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Quade, J. G.

Publications and source records attributed to Quade, J. G..

30 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Microwave emission from geological materials - Observations of interference effects.

Microwave radiometric field observations were conducted at wavelengths of 21, 2.8, and 0.95 cm to determine the microwave penetration depth of a number of sands and gravels as a function of particle size and moisture content. Observations of a reflecting plate covered with varying thicknesses of test material exhibit a pronounced oscillatory behavior that is consistent with established electromagnetic theory for plane-parallel layered mediums. Utilization of this interference effect is proposed as a microwave radiometric technique for determining the bulk electrical properties of geologic materials, snow, ice, and other materials readily adapted to layering experiments.

Blinn, J. C., III↗
NASA NTRS1972

Microwave properties of geological materials: Studies of penetration depth and moisture effects

Summarized are the results of two of a series of controlled experiments performed during the summer of 1970. The first series of experiments to determine penetration depth showed the value of having a modeled response and data reduced in real time for examination in the field. The results suggest a radiometric method for measuring the microwave properties of materials in bulk and are applicable to studies of sea ice and other naturally layered media. The sensitivity of the microwave emission to changes in moisture content has inspired a number of airborne and ground based investigations. Although the effect is dominent under certain conditions, the complicating factors of soil type, roughness, vegetation, etc. seem to govern the conclusions regarding its application at this time.

Blinn, J. C., III↗