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The dune fields of the National and Natural Parks of Doñana are considered one of the most outstanding dune fields in Western Europe. They are located at the west margin of the Guadalquivir river estuary. The accumulation of aeolian sands partly blocks the connection between the ample Guadalquivir River estuary and the Gulf of Cádiz in the Atlantic Ocean. The sand units form a large oval dome, the “Abalario Dome” which connects with the large Doñana Spit Bar where dune systems accumulated as well, at least in part coevally with the spit growth. The most frequent dune morphologies are parabolic or transverse. The degree of activity was classified as stable, semi-active and active. Most stable dunes concentrate on the Abalario Dome, whereas active dunes occur mainly on the Doñana spit bar. Relative chronology was established from the superposition of dune Systems and Subsystems deduced from photogeology coupled with field surveys, orthophotos, and oblique and 3D images. Sampling and radiogenic dating (Optically Stimulated Luminescence-OSL) allowed to date eight dune Systems named as Systems I to VII plus an additional CS, which is a laterally equivalent to part of S IV, V and VI. The proposed ages are: System I, age 11.1 38 to 9.5 ky BP, perhaps extending to 8.5 ky BP. System II, 8.2 to 6.1 ky BP. System III, 5.9 to 2.6 ky BP. 39 System IV, 2.6 to 1.6 ky BP. System V, 1.6 to 1.3 ky BP. System VI, 1.2 to 0.7 ky BP. System VII, 0.7 to 40 0.15 ky BP. The age of the Complex System is 2.2 to 0.15 ky BP. Additionally, it was concluded that genesis of the somewhat-different Complex System (CS) was related to the increased accumulation space created by movements (sliding) along the Mazagón and Torre del Loro faults following major regional seismic activity. Supported by Spanish FEDER-MINECO (projects CGL2015-69919-R, CGL2015-67169-P, HAR2011-23798 and CSO2011-24425) and OAP036/2008.

This work illustrates the state of the art on archaeoseismology of the ancient Roman city of Baelo Claudia (Tarifa, Cádiz) after nearly fifteen years of research. This ancient Roman site was affected by two earthquakes in the years AD 40–60 and AD 260–290 which promoted important urban and architectural changes and eventually the destruction and further abandonment of the city in AD 365–390. Earthquake Archaeoseismological Effects (EAEs) are catalogued, described and mapped in the entire monumental sector of the city mainly witnessing the last earthquake which occurred in AD 260–290. Mapping of oriented EAEs illustrate damage distribution all over the lower sector of the city, as well as the occurrence of suspect coseismic landslide and tsunami events. The structural analysis of oriented EAEs throughout the entire mapped sector suggests that the intervening ground motion was preferentially oriented in a SW to NE direction. The geoarchaeological analysis and some relevant archaeological anomalies, strongly suggest the occurrence of coeval tsunami events during both ancient earthquakes, pointing to the occurrence of an offshore seismic source SSW of the city. Several N-S normal faults have been identified around the Bolonia Bay area and some of them continue offshore SSW of Baelo Claudia. These faults with clear Quaternary activity can be considered as the more probable seismic sources for the events affecting the ancient Roman site and they are consistent with the mapped damage orientation displayed by the structural analysis of EAEs within the old Roman city. El presente trabajo ilustra el estado del conocimiento sobre arqueosismología en la antigua ciudad romana de Baelo Claudia (Tarifa, Cádiz) tras casi quince años de investigaciones. Esta antigua ciudad romana se vio afectada por dos importantes terremotos en los años 40–60 AD y 260–290 AD. El primero de ellos afectó en mayor grado a la parte baja (costera) de la ciudad provocando importantes cambios urbanísticos y arquitectónicos (monumentalización) en respuesta a las labores de reconstrucción. El segundo de ellos provocó una mayor destrucción, cuya ruina progresiva desembocó en el abandono definitivo de la ciudad en el 365–390 AD. Se catalogan, cartografían y describen la mayor parte de los Efectos Arqueológicos de los Terremotos (EAEs) del sector monumental de la ciudad, que testifican los efectos producidos por el terremoto ocurrido en el 260–90 AD. La cartografía de daños (EAEs) muestra la distribución y orientación de los daños en la zona baja de la ciudad, así como la ocurrencia de otros procesos cosísmicos, como deslizamientos y pequeños tsunamis. El análisis estructural del conjunto de daños orientados indica que la dirección de movimiento del terreno se produjo en una dirección dominante del SO al NE. Los análisis geoarqueológicos, así como importantes anomalías constructivas y funerarias, sugieren la intervención de tsunamis de escaso poder de penetración durante los dos terremotos, apuntando a la existencia de una fuente sísmica submarina común al SSO de la ciudad. Se han identificado diferentes fallas normales de dirección N-S en la zona de la Bahía de Bolonia, algunas de las cuales se prolongan hacia el interior del mar en la zona SSO de Baelo Claudia. Estas fallas presentan claras evidencias de actividad Cuaternaria y podrían considerarse como las fuentes sísmicas más probables para los dos antiguos terremotos que afectaron a la ciudad en época romana.