Growth and early diagenetic changes in artificial gypsum crystals grown within bentonite muds and gels
Experiments designed to simulate muddy environments failed to nucleate anhydrite or cause replacement of initially formed gypsum crystals by anhydrite during five months at temperatures to 80°C and with pore solutions containing as much as 20 percent sodium chloride. Gypsum and bassanite (at higher temperatures and salinities) were the only species produced. In addition, gypsum crystals experimentally grown for several months in Wyoming bentonite gels and pastes and in the presence of dissolved monovalent salts underwent major habit changes. The habit produced by these early diagenetic changes is characteristic of many natural crystals found in saline sediments and probably is diagnostic of evaporite sedimentation.