(550b) Spatial Statistics: Revisiting Our Definitions Of Well Mixed

Three main themes have evolved in the literature surrounding blend time, or definitions of well mixed. The first theme is around the reduction in variance at one or a few points in the flow.  We include the RTD and Dankwerts original definitions of segregation in this theme.  The second theme involves the percent of the total volume which is well mixed over time, which provides a more complete picture of the mixing, but requires a more complete data set.  The third theme is around measures of system dynamics, or chaotic mixing theory.  We consider these three themes, and place them in the context of spatial statistics and segregation studies in other fields such as population ecology, racial segregation, ore sampling, and forest management.  An attempt is made to rigorously define the question of "well mixed" and identify appropriate sampling strategies and criteria for analysis, providing a more rigorous definition of mixing, sampling requirements, and expected errors in measurement.