The palynological investigation of core TM (27.7 m long) taken in a dried out lagoon reveals both Holocene vegetation history in the north-eastern foothills of the Alborz Mountains and past water level changes of the Caspian Sea (CS).The delay in woodland expansion at the beginning of the Holocene, which is typical of eastern Turkey, the Iranian plateau and recorded in the CS south basin, is only weakly felt as the region is close to glacial refugia of trees.The succession of the main trees out of their refugia has been established as deciduous Quercus, Carpinus betulus, Parrotia persica, and Fagus orientalis-Pterocarya fraxinifolia, presenting therefore close affinities to south European interglacials of the Early Pleistocene. This suggests a similarity in climate.A Pterocarya decline is observed after AD 495. The studied region is close to the easternmost tree distribution; this could explain why it has been affected earlier than elsewhere in the northern Alborz and the Caucasus. In addition human activities during the Sasanian Empire and the subsequent drying of the climate contributed to weakening the spread of this tree.A maximal sea level occurs in the first part of the Holocene from 10.6 to 7.2 cal. ka. It is suggested that the CS levels were significantly influenced by the monsoon precipitations over the western Himalayas (via the Uzboy inflow). This is followed by low levels from 7.2 to 3.5 cal. ka with a minimum at 3.9 cal. ka.The Neocaspian period should be considered a biozone rather than a chronozone, as the environmental conditions reconstructed from dinocyst assemblages are different in shallow shelf waters and in the deep basins
Numerical modeling on a geological timescale is a rapidly expanding tool to investigate controls on formation of the stratigraphic record. Modeling enables us to test existing ideas, but verification of model results is commonly difficult. Many models are based on geometric or diffusion rules, yet neither type of model has much relevance with actual processes that control sedimentary systems. Here we describe a process-response approach to model the evolution and stratigraphy of wave-dominated coastal systems in two dimensions, based on simple approximations of cross-shore erosion and sedimentation. Separating erosion and deposition functions enables us to simulate coastal evolution, stratigraphy, erosion surfaces, and transport of multiple-grain-size classes. The simulated stratigraphic record contains detailed information on grain size and stratal geometry. We calibrated the model with data sets on coastal transgression in the Caspian Sea, Dagestan, and on grain-size distributions at the island of Terschelling, The Netherlands. Furthermore, hypothetical examples are presented to show the effect of changes in sea level and sediment supply, substrate slope, and sediment size distribution. These tests show that the model is capable of reproducing widely accepted conceptual models of coastal evolution on geological timescales (progradation, aggradation, and various modes of retrogradation).