Jarosyty w serii iłów poznańskich

Abstract

JAROSITES IN THE POZNAŃ DAY SERIES Summary Eight sections of clays with jarosites have been found to occur in the Neogene deposits of the Poznań series. The jarosites make, together with gypsums, the body of thin veinlets or incrustations on clay fissures. They occur within near-surface zones, to a depth of about 7 m. Chemical analyses (Table I), DTA determinations (Fig. 1) and X-ray analyses (Table Il, Fig. 2) have been made of four jarosite samples. The jarosites here examined represent potassium, sodium and sodium-potassium jarosites (Table III). Along with the secondary grypsum the jarosites are minerals that determine the Quaternary weathering zones of the Neogene clays with iron sulphides.