ESR (electron spin resonance) can date sites that span the whole Paleolithic, but requires accurate sedimentary dose rates, especially in caves where the internal and cosmic dose rates can approach 0 mGy/yr. This study examines the sedimentary radioactivity in the upper layers at Golema Pešt, North Macedonia. Reaching > 5.5 m deep, > 21 flatly lying, silty-sandy matrix-supported gravel layers with éboulis clasts fill the cave. In Sondage 2, Layers 0–5 contained many hearths and yielded thousands of bones and teeth, many from ungulates. In Layers 2-5a sat thousands of lithics and small tools, many made on tiny quartz crystals. Layers 2c-6 have Mousterian assemblages with denticulates, notched tools, Levallois cores and flakes. To measure the volumetrically averaged sedimentary dose rates for ungulate teeth dated by ESR from Sondage 2, 66 sediment samples were analyzed by NAA. Adding éboulis, calcined bone, and charcoal associated with the hearths lowered the sedimentary dose rates or left them unchanged. In Layer 2 at 198 cm below the cave datum, the Campanian Ignimbrite (CI) cryptotephra occurred, where it caused abnormally high sedimentary U, Th, and K concentrations and dose rates. Since the CI tephra lay 28–30 cm above AT77, a tooth dated from Layer 3, using time- and volumetrically averaging increased AT77’s sedimentary dose rate by 32%, and dropped its calculated age by 25%. Analyzing the sedimentary compositions at every 2 cm in Layers 0–2 yielded a highly detailed stratigraphy that reduced the uncertainty in the sedimentary dose rates and the ESR ages, but more detailed geochemical analyses must be completed within the lower layers in Sondage 2.

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The aim of the present study was to accurately assess the changes in the degree of instantaneous pollution of natural river. In this paper, a pollutant diffusion model (LBM-CA) for vegetation open channel is constructed. This model consists partly of Cellular Automaton (CA), and the main task of this part is to simulate the pollutant diffusion. Flow influence coefficient is introduced into Cellular Automata to express the influence of vegetation on pollutant diffusion. In order to obtain the flow influence coefficients for each cellular, Lattice Boltzmann Method (LBM) is introduced in the LBM-CA model to simulate the flow in vegetation open channels. The results show that the LBM-CA model has high accuracy. The simulation results show that the existence of vegetation will lead to the accumulation of pollutants and prolong the residence time of pollutants in the vegetation area. The pollutant limits are embedded in the LBM-CA model to predict the pollution level of the basin at a specific time. LBM-CA model provides a method for simulating pollutants diffusion in natural rivers.