The Late Pleistocene ami Holocene evolution of the estuaries in !he Gulf of Cadiz is interpreted for the first time using drill cores, logs, trenches, and 38 new radiocarbon data, and the results compared with lhe she!f The Odie!, Tinto and Guadalete Rivers deposited conglomerales during a highstand lhat did not reach the present sea level dated al ca. 25-30 ka (Isotopic Stage (IS) 3), corresponding lo a relatively humid period in the area. Rivers incised these coarse-grained deposits during the last main lowsland at ca. 18 ka, when sea level dropped to -120 m and the coastline lay 14 km seawards from !he presenL The erosional surface is a sequence boundary and the f100ding slIrface of tl1e postglacial eustatic rise, overlain by !he valley fill deposits of the transgressive and highstand phases of the last fourth-and fif!h-order depositional sequences recognised in !he shelf The first marine int1uence in the estuaries during the transgression occurs at -25/ -30 m at ca. 10,000 years BP. According to tossil assemblages, the transgressed basins changed fmm brackish to more open marine as !he sea rose lIntil ca. 6500 years BP, when it reached !he maximum f100ding ami the sandy estuarine barriers ceased to retrograde toward the muddy central basins. Then, the rate of eustatic rise decreased drastically, and !he estuarine filling followed a two-fold pattem govemed by the progressive change from vertical accretion to lateral (centripelal) progradation. At ca. 4000 years BP the t1uvial input surpassed !he already negligible rate of rise, causing partial emergence of tidal f1ats and spit barriers in the largely filled estuarine basins. Prevalence of coastal progradation upon vertical accretion al ca. 2400 years BP caused accelerated expansion of tidal t1ats and rapid growth of the sandy barriers. Further changes since the 16th century ref1ect widespread anthropic impacts.

Detailed geological mapping, morphostratigraphic, palaeontological and geochronological (uranium-series) analyses were undertaken on the raised marine terraces and interbedded terrestrial deposits along the Spanish peninsular and insular Atlantic and Mediterranean coasts. Several sets of Pleistocene shallow-marine to coastal deposits exposed in a staircase arrangement are interpreted as being emplaced during sea-level highstands coeval with interglacials or interstadials correlating with marine Oxygen Isotopic Stages (OIS) 5a/5c, 5e, 7, 9/11 and older. Up to three highstands have been identified in deposits formed during OIS 5e. Close to the end of OIS 5e there is a record of sudden changes in sea-surface conditions and climate marked by the disappearance of a major proportion of the warm 'Senegalese' fauna, switches from oolitic to non-oolitic facies, and accumulation of boulder beaches. Dating of the coral Cladocora caespitosa, found in a layer that also contains Strombus bubonius, confirms the occurrence of warm fauna in the Mediterranean basin during OIS 7, as previously suggested by Hillaire-Marcel et al. (1986), Goy et al. (1986a,b), Zazo and Goy (1989). Also the occurrence of warm faunas in deposits corresponding to an older interglacial, probably OIS 9 or 11, in the Balearic Islands suggests similar oceanographic conditions (sea-surface temperature, assuming constant salinity) during the last interglacial and at least two interglacials of the Middle Pleistocene in the western Mediterranean. ß

Since the publication of the paper of Dean (1974), loss on ignition (LOI) has been widely used as a method to estimate the amount of organic matter and carbonate mineral content (and indirectly of organic and inorganic carbon) in sediments. The relationships between LOI at 550°C (LOI 550 ) and organic carbon (OC) content and between LOI at 950°C (LOI 950 ) and inorganic carbon (IC) content are currently accepted as a standard. However, the comparison of 150 analyses of samples of diverse lithologies, collected from a single core, reveals that these relationships are affected by sediment composition (presence of clays, salts, and the variable content of organic carbon). This results in an incremental error on the estimation of carbon content from LOI values that invalidates the use of LOI values as a quantitative method for estimating carbon content. Conversely, the general trends of LOI 550 and LOI 950 show a good correlation with carbon content (both organic and inorganic) allowing use of LOI as a qualitative test for carbon content. Similarly, in our case, LOI at 105°C (LOI 105 ) is a good qualitative proxy for the trends in gypsum content.

AbstraetDetailed mapping based on aerial photographs at various scales, analysis of morpho-sedimentary units, and radiocarbon dating of the prograding beach-ridge complex of Campo de Dalías (Almería) allow the differentiation of six prograding units, These are called: H¡, 7400-6000 cal BP; H2, 5400-4200 cal BP; H3, 4200-3000 cal BP; H4, 2700-1900 cal BP; Hs, 1900-1100 cal BP; and H6, 500 cal BP-Present. H-units are deposited during periods of high relative sea level and increased sediment input to the coast. They are bounded by large swales or erosional surfaces associated with lower sea levels and reduced input 01' sediment to the coast; these correspond to short periods 01' increased aridity inside the general arid trend recorded in the Westem Mediterranean since 5.4 ka. Changes in the flux 01' Atlantic superficial waters into the Mediterranean Sea, and relative strength of the W/SW winds account for the recorded oscillations of relative sea leve!.We deduce a decadal periodicity for the deposition of a beach ridge and the adjacent swale, and suggest that it is related to fluctuations of the North Atlantic Oscillation (NAO) index and to variations of solar activity. The duration of H-units shows a quasi-millennial periodicity punctuated by short (hundred years) episodes of reduced progradation or erosion representing events of increased aridity likely to be related to Bond's Holocene cold events.

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The coastal evolution of the El Abalario area (Huelva, southern Spain) during the Late Pleistocene and Holocene is reinterpreted after a refinement of the available geochronology by means of optically stimulated luminescence (OSL) dating. New data come from the analysis of soft sediment deformation, palaeosols, geomorphological mapping, and published seismic surveys on the onshore and offshore Gulf of Cadiz.The present structure of El Abalario dome resulted from the complex interaction of littoral-catchment processes and sealevel changes upon an emergent coastal plain, conditioned by the upwarping of the underlying Pliocene-Pleistocene prograding deltaic sequence. Upwarping is probably related to escape of over-pressurized fluids, accompanied by dewatering, prior to (?) and during OIS (Oxygen Isotopic Stage) 5. Continued upwarping produced the large NW-SE gravitational fault of Torre del Loro (TLF) in the southwestern flank of the dome, roughly parallel to the present coastline during OIS 5-OIS 4. The resulting escarpment favoured the accumulation of aeolian sand dunes (units U1, U2, and U3) from OIS 5 to early OIS 1. Unit U1 (OIS 5) ends upwards in a supersurface with a thick weathering profile that suggests moist and temperate climatic conditions. Unit U2 accumulated mainly during OIS 4 and OIS 3 with prevailing W/E winds. The supersurface between U2 and U3 records a part of OIS 2, with relative low sea level. Sedimentation of unit U3 took place during the Last Deglaciation (radiocarbon and OSL ages) with prevailing W/SW winds, under a temperate moist climate, that became more arid towards the top (Holocene). A major supersurface with an iron crust-like layer (SsFe) developed during the Holocene Climatic Optimum (OIS 1) under wetter and more temperate conditions than before, fossilizing the TLF. The supersurface is covered by younger aeolian dunes (U4, U5, U6, and U7) transported by W-SW winds since the Late Neolithic-Chalcolithic cultural period (~5.0 ky cal BP).

AbstraetSystematic mapping and morphosedimentary analysis of Fuerteventura and Lanzarote Islands supported by laboratory techniques (U-series mostly by TIMS, 14C analysis and allo-isoleucine measurements on biogenic carbonates from raised marine deposits, paleomagnetic and a few K/Ar measurements on vo\canic formations related to marine deposits) provide a basis for constraining the age of Late Cainozoic marine units. The most complete sequences of raised marine terraces are found at similar elevations in both islands. They inc\ude up to 12 marine terraces (Episodes) at elevations between O m and 70 m aboye mean sea level (asl). At least six terraces should be of Quaternary age, and more recent than 1.2 Myr. Throughout the whole marine sequence with the exception of the Holocene terrace, the warm fauna assemblage is characterized by the presence of Ostrea virleti, Nerita emiliana, and Strombus (S. cf. coronatus-S. cf. bubonius). However, there is a major change, highlighted by the disappearance of the first two species, below the 8-10 m terrace, that could possibly correspond to MIS 11. K-Ar measurements allow an estimate for mean uplift rate of 1.7 cm/ka during the last million years. The present elevation of the Last Interglacial deposits (about l and 2 m asl) shows discontinuous vertical movements with possibly a reverse trend since MIS 9 in eastern Canary Islands.

-The interaction between global (glacio-eustatic sea-level rise) and regional factors (oceanographic and tectonic) has controlled the evolution of coastline during the Holocene in Southem Iberia.At ca. 10,000 14C years BP a deceleration of relative sea-level rise took place both in the Atlantic and Mediterranean littorals, with a maximum transgression at 6450 14C years BP. In subsiding areas (present tidal flats) estuaries illustrate a clear marine influence recorded both in sediments and the fauna while in uplifting areas prograding spit-bar systems developed. Two phases of major progradation are distinguished in these systems: the first one between 6450 and 3000 14C years BP, with a sedimentary gap at ca. 4000 14C years BP; and the second one from 2750 14C years BP up to present, with an intervening gap between 1200 and 1050 14C years BP. These progradation phases develop during stillstands followed by relative sea-level fall, while the sedimentary gaps represent relative high sea level. In the Mediterranean areas, with a higher uplift rate, marine terraces almost coeval to those gaps occur.The most pronounced modifications in littoral dynamics occurred at between 3000 and 2750 14C years BP represented by changes in the direction of longshore drift and prevailing winds and in the predominance of progradation over aggradation processes.At ca. 1000 14C years BP the estuaries record a greater fluvial than marine influence, and at 500 years ago an extraordinary increase in coastal progradation took place in all littoral zones. The European Medieval Warm period is characterized, at least during its initial phase, by low pressure climate conditions, while during the Little Ice Age anticyclonic conditions gave rise to a strong coastal progradation.