Premium
The formation and significance of irregularly shaped quartz grains in till
Author(s) -
MAY RONALD W.
Publication year - 1980
Publication title -
sedimentology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.494
H-Index - 108
eISSN - 1365-3091
pISSN - 0037-0746
DOI - 10.1111/j.1365-3091.1980.tb01182.x
Subject(s) - meltwater , geology , terrigenous sediment , quartz , mineralogy , evaporation , snow , groundwater , fracture (geology) , geomorphology , maturity (psychological) , sediment , geochemistry , geotechnical engineering , psychology , paleontology , developmental psychology , physics , thermodynamics
Thin sections and scanning electron microscopy of quartz sand grains from till show clearly that a number of grains have been modified in place. The irregular grains result from the action of circulating alkaline groundwater, episodically concentrated by evaporation on fracture surfaces within grains and on concave surfaces produced by fracture during glacial transport. Evaporation increases the pH of the pore water and localizes its effect in small pores with a high capillary potential. Subsequent dilution by rainwater or snow meltwater flushes the system so that evaporation can repeat the process again. Solution rounding in terrigenous sediments has a number of ramifications for any interpretation based on textural maturity of the sediment.