Daisy chain method applied to mapping the asthenosphere

The discovery of very rapid uplift rates under areas recently de-glaciated and the realization that such rapid uplift can stabilize ice sheets has generated interest in determining the properties of the asthenosphere.  The asthenosphere is also important to plate tectonics, and to the proper interpretation many important Earth observations.  The current approach to determining the properties of the asthenosphere is to calculate the observed rate of uplift in an area for a great many deglaciation and earth models, calculate the difference between the observed and calculated uplift rates and histories, and find the earth model (with error bars) that best matches the observations.  A faster, simpler, and in some ways better assessment method is to compute the isostatic adjustment response to a loading history consisting of linear segments.  This method determines the central response time from the dimensions of the load, the loading history, the lithosphere flexural rigidity (often not important), and the present rate of uplift.  The last can be easily measured today with GPS in INSAR.  Asthenosphere properties are indicated by the central response time so determined. The Daisy chain method will be described, evaluated against data and conventional modeling in northern Norway, and then applied to infer asthenosphere properties in a number recently-deglaciated continental localities.