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Документ Heavy-mineral concentrations as proxies of high-energy events along sandy coasts(Astroprint, 2006) Buynevich, I. V.; Larchenkov, Yevhenii P.; Oakley, B. A.Sediment-rich coastal sequences have the potential of preserving long-term records of regional-scale erosional events. Among the most diagnostic features of erosion are steep berm and dune scarps, regional unconformities (discontinuities), layers of coarse sediment or shell hash, as well as extensive accumulations of heavy minerals (magnetite, ilmenite, garnet, zircon, hornblende, etc.). These heavy mineral concentrations (HMCs) are found in many parts of the world and occur in thin layers or thick placer deposits (Fig. 1A). Their formation is due primarily to selective density sorting during the waning stages of storms (Komar and Wang, 1984; Peterson et al., 1986; Kurian et al., 2001). The HMCs can therefore be used as proxies for high-energy events along sandy coastal regions, and have been attributed to storm or tsunami-induced erosion in a number of studies (Smith and Jackson, 1990; Nichol, 2002; Buynevich et al., 2004; Dougherty et al., 2004). Substantial contrast in electromagnetic properties between sands enriched in ferromagnesian heavy minerals and quartz-rich background sediments is responsible for the sharp nature of subsurface reflections (Meyers et al., 1996; Buynevich et al., 2004) making HMCs some of the most prominent horizons in ground-penetrating radar (GPR) profiles (Fig. 1B). By combining high-resolution geophysics for mapping subsurface erosional indicators with radiocarbon or optical dating of individual erosional horizons, it is possible to reconstruct the long-term history of coastal hazards in various parts of the world.Документ Morphodynamics and geological legacy of berm scarps along non-tidal (Ukraine) and microtidal (The Bahamas) coasts(Одеський національний університет імені І. І. Мечникова, 2014) Buynevich, I. V.; Savarese, M.; Kadurin, Serhii V.; Larchenkov, E. P.; Park Boush, L. E.; Curran, H. A.; Beal, I. A.; Буйневич, И. В.; Саварис, М.; Кадурин, Сергей Владимирович; Ларченков, Е. П.; Парк Буш, Л. Е.; Карран, Г. А.; Бил, И. А.; Буйнєвич, І. В.; Саваріс, М.; Кадурін, Сергій Володимирович; Ларченков, Є. П.; Біл, І. А.Berm scarps are erosional features characteristic of all coastal accumulation forms. Their profiles range from steep to overhanging (ψ>90) and evolve through slope adjustment and burial by swash and aeolian accretion. Examples from the mixed siliciclastic-bioclastic beaches of the non-tidal Black Sea coast of Ukraine and the microtidal oolitic-bioclastic carbonate islands of the Bahama Archipelago demonstrate a wide range of scarp morphologies. Truncations of berm strata and density lag at the scarp base accentuate their recognition in the field and in geophysical (georadar) records. Although ephemeral as surface features, berm scarps may act as nucleation sites for aeolian aggradation, thereby generating continuous coast-parallel dune ridges. Accumulation of organic debris promotes colonization of incipient foredunes by plants and provides chronological control of erosional events. Therefore, paleo-berm scarps serve as important geological indicators of past storm activity and aid in constraining sea-level position.