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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: 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]