I’m studying the oxygen isotope composition of central Texas rain water, cave drip water, and Travertine calcite. The oxygen isotope composition of precipitation varies due to a number of factors such as the temperature at the time of a storm, the amount of rain that fell, the moisture source of the storm, and the location of the storm. When rain falls over karstic areas, some of that rain water filters through the unsaturated zone and where it precipitates calcite in the form of speleothems. This drip water and the calcite precipitating from it can preserve the oxygen isotope signal of the rainfall. Thus, speleothems could be used to glean information about paleoclimate.
My research investigates the first part of this problem: I want to know 1) How the oxygen isotope
composition of precipitation in central Texas varies based on weather pattern and 2) In what ways the oxygen isotope composition of cave drip waters preserves the composition of rain water. I’m also looking at a travertine calcite sample that may have preserved the oxygen isotope signal a tropical storm event that came through Austin in 1998.