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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]

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: 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: The Le Danois Contourite Depositional System (CDS), located in an intraslope basin along the Cantabrian margin, is unique with respect to the known sedimentary systems along the upper slope of the Biscay margin. Whereas the steep Biscay slopes are dominated by downslope processes, the Le Danois CDS has been generated by alongslope processes and has a strong potential to contain a record of the Neogene palaeoceanography. This paper will focus on the onset, development and present-day functioning of this system with respect to its unique morphological control and the responsible local oceanographic processes. New bathymetric and seismic reflection data show that the past and present Le Danois CDS is shaped by the Mediterranean Outflow Water, conditioned by seafloor irregularities and two topographic highs; the large Le Danois Bank and the smaller Vizco High. The seismic stratigraphic analysis carried out on the contourite deposits has allowed to identify 3 seismic sequences, separated by 3 major regional discontinuities. Changes in depositional styles, the vertical stacking of seismic units and the nature of the discontinuities suggest a correlation with the development of the Cadiz CDS and well-known palaeoceanographic events along the NE Atlantic margin. The first clues for bottom-current deposits are identified in the Lower Sequence, which is developed after tentatively the Lower Pliocene. The drift deposits of both the Lower and Middle Sequences were confined into two palaeobasins within the intraslope basin. However, from the Middle Pleistocene Revolution (0.9Ma) onwards, the contouritic deposition is intensified due to the switch to a “full glacial” mode with 100ka cyclicity. This has allowed the development of the present-day depositional and erosive features, such as respectively elongated mounded and separated drifts, plastered drifts, moats and slide scars. [Copyright &y& Elsevier]

Abstract: The Guadalquivir estuary is one of the most important in Europe. It is isolated from the sea by two important littoral spits (Doñana and La Algaida). Its sedimentary filling occurred as a result of deltaic contributions of the Guadalquivir River, giving rise to marshes primarily composed of mud deposits, among which a succession of sandy and shelly ridges can be found. The aim of this paper is to explain the genesis and evolution of these sandy and shelly ridges clarifying what types of ridges are found and their spatial distribution, identifying the processes responsible for their formation. These ridges extend in the form of long strands along the estuary, influencing its evolution during the Late Holocene. The geomorphologic and lithostratigraphic features of these ridges allow them to be defined as transgressive cheniers, regressive cheniers and laterally accreted ridges (spits), as components of the Guadalquivir estuary chenier plain complex. This chenier plain has the peculiarity of developing on a semi-enclosed shoreline, contrary to other chenier plains in the world, which develop on open coasts. In the Guadalquivir estuary the chenier plain formation is related to two relatively higher sea level (4200–2800 yr BP and 1400–1000 yr BP) during which high energy events occur (storms and tsunamis), that transgressed the large littoral spits. The Carrizosa (∼4000 yr BP) and Vetalengua (∼1400–1300 yr BP) spits have been formed across the inlet, and prograded landwards of the estuary. From here, several sequences of cheniers (mainly transgressive cheniers) associated with these events were formed. These cheniers form two groups: Las Nuevas (∼1100–1000 yr BP) and Marilópez (∼3000 yr BP), composed mainly of shells and shell fragments. These cheniers were constructed by waves which reworked the shells above estuarine levees, and led to their intense landward migration, thus explaining the peculiar, high inland position of the cheniers. [Copyright &y& Elsevier]

Abstract: The geological characterization of the Galicia Bank Region, in the NW Iberian continental margin (Atlantic Ocean) was the marine geology community''s response to the environmental risk posed by the sinking and oil spill of the Prestige tanker. This special volume of Marine Geology is a collection of papers that address themes of general interest for marine geohazard determination and assessment. A variety of topics associated with morphology, stratigraphy, sedimentology, tectonism and seismicity were considered in order to define the geohazards at the location of the Prestige wreck, which still has oil in its tanks. These studies have also served to provide greater detail and high-resolution datasets on the geological evolution of the Galicia Bank Region in general, and particularly its SW flank. [Copyright &y& Elsevier]

Carchuna beach, located on the southeast coast of Spain, has a series of natural permanent horns of time-dependent horizontal dimensions, which do not appear to be periodically spaced, and do not propagate alongshore. Until at present, it has been assumed that the permanency of these forms is related to the existence of bed rocks; nevertheless, analysis of the configuration of the depth contours and the bed sediment composition does not justify this hypothesis. This paper explores the formation of cuspate features by the effects of the wind wave dynamics and their development by nearshore circulation and infragravity waves, including edge waves. Three levels of wave energy flux conditions are considered. In all likelihood, wave refraction of severe storms on submerged fluvial valleys is the main cause for longshore variation of breaking wave height, which seems to be one of the initial conditions necessary for the cuspate to initiate. Moderate storms enhance the deepening of the embayments, whereas mild sea states are able to maintain the features by self-organization. The possibility of the occurrence of edge waves due to the non-linear interaction between the components of a gravity wave spectrum approaching the shore under moderate storm conditions is explored. Preliminary analysis of video images taken by an Argus station seems to confirm this hypothesis. [Copyright &y& Elsevier]

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]