By studying water chemistry differences within the lake we learn how algal blooms, increases in precipitation and nutrient concentrations eventually affect the sediment chemistry. This information guides our interpretations of past changes. For instance, our Bear Lake cores show that, between 8000 and 6500 years ago, calcite replaced aragonite as the major mineral being deposited in the lake. This 1500-year-long decrease in salinity was probably caused by renewed flow of the Bear River into Bear Lake. For more information on this and other salinity events at Bear Lake, check out the carbon results page.

Water samples at specific depths are collected using van Dorn or Kemmerer-style bottles. The bottle is an open tube with spring-loaded end caps. The bottle is lowered to a particular depth and sloshed around gently (to fill the tube with water from that depth). Then a weight, called a messenger, is sent down the line holding the tube. The weight hits a spring mechanism, allowing the end caps to spring shut.