Lower Tertiary stratigraphy in east-central MS shows cyclic sedimentation. Normal cycle consists of basal transgressive sand member, median clay or shale member of inundated phase, and upper regressive silt or fine sand member. Second cycle of the Wilcox, Ackerman formation, is most conspicuously developed cycle in lower Tertiary. Its basal sand, here named the Noxubee sand, exhibits evidence of orogenic developments in region by its coarse grain, sporadic presence of pebbles, cobbles, and boulders (up to 905 lbs) of quartz and quartzite, local concentration of large muscovite flakes, its thickness (up to 475 ft in subsurface of Jasper Co), and its wide-spread lateral extent. Age of Noxubee is Eocene.

Source: GNU records (USGS DDS-6; Reston GNULEX).