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This paper studies the Late Holocene benthic foraminifera from a continuous core extracted in the Doñana National Park (SW Spain). In this core, the foraminiferal assemblages confirm the Late Holocene lagoon (historically so-called Lacus Ligustinus) during the Roman period, about 2000 years ago. The more open, deepest areas of this lagoon were dominated by Ammonia tepida and Elphidium spp., while Haynesina germanica was the most representative species of the shallow, more restricted zones. The vertical variations of these assemblages, together with associated sedimentological and macrofaunal changes, allow recognizing three high-energy events (HEE) between 500 BCE and 500 CE, which also left an extensive sedimentary record in nearby coastal areas: two tsunamis (HEE-1 and HEE-3) and a storminess period (HEE-2). [ABSTRACT FROM AUTHOR]

Landscape dynamics in the periglacial belt of a high mountain Mediterranean environment is a process of rapid evolution but complex reconstruction. Following this purpose, in this paper we discuss data from two sources concerning the past evolution of the present-day periglacial environment in the Sierra Nevada (southern Iberian Peninsula): mountain lake sediments and documentary sources. La Mosca lake sedimentary record provides information about the palaeocological evolution in the Mulhacén cirque over the last three millennia, while documentary sources enable us to reconstruct the landscape evolution in the high lands of this massif over the last eight centuries. During the late Holocene cold and wet phases have favoured the activity of geomorphic processes, with ephemeral development of glaciers in the highest northern cirques, abundance of late-lying snow patches and a decrease of the vegetation cover in the highest catchments. By contrast, warm periods have been more conducive to geomorphic stability, with an extension of the vegetation grass cover, but without glaciers and with a lower density of snow patches in summer. The comparison of the palaeocological evolution and associated palaeoclimatic conditions in the Sierra Nevada with other regional proxies shows evidence of the moderate sensitivity of the geomorphological processes occurring in the massif during the late Holocene with respect to the climate variability prevailing in the Iberian Peninsula and neighbouring areas. According to lake sedimentary records, the ‘Little Ice Age’ has been the coldest period during the late Holocene. Historical sources suggest a temperature increase of 0.93°C since the middle of the 19th century. [ABSTRACT FROM AUTHOR]

Abstract: The Guadalquivir estuary is one of the most important in Europe. It is isolated from the sea by two important littoral spits (Doñana and La Algaida). Its sedimentary filling occurred as a result of deltaic contributions of the Guadalquivir River, giving rise to marshes primarily composed of mud deposits, among which a succession of sandy and shelly ridges can be found. The aim of this paper is to explain the genesis and evolution of these sandy and shelly ridges clarifying what types of ridges are found and their spatial distribution, identifying the processes responsible for their formation. These ridges extend in the form of long strands along the estuary, influencing its evolution during the Late Holocene. The geomorphologic and lithostratigraphic features of these ridges allow them to be defined as transgressive cheniers, regressive cheniers and laterally accreted ridges (spits), as components of the Guadalquivir estuary chenier plain complex. This chenier plain has the peculiarity of developing on a semi-enclosed shoreline, contrary to other chenier plains in the world, which develop on open coasts. In the Guadalquivir estuary the chenier plain formation is related to two relatively higher sea level (4200–2800 yr BP and 1400–1000 yr BP) during which high energy events occur (storms and tsunamis), that transgressed the large littoral spits. The Carrizosa (∼4000 yr BP) and Vetalengua (∼1400–1300 yr BP) spits have been formed across the inlet, and prograded landwards of the estuary. From here, several sequences of cheniers (mainly transgressive cheniers) associated with these events were formed. These cheniers form two groups: Las Nuevas (∼1100–1000 yr BP) and Marilópez (∼3000 yr BP), composed mainly of shells and shell fragments. These cheniers were constructed by waves which reworked the shells above estuarine levees, and led to their intense landward migration, thus explaining the peculiar, high inland position of the cheniers. [Copyright &y& Elsevier]

In recent decades, numerous studies have focused on the paleoenvironmental reconstruction of coastal areas, with special emphasis on the detection of tsunami layers. These multidisciplinary investigations usually do not study the mineralogy of the environment as well as the underlying or overlying layers.This paper analyzes the whole-rock mineralogy and clay minerals contained in seven short cores obtained in the Doñana National Park (SW Spain) and deposited during the 5.000–1.500 cal. yr BP interval.The main purpose is to deduce the paleoenvironments from which the sedimentary facies present in them were formed and an approximation to the transport mechanisms involved in their formation. Results of X-ray diffraction analysis indicate that the main minerals are phyllosilicates, quartz and calcite, with smectites and illite being the most abundant phyllosilicates. According to the whole-rock mineralogy and additional statistical procedures (correlation, cluster analysis), the main source of quartz is the erosion of Doñana spit, while the Guadalquivir river, its tributaries and the old lagoon have contributed mainly with smectite-rich phyllosilicates. On the contrary, waves, tides and high-energy events introduced illite and bioclasts in an old lagoon from the nearby shallow marine sectors. Consequently, the mineralogical analysis is revealed as an interesting tool for palaeoenvironmental reconstruction in this area, since it varies between different sedimentary environments. In addition, the combined study of whole-rock and clay mineralogy detects the tsunami layers and the provenance of their sediments in the studied cores. Unlabelled Image • The mineralogy is a powerful tool to reconstruct sedimentary sources. • In the Roman Lacus Ligustinus, phyllosilicates and smectites were supplied by the Guadalquivir River. • The mineralogy of the outer lagoonal area was controlled by the Doñana spit. • High-energy events caused the introduction of bioclastic quartz-rich sands. • Illite was introduced from the adjacent shelf to the innermost lagoonal zones. [ABSTRACT FROM AUTHOR]