Data was collected by Jeffrey Schmok in November 1995 in order to prepare the Golder report on the bathymetry of Lakes Hoare, Fryxell, and Bonney. A 0.0 m contour is based on a shoreline survey of the frozen moat, and therefore is closer to piezometric water level than to top surface of floating permanent ice. Deeper contours are based on piezometric water level. Thus volume calculations within the ice cover represent volumes of liquid water as if the ice was melted.
Third order polynomial equations were fit to the area vs. depth data both from Schmok's report and from the digitized map data, using SigmaPlot's curve fitting routine. However, since the contour data are already a "best-fit" of measured depth data, and contour intervals are relatively small, it was decided to linearly interpolate the depth:area relationships for depths between the measured depth contours, at 0.5m intervals. Volume was calculated for each 0.5m increment as a truncated cone
(V=(h/3)*(A1+A2+sqrt(A1*A2)).
