Comment on “Formation of chenier plain of the Donana marshland (SW Spain): Observations and geomorphic model” by A. Rodriguez-Ramirez and C.M. Yanez-Camacho [Marine Geology 254 (2008) 187–196]

摘要

The application of the regional marine ~(14)C reservoir effect (ΔR) to obtain an accurate calibration of conventional marine shell ~(14)C dates requires prior research concerning the oceanographic conditions and the ΔR of that region. Rodriguez-Ramirez and Yanez-Camacho [A. Rodriguez-Ramirez, C.M. Yanez-Camacho, Formation of chenier plain of the Donana marshland (SW Spain): Observations and geomorphic model, Marine Geology 254 (2008) 187–196] and afterwards A. Rodriguez-Ramirez, J.A. Morales, J. Borrego and E.G. San Miguel in a reply [A. Rodriguez-Ramirez, J.A. Morales, J. Borrego, E.G. San Miguel, Reply to the comment on “Formation of chenier plain of the Donana marshland (SW Spain): Observations and geomorphic model” by A. Rodriguez-Ramirez and C.M. Yanez-Camacho [Marine Geology 254 (2008) 187–196], Marine Geology 263 (2009) 123–125] to the comment by J. Rodriguez-Vidal, F. Ruiz and L.M. Caceres on the paper mentioned above [J. Rodriguez-Vidal, F. Ruiz, L. M. Caceres, Comment on “Formation of chenier plain of the Donana marshland (SW Spain): Observations and geomorphic model” by A. Rodriguez-Ramirez, C.M. Yanez-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 ~(14)C dates obtained from shell samples collected from the east coast of the Gulf of Cadiz, 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 Cadiz, 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 Rodriguez-Ramirez and their collaborators be revised, as J. Rodriguez-Vidal, F. Ruiz and L.M. Caceres proposed in their comment.