A Reappraisal of Global Heat Flow Data

in an attempt to understand the characteristic features of global thermal field. The initial effort was directed at verifying the overall structure, quality and internal consistency of the database. Thus the present system of intercalating tables and references was transformed into a coherent and organized database that is amenable for scientific analysis. Subsequently, the format employed for geographic coordinates has been replaced by a consistent decimal degree system that allows implementation of automatic computer based processing facilities. At present, a detailed verification of the entire data set is being carried out to minimize problems arising from typographic errors.<br>The restructured database has been used in calculating mean values of heat flow for a regular grid system composed of 50 x 50 surface area elements. Spherical harmonic analysis of this system of regular grid values have allowed calculation of a new set of fully normalized Legendre coefficients (169 coefficients for a 12 degree expansion). Maps based on the new set of coefficients have lead to identification of several new features in the conductive component of global heat flow. Comparison with results of previous studies indicates discrepancies in several regions. There are indications that some of the major high heat flow anomalies identified in previous studies are artifacts of interpolation procedures. The reason appears to be widespread use of synthetic values instead of experimental data.