Sand and aggregate resources Vaiusu bay, Apia, Western Samoa / Robert Smith
To assess the sand and gravel resources in Vaiusu Bay mapping of bathymetry and drilling of 60 jetprobe holes to a maximum penetration depth of 5.0 metres was completed. From the jetprobing data a subsurface of impermeable reef pavement was encounted in the eastern portion of the survey area. This in part has controlled the direction of where the existing dredging has taken place. Dry sieve analysis shows the sediments to be classified into three textural sub-groups, gravel, sandy gravel and gravelly sand. Examination of the composition indicates a dominance of coral rubble and detritus, shell fragments and whole gastropods, echinoid spines and some Halimeda present. Foraminiferal faunas usually a significant component of beach sands were noticeably few. Calculated volume of aggregate in the resource area is 3 million m3 for water depths ranging between 0 and 3 metres.
