central and the Pyrenees (southwestern France) to understand the settlement patterns during the last climatic deterioration of the Quaternary period. This analysis used recent stratigraphic and archaeological data from thousands of systematic test pits conducted for rescue archaeology in different geomorphological contexts. Our analysis addresses crucial questions about the role of the Garonne alluvial plain in this territory during the Upper Paleolithic. The implications are discussed in the context of this region of Europe, which was considered to be a favorable zone for human occupation during glacial periods. The conclusions reveal a division of this territory into two parts separated by a large unoccupied or rarely occupied zone. We discuss perspectives not only concerning the territoriality of the prehistoric groups who lived on the margins of this no man’s land, but also the cultural endemism that could have led to this geography, influenced by climatic conditions clearly more rigorous than previously recognized in this region. [Copyright &y& Elsevier]

Abstract: The northern slope of the Sierra de Aitana (Eastern Betic Cordillera) is characterized by a long mountain front with a prominent Eocene limestone scarp overlying ductile Eocene marlstones. This stratigraphic feature and the highly stepped topography produced by several normal faults favor gravitational processes such as rock avalanches, rock slides and rock falls. This paper reports a compound landslide comprising a rotational rock slide and slab-type lateral spreading affecting these materials with blocks of volumes up to 106 m3. This lateral spread process produced singular and spectacular morphological features, the Simas de Partagat, which are trenches 20m wide and up to 40m deep, formed by the widening of discontinuities. The use of a differential SAR interferometry technique for monitoring this landslide over a time span of 11yr has revealed that velocity of movement is insignificant, with rates comprised between 0 and 2mmyr−1 and cumulative negligible displacements. Individual rock blocks initially located at the free face of the scarp were affected by slides at the base of the scarp, descending from a few to several dozen meters along the slope. Blocks broke up as displacement progresses, with several in different stages of evolution being recognizable along the slope. Differential SAR interferometry shows a greater activity in the area north of compound landslide, although velocity is extremely low (below 16mmyr−1). This extremely slow movement revealed by interferometry is in agreement with other geological and geomorphological evidence such as the existence of speleothems and cemented breccias against the head walls of the trenches. Both deposits are indicative of a long period of discontinuity widening. Also, undisturbed debris deposits covering ancient rock slides are indicative of very slow gravitational processes characterized by long dormant periods. In addition, a historical picture from 1898 shows nearly negligible change in the Simas de Partagat over this 112yr period. [Copyright &y& Elsevier]

Summary: The roughness calibration of floodplain and channels represents an important issue for flood studies. This paper discusses the genesis of scars on trees and their use as benchmarks in roughness calibration. In addition, it presents a methodology to reconstruct unrecorded flood discharge in the Alberche basin of the Spanish Central System. The study is based on the combined use of dendrogeomorphic evidence (i.e. scars on trees), data from the Navaluenga flow gauge (Avila Province) as well as a 1D/2D coupled numerical hydraulic model. A total of 49 scars have been analyzed with dendrogeomorphic techniques. Scar dates are in concert with seven flood events documented in the systematic record (i.e. 1989, 1993, 1996, 2000, 2002, 2003, and 2005). We were also able to identify an additional event dated to 1970, which is before the flow gauge was installed at Navaluenga. Based on the rating curve obtained from the flow gauge, cross-sectional area and data from hydraulic modelling, we cannot find a statistically significant difference between water depths registered at the flow gauge and scar heights on trees (p-value>0.05), indicating that scars would have been generated through the impact of floating wood and that scars on trees would represent a valuable and accurate proxy for water depth reconstruction. Under this premise, we have estimated the peak discharge of the 1970 flood event to 1684.3±519.2m3 s−1; which renders this event the largest documented flood for the Alberche River at Navaluenga. In a last analytical step, we discuss the use of scars on trees as benchmark for roughness calibration in ungauged or shortly recorded basins and address the added value of dendrogeomorphic data in flood frequency analysis. [ABSTRACT FROM AUTHOR]

Abstract: The Messinian Salinity Crisis (MSC) drastically affected the physiography, morphology and sedimentation all along the Mediterranean area at the end of the Miocene. This paper presents an analysis of the effects of the MSC on the Catalan continental margin, based on a broad database of seismic reflection profiles from the oil industry and academy. We study the sedimentary processes and their controlling factors and the correlation with the nearby and well-known Gulf of Lions. Because of the complexity of the MSC, we define the Margin Erosion Surface/Top Erosion Surface (MES/TES) as the surface marking the end of the Messinian event, which allows differentiating three domains along the Catalan margin: the Creus, Girona and Barcelona domains, separated by the Palamós and Blanes canyons. The Creus domain shows an important structural control on the MES/TES physiography, while the Girona and Barcelona domains are characterized by wide and flat MSC platforms below the present-day shelf. The entire margin developed a series of complex drainage systems as the result of the Messinian sea level drop. The location of the main valleys (Cap de Creus paleo-drainage system, Palamós and Blanes paleo-canyons and the downslope-trending valleys on the Barcelona domain) was directly controlled by the structural framework. In contrast, the Barcelona paleo-drainage system and the tributaries of the Blanes and Palamós systems were excavated by direct subaerial erosion by meteoric rain in the basins limited by basement blocks, and were afterwards totally filled by the Pliocene–Quaternary sedimentation. Regarding the MSC depositional features, the major part of the eroded sediment was deposited as detrital deposits on the foot of the slope. The distribution of detrital bodies and evaporites was also structurally controlled. A Zanclean sea level rise occurring in at least two phases is confirmed by this study, in correlation with interpretations from the Gulf of Lions. [Copyright &y& Elsevier]

Abstract: Coastal lagoons are valuable water bodies since they are of great ecological and economic interest throughout the world. Their existence is controlled by variations in sea level and the geological substrate of their location. Their morphology is linked to local topography, alternation of high and low pressure, the presence of a river, as well as tidal regime. All these factors influence lagoons along the coastline in the south of Spain. The main morphological characteristics of such lagoons are the following: intermittence, one-dimensional morphology, small size, shallow waters, high area/depth ratio, no flood- or ebb tide deltas, overwash of their low barriers during storms, high evaporation rates and feeding by rivers. Effective management of these systems requires the evaluation not only of their hydrodynamics and opening and closure rate, but also the prediction of possible future scenarios as a response to meteorological events. This paper describes the behavior of a coastal lagoon in Zahara de los Atunes (Cádiz) by means of a numerical model implemented with the objective of serving as a tool for optimizing the coastal zone management. Although the coastal lagoon at Zahara de los Atunes is closed most of the year, it is artificially opened at the beginning of the summer. The results of our study showed that during this period, the lagoon is flood-dominated with a pumping-mode response. It naturally tends to close since it is a trap for littoral drift sediments. The precise date of closure depends on the events that take place during the autumn, which determine whether the sediments deposited in the inlet by the littoral drift are flushed out by the river flow or flushed in by the waves. [Copyright &y& Elsevier]

Abstract: This paper presents a kinematic study of the Portalet landslide (Sallent de Gállego, Central Spanish Pyrenees), which was triggered by the construction of a big parking area at the toe of the slope. A description of the landslide from a geomorphological point of view is first introduced. The measurements of displacement performed by conventional (total station, inclinometers and differential GPS) and advanced (GB-SAR) ground monitoring techniques are presented and GB-SAR and DGPS datasets are compared. The correlation between measured displacements and rainfall series indicates that the landslide is very sensitive to rainfall. The continuous GB-SAR measurements from the 5th of October 2006 to the 21st of November 2006 at a rate of 1/h were used to calibrate a simple 1D infinite model by back analysis. The model includes a viscoplastic behaviour and takes into account directly the known daily rainfall intensity and the dissipation of the excess pore-fluid through a simple consolidation equation. Prediction was made in an extended period of time, from May 2006 to July 2007, and compared to the DGPS measurements. [Copyright &y& Elsevier]

Abstract: This paper presents an analysis of the dune field dynamics of El Fangar Spit in the Ebro Delta (Spain), associating it with the internal structure of dunes carried out with ground-penetrating radar and supported by data from topographic DGPS. These analyses are of great importance to ascertain the state of the internal structure of dunes as an important element in their stability and, therefore in their evolution. The internal structure shows accretion and progradation sequences of dunes over beach deposits, which depend on dune morphology (height, crest orientation) and location, as well as the processes acting on them. [Copyright &y& Elsevier]

This paper explains the value as geomorphological heritage of the Valsain valley, situated in the Sierra de Guadarrama (Central Spain). It is assumed on it that landforms are a part of the whole nature, and are strongly associated to it. Human use has transform this valley into a landscape where geomorphology, nature and culture form a complex unit, that is explained through the way in which was used and understood during the XVI century. [ABSTRACT FROM AUTHOR]

Abstract: It is paradoxical that work in question (Rodríguez-Ramírez and Yánez-Camacho, 2008) has started a debate in the scientific community about the values of the reservoir effect used in the 14C dates in the Gulf of Cádiz, since in their Comments Rodríguez-Vidal et al. (2009), Monges Soares (2010-this issue) and Lario et al. (2010-this issue), have not taken into account that these values are in reference to earlier studies (Morales et al., 2008). The new figures suggested by Rodríguez-Vidal et al. (2009) and Monges Soares (2010-this issue) for this part of the Gulf of Cadiz (Soares, 2008) had not been reported when the earlier papers were accepted and published. The values for the reservoir effect applied on the South Atlantic coast of the Iberian Peninsula need to be continually adjusted, due to the new contributions that have been made in recent years as a result of developments of the research being undertaken in this field. Without doubt, in the future, as further progress is made, the values will be even more finely tuned and the present ones will become obsolete, as our understanding of marine and estuarine dynamics in this sector over the last few thousand years is a topic which remains open to new interpretations. The new figures for the reservoir effect are an important contribution in determining more accurately the chronology of events in the Holocene, and they make it necessary to revise the previous studies on marine Holocene formations in the Gulf of Cadiz with 14C dates, owing to the errors that have occurred in this respect. For this reason the Comment should not be aimed at one paper alone, and instead this matter should be reviewed at a regional level. Those of us who are not specialists in the topic welcome these clarifications, which can help shed additional light on the chronological problems. [ABSTRACT FROM AUTHOR]