A quad-pol radar scattering model for use in remote sensing of lava flow morphology

doi:10.1016/0034-4257(89)90064-3

Remote Sensing of Environment

Volume 30, Issue 3, December 1989, Pages 227-237

https://doi.org/10.1016/0034-4257(89)90064-3 Get rights and content

Abstract

Mapping of spatial variations in surface roughness over large regions is required to understand the nature of volcanic terrains. An invertible scattering model for quad-polarization radar data is presented to assist in the remote-sensing analysis of lava flow surface morphology. This model permits separation of the polarized part of the radar echo into quasispecular, dihedral, and small-perturbation scattering components, based on an assumed surface dielectric constant. Tests are presented for a quad-pol scene of Craters of the Moon National Monument in Idaho, where there are a number of basaltic lava flows of differing surface morphology. Comparison of calculated model components with the observed morphology of the lava flows suggests that this technique may be useful for the remote description of changes in surface roughness. The scattering mechanisms chosen to represent the polarizing behavior of the real surface display correlations which indicate that they are sensitive to the expected scales of roughness.

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Citation Excerpt :
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^∗∗: Special thanks are due to Duncan Munro, for incaluable help in collecting the field topographic data. Thanks also to Howard Zebker and Jakob van Zyl for many discussions on the interpretation ofquad-pol radar data, and to Gerry Schaber and Walt Brown for valuable guidance in the collection of topographic measurements and their comparison with radar backscatter. Helpful reviews by Lisa Gaddis, Paul Lucey, Duncan Munro, Scott Rowland, and four anonymous reviewers are greatfully acknowledged. A grant from NASA's Geology Program (NAGW-1162) supported a part of this research, wich forms part of the PhD research of Bruce Campbell. This is Hawaii Institute of Geophysics contribution 2274.

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A quad-pol radar scattering model for use in remote sensing of lava flow morphology

Abstract

Remote Sens. Environ.

J. Volcanol. Geotherm. Res.

J. Volcanol. Geotherm. Res.

Remote Sens. Environ.

Scattering from surfaces with different roughness scales: Analysis and interpretation

Ohio State Univ. Electroscience Lab. Report #1388-26

Effects of variation in look angle and wavelength in radar images of volcanic and aeolian terrains, or Now you see it, now you don't

Int. J. Remote Sen.

What are the best radar wavelengths, incidence angles, and polarizations for discrimination among lava flows and sedimentary rocks? A statistical approach

IEEE Trans. Geosci. Remote Sens.

Principles of Optics

Radar polarimetry: analysis tools and applications