Southeast Tibet Mountains
This spaceborne radar image covers a rugged mountainous area of southeast Tibet, about 90 kilometers (56 miles) east of the city of Lhasa. In the lower right corner is a wide valley of the Lhasa River, which is populated with Tibetan farmers and yak herders, and includes the village of Menba. Mountains in this area reach about 5800 meters (19,000) feet above sea level, while the valley floors lie about 4300 meters (14,000 feet) above sea level. The Lhasa River is part of the Brahmaputra River system, one of the larger rivers in southeast Asia eroding the Tibetan Plateau. The rugged relief in this area reflects the recent erosion of this part of the Plateau. Most of the rocks exposed outside of the river valleys are granites, which have a brown-orange color on the image. In the upper left center of the image and in a few other patches, there are some older sedimentary and volcanic rocks that appear more bluish in the radar image. Geologists are using radar images like this one to map the distribution of different rock types and try to understand the history of the formation and erosion of the Tibetan Plateau. This image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) on April 10, 1994, on board the space shuttle Endeavour. North is toward the upper left. The image is 49.8 kilometers by 33.6 kilometers (30.9 miles by 20.8 miles) and is centered at 30.2 degrees north latitude, 92.3 degrees east longitude. The colors assigned to the radar frequencies and polarizations are as follows: red is L- band, horizontally transmitted, vertically received; green is C-band, horizontally transmitted, vertically received; and blue is the ratio of C-band to L-band, horizontally transmitted and received. SIR-C/X-SAR, a joint mission of the German, Italian and United States space agencies, is part of NASA’s Earth Science Enterprise.