CLASTIC QUATERNARY SEDIMENTS OF THE AUGŠDAUGAVA SPILLWAY VALLEY AS NATURAL RESOURCES – GRAIN SIZE DISTRIBUTION AND MICROMORPHOLOGY OF QUARTZ GRAINS AS INDICATORS FOR DISTINGUISHING ALLUVIAL AND GLACIOFLUVIAL SAND DEPOSITS. ENVIRONMENT. TECHNOLOGY. RESOURCES. Proceedings of the International Scientific and Practical Conference, [S. l.], v. 1, p. 272–276, 2019. DOI: 10.17770/etr2019vol1.4094. Disponível em: https://archive-journals.rtu.lv/etr/article/view/4258.. Acesso em: 11 mar. 2026.