Environmental Sensitivity of Submicroscopic Surface Textures on Quartz Sand Grains: A Statistical Evaluation

Baker, Harold

A statistical evaluation of the occurrence of selected surface textures on quartzsand grains from eolian and subaqueous environments was made to determine their environmental sensitivity. Samples conected at Padre Island, Texas, and the adjacent inlanddune fields were used to identify the limits of sensitivity on a local scale (i.e., beach, dune,etc.). In comparing means and standard deviations, only the lagoonal facies was found to bedistinctive. It could be identified easily by the abundance of chemically etched, orientedtriangular-shaped patterns. The other features characteristic of subaqueous or eolianprocesses are more or less equally distributed throughout the coastal area. Analysis of scatterplots and linear regression revealed weak trends in which subaqueous features are replacedby eolian features moving inland from the beach.Comparison of statistics for the samples from the Texas coastal region with statisticsfor samples from four interior deserts suggests that if over half of the grains in a samplehave chemically etched, oriented triangular-shaped patterns or mechanically formed V -shapedpits and straight or sJightly curved grooves and scratches, then a coastal province might bededuced. Irregular or polygonal cracks were present on over half of the desert grains examinedand were much less abundant on the grains from the coastal region. None of theother six features examined were statistically distinctive for environmental determinations.

Environmental Sensitivity of Submicroscopic Surface Textures on Quartz Sand Grains: A Statistical Evaluation

Series