CEPS Research

Mojave Desert

near Parker, Arizona:

(108k) Stabilized dunes (orange-yellow in this view) near the town of Parker, Arizona. False-color Landsat Thematic Mapper image (bands 5/3/1 are R/G/B) taken on 1/6/83. North is to the top. Agriculture on the flood plain of the Colorado River appears red (left). Dunes examined in the field (see below) are north of highway at lower right.

(77k) Dual-field spectroradiometer in use on a stabilized dune near Parker, Arizona. Reflectances of both the target (sand) and a reference standard (white square) are measured simultaneously and transferred to a lap-top computer out of view to the lower right. Photo taken 5/21/95.

(108k) Vertical view of sand on stabilized dune near Parker, Arizona. Photo taken 5/21/95.

(36k) Reflectance spectra of sand on stabilized dune near Parker, Arizona. Reflectance is shown as a percentage of the reflectance from the standard. Water vapor causes strong absorption at 1400, 1900 and 2600 angstroms.

Rice Valley, California:

(102 k) Stabilized dunes in the Rice Valley of California. False-color SPOT image (bands 3/2/1 are R/G/B) taken on 9/25/93. North is to the top. Dune orientations indicate sand emplacement from the west. Agriculture on the flood plain of the Colorado River appears red (right).

(114k) Classified image of Landsat Thematic Mapper data for Rice Valley in California. Landsat data were obtained on 9/26/86. Red corresponds to stabilized dunes, yellow corresponds to interdune, and blue corresponds to active sand areas. Stabilized dunes have sand similar to dunes near Parker, Arizona. Interdune surface is shown in photos below.

(91k) Stabilized dunes (linear features) in the Rice Valley of California. Portion of a false-color Landsat Thematic Mapper image (bands 5/3/1 are R/G/B) taken on 9/26/86.

(116k) Dual-field spectroradiometer in use on an interdune area in the Rice Valley of California (yellow in classified image). Reflectances of both the target (sand/gravel) and a reference standard (white square) are measured simultaneously and transferred to a lap-top computer out of view at bottom. Photo taken 5/24/95.

(131k) Vertical view of interdune surface in the Rice Valley of California. Gravel pebbles consist of quartz-rich fragments of rocks from the surrounding hills. Photo taken 5/24/95.

(38k) Reflectance spectra of interdune in the Rice Valley of California. Reflectance is shown as a percentage of the reflectance from the standard. Water vapor causes strong absorption at 1400, 1900 and 2600 angstroms. Overall spectra is similar to sand spectra in #4, but generally of lesser magnitude at all wavelengths.

Next Page-Cadiz Valley, California

CEPS Research Page

Revised: April 2, 2001 (jh) ©1994-2001 National Air and Space Museum