The Davenport Ranges of central Australia have been inferred to be among
the oldest persisting landforms on Earth, founded on the belief that the
interior of Australia has been tectonically stable for at least 700
million years. New rock age dating techniques indicate that substantial
erosion has probably occurred over that time period and that the landforms
are not nearly that old, but landscape evolution certainly occurs much
slower here (at least now) than is typical across Earth's surface.
Regardless of their antiquity, the Davenport Ranges exhibit a striking
landform pattern as shown in this display of elevation data from the
Shuttle Radar Topography Mission (SRTM). Quartzites and other erosion
resistant strata form ridges within anticlinal (arched up) and synclinal
(arched down) ovals and zigzags. These structures, if not the landforms,
likely date back at least hundreds of millions of years, to a time when
tectonic forces were active. Maximum local relief is only about 60 meters
(about 200 feet), which is enough to contrast greatly with the extremely
low relief surrounding terrain.
Two visualization methods were combined to produce this image: shading
and color coding of topographic height. The shade image was derived by
computing topographic slope in the northeast-southwest (image top to
bottom) direction, so that northeast slopes appear bright and southwest
slopes appear dark. Color coding is directly related to topographic
height, with green at the lower elevations, rising through yellow and tan,
to white at the highest elevations.
Elevation data used in this image were acquired by the Shuttle Radar
Topography Mission aboard the Space Shuttle Endeavour, launched on Feb.
11, 2000. SRTM used the same radar instrument that comprised the
Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR)
that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed
to collect 3-D measurements of the Earth's surface. To collect the 3-D
data, engineers added a 60-meter (approximately 200-foot) mast, installed
additional C-band and X-band antennas, and improved tracking and
navigation devices. The mission is a cooperative project between NASA,
the National Geospatial-Intelligence Agency (NGA) of the U.S. Department
of Defense and the German and Italian space agencies. It is managed by
NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth
Science Enterprise, Washington, D.C.
Size: 270 kilometers (168 miles) by 145 kilometers (90 miles)
Location: 20.9 degrees South latitude, 134.9 degrees East longitude
Orientation: Northeast toward the top
Image Data: Shaded and colored SRTM elevation model
Date Acquired: February 2000
