Abstract:
It is shown that glauconite was mainly formed under diagenetic conditions in terrigenous–clayey rocks (Rausven Unit) of the Lower Cambrian Virbalis Formation in western Lithuania. This was preceded by bioturbation at some levels of geological column and local short-term reworking at other levels. Different forms of glauconite and its interrelation with ambient minerals in diagenesis and epigenesis are considered. A two-phase micaceous (glauconite–illite) composition of globules has been revealed and crystallochemical characteristics of each phase is presented.