Quartz grain surface features from fluvial environments of northeastern Georgia

Quartz grains collected from northeastern Georgia streams display a distinct set of surface features. Included are irregularly shaped coalescing and non-coalescing impact pits and meandering ridge/oriented fracture patterns produced by grain collisions, irregularly shaped solution pits, branching to linear solution channels, and oriented triangular facets generated by chemical etching. Grains examined are from igneous and metamorphic terrains and should display features imprinted by chemical and/or mechanical processes occurring in streams and not those created by prior sedimentological/diagenetic regimes. Correlation coefficients indicate a fluvially derived origin for observed surface features. Samples from the North Oconee River show fair to weak correlations (+0.41 to +0.20) between surface feature abundance and distance of transport; those from the Soque River display little or no correlation between variables (+0.07 to -0.11). Great similarities exist between those features observed on grains from study area streams and those from beach and dune environments. Meandering ridge/oriented fractures and coalescing impact marks are present on grains from eolian environments as well as on grains from the stream environment. Numerous oriented triangular facets are seen on grains from littoral environments and also on grains from study area streams. This indicates that the processes which imprint surface features on quartz grains are not fully understood and that investigators should be wary of using these features by themselves as environmental indicators.