Sea level and clima te changes archived in various coastal environments during the last part of the last glacial and present interglacial periods are investigated by interpolating available geomorphology, sedimentology, palaeontology and geochronology data. The coastal response to these changes depended on the environment and geographic location. Changes of sea level during the rising, transgressive phase are well recorded in the sedimentary filling of the estuaries, whereas during the phase of highstand they are best recorded in beach-barrier environments. The postglacial rise of sea level took place in two phases: a rapid rise until 6500 cal BP, and a second phase of near stability with minor oscillations of metric magnitude. Regarding climate changes, there is no record of changing temperatures in the coastal zones of southern Spain, although there is in precipitation and wind intensityjvelocity. After 7-5 cal ka BP, the general climatic trend towards aridity was punctuated by several short-lived (centennial) episodes of increased aridity that occurred with a millennial cycle, often coincident with Bond cool events and, in sorne cases, with decreases of sea surface temperatures. The absence of human in ter ventio n in vegetation composition until 2000 BP suggests that most environmental coastal shifts were climatically driven,
Many on-shore studies focused on high energy marine events occurred in the Gulf of Cadiz have been published since the 1990s. Most of the findings came from sedimentary, palaeontological and geomor phological records on estuaries, marshes, beach-barriers (spit-bars), and some coastal lowlands. Recent off-shore investigations in SW Iberia considered turbidite deposits as a proxy to recognise palae oearthquakes in this zone. The comparison of datasets from both on-shore and off-shore records indicate that at least five tsunami events generated by strong earthquakes affected this area during the last 7000 years, previous to the more recent and well-documented 1755 AD Lisbon earthquake tsunami event. The catalogue of Holocene palaeotsunami presented here is supported by geological and geomorphological evidences, but also for archaeoseismic and palaeoseismic evidence and written reports for the more recent events occurred during historical times. The recurrence interval for these catastrophic events can be bracketed between 1200 and 1500 years.
SlUlll ll ary.Sedimentological and palaeoecological observations, accompanied by archaeological determinations and absolute dating, have been carried out on a recent beach-barrier system succes sion located 20 km south of Siracusa, south-eastern Ionian coast of Sicily (Italy) . These deposits fi ll the back edge of a ria incised within Miocene limestones and are composed of three main stratal units characterized by distinct sedimentological fe atures. The two lower units, fo rmed by cross bedded sands and laminated days, recorded the development of a small confined beach-barrier depo sitional system, influenced by fr equent high-energy events. The upper unit, represented by chaotic coarser sediments, can be attributed to a destructive marine high-energy event. The physical prop erties of the composing stratal units and the morphological setting of the study area allowed us to reconstruct a suite of storm-and tsunami-related marine depositional processes that might have occurred in recent times along this area of elevated seismicity. In particular, absolute dating and archaeological determinations allow correlating the upper unit to a tsunami wave triggered by the 1693 AD catastrophic earthquake. The same depositional mechanism can also account for some of the coarse levels occurring into the underlying stratal units.
The Quaternary sedimentary record of Sal Island includes marine and related aeolian and alluvial fan deposits. The substratum of the island is volcanic, with ages between 25 and 0.6 Ma. Quaternary marine units generally occur as raised marine terraces forming a broad staircase between elevations of 55-60 m and present sea level. Terraces include a basal conglomerate overlaid by calcarenite; both host corals, algae and molluscs.A chronostratigraphic framework for the Middle Pleistocene to Holocene units has been generated based on a geomorphologic map of the Quaternary landforms and associated deposits and morphosedimentary analysis, with support of laboratory dating: U-series by TIMS in corals, 14 C analyses, palaeomagnetic measurements, and K/Ar ages from other literature. U-series dating of corals from marine terraces provides benchmarks for the Last Interglacial (Oxygen Isotope Substage 5e) and Holocene deposits. The present elevation of the marine terraces and their staircase arrangement suggest a change in vertical movement trend around 330 ka from an uplift to either subsidence or stabilization. r
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