Lithostatistical variability of beach gravels along the Polish coast of Baltic Sea: The Pogorzelica–Dziwnów dataset (363.0–391.4 km)

Abstract

The data presented in the article consist of petrographic types and grain shape parameters of beach gravels collected along the Pogorzelica–Dziwnów coast section (363.0 to 391.4 km of the coastline), southern Baltic Sea, Poland. Representative gravels with the diameter of 2-5 cm were sampled at 0.25 km intervals, in the middle part of the beach. The contribution of mechanically high resistant crystalline components (igneous and metamorphic rocks: granites and gneisses) and low resistant (sedimentary rocks: limestones, sandstones, and shales) has been presented. The Cailleaux and Zingg grain shape parameters were estimated taking laboratory measurements ( 3D -axis dimensions, flatness/roundness indices). The calculations have been provided based on the gravels weight and quantity. The obtained grain shape parameters depend on factors such as resistance to mechanical destruction or increased chemical weathering, being evidenced by several indices, such as the proportions between discoidal and ellipsoidal grains, or amount of spindle-shaped gravels. The calculated indices may serve as potential indicators of coastal lithodynamics, including intensity of sediment redeposition or mechanical reworking of the beach.