Differential Transport of Fall-Equivalent Sand Grains, Lake Ontario, New York
1985; Society for Sedimentary Geology; Volume: Vol. 55; Linguagem: Inglês
10.1306/212f867a-2b24-11d7-8648000102c1865d
ISSN1938-3681
AutoresC. Brian Trask, Bryce M. Hand,
Tópico(s)Coastal and Marine Dynamics
ResumoABSTRACT Fractions composed of grains having uniform fall velocity (equivalent to 2 quartz) were extracted from beach sands collected along the eastern end of Lake Ontario, New York. Heavy-liquid separations and point counts were performed on these fall-equivalent velocity splits to obtain relative abundances of hornblende, augite, hypersthene, garnet, magnetite, and quartz-density lights. Heavy minerals decrease in abundance in the direction of transport, and the degree to which any particular mineral lags behind another lighter mineral is a simple function of the mineral's effective-density ratio. Our results appear to confirm that heavy minerals are less transportable than fall-equivalent lights, an effect that may result from differential entrainability, transport within different zones of the beach, or both.
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