# Preliminary Assessment of Quartz Sand Properties from Latvian Coastal Beaches for Potential Filtration Applications

## TL;DR

This study examines the properties of sand from four Latvian beaches to understand their potential for filtration and engineering use.

## Contribution

A multiproxy approach combining grain roundness, SEM textures, and XPS chemistry is used to identify sedimentary fingerprints in Latvian beach sands.

## Key findings

- Grain roundness and SEM textures differ significantly among four Latvian beach sites.
- XPS analysis reveals distinct surface chemistry linked to abrasion, biofilms, and fluvial input.
- Multi-proxy data identify unique sedimentary fingerprints for each coastal setting.

## Abstract

What are the main findings?
Grain roundness and SEM textures differ strongly among four Latvian beach sites.XPS reveals distinct surface chemistry linked to abrasion, biofilms and fluvial input.Multi-proxy data identify unique sedimentary fingerprints for each coastal setting.

Grain roundness and SEM textures differ strongly among four Latvian beach sites.

XPS reveals distinct surface chemistry linked to abrasion, biofilms and fluvial input.

Multi-proxy data identify unique sedimentary fingerprints for each coastal setting.

What are the implications of the main findings?
Surface textures and chemistry trace sediment pathways along the Baltic coast.Results improve provenance interpretation in mixed coastal–fluvial environments.Findings support assessment of natural sands for filtration and engineering use.

Surface textures and chemistry trace sediment pathways along the Baltic coast.

Results improve provenance interpretation in mixed coastal–fluvial environments.

Findings support assessment of natural sands for filtration and engineering use.

Understanding the environmental pathways and surface modification of beach sand grains is essential for reconstructing coastal dynamics and assessing the suitability of natural sands for engineering applications. This study applies a multiproxy approach—integrating grain roundness classification, SEM microtextural analysis, and XPS surface chemistry—to beach sediments from four coastal sectors of Latvia: Liepaja, Ventspils, Riga, and Salacgrīva. The results reveal clear spatial differences in grain maturity, abrasion signatures, biological imprinting, and nanoscale surface composition. Liepaja is characterised by sub-rounded to rounded grains with abundant percussion pits and abrasion surfaces, indicating prolonged high-energy wave reworking. Ventspils retains angular grains with fresh conchoidal fractures, reflecting rapid sediment renewal from glacial and coastal sources. Riga exhibits weak abrasion and hydrated particulate coatings typical of low-energy brackish environments. Salacgrīva displays strong fluvial influence, including persistent diatom and algal microtextural features and elevated oxygenated carbon and metal-associated XPS signals. These findings demonstrate strong coupling between grain-surface microtextures and surface chemistry and reveal distinct sedimentary fingerprints linked to environmental setting. The multiproxy framework presented here improves understanding of Baltic coastal sediment pathways and provides a preliminary basis for future evaluation of natural sands in filtration and other environmental engineering applications.